/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
* All rights reserved.
*
* The Original Code is: some of this file.
*/
/** \file
* \ingroup bli
*/
#include "MEM_guardedalloc.h"
#include "BLI_math.h"
#include "BLI_math_bits.h"
#include "BLI_utildefines.h"
#include "BLI_strict_flags.h"
/********************************** Polygons *********************************/
void cross_tri_v3(float n[3], const float v1[3], const float v2[3], const float v3[3])
{
float n1[3], n2[3];
n1[0] = v1[0] - v2[0];
n2[0] = v2[0] - v3[0];
n1[1] = v1[1] - v2[1];
n2[1] = v2[1] - v3[1];
n1[2] = v1[2] - v2[2];
n2[2] = v2[2] - v3[2];
n[0] = n1[1] * n2[2] - n1[2] * n2[1];
n[1] = n1[2] * n2[0] - n1[0] * n2[2];
n[2] = n1[0] * n2[1] - n1[1] * n2[0];
}
float normal_tri_v3(float n[3], const float v1[3], const float v2[3], const float v3[3])
{
float n1[3], n2[3];
n1[0] = v1[0] - v2[0];
n2[0] = v2[0] - v3[0];
n1[1] = v1[1] - v2[1];
n2[1] = v2[1] - v3[1];
n1[2] = v1[2] - v2[2];
n2[2] = v2[2] - v3[2];
n[0] = n1[1] * n2[2] - n1[2] * n2[1];
n[1] = n1[2] * n2[0] - n1[0] * n2[2];
n[2] = n1[0] * n2[1] - n1[1] * n2[0];
return normalize_v3(n);
}
float normal_quad_v3(
float n[3], const float v1[3], const float v2[3], const float v3[3], const float v4[3])
{
/* real cross! */
float n1[3], n2[3];
n1[0] = v1[0] - v3[0];
n1[1] = v1[1] - v3[1];
n1[2] = v1[2] - v3[2];
n2[0] = v2[0] - v4[0];
n2[1] = v2[1] - v4[1];
n2[2] = v2[2] - v4[2];
n[0] = n1[1] * n2[2] - n1[2] * n2[1];
n[1] = n1[2] * n2[0] - n1[0] * n2[2];
n[2] = n1[0] * n2[1] - n1[1] * n2[0];
return normalize_v3(n);
}
/**
* Computes the normal of a planar
* polygon See Graphics Gems for
* computing newell normal.
*/
float normal_poly_v3(float n[3], const float verts[][3], unsigned int nr)
{
cross_poly_v3(n, verts, nr);
return normalize_v3(n);
}
float area_quad_v3(const float v1[3], const float v2[3], const float v3[3], const float v4[3])
{
const float verts[4][3] = {{UNPACK3(v1)}, {UNPACK3(v2)}, {UNPACK3(v3)}, {UNPACK3(v4)}};
return area_poly_v3(verts, 4);
}
float area_squared_quad_v3(const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3])
{
const float verts[4][3] = {{UNPACK3(v1)}, {UNPACK3(v2)}, {UNPACK3(v3)}, {UNPACK3(v4)}};
return area_squared_poly_v3(verts, 4);
}
/* Triangles */
float area_tri_v3(const float v1[3], const float v2[3], const float v3[3])
{
float n[3];
cross_tri_v3(n, v1, v2, v3);
return len_v3(n) * 0.5f;
}
float area_squared_tri_v3(const float v1[3], const float v2[3], const float v3[3])
{
float n[3];
cross_tri_v3(n, v1, v2, v3);
mul_v3_fl(n, 0.5f);
return len_squared_v3(n);
}
float area_tri_signed_v3(const float v1[3],
const float v2[3],
const float v3[3],
const float normal[3])
{
float area, n[3];
cross_tri_v3(n, v1, v2, v3);
area = len_v3(n) * 0.5f;
/* negate area for flipped triangles */
if (dot_v3v3(n, normal) < 0.0f) {
area = -area;
}
return area;
}
float area_poly_v3(const float verts[][3], unsigned int nr)
{
float n[3];
cross_poly_v3(n, verts, nr);
return len_v3(n) * 0.5f;
}
float area_squared_poly_v3(const float verts[][3], unsigned int nr)
{
float n[3];
cross_poly_v3(n, verts, nr);
mul_v3_fl(n, 0.5f);
return len_squared_v3(n);
}
/**
* Scalar cross product of a 2d polygon.
*
* - equivalent to ``area * 2``
* - useful for checking polygon winding (a positive value is clockwise).
*/
float cross_poly_v2(const float verts[][2], unsigned int nr)
{
unsigned int a;
float cross;
const float *co_curr, *co_prev;
/* The Trapezium Area Rule */
co_prev = verts[nr - 1];
co_curr = verts[0];
cross = 0.0f;
for (a = 0; a < nr; a++) {
cross += (co_curr[0] - co_prev[0]) * (co_curr[1] + co_prev[1]);
co_prev = co_curr;
co_curr += 2;
}
return cross;
}
void cross_poly_v3(float n[3], const float verts[][3], unsigned int nr)
{
const float *v_prev = verts[nr - 1];
const float *v_curr = verts[0];
unsigned int i;
zero_v3(n);
/* Newell's Method */
for (i = 0; i < nr; v_prev = v_curr, v_curr = verts[++i]) {
add_newell_cross_v3_v3v3(n, v_prev, v_curr);
}
}
float area_poly_v2(const float verts[][2], unsigned int nr)
{
return fabsf(0.5f * cross_poly_v2(verts, nr));
}
float area_poly_signed_v2(const float verts[][2], unsigned int nr)
{
return (0.5f * cross_poly_v2(verts, nr));
}
float area_squared_poly_v2(const float verts[][2], unsigned int nr)
{
float area = area_poly_signed_v2(verts, nr);
return area * area;
}
float cotangent_tri_weight_v3(const float v1[3], const float v2[3], const float v3[3])
{
float a[3], b[3], c[3], c_len;
sub_v3_v3v3(a, v2, v1);
sub_v3_v3v3(b, v3, v1);
cross_v3_v3v3(c, a, b);
c_len = len_v3(c);
if (c_len > FLT_EPSILON) {
return dot_v3v3(a, b) / c_len;
}
return 0.0f;
}
/********************************* Planes **********************************/
/**
* Calculate a plane from a point and a direction,
* \note \a point_no isn't required to be normalized.
*/
void plane_from_point_normal_v3(float r_plane[4], const float plane_co[3], const float plane_no[3])
{
copy_v3_v3(r_plane, plane_no);
r_plane[3] = -dot_v3v3(r_plane, plane_co);
}
/**
* Get a point and a direction from a plane.
*/
void plane_to_point_vector_v3(const float plane[4], float r_plane_co[3], float r_plane_no[3])
{
mul_v3_v3fl(r_plane_co, plane, (-plane[3] / len_squared_v3(plane)));
copy_v3_v3(r_plane_no, plane);
}
/**
* version of #plane_to_point_vector_v3 that gets a unit length vector.
*/
void plane_to_point_vector_v3_normalized(const float plane[4],
float r_plane_co[3],
float r_plane_no[3])
{
const float length = normalize_v3_v3(r_plane_no, plane);
mul_v3_v3fl(r_plane_co, r_plane_no, (-plane[3] / length));
}
/********************************* Volume **********************************/
/**
* The volume from a tetrahedron, points can be in any order
*/
float volume_tetrahedron_v3(const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3])
{
float m[3][3];
sub_v3_v3v3(m[0], v1, v2);
sub_v3_v3v3(m[1], v2, v3);
sub_v3_v3v3(m[2], v3, v4);
return fabsf(determinant_m3_array(m)) / 6.0f;
}
/**
* The volume from a tetrahedron, normal pointing inside gives negative volume
*/
float volume_tetrahedron_signed_v3(const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3])
{
float m[3][3];
sub_v3_v3v3(m[0], v1, v2);
sub_v3_v3v3(m[1], v2, v3);
sub_v3_v3v3(m[2], v3, v4);
return determinant_m3_array(m) / 6.0f;
}
/**
* The volume from a triangle that is made into a tetrahedron.
* This uses a simplified formula where the tip of the tetrahedron is in the world origin.
* Using this method, the total volume of a closed triangle mesh can be calculated.
* Note that you need to divide the result by 6 to get the actual volume.
*/
float volume_tri_tetrahedron_signed_v3_6x(const float v1[3], const float v2[3], const float v3[3])
{
float v_cross[3];
cross_v3_v3v3(v_cross, v1, v2);
float tetra_volume = dot_v3v3(v_cross, v3);
return tetra_volume;
}
float volume_tri_tetrahedron_signed_v3(const float v1[3], const float v2[3], const float v3[3])
{
return volume_tri_tetrahedron_signed_v3_6x(v1, v2, v3) / 6.0f;
}
/********************************* Distance **********************************/
/* distance p to line v1-v2
* using Hesse formula, NO LINE PIECE! */
float dist_squared_to_line_v2(const float p[2], const float l1[2], const float l2[2])
{
float closest[2];
closest_to_line_v2(closest, p, l1, l2);
return len_squared_v2v2(closest, p);
}
float dist_to_line_v2(const float p[2], const float l1[2], const float l2[2])
{
return sqrtf(dist_squared_to_line_v2(p, l1, l2));
}
/* distance p to line-piece v1-v2 */
float dist_squared_to_line_segment_v2(const float p[2], const float l1[2], const float l2[2])
{
float closest[2];
closest_to_line_segment_v2(closest, p, l1, l2);
return len_squared_v2v2(closest, p);
}
float dist_to_line_segment_v2(const float p[2], const float l1[2], const float l2[2])
{
return sqrtf(dist_squared_to_line_segment_v2(p, l1, l2));
}
/* point closest to v1 on line v2-v3 in 2D */
void closest_to_line_segment_v2(float r_close[2],
const float p[2],
const float l1[2],
const float l2[2])
{
float lambda, cp[2];
lambda = closest_to_line_v2(cp, p, l1, l2);
/* flip checks for !finite case (when segment is a point) */
if (!(lambda > 0.0f)) {
copy_v2_v2(r_close, l1);
}
else if (!(lambda < 1.0f)) {
copy_v2_v2(r_close, l2);
}
else {
copy_v2_v2(r_close, cp);
}
}
/* point closest to v1 on line v2-v3 in 3D */
void closest_to_line_segment_v3(float r_close[3],
const float p[3],
const float l1[3],
const float l2[3])
{
float lambda, cp[3];
lambda = closest_to_line_v3(cp, p, l1, l2);
/* flip checks for !finite case (when segment is a point) */
if (!(lambda > 0.0f)) {
copy_v3_v3(r_close, l1);
}
else if (!(lambda < 1.0f)) {
copy_v3_v3(r_close, l2);
}
else {
copy_v3_v3(r_close, cp);
}
}
/**
* Find the closest point on a plane.
*
* \param r_close: Return coordinate
* \param plane: The plane to test against.
* \param pt: The point to find the nearest of
*
* \note non-unit-length planes are supported.
*/
void closest_to_plane_v3(float r_close[3], const float plane[4], const float pt[3])
{
const float len_sq = len_squared_v3(plane);
const float side = plane_point_side_v3(plane, pt);
madd_v3_v3v3fl(r_close, pt, plane, -side / len_sq);
}
void closest_to_plane_normalized_v3(float r_close[3], const float plane[4], const float pt[3])
{
const float side = plane_point_side_v3(plane, pt);
BLI_ASSERT_UNIT_V3(plane);
madd_v3_v3v3fl(r_close, pt, plane, -side);
}
void closest_to_plane3_v3(float r_close[3], const float plane[3], const float pt[3])
{
const float len_sq = len_squared_v3(plane);
const float side = dot_v3v3(plane, pt);
madd_v3_v3v3fl(r_close, pt, plane, -side / len_sq);
}
void closest_to_plane3_normalized_v3(float r_close[3], const float plane[3], const float pt[3])
{
const float side = dot_v3v3(plane, pt);
BLI_ASSERT_UNIT_V3(plane);
madd_v3_v3v3fl(r_close, pt, plane, -side);
}
float dist_signed_squared_to_plane_v3(const float pt[3], const float plane[4])
{
const float len_sq = len_squared_v3(plane);
const float side = plane_point_side_v3(plane, pt);
const float fac = side / len_sq;
return copysignf(len_sq * (fac * fac), side);
}
float dist_squared_to_plane_v3(const float pt[3], const float plane[4])
{
const float len_sq = len_squared_v3(plane);
const float side = plane_point_side_v3(plane, pt);
const float fac = side / len_sq;
/* only difference to code above - no 'copysignf' */
return len_sq * (fac * fac);
}
float dist_signed_squared_to_plane3_v3(const float pt[3], const float plane[3])
{
const float len_sq = len_squared_v3(plane);
const float side = dot_v3v3(plane, pt); /* only difference with 'plane[4]' version */
const float fac = side / len_sq;
return copysignf(len_sq * (fac * fac), side);
}
float dist_squared_to_plane3_v3(const float pt[3], const float plane[3])
{
const float len_sq = len_squared_v3(plane);
const float side = dot_v3v3(plane, pt); /* only difference with 'plane[4]' version */
const float fac = side / len_sq;
/* only difference to code above - no 'copysignf' */
return len_sq * (fac * fac);
}
/**
* Return the signed distance from the point to the plane.
*/
float dist_signed_to_plane_v3(const float pt[3], const float plane[4])
{
const float len_sq = len_squared_v3(plane);
const float side = plane_point_side_v3(plane, pt);
const float fac = side / len_sq;
return sqrtf(len_sq) * fac;
}
float dist_to_plane_v3(const float pt[3], const float plane[4])
{
return fabsf(dist_signed_to_plane_v3(pt, plane));
}
float dist_signed_to_plane3_v3(const float pt[3], const float plane[3])
{
const float len_sq = len_squared_v3(plane);
const float side = dot_v3v3(plane, pt); /* only difference with 'plane[4]' version */
const float fac = side / len_sq;
return sqrtf(len_sq) * fac;
}
float dist_to_plane3_v3(const float pt[3], const float plane[3])
{
return fabsf(dist_signed_to_plane3_v3(pt, plane));
}
/* distance v1 to line-piece l1-l2 in 3D */
float dist_squared_to_line_segment_v3(const float p[3], const float l1[3], const float l2[3])
{
float closest[3];
closest_to_line_segment_v3(closest, p, l1, l2);
return len_squared_v3v3(closest, p);
}
float dist_to_line_segment_v3(const float p[3], const float l1[3], const float l2[3])
{
return sqrtf(dist_squared_to_line_segment_v3(p, l1, l2));
}
float dist_squared_to_line_v3(const float p[3], const float l1[3], const float l2[3])
{
float closest[3];
closest_to_line_v3(closest, p, l1, l2);
return len_squared_v3v3(closest, p);
}
float dist_to_line_v3(const float p[3], const float l1[3], const float l2[3])
{
return sqrtf(dist_squared_to_line_v3(p, l1, l2));
}
/**
* Check if \a p is inside the 2x planes defined by ``(v1, v2, v3)``
* where the 3x points define 2x planes.
*
* \param axis_ref: used when v1,v2,v3 form a line and to check if the corner is concave/convex.
*
* \note the distance from \a v1 & \a v3 to \a v2 doesn't matter
* (it just defines the planes).
*
* \return the lowest squared distance to either of the planes.
* where ``(return < 0.0)`` is outside.
*
*
* v1
* +
* /
* x - out / x - inside
* /
* +----+
* v2 v3
* x - also outside
*
*/
float dist_signed_squared_to_corner_v3v3v3(const float p[3],
const float v1[3],
const float v2[3],
const float v3[3],
const float axis_ref[3])
{
float dir_a[3], dir_b[3];
float plane_a[3], plane_b[3];
float dist_a, dist_b;
float axis[3];
float s_p_v2[3];
bool flip = false;
sub_v3_v3v3(dir_a, v1, v2);
sub_v3_v3v3(dir_b, v3, v2);
cross_v3_v3v3(axis, dir_a, dir_b);
if ((len_squared_v3(axis) < FLT_EPSILON)) {
copy_v3_v3(axis, axis_ref);
}
else if (dot_v3v3(axis, axis_ref) < 0.0f) {
/* concave */
flip = true;
negate_v3(axis);
}
cross_v3_v3v3(plane_a, dir_a, axis);
cross_v3_v3v3(plane_b, axis, dir_b);
#if 0
plane_from_point_normal_v3(plane_a, v2, plane_a);
plane_from_point_normal_v3(plane_b, v2, plane_b);
dist_a = dist_signed_squared_to_plane_v3(p, plane_a);
dist_b = dist_signed_squared_to_plane_v3(p, plane_b);
#else
/* calculate without the planes 4th component to avoid float precision issues */
sub_v3_v3v3(s_p_v2, p, v2);
dist_a = dist_signed_squared_to_plane3_v3(s_p_v2, plane_a);
dist_b = dist_signed_squared_to_plane3_v3(s_p_v2, plane_b);
#endif
if (flip) {
return min_ff(dist_a, dist_b);
}
return max_ff(dist_a, dist_b);
}
/**
* Compute the squared distance of a point to a line (defined as ray).
* \param ray_origin: A point on the line.
* \param ray_direction: Normalized direction of the line.
* \param co: Point to which the distance is to be calculated.
*/
float dist_squared_to_ray_v3_normalized(const float ray_origin[3],
const float ray_direction[3],
const float co[3])
{
float origin_to_co[3];
sub_v3_v3v3(origin_to_co, co, ray_origin);
float origin_to_proj[3];
project_v3_v3v3_normalized(origin_to_proj, origin_to_co, ray_direction);
float co_projected_on_ray[3];
add_v3_v3v3(co_projected_on_ray, ray_origin, origin_to_proj);
return len_squared_v3v3(co, co_projected_on_ray);
}
/**
* Find the closest point in a seg to a ray and return the distance squared.
* \param r_point: Is the point on segment closest to ray
* (or to ray_origin if the ray and the segment are parallel).
* \param r_depth: the distance of r_point projection on ray to the ray_origin.
*/
float dist_squared_ray_to_seg_v3(const float ray_origin[3],
const float ray_direction[3],
const float v0[3],
const float v1[3],
float r_point[3],
float *r_depth)
{
float lambda, depth;
if (isect_ray_line_v3(ray_origin, ray_direction, v0, v1, &lambda)) {
if (lambda <= 0.0f) {
copy_v3_v3(r_point, v0);
}
else if (lambda >= 1.0f) {
copy_v3_v3(r_point, v1);
}
else {
interp_v3_v3v3(r_point, v0, v1, lambda);
}
}
else {
/* has no nearest point, only distance squared. */
/* Calculate the distance to the point v0 then */
copy_v3_v3(r_point, v0);
}
float dvec[3];
sub_v3_v3v3(dvec, r_point, ray_origin);
depth = dot_v3v3(dvec, ray_direction);
if (r_depth) {
*r_depth = depth;
}
return len_squared_v3(dvec) - square_f(depth);
}
/* Returns the coordinates of the nearest vertex and
* the farthest vertex from a plane (or normal). */
void aabb_get_near_far_from_plane(const float plane_no[3],
const float bbmin[3],
const float bbmax[3],
float bb_near[3],
float bb_afar[3])
{
if (plane_no[0] < 0.0f) {
bb_near[0] = bbmax[0];
bb_afar[0] = bbmin[0];
}
else {
bb_near[0] = bbmin[0];
bb_afar[0] = bbmax[0];
}
if (plane_no[1] < 0.0f) {
bb_near[1] = bbmax[1];
bb_afar[1] = bbmin[1];
}
else {
bb_near[1] = bbmin[1];
bb_afar[1] = bbmax[1];
}
if (plane_no[2] < 0.0f) {
bb_near[2] = bbmax[2];
bb_afar[2] = bbmin[2];
}
else {
bb_near[2] = bbmin[2];
bb_afar[2] = bbmax[2];
}
}
/* -------------------------------------------------------------------- */
/** \name dist_squared_to_ray_to_aabb and helpers
* \{ */
void dist_squared_ray_to_aabb_v3_precalc(struct DistRayAABB_Precalc *neasrest_precalc,
const float ray_origin[3],
const float ray_direction[3])
{
copy_v3_v3(neasrest_precalc->ray_origin, ray_origin);
copy_v3_v3(neasrest_precalc->ray_direction, ray_direction);
for (int i = 0; i < 3; i++) {
neasrest_precalc->ray_inv_dir[i] = (neasrest_precalc->ray_direction[i] != 0.0f) ?
(1.0f / neasrest_precalc->ray_direction[i]) :
FLT_MAX;
}
}
/**
* Returns the distance from a ray to a bound-box (projected on ray)
*/
float dist_squared_ray_to_aabb_v3(const struct DistRayAABB_Precalc *data,
const float bb_min[3],
const float bb_max[3],
float r_point[3],
float *r_depth)
{
// bool r_axis_closest[3];
float local_bvmin[3], local_bvmax[3];
aabb_get_near_far_from_plane(data->ray_direction, bb_min, bb_max, local_bvmin, local_bvmax);
const float tmin[3] = {
(local_bvmin[0] - data->ray_origin[0]) * data->ray_inv_dir[0],
(local_bvmin[1] - data->ray_origin[1]) * data->ray_inv_dir[1],
(local_bvmin[2] - data->ray_origin[2]) * data->ray_inv_dir[2],
};
const float tmax[3] = {
(local_bvmax[0] - data->ray_origin[0]) * data->ray_inv_dir[0],
(local_bvmax[1] - data->ray_origin[1]) * data->ray_inv_dir[1],
(local_bvmax[2] - data->ray_origin[2]) * data->ray_inv_dir[2],
};
/* `va` and `vb` are the coordinates of the AABB edge closest to the ray */
float va[3], vb[3];
/* `rtmin` and `rtmax` are the minimum and maximum distances of the ray hits on the AABB */
float rtmin, rtmax;
int main_axis;
if ((tmax[0] <= tmax[1]) && (tmax[0] <= tmax[2])) {
rtmax = tmax[0];
va[0] = vb[0] = local_bvmax[0];
main_axis = 3;
// r_axis_closest[0] = neasrest_precalc->ray_direction[0] < 0.0f;
}
else if ((tmax[1] <= tmax[0]) && (tmax[1] <= tmax[2])) {
rtmax = tmax[1];
va[1] = vb[1] = local_bvmax[1];
main_axis = 2;
// r_axis_closest[1] = neasrest_precalc->ray_direction[1] < 0.0f;
}
else {
rtmax = tmax[2];
va[2] = vb[2] = local_bvmax[2];
main_axis = 1;
// r_axis_closest[2] = neasrest_precalc->ray_direction[2] < 0.0f;
}
if ((tmin[0] >= tmin[1]) && (tmin[0] >= tmin[2])) {
rtmin = tmin[0];
va[0] = vb[0] = local_bvmin[0];
main_axis -= 3;
// r_axis_closest[0] = neasrest_precalc->ray_direction[0] >= 0.0f;
}
else if ((tmin[1] >= tmin[0]) && (tmin[1] >= tmin[2])) {
rtmin = tmin[1];
va[1] = vb[1] = local_bvmin[1];
main_axis -= 1;
// r_axis_closest[1] = neasrest_precalc->ray_direction[1] >= 0.0f;
}
else {
rtmin = tmin[2];
va[2] = vb[2] = local_bvmin[2];
main_axis -= 2;
// r_axis_closest[2] = neasrest_precalc->ray_direction[2] >= 0.0f;
}
if (main_axis < 0) {
main_axis += 3;
}
/* if rtmin <= rtmax, ray intersect `AABB` */
if (rtmin <= rtmax) {
float dvec[3];
copy_v3_v3(r_point, local_bvmax);
sub_v3_v3v3(dvec, local_bvmax, data->ray_origin);
*r_depth = dot_v3v3(dvec, data->ray_direction);
return 0.0f;
}
if (data->ray_direction[main_axis] >= 0.0f) {
va[main_axis] = local_bvmin[main_axis];
vb[main_axis] = local_bvmax[main_axis];
}
else {
va[main_axis] = local_bvmax[main_axis];
vb[main_axis] = local_bvmin[main_axis];
}
return dist_squared_ray_to_seg_v3(
data->ray_origin, data->ray_direction, va, vb, r_point, r_depth);
}
float dist_squared_ray_to_aabb_v3_simple(const float ray_origin[3],
const float ray_direction[3],
const float bb_min[3],
const float bb_max[3],
float r_point[3],
float *r_depth)
{
struct DistRayAABB_Precalc data;
dist_squared_ray_to_aabb_v3_precalc(&data, ray_origin, ray_direction);
return dist_squared_ray_to_aabb_v3(&data, bb_min, bb_max, r_point, r_depth);
}
/** \} */
/* -------------------------------------------------------------------- */
/** \name dist_squared_to_projected_aabb and helpers
* \{ */
/**
* \param projmat: Projection Matrix (usually perspective
* matrix multiplied by object matrix).
*/
void dist_squared_to_projected_aabb_precalc(struct DistProjectedAABBPrecalc *precalc,
const float projmat[4][4],
const float winsize[2],
const float mval[2])
{
float win_half[2], relative_mval[2], px[4], py[4];
mul_v2_v2fl(win_half, winsize, 0.5f);
sub_v2_v2v2(precalc->mval, mval, win_half);
relative_mval[0] = precalc->mval[0] / win_half[0];
relative_mval[1] = precalc->mval[1] / win_half[1];
copy_m4_m4(precalc->pmat, projmat);
for (int i = 0; i < 4; i++) {
px[i] = precalc->pmat[i][0] - precalc->pmat[i][3] * relative_mval[0];
py[i] = precalc->pmat[i][1] - precalc->pmat[i][3] * relative_mval[1];
precalc->pmat[i][0] *= win_half[0];
precalc->pmat[i][1] *= win_half[1];
}
#if 0
float projmat_trans[4][4];
transpose_m4_m4(projmat_trans, projmat);
if (!isect_plane_plane_plane_v3(
projmat_trans[0], projmat_trans[1], projmat_trans[3], precalc->ray_origin)) {
/* Orthographic projection. */
isect_plane_plane_v3(px, py, precalc->ray_origin, precalc->ray_direction);
}
else {
/* Perspective projection. */
cross_v3_v3v3(precalc->ray_direction, py, px);
//normalize_v3(precalc->ray_direction);
}
#else
if (!isect_plane_plane_v3(px, py, precalc->ray_origin, precalc->ray_direction)) {
/* Matrix with weird coplanar planes. Undetermined origin.*/
zero_v3(precalc->ray_origin);
precalc->ray_direction[0] = precalc->pmat[0][3];
precalc->ray_direction[1] = precalc->pmat[1][3];
precalc->ray_direction[2] = precalc->pmat[2][3];
}
#endif
for (int i = 0; i < 3; i++) {
precalc->ray_inv_dir[i] = (precalc->ray_direction[i] != 0.0f) ?
(1.0f / precalc->ray_direction[i]) :
FLT_MAX;
}
}
/* Returns the distance from a 2d coordinate to a BoundBox (Projected) */
float dist_squared_to_projected_aabb(struct DistProjectedAABBPrecalc *data,
const float bbmin[3],
const float bbmax[3],
bool r_axis_closest[3])
{
float local_bvmin[3], local_bvmax[3];
aabb_get_near_far_from_plane(data->ray_direction, bbmin, bbmax, local_bvmin, local_bvmax);
const float tmin[3] = {
(local_bvmin[0] - data->ray_origin[0]) * data->ray_inv_dir[0],
(local_bvmin[1] - data->ray_origin[1]) * data->ray_inv_dir[1],
(local_bvmin[2] - data->ray_origin[2]) * data->ray_inv_dir[2],
};
const float tmax[3] = {
(local_bvmax[0] - data->ray_origin[0]) * data->ray_inv_dir[0],
(local_bvmax[1] - data->ray_origin[1]) * data->ray_inv_dir[1],
(local_bvmax[2] - data->ray_origin[2]) * data->ray_inv_dir[2],
};
/* `va` and `vb` are the coordinates of the AABB edge closest to the ray */
float va[3], vb[3];
/* `rtmin` and `rtmax` are the minimum and maximum distances of the ray hits on the AABB */
float rtmin, rtmax;
int main_axis;
r_axis_closest[0] = false;
r_axis_closest[1] = false;
r_axis_closest[2] = false;
if ((tmax[0] <= tmax[1]) && (tmax[0] <= tmax[2])) {
rtmax = tmax[0];
va[0] = vb[0] = local_bvmax[0];
main_axis = 3;
r_axis_closest[0] = data->ray_direction[0] < 0.0f;
}
else if ((tmax[1] <= tmax[0]) && (tmax[1] <= tmax[2])) {
rtmax = tmax[1];
va[1] = vb[1] = local_bvmax[1];
main_axis = 2;
r_axis_closest[1] = data->ray_direction[1] < 0.0f;
}
else {
rtmax = tmax[2];
va[2] = vb[2] = local_bvmax[2];
main_axis = 1;
r_axis_closest[2] = data->ray_direction[2] < 0.0f;
}
if ((tmin[0] >= tmin[1]) && (tmin[0] >= tmin[2])) {
rtmin = tmin[0];
va[0] = vb[0] = local_bvmin[0];
main_axis -= 3;
r_axis_closest[0] = data->ray_direction[0] >= 0.0f;
}
else if ((tmin[1] >= tmin[0]) && (tmin[1] >= tmin[2])) {
rtmin = tmin[1];
va[1] = vb[1] = local_bvmin[1];
main_axis -= 1;
r_axis_closest[1] = data->ray_direction[1] >= 0.0f;
}
else {
rtmin = tmin[2];
va[2] = vb[2] = local_bvmin[2];
main_axis -= 2;
r_axis_closest[2] = data->ray_direction[2] >= 0.0f;
}
if (main_axis < 0) {
main_axis += 3;
}
/* if rtmin <= rtmax, ray intersect `AABB` */
if (rtmin <= rtmax) {
return 0;
}
if (data->ray_direction[main_axis] >= 0.0f) {
va[main_axis] = local_bvmin[main_axis];
vb[main_axis] = local_bvmax[main_axis];
}
else {
va[main_axis] = local_bvmax[main_axis];
vb[main_axis] = local_bvmin[main_axis];
}
float scale = fabsf(local_bvmax[main_axis] - local_bvmin[main_axis]);
float va2d[2] = {
(dot_m4_v3_row_x(data->pmat, va) + data->pmat[3][0]),
(dot_m4_v3_row_y(data->pmat, va) + data->pmat[3][1]),
};
float vb2d[2] = {
(va2d[0] + data->pmat[main_axis][0] * scale),
(va2d[1] + data->pmat[main_axis][1] * scale),
};
float w_a = mul_project_m4_v3_zfac(data->pmat, va);
if (w_a != 1.0f) {
/* Perspective Projection. */
float w_b = w_a + data->pmat[main_axis][3] * scale;
va2d[0] /= w_a;
va2d[1] /= w_a;
vb2d[0] /= w_b;
vb2d[1] /= w_b;
}
float dvec[2], edge[2], lambda, rdist_sq;
sub_v2_v2v2(dvec, data->mval, va2d);
sub_v2_v2v2(edge, vb2d, va2d);
lambda = dot_v2v2(dvec, edge);
if (lambda != 0.0f) {
lambda /= len_squared_v2(edge);
if (lambda <= 0.0f) {
rdist_sq = len_squared_v2v2(data->mval, va2d);
r_axis_closest[main_axis] = true;
}
else if (lambda >= 1.0f) {
rdist_sq = len_squared_v2v2(data->mval, vb2d);
r_axis_closest[main_axis] = false;
}
else {
madd_v2_v2fl(va2d, edge, lambda);
rdist_sq = len_squared_v2v2(data->mval, va2d);
r_axis_closest[main_axis] = lambda < 0.5f;
}
}
else {
rdist_sq = len_squared_v2v2(data->mval, va2d);
}
return rdist_sq;
}
float dist_squared_to_projected_aabb_simple(const float projmat[4][4],
const float winsize[2],
const float mval[2],
const float bbmin[3],
const float bbmax[3])
{
struct DistProjectedAABBPrecalc data;
dist_squared_to_projected_aabb_precalc(&data, projmat, winsize, mval);
bool dummy[3] = {true, true, true};
return dist_squared_to_projected_aabb(&data, bbmin, bbmax, dummy);
}
/** \} */
/* Adapted from "Real-Time Collision Detection" by Christer Ericson,
* published by Morgan Kaufmann Publishers, copyright 2005 Elsevier Inc.
*
* Set 'r' to the point in triangle (a, b, c) closest to point 'p' */
void closest_on_tri_to_point_v3(
float r[3], const float p[3], const float v1[3], const float v2[3], const float v3[3])
{
float ab[3], ac[3], ap[3], d1, d2;
float bp[3], d3, d4, vc, cp[3], d5, d6, vb, va;
float denom, v, w;
/* Check if P in vertex region outside A */
sub_v3_v3v3(ab, v2, v1);
sub_v3_v3v3(ac, v3, v1);
sub_v3_v3v3(ap, p, v1);
d1 = dot_v3v3(ab, ap);
d2 = dot_v3v3(ac, ap);
if (d1 <= 0.0f && d2 <= 0.0f) {
/* barycentric coordinates (1,0,0) */
copy_v3_v3(r, v1);
return;
}
/* Check if P in vertex region outside B */
sub_v3_v3v3(bp, p, v2);
d3 = dot_v3v3(ab, bp);
d4 = dot_v3v3(ac, bp);
if (d3 >= 0.0f && d4 <= d3) {
/* barycentric coordinates (0,1,0) */
copy_v3_v3(r, v2);
return;
}
/* Check if P in edge region of AB, if so return projection of P onto AB */
vc = d1 * d4 - d3 * d2;
if (vc <= 0.0f && d1 >= 0.0f && d3 <= 0.0f) {
v = d1 / (d1 - d3);
/* barycentric coordinates (1-v,v,0) */
madd_v3_v3v3fl(r, v1, ab, v);
return;
}
/* Check if P in vertex region outside C */
sub_v3_v3v3(cp, p, v3);
d5 = dot_v3v3(ab, cp);
d6 = dot_v3v3(ac, cp);
if (d6 >= 0.0f && d5 <= d6) {
/* barycentric coordinates (0,0,1) */
copy_v3_v3(r, v3);
return;
}
/* Check if P in edge region of AC, if so return projection of P onto AC */
vb = d5 * d2 - d1 * d6;
if (vb <= 0.0f && d2 >= 0.0f && d6 <= 0.0f) {
w = d2 / (d2 - d6);
/* barycentric coordinates (1-w,0,w) */
madd_v3_v3v3fl(r, v1, ac, w);
return;
}
/* Check if P in edge region of BC, if so return projection of P onto BC */
va = d3 * d6 - d5 * d4;
if (va <= 0.0f && (d4 - d3) >= 0.0f && (d5 - d6) >= 0.0f) {
w = (d4 - d3) / ((d4 - d3) + (d5 - d6));
/* barycentric coordinates (0,1-w,w) */
sub_v3_v3v3(r, v3, v2);
mul_v3_fl(r, w);
add_v3_v3(r, v2);
return;
}
/* P inside face region. Compute Q through its barycentric coordinates (u,v,w) */
denom = 1.0f / (va + vb + vc);
v = vb * denom;
w = vc * denom;
/* = u*a + v*b + w*c, u = va * denom = 1.0f - v - w */
/* ac * w */
mul_v3_fl(ac, w);
/* a + ab * v */
madd_v3_v3v3fl(r, v1, ab, v);
/* a + ab * v + ac * w */
add_v3_v3(r, ac);
}
/******************************* Intersection ********************************/
/* intersect Line-Line, shorts */
int isect_seg_seg_v2_int(const int v1[2], const int v2[2], const int v3[2], const int v4[2])
{
float div, lambda, mu;
div = (float)((v2[0] - v1[0]) * (v4[1] - v3[1]) - (v2[1] - v1[1]) * (v4[0] - v3[0]));
if (div == 0.0f) {
return ISECT_LINE_LINE_COLINEAR;
}
lambda = (float)((v1[1] - v3[1]) * (v4[0] - v3[0]) - (v1[0] - v3[0]) * (v4[1] - v3[1])) / div;
mu = (float)((v1[1] - v3[1]) * (v2[0] - v1[0]) - (v1[0] - v3[0]) * (v2[1] - v1[1])) / div;
if (lambda >= 0.0f && lambda <= 1.0f && mu >= 0.0f && mu <= 1.0f) {
if (lambda == 0.0f || lambda == 1.0f || mu == 0.0f || mu == 1.0f) {
return ISECT_LINE_LINE_EXACT;
}
return ISECT_LINE_LINE_CROSS;
}
return ISECT_LINE_LINE_NONE;
}
/* intersect Line-Line, floats - gives intersection point */
int isect_line_line_v2_point(
const float v0[2], const float v1[2], const float v2[2], const float v3[2], float r_vi[2])
{
float s10[2], s32[2];
float div;
sub_v2_v2v2(s10, v1, v0);
sub_v2_v2v2(s32, v3, v2);
div = cross_v2v2(s10, s32);
if (div != 0.0f) {
const float u = cross_v2v2(v1, v0);
const float v = cross_v2v2(v3, v2);
r_vi[0] = ((s32[0] * u) - (s10[0] * v)) / div;
r_vi[1] = ((s32[1] * u) - (s10[1] * v)) / div;
return ISECT_LINE_LINE_CROSS;
}
return ISECT_LINE_LINE_COLINEAR;
}
/* intersect Line-Line, floats */
int isect_seg_seg_v2(const float v1[2], const float v2[2], const float v3[2], const float v4[2])
{
float div, lambda, mu;
div = (v2[0] - v1[0]) * (v4[1] - v3[1]) - (v2[1] - v1[1]) * (v4[0] - v3[0]);
if (div == 0.0f) {
return ISECT_LINE_LINE_COLINEAR;
}
lambda = ((float)(v1[1] - v3[1]) * (v4[0] - v3[0]) - (v1[0] - v3[0]) * (v4[1] - v3[1])) / div;
mu = ((float)(v1[1] - v3[1]) * (v2[0] - v1[0]) - (v1[0] - v3[0]) * (v2[1] - v1[1])) / div;
if (lambda >= 0.0f && lambda <= 1.0f && mu >= 0.0f && mu <= 1.0f) {
if (lambda == 0.0f || lambda == 1.0f || mu == 0.0f || mu == 1.0f) {
return ISECT_LINE_LINE_EXACT;
}
return ISECT_LINE_LINE_CROSS;
}
return ISECT_LINE_LINE_NONE;
}
/* Returns a point on each segment that is closest to the other. */
void isect_seg_seg_v3(const float a0[3],
const float a1[3],
const float b0[3],
const float b1[3],
float r_a[3],
float r_b[3])
{
float fac_a, fac_b;
float a_dir[3], b_dir[3], a0b0[3], crs_ab[3];
sub_v3_v3v3(a_dir, a1, a0);
sub_v3_v3v3(b_dir, b1, b0);
sub_v3_v3v3(a0b0, b0, a0);
cross_v3_v3v3(crs_ab, b_dir, a_dir);
const float nlen = len_squared_v3(crs_ab);
if (nlen == 0.0f) {
/* Parallel Lines */
/* In this case return any point that
* is between the closest segments. */
float a0b1[3], a1b0[3], len_a, len_b, fac1, fac2;
sub_v3_v3v3(a0b1, b1, a0);
sub_v3_v3v3(a1b0, b0, a1);
len_a = len_squared_v3(a_dir);
len_b = len_squared_v3(b_dir);
if (len_a) {
fac1 = dot_v3v3(a0b0, a_dir);
fac2 = dot_v3v3(a0b1, a_dir);
CLAMP(fac1, 0.0f, len_a);
CLAMP(fac2, 0.0f, len_a);
fac_a = (fac1 + fac2) / (2 * len_a);
}
else {
fac_a = 0.0f;
}
if (len_b) {
fac1 = -dot_v3v3(a0b0, b_dir);
fac2 = -dot_v3v3(a1b0, b_dir);
CLAMP(fac1, 0.0f, len_b);
CLAMP(fac2, 0.0f, len_b);
fac_b = (fac1 + fac2) / (2 * len_b);
}
else {
fac_b = 0.0f;
}
}
else {
float c[3], cray[3];
sub_v3_v3v3(c, crs_ab, a0b0);
cross_v3_v3v3(cray, c, b_dir);
fac_a = dot_v3v3(cray, crs_ab) / nlen;
cross_v3_v3v3(cray, c, a_dir);
fac_b = dot_v3v3(cray, crs_ab) / nlen;
CLAMP(fac_a, 0.0f, 1.0f);
CLAMP(fac_b, 0.0f, 1.0f);
}
madd_v3_v3v3fl(r_a, a0, a_dir, fac_a);
madd_v3_v3v3fl(r_b, b0, b_dir, fac_b);
}
/**
* Get intersection point of two 2D segments.
*
* \param endpoint_bias: Bias to use when testing for end-point overlap.
* A positive value considers intersections that extend past the endpoints,
* negative values contract the endpoints.
* Note the bias is applied to a 0-1 factor, not scaled to the length of segments.
*
* \returns intersection type:
* - -1: collinear.
* - 1: intersection.
* - 0: no intersection.
*/
int isect_seg_seg_v2_point_ex(const float v0[2],
const float v1[2],
const float v2[2],
const float v3[2],
const float endpoint_bias,
float r_vi[2])
{
float s10[2], s32[2], s30[2], d;
const float eps = 1e-6f;
const float endpoint_min = -endpoint_bias;
const float endpoint_max = endpoint_bias + 1.0f;
sub_v2_v2v2(s10, v1, v0);
sub_v2_v2v2(s32, v3, v2);
sub_v2_v2v2(s30, v3, v0);
d = cross_v2v2(s10, s32);
if (d != 0) {
float u, v;
u = cross_v2v2(s30, s32) / d;
v = cross_v2v2(s10, s30) / d;
if ((u >= endpoint_min && u <= endpoint_max) && (v >= endpoint_min && v <= endpoint_max)) {
/* intersection */
float vi_test[2];
float s_vi_v2[2];
madd_v2_v2v2fl(vi_test, v0, s10, u);
/* When 'd' approaches zero, float precision lets non-overlapping co-linear segments
* detect as an intersection. So re-calculate 'v' to ensure the point overlaps both.
* see T45123 */
/* inline since we have most vars already */
#if 0
v = line_point_factor_v2(ix_test, v2, v3);
#else
sub_v2_v2v2(s_vi_v2, vi_test, v2);
v = (dot_v2v2(s32, s_vi_v2) / dot_v2v2(s32, s32));
#endif
if (v >= endpoint_min && v <= endpoint_max) {
copy_v2_v2(r_vi, vi_test);
return 1;
}
}
/* out of segment intersection */
return -1;
}
if ((cross_v2v2(s10, s30) == 0.0f) && (cross_v2v2(s32, s30) == 0.0f)) {
/* equal lines */
float s20[2];
float u_a, u_b;
if (equals_v2v2(v0, v1)) {
if (len_squared_v2v2(v2, v3) > square_f(eps)) {
/* use non-point segment as basis */
SWAP(const float *, v0, v2);
SWAP(const float *, v1, v3);
sub_v2_v2v2(s10, v1, v0);
sub_v2_v2v2(s30, v3, v0);
}
else { /* both of segments are points */
if (equals_v2v2(v0, v2)) { /* points are equal */
copy_v2_v2(r_vi, v0);
return 1;
}
/* two different points */
return -1;
}
}
sub_v2_v2v2(s20, v2, v0);
u_a = dot_v2v2(s20, s10) / dot_v2v2(s10, s10);
u_b = dot_v2v2(s30, s10) / dot_v2v2(s10, s10);
if (u_a > u_b) {
SWAP(float, u_a, u_b);
}
if (u_a > endpoint_max || u_b < endpoint_min) {
/* non-overlapping segments */
return -1;
}
if (max_ff(0.0f, u_a) == min_ff(1.0f, u_b)) {
/* one common point: can return result */
madd_v2_v2v2fl(r_vi, v0, s10, max_ff(0, u_a));
return 1;
}
}
/* lines are collinear */
return -1;
}
int isect_seg_seg_v2_point(
const float v0[2], const float v1[2], const float v2[2], const float v3[2], float r_vi[2])
{
const float endpoint_bias = 1e-6f;
return isect_seg_seg_v2_point_ex(v0, v1, v2, v3, endpoint_bias, r_vi);
}
bool isect_seg_seg_v2_simple(const float v1[2],
const float v2[2],
const float v3[2],
const float v4[2])
{
#define CCW(A, B, C) ((C[1] - A[1]) * (B[0] - A[0]) > (B[1] - A[1]) * (C[0] - A[0]))
return CCW(v1, v3, v4) != CCW(v2, v3, v4) && CCW(v1, v2, v3) != CCW(v1, v2, v4);
#undef CCW
}
/**
* If intersection == ISECT_LINE_LINE_CROSS or ISECT_LINE_LINE_NONE:
*
* pt = v1 + lambda * (v2 - v1) = v3 + mu * (v4 - v3)
*
* \returns intersection type:
* - ISECT_LINE_LINE_COLINEAR: collinear.
* - ISECT_LINE_LINE_EXACT: intersection at an endpoint of either.
* - ISECT_LINE_LINE_CROSS: interaction, not at an endpoint.
* - ISECT_LINE_LINE_NONE: no intersection.
* Also returns lambda and mu in r_lambda and r_mu.
*/
int isect_seg_seg_v2_lambda_mu_db(const double v1[2],
const double v2[2],
const double v3[2],
const double v4[2],
double *r_lambda,
double *r_mu)
{
double div, lambda, mu;
div = (v2[0] - v1[0]) * (v4[1] - v3[1]) - (v2[1] - v1[1]) * (v4[0] - v3[0]);
if (fabs(div) < DBL_EPSILON) {
return ISECT_LINE_LINE_COLINEAR;
}
lambda = ((v1[1] - v3[1]) * (v4[0] - v3[0]) - (v1[0] - v3[0]) * (v4[1] - v3[1])) / div;
mu = ((v1[1] - v3[1]) * (v2[0] - v1[0]) - (v1[0] - v3[0]) * (v2[1] - v1[1])) / div;
if (r_lambda) {
*r_lambda = lambda;
}
if (r_mu) {
*r_mu = mu;
}
if (lambda >= 0.0 && lambda <= 1.0 && mu >= 0.0 && mu <= 1.0) {
if (lambda == 0.0 || lambda == 1.0 || mu == 0.0 || mu == 1.0) {
return ISECT_LINE_LINE_EXACT;
}
return ISECT_LINE_LINE_CROSS;
}
return ISECT_LINE_LINE_NONE;
}
/**
* \param l1, l2: Coordinates (point of line).
* \param sp, r: Coordinate and radius (sphere).
* \return r_p1, r_p2: Intersection coordinates.
*
* \note The order of assignment for intersection points (\a r_p1, \a r_p2) is predictable,
* based on the direction defined by ``l2 - l1``,
* this direction compared with the normal of each point on the sphere:
* \a r_p1 always has a >= 0.0 dot product.
* \a r_p2 always has a <= 0.0 dot product.
* For example, when \a l1 is inside the sphere and \a l2 is outside,
* \a r_p1 will always be between \a l1 and \a l2.
*/
int isect_line_sphere_v3(const float l1[3],
const float l2[3],
const float sp[3],
const float r,
float r_p1[3],
float r_p2[3])
{
/* adapted for use in blender by Campbell Barton - 2011
*
* atelier iebele abel - 2001
*
* http://www.iebele.nl
*
* sphere_line_intersection function adapted from:
* http://astronomy.swin.edu.au/pbourke/geometry/sphereline
* Paul Bourke
*/
const float ldir[3] = {
l2[0] - l1[0],
l2[1] - l1[1],
l2[2] - l1[2],
};
const float a = len_squared_v3(ldir);
const float b = 2.0f * (ldir[0] * (l1[0] - sp[0]) + ldir[1] * (l1[1] - sp[1]) +
ldir[2] * (l1[2] - sp[2]));
const float c = len_squared_v3(sp) + len_squared_v3(l1) - (2.0f * dot_v3v3(sp, l1)) - (r * r);
const float i = b * b - 4.0f * a * c;
float mu;
if (i < 0.0f) {
/* no intersections */
return 0;
}
if (i == 0.0f) {
/* one intersection */
mu = -b / (2.0f * a);
madd_v3_v3v3fl(r_p1, l1, ldir, mu);
return 1;
}
if (i > 0.0f) {
const float i_sqrt = sqrtf(i); /* avoid calc twice */
/* first intersection */
mu = (-b + i_sqrt) / (2.0f * a);
madd_v3_v3v3fl(r_p1, l1, ldir, mu);
/* second intersection */
mu = (-b - i_sqrt) / (2.0f * a);
madd_v3_v3v3fl(r_p2, l1, ldir, mu);
return 2;
}
/* math domain error - nan */
return -1;
}
/* keep in sync with isect_line_sphere_v3 */
int isect_line_sphere_v2(const float l1[2],
const float l2[2],
const float sp[2],
const float r,
float r_p1[2],
float r_p2[2])
{
const float ldir[2] = {l2[0] - l1[0], l2[1] - l1[1]};
const float a = dot_v2v2(ldir, ldir);
const float b = 2.0f * (ldir[0] * (l1[0] - sp[0]) + ldir[1] * (l1[1] - sp[1]));
const float c = dot_v2v2(sp, sp) + dot_v2v2(l1, l1) - (2.0f * dot_v2v2(sp, l1)) - (r * r);
const float i = b * b - 4.0f * a * c;
float mu;
if (i < 0.0f) {
/* no intersections */
return 0;
}
if (i == 0.0f) {
/* one intersection */
mu = -b / (2.0f * a);
madd_v2_v2v2fl(r_p1, l1, ldir, mu);
return 1;
}
if (i > 0.0f) {
const float i_sqrt = sqrtf(i); /* avoid calc twice */
/* first intersection */
mu = (-b + i_sqrt) / (2.0f * a);
madd_v2_v2v2fl(r_p1, l1, ldir, mu);
/* second intersection */
mu = (-b - i_sqrt) / (2.0f * a);
madd_v2_v2v2fl(r_p2, l1, ldir, mu);
return 2;
}
/* math domain error - nan */
return -1;
}
/* point in polygon (keep float and int versions in sync) */
bool isect_point_poly_v2(const float pt[2],
const float verts[][2],
const unsigned int nr,
const bool UNUSED(use_holes))
{
unsigned int i, j;
bool isect = false;
for (i = 0, j = nr - 1; i < nr; j = i++) {
if (((verts[i][1] > pt[1]) != (verts[j][1] > pt[1])) &&
(pt[0] <
(verts[j][0] - verts[i][0]) * (pt[1] - verts[i][1]) / (verts[j][1] - verts[i][1]) +
verts[i][0])) {
isect = !isect;
}
}
return isect;
}
bool isect_point_poly_v2_int(const int pt[2],
const int verts[][2],
const unsigned int nr,
const bool UNUSED(use_holes))
{
unsigned int i, j;
bool isect = false;
for (i = 0, j = nr - 1; i < nr; j = i++) {
if (((verts[i][1] > pt[1]) != (verts[j][1] > pt[1])) &&
(pt[0] <
(verts[j][0] - verts[i][0]) * (pt[1] - verts[i][1]) / (verts[j][1] - verts[i][1]) +
verts[i][0])) {
isect = !isect;
}
}
return isect;
}
/* point in tri */
/* only single direction */
bool isect_point_tri_v2_cw(const float pt[2],
const float v1[2],
const float v2[2],
const float v3[2])
{
if (line_point_side_v2(v1, v2, pt) >= 0.0f) {
if (line_point_side_v2(v2, v3, pt) >= 0.0f) {
if (line_point_side_v2(v3, v1, pt) >= 0.0f) {
return true;
}
}
}
return false;
}
int isect_point_tri_v2(const float pt[2], const float v1[2], const float v2[2], const float v3[2])
{
if (line_point_side_v2(v1, v2, pt) >= 0.0f) {
if (line_point_side_v2(v2, v3, pt) >= 0.0f) {
if (line_point_side_v2(v3, v1, pt) >= 0.0f) {
return 1;
}
}
}
else {
if (!(line_point_side_v2(v2, v3, pt) >= 0.0f)) {
if (!(line_point_side_v2(v3, v1, pt) >= 0.0f)) {
return -1;
}
}
}
return 0;
}
/* point in quad - only convex quads */
int isect_point_quad_v2(
const float pt[2], const float v1[2], const float v2[2], const float v3[2], const float v4[2])
{
if (line_point_side_v2(v1, v2, pt) >= 0.0f) {
if (line_point_side_v2(v2, v3, pt) >= 0.0f) {
if (line_point_side_v2(v3, v4, pt) >= 0.0f) {
if (line_point_side_v2(v4, v1, pt) >= 0.0f) {
return 1;
}
}
}
}
else {
if (!(line_point_side_v2(v2, v3, pt) >= 0.0f)) {
if (!(line_point_side_v2(v3, v4, pt) >= 0.0f)) {
if (!(line_point_side_v2(v4, v1, pt) >= 0.0f)) {
return -1;
}
}
}
}
return 0;
}
/* moved from effect.c
* test if the line starting at p1 ending at p2 intersects the triangle v0..v2
* return non zero if it does
*/
bool isect_line_segment_tri_v3(const float p1[3],
const float p2[3],
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float r_uv[2])
{
float p[3], s[3], d[3], e1[3], e2[3], q[3];
float a, f, u, v;
sub_v3_v3v3(e1, v1, v0);
sub_v3_v3v3(e2, v2, v0);
sub_v3_v3v3(d, p2, p1);
cross_v3_v3v3(p, d, e2);
a = dot_v3v3(e1, p);
if (a == 0.0f) {
return false;
}
f = 1.0f / a;
sub_v3_v3v3(s, p1, v0);
u = f * dot_v3v3(s, p);
if ((u < 0.0f) || (u > 1.0f)) {
return false;
}
cross_v3_v3v3(q, s, e1);
v = f * dot_v3v3(d, q);
if ((v < 0.0f) || ((u + v) > 1.0f)) {
return false;
}
*r_lambda = f * dot_v3v3(e2, q);
if ((*r_lambda < 0.0f) || (*r_lambda > 1.0f)) {
return false;
}
if (r_uv) {
r_uv[0] = u;
r_uv[1] = v;
}
return true;
}
/* like isect_line_segment_tri_v3, but allows epsilon tolerance around triangle */
bool isect_line_segment_tri_epsilon_v3(const float p1[3],
const float p2[3],
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float r_uv[2],
const float epsilon)
{
float p[3], s[3], d[3], e1[3], e2[3], q[3];
float a, f, u, v;
sub_v3_v3v3(e1, v1, v0);
sub_v3_v3v3(e2, v2, v0);
sub_v3_v3v3(d, p2, p1);
cross_v3_v3v3(p, d, e2);
a = dot_v3v3(e1, p);
if (a == 0.0f) {
return false;
}
f = 1.0f / a;
sub_v3_v3v3(s, p1, v0);
u = f * dot_v3v3(s, p);
if ((u < -epsilon) || (u > 1.0f + epsilon)) {
return false;
}
cross_v3_v3v3(q, s, e1);
v = f * dot_v3v3(d, q);
if ((v < -epsilon) || ((u + v) > 1.0f + epsilon)) {
return false;
}
*r_lambda = f * dot_v3v3(e2, q);
if ((*r_lambda < 0.0f) || (*r_lambda > 1.0f)) {
return false;
}
if (r_uv) {
r_uv[0] = u;
r_uv[1] = v;
}
return true;
}
/* moved from effect.c
* test if the ray starting at p1 going in d direction intersects the triangle v0..v2
* return non zero if it does
*/
bool isect_ray_tri_v3(const float ray_origin[3],
const float ray_direction[3],
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float r_uv[2])
{
/* note: these values were 0.000001 in 2.4x but for projection snapping on
* a human head (1BU == 1m), subsurf level 2, this gave many errors - campbell */
const float epsilon = 0.00000001f;
float p[3], s[3], e1[3], e2[3], q[3];
float a, f, u, v;
sub_v3_v3v3(e1, v1, v0);
sub_v3_v3v3(e2, v2, v0);
cross_v3_v3v3(p, ray_direction, e2);
a = dot_v3v3(e1, p);
if ((a > -epsilon) && (a < epsilon)) {
return false;
}
f = 1.0f / a;
sub_v3_v3v3(s, ray_origin, v0);
u = f * dot_v3v3(s, p);
if ((u < 0.0f) || (u > 1.0f)) {
return false;
}
cross_v3_v3v3(q, s, e1);
v = f * dot_v3v3(ray_direction, q);
if ((v < 0.0f) || ((u + v) > 1.0f)) {
return false;
}
*r_lambda = f * dot_v3v3(e2, q);
if ((*r_lambda < 0.0f)) {
return false;
}
if (r_uv) {
r_uv[0] = u;
r_uv[1] = v;
}
return true;
}
/**
* if clip is nonzero, will only return true if lambda is >= 0.0
* (i.e. intersection point is along positive \a ray_direction)
*
* \note #line_plane_factor_v3() shares logic.
*/
bool isect_ray_plane_v3(const float ray_origin[3],
const float ray_direction[3],
const float plane[4],
float *r_lambda,
const bool clip)
{
float h[3], plane_co[3];
float dot;
dot = dot_v3v3(plane, ray_direction);
if (dot == 0.0f) {
return false;
}
mul_v3_v3fl(plane_co, plane, (-plane[3] / len_squared_v3(plane)));
sub_v3_v3v3(h, ray_origin, plane_co);
*r_lambda = -dot_v3v3(plane, h) / dot;
if (clip && (*r_lambda < 0.0f)) {
return false;
}
return true;
}
bool isect_ray_tri_epsilon_v3(const float ray_origin[3],
const float ray_direction[3],
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float r_uv[2],
const float epsilon)
{
float p[3], s[3], e1[3], e2[3], q[3];
float a, f, u, v;
sub_v3_v3v3(e1, v1, v0);
sub_v3_v3v3(e2, v2, v0);
cross_v3_v3v3(p, ray_direction, e2);
a = dot_v3v3(e1, p);
if (a == 0.0f) {
return false;
}
f = 1.0f / a;
sub_v3_v3v3(s, ray_origin, v0);
u = f * dot_v3v3(s, p);
if ((u < -epsilon) || (u > 1.0f + epsilon)) {
return false;
}
cross_v3_v3v3(q, s, e1);
v = f * dot_v3v3(ray_direction, q);
if ((v < -epsilon) || ((u + v) > 1.0f + epsilon)) {
return false;
}
*r_lambda = f * dot_v3v3(e2, q);
if ((*r_lambda < 0.0f)) {
return false;
}
if (r_uv) {
r_uv[0] = u;
r_uv[1] = v;
}
return true;
}
void isect_ray_tri_watertight_v3_precalc(struct IsectRayPrecalc *isect_precalc,
const float ray_direction[3])
{
float inv_dir_z;
/* Calculate dimension where the ray direction is maximal. */
int kz = axis_dominant_v3_single(ray_direction);
int kx = (kz != 2) ? (kz + 1) : 0;
int ky = (kx != 2) ? (kx + 1) : 0;
/* Swap kx and ky dimensions to preserve winding direction of triangles. */
if (ray_direction[kz] < 0.0f) {
SWAP(int, kx, ky);
}
/* Calculate the shear constants. */
inv_dir_z = 1.0f / ray_direction[kz];
isect_precalc->sx = ray_direction[kx] * inv_dir_z;
isect_precalc->sy = ray_direction[ky] * inv_dir_z;
isect_precalc->sz = inv_dir_z;
/* Store the dimensions. */
isect_precalc->kx = kx;
isect_precalc->ky = ky;
isect_precalc->kz = kz;
}
bool isect_ray_tri_watertight_v3(const float ray_origin[3],
const struct IsectRayPrecalc *isect_precalc,
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float r_uv[2])
{
const int kx = isect_precalc->kx;
const int ky = isect_precalc->ky;
const int kz = isect_precalc->kz;
const float sx = isect_precalc->sx;
const float sy = isect_precalc->sy;
const float sz = isect_precalc->sz;
/* Calculate vertices relative to ray origin. */
const float a[3] = {v0[0] - ray_origin[0], v0[1] - ray_origin[1], v0[2] - ray_origin[2]};
const float b[3] = {v1[0] - ray_origin[0], v1[1] - ray_origin[1], v1[2] - ray_origin[2]};
const float c[3] = {v2[0] - ray_origin[0], v2[1] - ray_origin[1], v2[2] - ray_origin[2]};
const float a_kx = a[kx], a_ky = a[ky], a_kz = a[kz];
const float b_kx = b[kx], b_ky = b[ky], b_kz = b[kz];
const float c_kx = c[kx], c_ky = c[ky], c_kz = c[kz];
/* Perform shear and scale of vertices. */
const float ax = a_kx - sx * a_kz;
const float ay = a_ky - sy * a_kz;
const float bx = b_kx - sx * b_kz;
const float by = b_ky - sy * b_kz;
const float cx = c_kx - sx * c_kz;
const float cy = c_ky - sy * c_kz;
/* Calculate scaled barycentric coordinates. */
const float u = cx * by - cy * bx;
const float v = ax * cy - ay * cx;
const float w = bx * ay - by * ax;
float det;
if ((u < 0.0f || v < 0.0f || w < 0.0f) && (u > 0.0f || v > 0.0f || w > 0.0f)) {
return false;
}
/* Calculate determinant. */
det = u + v + w;
if (UNLIKELY(det == 0.0f || !isfinite(det))) {
return false;
}
/* Calculate scaled z-coordinates of vertices and use them to calculate
* the hit distance.
*/
const int sign_det = (float_as_int(det) & (int)0x80000000);
const float t = (u * a_kz + v * b_kz + w * c_kz) * sz;
const float sign_t = xor_fl(t, sign_det);
if ((sign_t < 0.0f)
/* Differ from Cycles, don't read r_lambda's original value
* otherwise we won't match any of the other intersect functions here...
* which would be confusing. */
#if 0
|| (sign_T > *r_lambda * xor_signmask(det, sign_mask))
#endif
) {
return false;
}
/* Normalize u, v and t. */
const float inv_det = 1.0f / det;
if (r_uv) {
r_uv[0] = u * inv_det;
r_uv[1] = v * inv_det;
}
*r_lambda = t * inv_det;
return true;
}
bool isect_ray_tri_watertight_v3_simple(const float ray_origin[3],
const float ray_direction[3],
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float r_uv[2])
{
struct IsectRayPrecalc isect_precalc;
isect_ray_tri_watertight_v3_precalc(&isect_precalc, ray_direction);
return isect_ray_tri_watertight_v3(ray_origin, &isect_precalc, v0, v1, v2, r_lambda, r_uv);
}
#if 0 /* UNUSED */
/**
* A version of #isect_ray_tri_v3 which takes a threshold argument
* so rays slightly outside the triangle to be considered as intersecting.
*/
bool isect_ray_tri_threshold_v3(const float ray_origin[3],
const float ray_direction[3],
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float r_uv[2],
const float threshold)
{
const float epsilon = 0.00000001f;
float p[3], s[3], e1[3], e2[3], q[3];
float a, f, u, v;
float du, dv;
sub_v3_v3v3(e1, v1, v0);
sub_v3_v3v3(e2, v2, v0);
cross_v3_v3v3(p, ray_direction, e2);
a = dot_v3v3(e1, p);
if ((a > -epsilon) && (a < epsilon)) {
return false;
}
f = 1.0f / a;
sub_v3_v3v3(s, ray_origin, v0);
cross_v3_v3v3(q, s, e1);
*r_lambda = f * dot_v3v3(e2, q);
if ((*r_lambda < 0.0f)) {
return false;
}
u = f * dot_v3v3(s, p);
v = f * dot_v3v3(ray_direction, q);
if (u > 0 && v > 0 && u + v > 1) {
float t = (u + v - 1) / 2;
du = u - t;
dv = v - t;
}
else {
if (u < 0) {
du = u;
}
else if (u > 1) {
du = u - 1;
}
else {
du = 0.0f;
}
if (v < 0) {
dv = v;
}
else if (v > 1) {
dv = v - 1;
}
else {
dv = 0.0f;
}
}
mul_v3_fl(e1, du);
mul_v3_fl(e2, dv);
if (len_squared_v3(e1) + len_squared_v3(e2) > threshold * threshold) {
return false;
}
if (r_uv) {
r_uv[0] = u;
r_uv[1] = v;
}
return true;
}
#endif
bool isect_ray_seg_v2(const float ray_origin[2],
const float ray_direction[2],
const float v0[2],
const float v1[2],
float *r_lambda,
float *r_u)
{
float v0_local[2], v1_local[2];
sub_v2_v2v2(v0_local, v0, ray_origin);
sub_v2_v2v2(v1_local, v1, ray_origin);
float s10[2];
float det;
sub_v2_v2v2(s10, v1_local, v0_local);
det = cross_v2v2(ray_direction, s10);
if (det != 0.0f) {
const float v = cross_v2v2(v0_local, v1_local);
const float p[2] = {(ray_direction[0] * v) / det, (ray_direction[1] * v) / det};
const float t = (dot_v2v2(p, ray_direction) / dot_v2v2(ray_direction, ray_direction));
if ((t >= 0.0f) == 0) {
return false;
}
float h[2];
sub_v2_v2v2(h, v1_local, p);
const float u = (dot_v2v2(s10, h) / dot_v2v2(s10, s10));
if ((u >= 0.0f && u <= 1.0f) == 0) {
return false;
}
if (r_lambda) {
*r_lambda = t;
}
if (r_u) {
*r_u = u;
}
return true;
}
return false;
}
bool isect_ray_line_v3(const float ray_origin[3],
const float ray_direction[3],
const float v0[3],
const float v1[3],
float *r_lambda)
{
float a[3], t[3], n[3];
sub_v3_v3v3(a, v1, v0);
sub_v3_v3v3(t, v0, ray_origin);
cross_v3_v3v3(n, a, ray_direction);
const float nlen = len_squared_v3(n);
if (nlen == 0.0f) {
/* the lines are parallel.*/
return false;
}
float c[3], cray[3];
sub_v3_v3v3(c, n, t);
cross_v3_v3v3(cray, c, ray_direction);
*r_lambda = dot_v3v3(cray, n) / nlen;
return true;
}
/**
* Check if a point is behind all planes.
*/
bool isect_point_planes_v3(float (*planes)[4], int totplane, const float p[3])
{
int i;
for (i = 0; i < totplane; i++) {
if (plane_point_side_v3(planes[i], p) > 0.0f) {
return false;
}
}
return true;
}
/**
* Check if a point is in front all planes.
* Same as isect_point_planes_v3 but with planes facing the opposite direction.
*/
bool isect_point_planes_v3_negated(const float (*planes)[4], const int totplane, const float p[3])
{
for (int i = 0; i < totplane; i++) {
if (plane_point_side_v3(planes[i], p) <= 0.0f) {
return false;
}
}
return true;
}
/**
* Intersect line/plane.
*
* \param r_isect_co: The intersection point.
* \param l1: The first point of the line.
* \param l2: The second point of the line.
* \param plane_co: A point on the plane to intersect with.
* \param plane_no: The direction of the plane (does not need to be normalized).
*
* \note #line_plane_factor_v3() shares logic.
*/
bool isect_line_plane_v3(float r_isect_co[3],
const float l1[3],
const float l2[3],
const float plane_co[3],
const float plane_no[3])
{
float u[3], h[3];
float dot;
sub_v3_v3v3(u, l2, l1);
sub_v3_v3v3(h, l1, plane_co);
dot = dot_v3v3(plane_no, u);
if (fabsf(dot) > FLT_EPSILON) {
float lambda = -dot_v3v3(plane_no, h) / dot;
madd_v3_v3v3fl(r_isect_co, l1, u, lambda);
return true;
}
/* The segment is parallel to plane */
return false;
}
/**
* Intersect three planes, return the point where all 3 meet.
* See Graphics Gems 1 pg 305
*
* \param plane_a, plane_b, plane_c: Planes.
* \param r_isect_co: The resulting intersection point.
*/
bool isect_plane_plane_plane_v3(const float plane_a[4],
const float plane_b[4],
const float plane_c[4],
float r_isect_co[3])
{
float det;
det = determinant_m3(UNPACK3(plane_a), UNPACK3(plane_b), UNPACK3(plane_c));
if (det != 0.0f) {
float tmp[3];
/* (plane_b.xyz.cross(plane_c.xyz) * -plane_a[3] +
* plane_c.xyz.cross(plane_a.xyz) * -plane_b[3] +
* plane_a.xyz.cross(plane_b.xyz) * -plane_c[3]) / det; */
cross_v3_v3v3(tmp, plane_c, plane_b);
mul_v3_v3fl(r_isect_co, tmp, plane_a[3]);
cross_v3_v3v3(tmp, plane_a, plane_c);
madd_v3_v3fl(r_isect_co, tmp, plane_b[3]);
cross_v3_v3v3(tmp, plane_b, plane_a);
madd_v3_v3fl(r_isect_co, tmp, plane_c[3]);
mul_v3_fl(r_isect_co, 1.0f / det);
return true;
}
return false;
}
/**
* Intersect two planes, return a point on the intersection and a vector
* that runs on the direction of the intersection.
* \note this is a slightly reduced version of #isect_plane_plane_plane_v3
*
* \param plane_a, plane_b: Planes.
* \param r_isect_co: The resulting intersection point.
* \param r_isect_no: The resulting vector of the intersection.
*
* \note \a r_isect_no isn't unit length.
*/
bool isect_plane_plane_v3(const float plane_a[4],
const float plane_b[4],
float r_isect_co[3],
float r_isect_no[3])
{
float det, plane_c[3];
/* direction is simply the cross product */
cross_v3_v3v3(plane_c, plane_a, plane_b);
/* in this case we don't need to use 'determinant_m3' */
det = len_squared_v3(plane_c);
if (det != 0.0f) {
float tmp[3];
/* (plane_b.xyz.cross(plane_c.xyz) * -plane_a[3] +
* plane_c.xyz.cross(plane_a.xyz) * -plane_b[3]) / det; */
cross_v3_v3v3(tmp, plane_c, plane_b);
mul_v3_v3fl(r_isect_co, tmp, plane_a[3]);
cross_v3_v3v3(tmp, plane_a, plane_c);
madd_v3_v3fl(r_isect_co, tmp, plane_b[3]);
mul_v3_fl(r_isect_co, 1.0f / det);
copy_v3_v3(r_isect_no, plane_c);
return true;
}
return false;
}
/**
* Intersect all planes, calling `callback_fn` for each point that intersects
* 3 of the planes that isn't outside any of the other planes.
*
* This can be thought of as calculating a convex-hull from an array of planes.
*
* \param eps_coplanar: Epsilon for testing if two planes are aligned (co-planar).
* \param eps_isect: Epsilon for testing of a point is behind any of the planes.
*
* \warning As complexity is a little under `O(N^3)`, this is only suitable for small arrays.
*
* \note This function could be optimized by some spatial structure.
*/
bool isect_planes_v3_fn(
const float planes[][4],
const int planes_len,
const float eps_coplanar,
const float eps_isect,
void (*callback_fn)(const float co[3], int i, int j, int k, void *user_data),
void *user_data)
{
bool found = false;
float n1n2[3], n2n3[3], n3n1[3];
for (int i = 0; i < planes_len; i++) {
const float *n1 = planes[i];
for (int j = i + 1; j < planes_len; j++) {
const float *n2 = planes[j];
cross_v3_v3v3(n1n2, n1, n2);
if (len_squared_v3(n1n2) <= eps_coplanar) {
continue;
}
for (int k = j + 1; k < planes_len; k++) {
const float *n3 = planes[k];
cross_v3_v3v3(n2n3, n2, n3);
if (len_squared_v3(n2n3) <= eps_coplanar) {
continue;
}
cross_v3_v3v3(n3n1, n3, n1);
if (len_squared_v3(n3n1) <= eps_coplanar) {
continue;
}
const float quotient = -dot_v3v3(n1, n2n3);
if (fabsf(quotient) < eps_coplanar) {
continue;
}
const float co_test[3] = {
((n2n3[0] * n1[3]) + (n3n1[0] * n2[3]) + (n1n2[0] * n3[3])) / quotient,
((n2n3[1] * n1[3]) + (n3n1[1] * n2[3]) + (n1n2[1] * n3[3])) / quotient,
((n2n3[2] * n1[3]) + (n3n1[2] * n2[3]) + (n1n2[2] * n3[3])) / quotient,
};
int i_test;
for (i_test = 0; i_test < planes_len; i_test++) {
const float *np_test = planes[i_test];
if (((dot_v3v3(np_test, co_test) + np_test[3]) > eps_isect)) {
/* For low epsilon values the point could intersect its own plane. */
if (!ELEM(i_test, i, j, k)) {
break;
}
}
}
if (i_test == planes_len) { /* ok */
callback_fn(co_test, i, j, k, user_data);
found = true;
}
}
}
}
return found;
}
/**
* Intersect two triangles.
*
* \param r_i1, r_i2: Retrieve the overlapping edge between the 2 triangles.
* \param r_tri_a_edge_isect_count: Indicates how many edges in the first triangle are intersected.
* \return true when the triangles intersect.
*
* \note If it exists, \a r_i1 will be a point on the edge of the 1st triangle.
* \note intersections between coplanar triangles are currently undetected.
*/
bool isect_tri_tri_v3_ex(const float tri_a[3][3],
const float tri_b[3][3],
float r_i1[3],
float r_i2[3],
int *r_tri_a_edge_isect_count)
{
struct {
/* Factor that indicates the position of the intersection point on the line
* that intersects the planes of the triangles. */
float min, max;
/* Intersection point location. */
float loc[2][3];
} range[2];
float side[2][3];
double ba[3], bc[3], plane_a[4], plane_b[4];
*r_tri_a_edge_isect_count = 0;
sub_v3db_v3fl_v3fl(ba, tri_a[0], tri_a[1]);
sub_v3db_v3fl_v3fl(bc, tri_a[2], tri_a[1]);
cross_v3_v3v3_db(plane_a, ba, bc);
plane_a[3] = -dot_v3db_v3fl(plane_a, tri_a[1]);
side[1][0] = (float)(dot_v3db_v3fl(plane_a, tri_b[0]) + plane_a[3]);
side[1][1] = (float)(dot_v3db_v3fl(plane_a, tri_b[1]) + plane_a[3]);
side[1][2] = (float)(dot_v3db_v3fl(plane_a, tri_b[2]) + plane_a[3]);
if (!side[1][0] && !side[1][1] && !side[1][2]) {
/* Coplanar case is not supported. */
return false;
}
if ((side[1][0] && side[1][1] && side[1][2]) && (side[1][0] < 0.0f) == (side[1][1] < 0.0f) &&
(side[1][0] < 0.0f) == (side[1][2] < 0.0f)) {
/* All vertices of the 2nd triangle are positioned on the same side to the
* plane defined by the 1st triangle. */
return false;
}
sub_v3db_v3fl_v3fl(ba, tri_b[0], tri_b[1]);
sub_v3db_v3fl_v3fl(bc, tri_b[2], tri_b[1]);
cross_v3_v3v3_db(plane_b, ba, bc);
plane_b[3] = -dot_v3db_v3fl(plane_b, tri_b[1]);
side[0][0] = (float)(dot_v3db_v3fl(plane_b, tri_a[0]) + plane_b[3]);
side[0][1] = (float)(dot_v3db_v3fl(plane_b, tri_a[1]) + plane_b[3]);
side[0][2] = (float)(dot_v3db_v3fl(plane_b, tri_a[2]) + plane_b[3]);
if ((side[0][0] && side[0][1] && side[0][2]) && (side[0][0] < 0.0f) == (side[0][1] < 0.0f) &&
(side[0][0] < 0.0f) == (side[0][2] < 0.0f)) {
/* All vertices of the 1st triangle are positioned on the same side to the
* plane defined by the 2nd triangle. */
return false;
}
/* Direction of the line that intersects the planes of the triangles. */
double isect_dir[3];
cross_v3_v3v3_db(isect_dir, plane_a, plane_b);
for (int i = 0; i < 2; i++) {
const float(*tri)[3] = i == 0 ? tri_a : tri_b;
/* Rearrange the triangle so that the vertex that is alone on one side
* of the plane is located at index 1. */
int tri_i[3];
if ((side[i][0] && side[i][1]) && (side[i][0] < 0.0f) == (side[i][1] < 0.0f)) {
tri_i[0] = 1;
tri_i[1] = 2;
tri_i[2] = 0;
}
else if ((side[i][1] && side[i][2]) && (side[i][1] < 0.0f) == (side[i][2] < 0.0f)) {
tri_i[0] = 2;
tri_i[1] = 0;
tri_i[2] = 1;
}
else {
tri_i[0] = 0;
tri_i[1] = 1;
tri_i[2] = 2;
}
double dot_b = dot_v3db_v3fl(isect_dir, tri[tri_i[1]]);
float sidec = side[i][tri_i[1]];
if (sidec) {
double dot_a = dot_v3db_v3fl(isect_dir, tri[tri_i[0]]);
double dot_c = dot_v3db_v3fl(isect_dir, tri[tri_i[2]]);
float fac0 = sidec / (sidec - side[i][tri_i[0]]);
float fac1 = sidec / (sidec - side[i][tri_i[2]]);
double offset0 = fac0 * (dot_a - dot_b);
double offset1 = fac1 * (dot_c - dot_b);
if (offset0 > offset1) {
/* Sort min max. */
SWAP(double, offset0, offset1);
SWAP(float, fac0, fac1);
SWAP(int, tri_i[0], tri_i[2]);
}
range[i].min = (float)(dot_b + offset0);
range[i].max = (float)(dot_b + offset1);
interp_v3_v3v3(range[i].loc[0], tri[tri_i[1]], tri[tri_i[0]], fac0);
interp_v3_v3v3(range[i].loc[1], tri[tri_i[1]], tri[tri_i[2]], fac1);
}
else {
range[i].min = range[i].max = (float)dot_b;
copy_v3_v3(range[i].loc[0], tri[tri_i[1]]);
copy_v3_v3(range[i].loc[1], tri[tri_i[1]]);
}
}
if ((range[0].max > range[1].min) && (range[0].min < range[1].max)) {
/* The triangles intersect because they overlap on the intersection line.
* Now identify the two points of intersection that are in the middle to get the actual
* intersection between the triangles. (B--C from A--B--C--D) */
if (range[0].min >= range[1].min) {
copy_v3_v3(r_i1, range[0].loc[0]);
if (range[0].max <= range[1].max) {
copy_v3_v3(r_i2, range[0].loc[1]);
*r_tri_a_edge_isect_count = 2;
}
else {
copy_v3_v3(r_i2, range[1].loc[1]);
*r_tri_a_edge_isect_count = 1;
}
}
else {
if (range[0].max <= range[1].max) {
copy_v3_v3(r_i1, range[0].loc[1]);
copy_v3_v3(r_i2, range[1].loc[0]);
*r_tri_a_edge_isect_count = 1;
}
else {
copy_v3_v3(r_i1, range[1].loc[0]);
copy_v3_v3(r_i2, range[1].loc[1]);
}
}
return true;
}
return false;
}
bool isect_tri_tri_v3(const float t_a0[3],
const float t_a1[3],
const float t_a2[3],
const float t_b0[3],
const float t_b1[3],
const float t_b2[3],
float r_i1[3],
float r_i2[3])
{
float tri_a[3][3], tri_b[3][3];
int dummy;
copy_v3_v3(tri_a[0], t_a0);
copy_v3_v3(tri_a[1], t_a1);
copy_v3_v3(tri_a[2], t_a2);
copy_v3_v3(tri_b[0], t_b0);
copy_v3_v3(tri_b[1], t_b1);
copy_v3_v3(tri_b[2], t_b2);
return isect_tri_tri_v3_ex(tri_a, tri_b, r_i1, r_i2, &dummy);
}
/* -------------------------------------------------------------------- */
/** \name Tri-Tri Intersect 2D
*
* "Fast and Robust Triangle-Triangle Overlap Test
* Using Orientation Predicates" P. Guigue - O. Devillers
* Journal of Graphics Tools, 8(1), 2003.
*
* \{ */
static bool isect_tri_tri_v2_impl_vert(const float t_a0[2],
const float t_a1[2],
const float t_a2[2],
const float t_b0[2],
const float t_b1[2],
const float t_b2[2])
{
if (line_point_side_v2(t_b2, t_b0, t_a1) >= 0.0f) {
if (line_point_side_v2(t_b2, t_b1, t_a1) <= 0.0f) {
if (line_point_side_v2(t_a0, t_b0, t_a1) > 0.0f) {
if (line_point_side_v2(t_a0, t_b1, t_a1) <= 0.0f) {
return 1;
}
return 0;
}
if (line_point_side_v2(t_a0, t_b0, t_a2) >= 0.0f) {
if (line_point_side_v2(t_a1, t_a2, t_b0) >= 0.0f) {
return 1;
}
return 0;
}
return 0;
}
if (line_point_side_v2(t_a0, t_b1, t_a1) <= 0.0f) {
if (line_point_side_v2(t_b2, t_b1, t_a2) <= 0.0f) {
if (line_point_side_v2(t_a1, t_a2, t_b1) >= 0.0f) {
return 1;
}
return 0;
}
return 0;
}
return 0;
}
if (line_point_side_v2(t_b2, t_b0, t_a2) >= 0.0f) {
if (line_point_side_v2(t_a1, t_a2, t_b2) >= 0.0f) {
if (line_point_side_v2(t_a0, t_b0, t_a2) >= 0.0f) {
return 1;
}
return 0;
}
if (line_point_side_v2(t_a1, t_a2, t_b1) >= 0.0f) {
if (line_point_side_v2(t_b2, t_a2, t_b1) >= 0.0f) {
return 1;
}
return 0;
}
return 0;
}
return 0;
}
static bool isect_tri_tri_v2_impl_edge(const float t_a0[2],
const float t_a1[2],
const float t_a2[2],
const float t_b0[2],
const float t_b1[2],
const float t_b2[2])
{
UNUSED_VARS(t_b1);
if (line_point_side_v2(t_b2, t_b0, t_a1) >= 0.0f) {
if (line_point_side_v2(t_a0, t_b0, t_a1) >= 0.0f) {
if (line_point_side_v2(t_a0, t_a1, t_b2) >= 0.0f) {
return 1;
}
return 0;
}
if (line_point_side_v2(t_a1, t_a2, t_b0) >= 0.0f) {
if (line_point_side_v2(t_a2, t_a0, t_b0) >= 0.0f) {
return 1;
}
return 0;
}
return 0;
}
if (line_point_side_v2(t_b2, t_b0, t_a2) >= 0.0f) {
if (line_point_side_v2(t_a0, t_b0, t_a2) >= 0.0f) {
if (line_point_side_v2(t_a0, t_a2, t_b2) >= 0.0f) {
return 1;
}
if (line_point_side_v2(t_a1, t_a2, t_b2) >= 0.0f) {
return 1;
}
return 0;
}
return 0;
}
return 0;
}
static int isect_tri_tri_impl_ccw_v2(const float t_a0[2],
const float t_a1[2],
const float t_a2[2],
const float t_b0[2],
const float t_b1[2],
const float t_b2[2])
{
if (line_point_side_v2(t_b0, t_b1, t_a0) >= 0.0f) {
if (line_point_side_v2(t_b1, t_b2, t_a0) >= 0.0f) {
if (line_point_side_v2(t_b2, t_b0, t_a0) >= 0.0f) {
return 1;
}
return isect_tri_tri_v2_impl_edge(t_a0, t_a1, t_a2, t_b0, t_b1, t_b2);
}
if (line_point_side_v2(t_b2, t_b0, t_a0) >= 0.0f) {
return isect_tri_tri_v2_impl_edge(t_a0, t_a1, t_a2, t_b2, t_b0, t_b1);
}
return isect_tri_tri_v2_impl_vert(t_a0, t_a1, t_a2, t_b0, t_b1, t_b2);
}
if (line_point_side_v2(t_b1, t_b2, t_a0) >= 0.0f) {
if (line_point_side_v2(t_b2, t_b0, t_a0) >= 0.0f) {
return isect_tri_tri_v2_impl_edge(t_a0, t_a1, t_a2, t_b1, t_b2, t_b0);
}
return isect_tri_tri_v2_impl_vert(t_a0, t_a1, t_a2, t_b1, t_b2, t_b0);
}
return isect_tri_tri_v2_impl_vert(t_a0, t_a1, t_a2, t_b2, t_b0, t_b1);
}
bool isect_tri_tri_v2(const float t_a0[2],
const float t_a1[2],
const float t_a2[2],
const float t_b0[2],
const float t_b1[2],
const float t_b2[2])
{
if (line_point_side_v2(t_a0, t_a1, t_a2) < 0.0f) {
if (line_point_side_v2(t_b0, t_b1, t_b2) < 0.0f) {
return isect_tri_tri_impl_ccw_v2(t_a0, t_a2, t_a1, t_b0, t_b2, t_b1);
}
return isect_tri_tri_impl_ccw_v2(t_a0, t_a2, t_a1, t_b0, t_b1, t_b2);
}
if (line_point_side_v2(t_b0, t_b1, t_b2) < 0.0f) {
return isect_tri_tri_impl_ccw_v2(t_a0, t_a1, t_a2, t_b0, t_b2, t_b1);
}
return isect_tri_tri_impl_ccw_v2(t_a0, t_a1, t_a2, t_b0, t_b1, t_b2);
}
/** \} */
/* Adapted from the paper by Kasper Fauerby */
/* "Improved Collision detection and Response" */
static bool getLowestRoot(
const float a, const float b, const float c, const float maxR, float *root)
{
/* Check if a solution exists */
const float determinant = b * b - 4.0f * a * c;
/* If determinant is negative it means no solutions. */
if (determinant >= 0.0f) {
/* calculate the two roots: (if determinant == 0 then
* x1==x2 but lets disregard that slight optimization) */
const float sqrtD = sqrtf(determinant);
float r1 = (-b - sqrtD) / (2.0f * a);
float r2 = (-b + sqrtD) / (2.0f * a);
/* Sort so x1 <= x2 */
if (r1 > r2) {
SWAP(float, r1, r2);
}
/* Get lowest root: */
if (r1 > 0.0f && r1 < maxR) {
*root = r1;
return true;
}
/* It is possible that we want x2 - this can happen */
/* if x1 < 0 */
if (r2 > 0.0f && r2 < maxR) {
*root = r2;
return true;
}
}
/* No (valid) solutions */
return false;
}
/**
* Checks status of an AABB in relation to a list of planes.
*
* \returns intersection type:
* - ISECT_AABB_PLANE_BEHIND_ONE (0): AABB is completely behind at least 1 plane;
* - ISECT_AABB_PLANE_CROSS_ANY (1): AABB intersects at least 1 plane;
* - ISECT_AABB_PLANE_IN_FRONT_ALL (2): AABB is completely in front of all planes;
*/
int isect_aabb_planes_v3(const float (*planes)[4],
const int totplane,
const float bbmin[3],
const float bbmax[3])
{
int ret = ISECT_AABB_PLANE_IN_FRONT_ALL;
float bb_near[3], bb_far[3];
for (int i = 0; i < totplane; i++) {
aabb_get_near_far_from_plane(planes[i], bbmin, bbmax, bb_near, bb_far);
if (plane_point_side_v3(planes[i], bb_far) < 0.0f) {
return ISECT_AABB_PLANE_BEHIND_ANY;
}
if ((ret != ISECT_AABB_PLANE_CROSS_ANY) && (plane_point_side_v3(planes[i], bb_near) < 0.0f)) {
ret = ISECT_AABB_PLANE_CROSS_ANY;
}
}
return ret;
}
bool isect_sweeping_sphere_tri_v3(const float p1[3],
const float p2[3],
const float radius,
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda,
float ipoint[3])
{
float e1[3], e2[3], e3[3], point[3], vel[3], /*dist[3],*/ nor[3], temp[3], bv[3];
float a, b, c, d, e, x, y, z, radius2 = radius * radius;
float elen2, edotv, edotbv, nordotv;
float newLambda;
bool found_by_sweep = false;
sub_v3_v3v3(e1, v1, v0);
sub_v3_v3v3(e2, v2, v0);
sub_v3_v3v3(vel, p2, p1);
/*---test plane of tri---*/
cross_v3_v3v3(nor, e1, e2);
normalize_v3(nor);
/* flip normal */
if (dot_v3v3(nor, vel) > 0.0f) {
negate_v3(nor);
}
a = dot_v3v3(p1, nor) - dot_v3v3(v0, nor);
nordotv = dot_v3v3(nor, vel);
if (fabsf(nordotv) < 0.000001f) {
if (fabsf(a) >= radius) {
return false;
}
}
else {
float t0 = (-a + radius) / nordotv;
float t1 = (-a - radius) / nordotv;
if (t0 > t1) {
SWAP(float, t0, t1);
}
if (t0 > 1.0f || t1 < 0.0f) {
return false;
}
/* clamp to [0, 1] */
CLAMP(t0, 0.0f, 1.0f);
CLAMP(t1, 0.0f, 1.0f);
/*---test inside of tri---*/
/* plane intersection point */
point[0] = p1[0] + vel[0] * t0 - nor[0] * radius;
point[1] = p1[1] + vel[1] * t0 - nor[1] * radius;
point[2] = p1[2] + vel[2] * t0 - nor[2] * radius;
/* is the point in the tri? */
a = dot_v3v3(e1, e1);
b = dot_v3v3(e1, e2);
c = dot_v3v3(e2, e2);
sub_v3_v3v3(temp, point, v0);
d = dot_v3v3(temp, e1);
e = dot_v3v3(temp, e2);
x = d * c - e * b;
y = e * a - d * b;
z = x + y - (a * c - b * b);
if (z <= 0.0f && (x >= 0.0f && y >= 0.0f)) {
//(((unsigned int)z)& ~(((unsigned int)x)|((unsigned int)y))) & 0x80000000) {
*r_lambda = t0;
copy_v3_v3(ipoint, point);
return true;
}
}
*r_lambda = 1.0f;
/*---test points---*/
a = dot_v3v3(vel, vel);
/*v0*/
sub_v3_v3v3(temp, p1, v0);
b = 2.0f * dot_v3v3(vel, temp);
c = dot_v3v3(temp, temp) - radius2;
if (getLowestRoot(a, b, c, *r_lambda, r_lambda)) {
copy_v3_v3(ipoint, v0);
found_by_sweep = true;
}
/*v1*/
sub_v3_v3v3(temp, p1, v1);
b = 2.0f * dot_v3v3(vel, temp);
c = dot_v3v3(temp, temp) - radius2;
if (getLowestRoot(a, b, c, *r_lambda, r_lambda)) {
copy_v3_v3(ipoint, v1);
found_by_sweep = true;
}
/*v2*/
sub_v3_v3v3(temp, p1, v2);
b = 2.0f * dot_v3v3(vel, temp);
c = dot_v3v3(temp, temp) - radius2;
if (getLowestRoot(a, b, c, *r_lambda, r_lambda)) {
copy_v3_v3(ipoint, v2);
found_by_sweep = true;
}
/*---test edges---*/
sub_v3_v3v3(e3, v2, v1); /* wasn't yet calculated */
/*e1*/
sub_v3_v3v3(bv, v0, p1);
elen2 = dot_v3v3(e1, e1);
edotv = dot_v3v3(e1, vel);
edotbv = dot_v3v3(e1, bv);
a = elen2 * (-dot_v3v3(vel, vel)) + edotv * edotv;
b = 2.0f * (elen2 * dot_v3v3(vel, bv) - edotv * edotbv);
c = elen2 * (radius2 - dot_v3v3(bv, bv)) + edotbv * edotbv;
if (getLowestRoot(a, b, c, *r_lambda, &newLambda)) {
e = (edotv * newLambda - edotbv) / elen2;
if (e >= 0.0f && e <= 1.0f) {
*r_lambda = newLambda;
copy_v3_v3(ipoint, e1);
mul_v3_fl(ipoint, e);
add_v3_v3(ipoint, v0);
found_by_sweep = true;
}
}
/*e2*/
/*bv is same*/
elen2 = dot_v3v3(e2, e2);
edotv = dot_v3v3(e2, vel);
edotbv = dot_v3v3(e2, bv);
a = elen2 * (-dot_v3v3(vel, vel)) + edotv * edotv;
b = 2.0f * (elen2 * dot_v3v3(vel, bv) - edotv * edotbv);
c = elen2 * (radius2 - dot_v3v3(bv, bv)) + edotbv * edotbv;
if (getLowestRoot(a, b, c, *r_lambda, &newLambda)) {
e = (edotv * newLambda - edotbv) / elen2;
if (e >= 0.0f && e <= 1.0f) {
*r_lambda = newLambda;
copy_v3_v3(ipoint, e2);
mul_v3_fl(ipoint, e);
add_v3_v3(ipoint, v0);
found_by_sweep = true;
}
}
/*e3*/
/* sub_v3_v3v3(bv, v0, p1); */ /* UNUSED */
/* elen2 = dot_v3v3(e1, e1); */ /* UNUSED */
/* edotv = dot_v3v3(e1, vel); */ /* UNUSED */
/* edotbv = dot_v3v3(e1, bv); */ /* UNUSED */
sub_v3_v3v3(bv, v1, p1);
elen2 = dot_v3v3(e3, e3);
edotv = dot_v3v3(e3, vel);
edotbv = dot_v3v3(e3, bv);
a = elen2 * (-dot_v3v3(vel, vel)) + edotv * edotv;
b = 2.0f * (elen2 * dot_v3v3(vel, bv) - edotv * edotbv);
c = elen2 * (radius2 - dot_v3v3(bv, bv)) + edotbv * edotbv;
if (getLowestRoot(a, b, c, *r_lambda, &newLambda)) {
e = (edotv * newLambda - edotbv) / elen2;
if (e >= 0.0f && e <= 1.0f) {
*r_lambda = newLambda;
copy_v3_v3(ipoint, e3);
mul_v3_fl(ipoint, e);
add_v3_v3(ipoint, v1);
found_by_sweep = true;
}
}
return found_by_sweep;
}
bool isect_axial_line_segment_tri_v3(const int axis,
const float p1[3],
const float p2[3],
const float v0[3],
const float v1[3],
const float v2[3],
float *r_lambda)
{
const float epsilon = 0.000001f;
float p[3], e1[3], e2[3];
float u, v, f;
int a0 = axis, a1 = (axis + 1) % 3, a2 = (axis + 2) % 3;
sub_v3_v3v3(e1, v1, v0);
sub_v3_v3v3(e2, v2, v0);
sub_v3_v3v3(p, v0, p1);
f = (e2[a1] * e1[a2] - e2[a2] * e1[a1]);
if ((f > -epsilon) && (f < epsilon)) {
return false;
}
v = (p[a2] * e1[a1] - p[a1] * e1[a2]) / f;
if ((v < 0.0f) || (v > 1.0f)) {
return false;
}
f = e1[a1];
if ((f > -epsilon) && (f < epsilon)) {
f = e1[a2];
if ((f > -epsilon) && (f < epsilon)) {
return false;
}
u = (-p[a2] - v * e2[a2]) / f;
}
else {
u = (-p[a1] - v * e2[a1]) / f;
}
if ((u < 0.0f) || ((u + v) > 1.0f)) {
return false;
}
*r_lambda = (p[a0] + u * e1[a0] + v * e2[a0]) / (p2[a0] - p1[a0]);
if ((*r_lambda < 0.0f) || (*r_lambda > 1.0f)) {
return false;
}
return true;
}
/**
* \return The number of point of interests
* 0 - lines are collinear
* 1 - lines are coplanar, i1 is set to intersection
* 2 - i1 and i2 are the nearest points on line 1 (v1, v2) and line 2 (v3, v4) respectively
*/
int isect_line_line_epsilon_v3(const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3],
float r_i1[3],
float r_i2[3],
const float epsilon)
{
float a[3], b[3], c[3], ab[3], cb[3];
float d, div;
sub_v3_v3v3(c, v3, v1);
sub_v3_v3v3(a, v2, v1);
sub_v3_v3v3(b, v4, v3);
cross_v3_v3v3(ab, a, b);
d = dot_v3v3(c, ab);
div = dot_v3v3(ab, ab);
/* important not to use an epsilon here, see: T45919 */
/* test zero length line */
if (UNLIKELY(div == 0.0f)) {
return 0;
}
/* test if the two lines are coplanar */
if (UNLIKELY(fabsf(d) <= epsilon)) {
cross_v3_v3v3(cb, c, b);
mul_v3_fl(a, dot_v3v3(cb, ab) / div);
add_v3_v3v3(r_i1, v1, a);
copy_v3_v3(r_i2, r_i1);
return 1; /* one intersection only */
}
/* if not */
float n[3], t[3];
float v3t[3], v4t[3];
sub_v3_v3v3(t, v1, v3);
/* offset between both plane where the lines lies */
cross_v3_v3v3(n, a, b);
project_v3_v3v3(t, t, n);
/* for the first line, offset the second line until it is coplanar */
add_v3_v3v3(v3t, v3, t);
add_v3_v3v3(v4t, v4, t);
sub_v3_v3v3(c, v3t, v1);
sub_v3_v3v3(a, v2, v1);
sub_v3_v3v3(b, v4t, v3t);
cross_v3_v3v3(ab, a, b);
cross_v3_v3v3(cb, c, b);
mul_v3_fl(a, dot_v3v3(cb, ab) / dot_v3v3(ab, ab));
add_v3_v3v3(r_i1, v1, a);
/* for the second line, just subtract the offset from the first intersection point */
sub_v3_v3v3(r_i2, r_i1, t);
return 2; /* two nearest points */
}
int isect_line_line_v3(const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3],
float r_i1[3],
float r_i2[3])
{
const float epsilon = 0.000001f;
return isect_line_line_epsilon_v3(v1, v2, v3, v4, r_i1, r_i2, epsilon);
}
/**
* Intersection point strictly between the two lines
* \return false when no intersection is found.
*/
bool isect_line_line_strict_v3(const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3],
float vi[3],
float *r_lambda)
{
const float epsilon = 0.000001f;
float a[3], b[3], c[3], ab[3], cb[3], ca[3];
float d, div;
sub_v3_v3v3(c, v3, v1);
sub_v3_v3v3(a, v2, v1);
sub_v3_v3v3(b, v4, v3);
cross_v3_v3v3(ab, a, b);
d = dot_v3v3(c, ab);
div = dot_v3v3(ab, ab);
/* important not to use an epsilon here, see: T45919 */
/* test zero length line */
if (UNLIKELY(div == 0.0f)) {
return false;
}
/* test if the two lines are coplanar */
if (UNLIKELY(fabsf(d) < epsilon)) {
return false;
}
float f1, f2;
cross_v3_v3v3(cb, c, b);
cross_v3_v3v3(ca, c, a);
f1 = dot_v3v3(cb, ab) / div;
f2 = dot_v3v3(ca, ab) / div;
if (f1 >= 0 && f1 <= 1 && f2 >= 0 && f2 <= 1) {
mul_v3_fl(a, f1);
add_v3_v3v3(vi, v1, a);
if (r_lambda) {
*r_lambda = f1;
}
return true; /* intersection found */
}
return false;
}
/**
* Check if two rays are not parallel and returns a factor that indicates
* the distance from \a ray_origin_b to the closest point on ray-a to ray-b.
*
* \note Neither directions need to be normalized.
*/
bool isect_ray_ray_epsilon_v3(const float ray_origin_a[3],
const float ray_direction_a[3],
const float ray_origin_b[3],
const float ray_direction_b[3],
const float epsilon,
float *r_lambda_a,
float *r_lambda_b)
{
BLI_assert(r_lambda_a || r_lambda_b);
float n[3];
cross_v3_v3v3(n, ray_direction_b, ray_direction_a);
const float nlen = len_squared_v3(n);
/* `nlen` is the square of the area formed by the two vectors. */
if (UNLIKELY(nlen < epsilon)) {
/* The lines are parallel. */
return false;
}
float t[3], c[3], cray[3];
sub_v3_v3v3(t, ray_origin_b, ray_origin_a);
sub_v3_v3v3(c, n, t);
if (r_lambda_a != NULL) {
cross_v3_v3v3(cray, c, ray_direction_b);
*r_lambda_a = dot_v3v3(cray, n) / nlen;
}
if (r_lambda_b != NULL) {
cross_v3_v3v3(cray, c, ray_direction_a);
*r_lambda_b = dot_v3v3(cray, n) / nlen;
}
return true;
}
bool isect_ray_ray_v3(const float ray_origin_a[3],
const float ray_direction_a[3],
const float ray_origin_b[3],
const float ray_direction_b[3],
float *r_lambda_a,
float *r_lambda_b)
{
return isect_ray_ray_epsilon_v3(ray_origin_a,
ray_direction_a,
ray_origin_b,
ray_direction_b,
FLT_MIN,
r_lambda_a,
r_lambda_b);
}
bool isect_aabb_aabb_v3(const float min1[3],
const float max1[3],
const float min2[3],
const float max2[3])
{
return (min1[0] < max2[0] && min1[1] < max2[1] && min1[2] < max2[2] && min2[0] < max1[0] &&
min2[1] < max1[1] && min2[2] < max1[2]);
}
void isect_ray_aabb_v3_precalc(struct IsectRayAABB_Precalc *data,
const float ray_origin[3],
const float ray_direction[3])
{
copy_v3_v3(data->ray_origin, ray_origin);
data->ray_inv_dir[0] = 1.0f / ray_direction[0];
data->ray_inv_dir[1] = 1.0f / ray_direction[1];
data->ray_inv_dir[2] = 1.0f / ray_direction[2];
data->sign[0] = data->ray_inv_dir[0] < 0.0f;
data->sign[1] = data->ray_inv_dir[1] < 0.0f;
data->sign[2] = data->ray_inv_dir[2] < 0.0f;
}
/* Adapted from http://www.gamedev.net/community/forums/topic.asp?topic_id=459973 */
bool isect_ray_aabb_v3(const struct IsectRayAABB_Precalc *data,
const float bb_min[3],
const float bb_max[3],
float *tmin_out)
{
float bbox[2][3];
copy_v3_v3(bbox[0], bb_min);
copy_v3_v3(bbox[1], bb_max);
float tmin = (bbox[data->sign[0]][0] - data->ray_origin[0]) * data->ray_inv_dir[0];
float tmax = (bbox[1 - data->sign[0]][0] - data->ray_origin[0]) * data->ray_inv_dir[0];
const float tymin = (bbox[data->sign[1]][1] - data->ray_origin[1]) * data->ray_inv_dir[1];
const float tymax = (bbox[1 - data->sign[1]][1] - data->ray_origin[1]) * data->ray_inv_dir[1];
if ((tmin > tymax) || (tymin > tmax)) {
return false;
}
if (tymin > tmin) {
tmin = tymin;
}
if (tymax < tmax) {
tmax = tymax;
}
const float tzmin = (bbox[data->sign[2]][2] - data->ray_origin[2]) * data->ray_inv_dir[2];
const float tzmax = (bbox[1 - data->sign[2]][2] - data->ray_origin[2]) * data->ray_inv_dir[2];
if ((tmin > tzmax) || (tzmin > tmax)) {
return false;
}
if (tzmin > tmin) {
tmin = tzmin;
}
/* Note: tmax does not need to be updated since we don't use it
* keeping this here for future reference - jwilkins */
// if (tzmax < tmax) tmax = tzmax;
if (tmin_out) {
(*tmin_out) = tmin;
}
return true;
}
/**
* Test a bounding box (AABB) for ray intersection.
* Assumes the ray is already local to the boundbox space.
*
* \note \a direction should be normalized
* if you intend to use the \a tmin or \a tmax distance results!
*/
bool isect_ray_aabb_v3_simple(const float orig[3],
const float dir[3],
const float bb_min[3],
const float bb_max[3],
float *tmin,
float *tmax)
{
double t[6];
float hit_dist[2];
const double invdirx = (dir[0] > 1e-35f || dir[0] < -1e-35f) ? 1.0 / (double)dir[0] : DBL_MAX;
const double invdiry = (dir[1] > 1e-35f || dir[1] < -1e-35f) ? 1.0 / (double)dir[1] : DBL_MAX;
const double invdirz = (dir[2] > 1e-35f || dir[2] < -1e-35f) ? 1.0 / (double)dir[2] : DBL_MAX;
t[0] = (double)(bb_min[0] - orig[0]) * invdirx;
t[1] = (double)(bb_max[0] - orig[0]) * invdirx;
t[2] = (double)(bb_min[1] - orig[1]) * invdiry;
t[3] = (double)(bb_max[1] - orig[1]) * invdiry;
t[4] = (double)(bb_min[2] - orig[2]) * invdirz;
t[5] = (double)(bb_max[2] - orig[2]) * invdirz;
hit_dist[0] = (float)fmax(fmax(fmin(t[0], t[1]), fmin(t[2], t[3])), fmin(t[4], t[5]));
hit_dist[1] = (float)fmin(fmin(fmax(t[0], t[1]), fmax(t[2], t[3])), fmax(t[4], t[5]));
if ((hit_dist[1] < 0.0f || hit_dist[0] > hit_dist[1])) {
return false;
}
if (tmin) {
*tmin = hit_dist[0];
}
if (tmax) {
*tmax = hit_dist[1];
}
return true;
}
float closest_to_ray_v3(float r_close[3],
const float p[3],
const float ray_orig[3],
const float ray_dir[3])
{
float h[3], lambda;
sub_v3_v3v3(h, p, ray_orig);
lambda = dot_v3v3(ray_dir, h) / dot_v3v3(ray_dir, ray_dir);
madd_v3_v3v3fl(r_close, ray_orig, ray_dir, lambda);
return lambda;
}
/**
* Find closest point to p on line through (l1, l2) and return lambda,
* where (0 <= lambda <= 1) when cp is in the line segment (l1, l2).
*/
float closest_to_line_v3(float r_close[3], const float p[3], const float l1[3], const float l2[3])
{
float u[3];
sub_v3_v3v3(u, l2, l1);
return closest_to_ray_v3(r_close, p, l1, u);
}
float closest_to_line_v2(float r_close[2], const float p[2], const float l1[2], const float l2[2])
{
float h[2], u[2], lambda, denom;
sub_v2_v2v2(u, l2, l1);
sub_v2_v2v2(h, p, l1);
denom = dot_v2v2(u, u);
if (denom == 0.0f) {
r_close[0] = l1[0];
r_close[1] = l1[1];
return 0.0f;
}
lambda = dot_v2v2(u, h) / denom;
r_close[0] = l1[0] + u[0] * lambda;
r_close[1] = l1[1] + u[1] * lambda;
return lambda;
}
double closest_to_line_v2_db(double r_close[2],
const double p[2],
const double l1[2],
const double l2[2])
{
double h[2], u[2], lambda, denom;
sub_v2_v2v2_db(u, l2, l1);
sub_v2_v2v2_db(h, p, l1);
denom = dot_v2v2_db(u, u);
if (denom == 0.0) {
r_close[0] = l1[0];
r_close[1] = l1[1];
return 0.0;
}
lambda = dot_v2v2_db(u, h) / denom;
r_close[0] = l1[0] + u[0] * lambda;
r_close[1] = l1[1] + u[1] * lambda;
return lambda;
}
float ray_point_factor_v3_ex(const float p[3],
const float ray_origin[3],
const float ray_direction[3],
const float epsilon,
const float fallback)
{
float p_relative[3];
sub_v3_v3v3(p_relative, p, ray_origin);
const float dot = len_squared_v3(ray_direction);
return (dot > epsilon) ? (dot_v3v3(ray_direction, p_relative) / dot) : fallback;
}
float ray_point_factor_v3(const float p[3],
const float ray_origin[3],
const float ray_direction[3])
{
return ray_point_factor_v3_ex(p, ray_origin, ray_direction, 0.0f, 0.0f);
}
/**
* A simplified version of #closest_to_line_v3
* we only need to return the ``lambda``
*
* \param epsilon: avoid approaching divide-by-zero.
* Passing a zero will just check for nonzero division.
*/
float line_point_factor_v3_ex(const float p[3],
const float l1[3],
const float l2[3],
const float epsilon,
const float fallback)
{
float h[3], u[3];
float dot;
sub_v3_v3v3(u, l2, l1);
sub_v3_v3v3(h, p, l1);
/* better check for zero */
dot = len_squared_v3(u);
return (dot > epsilon) ? (dot_v3v3(u, h) / dot) : fallback;
}
float line_point_factor_v3(const float p[3], const float l1[3], const float l2[3])
{
return line_point_factor_v3_ex(p, l1, l2, 0.0f, 0.0f);
}
float line_point_factor_v2_ex(const float p[2],
const float l1[2],
const float l2[2],
const float epsilon,
const float fallback)
{
float h[2], u[2];
float dot;
sub_v2_v2v2(u, l2, l1);
sub_v2_v2v2(h, p, l1);
/* better check for zero */
dot = len_squared_v2(u);
return (dot > epsilon) ? (dot_v2v2(u, h) / dot) : fallback;
}
float line_point_factor_v2(const float p[2], const float l1[2], const float l2[2])
{
return line_point_factor_v2_ex(p, l1, l2, 0.0f, 0.0f);
}
/**
* \note #isect_line_plane_v3() shares logic
*/
float line_plane_factor_v3(const float plane_co[3],
const float plane_no[3],
const float l1[3],
const float l2[3])
{
float u[3], h[3];
float dot;
sub_v3_v3v3(u, l2, l1);
sub_v3_v3v3(h, l1, plane_co);
dot = dot_v3v3(plane_no, u);
return (dot != 0.0f) ? -dot_v3v3(plane_no, h) / dot : 0.0f;
}
/**
* Ensure the distance between these points is no greater than 'dist'.
* If it is, scale them both into the center.
*/
void limit_dist_v3(float v1[3], float v2[3], const float dist)
{
const float dist_old = len_v3v3(v1, v2);
if (dist_old > dist) {
float v1_old[3];
float v2_old[3];
float fac = (dist / dist_old) * 0.5f;
copy_v3_v3(v1_old, v1);
copy_v3_v3(v2_old, v2);
interp_v3_v3v3(v1, v1_old, v2_old, 0.5f - fac);
interp_v3_v3v3(v2, v1_old, v2_old, 0.5f + fac);
}
}
/*
* x1,y2
* | \
* | \ .(a,b)
* | \
* x1,y1-- x2,y1
*/
int isect_point_tri_v2_int(
const int x1, const int y1, const int x2, const int y2, const int a, const int b)
{
float v1[2], v2[2], v3[2], p[2];
v1[0] = (float)x1;
v1[1] = (float)y1;
v2[0] = (float)x1;
v2[1] = (float)y2;
v3[0] = (float)x2;
v3[1] = (float)y1;
p[0] = (float)a;
p[1] = (float)b;
return isect_point_tri_v2(p, v1, v2, v3);
}
static bool point_in_slice(const float p[3],
const float v1[3],
const float l1[3],
const float l2[3])
{
/*
* what is a slice ?
* some maths:
* a line including (l1, l2) and a point not on the line
* define a subset of R3 delimited by planes parallel to the line and orthogonal
* to the (point --> line) distance vector, one plane on the line one on the point,
* the room inside usually is rather small compared to R3 though still infinite
* useful for restricting (speeding up) searches
* e.g. all points of triangular prism are within the intersection of 3 'slices'
* another trivial case : cube
* but see a 'spat' which is a deformed cube with paired parallel planes needs only 3 slices too
*/
float h, rp[3], cp[3], q[3];
closest_to_line_v3(cp, v1, l1, l2);
sub_v3_v3v3(q, cp, v1);
sub_v3_v3v3(rp, p, v1);
h = dot_v3v3(q, rp) / dot_v3v3(q, q);
/* note: when 'h' is nan/-nan, this check returns false
* without explicit check - covering the degenerate case */
return (h >= 0.0f && h <= 1.0f);
}
/* adult sister defining the slice planes by the origin and the normal
* NOTE |normal| may not be 1 but defining the thickness of the slice */
static bool point_in_slice_as(const float p[3], const float origin[3], const float normal[3])
{
float h, rp[3];
sub_v3_v3v3(rp, p, origin);
h = dot_v3v3(normal, rp) / dot_v3v3(normal, normal);
if (h < 0.0f || h > 1.0f) {
return false;
}
return true;
}
bool point_in_slice_seg(float p[3], float l1[3], float l2[3])
{
float normal[3];
sub_v3_v3v3(normal, l2, l1);
return point_in_slice_as(p, l1, normal);
}
bool isect_point_tri_prism_v3(const float p[3],
const float v1[3],
const float v2[3],
const float v3[3])
{
if (!point_in_slice(p, v1, v2, v3)) {
return false;
}
if (!point_in_slice(p, v2, v3, v1)) {
return false;
}
if (!point_in_slice(p, v3, v1, v2)) {
return false;
}
return true;
}
/**
* \param r_isect_co: The point \a p projected onto the triangle.
* \return True when \a p is inside the triangle.
* \note Its up to the caller to check the distance between \a p and \a r_vi
* against an error margin.
*/
bool isect_point_tri_v3(
const float p[3], const float v1[3], const float v2[3], const float v3[3], float r_isect_co[3])
{
if (isect_point_tri_prism_v3(p, v1, v2, v3)) {
float plane[4];
float no[3];
/* Could use normal_tri_v3, but doesn't have to be unit-length */
cross_tri_v3(no, v1, v2, v3);
BLI_assert(len_squared_v3(no) != 0.0f);
plane_from_point_normal_v3(plane, v1, no);
closest_to_plane_v3(r_isect_co, plane, p);
return true;
}
return false;
}
bool clip_segment_v3_plane(
const float p1[3], const float p2[3], const float plane[4], float r_p1[3], float r_p2[3])
{
float dp[3], div;
sub_v3_v3v3(dp, p2, p1);
div = dot_v3v3(dp, plane);
if (div == 0.0f) {
/* parallel */
return true;
}
float t = -plane_point_side_v3(plane, p1);
if (div > 0.0f) {
/* behind plane, completely clipped */
if (t >= div) {
return false;
}
if (t > 0.0f) {
const float p1_copy[3] = {UNPACK3(p1)};
copy_v3_v3(r_p2, p2);
madd_v3_v3v3fl(r_p1, p1_copy, dp, t / div);
return true;
}
}
else {
/* behind plane, completely clipped */
if (t >= 0.0f) {
return false;
}
if (t > div) {
const float p1_copy[3] = {UNPACK3(p1)};
copy_v3_v3(r_p1, p1);
madd_v3_v3v3fl(r_p2, p1_copy, dp, t / div);
return true;
}
}
/* In case input/output values match (above also). */
const float p1_copy[3] = {UNPACK3(p1)};
copy_v3_v3(r_p2, p2);
copy_v3_v3(r_p1, p1_copy);
return true;
}
bool clip_segment_v3_plane_n(const float p1[3],
const float p2[3],
const float plane_array[][4],
const int plane_tot,
float r_p1[3],
float r_p2[3])
{
/* intersect from both directions */
float p1_fac = 0.0f, p2_fac = 1.0f;
float dp[3];
sub_v3_v3v3(dp, p2, p1);
for (int i = 0; i < plane_tot; i++) {
const float *plane = plane_array[i];
const float div = dot_v3v3(dp, plane);
if (div != 0.0f) {
float t = -plane_point_side_v3(plane, p1);
if (div > 0.0f) {
/* clip p1 lower bounds */
if (t >= div) {
return false;
}
if (t > 0.0f) {
t /= div;
if (t > p1_fac) {
p1_fac = t;
if (p1_fac > p2_fac) {
return false;
}
}
}
}
else if (div < 0.0f) {
/* clip p2 upper bounds */
if (t >= 0.0f) {
return false;
}
if (t > div) {
t /= div;
if (t < p2_fac) {
p2_fac = t;
if (p1_fac > p2_fac) {
return false;
}
}
}
}
}
}
/* In case input/output values match. */
const float p1_copy[3] = {UNPACK3(p1)};
madd_v3_v3v3fl(r_p1, p1_copy, dp, p1_fac);
madd_v3_v3v3fl(r_p2, p1_copy, dp, p2_fac);
return true;
}
/****************************** Axis Utils ********************************/
/**
* \brief Normal to x,y matrix
*
* Creates a 3x3 matrix from a normal.
* This matrix can be applied to vectors so their 'z' axis runs along \a normal.
* In practice it means you can use x,y as 2d coords. \see
*
* \param r_mat: The matrix to return.
* \param normal: A unit length vector.
*/
void axis_dominant_v3_to_m3(float r_mat[3][3], const float normal[3])
{
BLI_ASSERT_UNIT_V3(normal);
copy_v3_v3(r_mat[2], normal);
ortho_basis_v3v3_v3(r_mat[0], r_mat[1], r_mat[2]);
BLI_ASSERT_UNIT_V3(r_mat[0]);
BLI_ASSERT_UNIT_V3(r_mat[1]);
transpose_m3(r_mat);
BLI_assert(!is_negative_m3(r_mat));
BLI_assert((fabsf(dot_m3_v3_row_z(r_mat, normal) - 1.0f) < BLI_ASSERT_UNIT_EPSILON) ||
is_zero_v3(normal));
}
/**
* Same as axis_dominant_v3_to_m3, but flips the normal
*/
void axis_dominant_v3_to_m3_negate(float r_mat[3][3], const float normal[3])
{
BLI_ASSERT_UNIT_V3(normal);
negate_v3_v3(r_mat[2], normal);
ortho_basis_v3v3_v3(r_mat[0], r_mat[1], r_mat[2]);
BLI_ASSERT_UNIT_V3(r_mat[0]);
BLI_ASSERT_UNIT_V3(r_mat[1]);
transpose_m3(r_mat);
BLI_assert(!is_negative_m3(r_mat));
BLI_assert((dot_m3_v3_row_z(r_mat, normal) < BLI_ASSERT_UNIT_EPSILON) || is_zero_v3(normal));
}
/****************************** Interpolation ********************************/
static float tri_signed_area(
const float v1[3], const float v2[3], const float v3[3], const int i, const int j)
{
return 0.5f * ((v1[i] - v2[i]) * (v2[j] - v3[j]) + (v1[j] - v2[j]) * (v3[i] - v2[i]));
}
/**
* \return false when degenerate.
*/
static bool barycentric_weights(const float v1[3],
const float v2[3],
const float v3[3],
const float co[3],
const float n[3],
float w[3])
{
float wtot;
int i, j;
axis_dominant_v3(&i, &j, n);
w[0] = tri_signed_area(v2, v3, co, i, j);
w[1] = tri_signed_area(v3, v1, co, i, j);
w[2] = tri_signed_area(v1, v2, co, i, j);
wtot = w[0] + w[1] + w[2];
#ifdef DEBUG /* Avoid floating point exception when debugging. */
if (wtot != 0.0f)
#endif
{
mul_v3_fl(w, 1.0f / wtot);
if (is_finite_v3(w)) {
return true;
}
}
/* Zero area triangle. */
copy_v3_fl(w, 1.0f / 3.0f);
return false;
}
void interp_weights_tri_v3(
float w[3], const float v1[3], const float v2[3], const float v3[3], const float co[3])
{
float n[3];
normal_tri_v3(n, v1, v2, v3);
barycentric_weights(v1, v2, v3, co, n, w);
}
void interp_weights_quad_v3(float w[4],
const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3],
const float co[3])
{
float w2[3];
zero_v4(w);
/* first check for exact match */
if (equals_v3v3(co, v1)) {
w[0] = 1.0f;
}
else if (equals_v3v3(co, v2)) {
w[1] = 1.0f;
}
else if (equals_v3v3(co, v3)) {
w[2] = 1.0f;
}
else if (equals_v3v3(co, v4)) {
w[3] = 1.0f;
}
else {
/* otherwise compute barycentric interpolation weights */
float n1[3], n2[3], n[3];
bool ok;
sub_v3_v3v3(n1, v1, v3);
sub_v3_v3v3(n2, v2, v4);
cross_v3_v3v3(n, n1, n2);
ok = barycentric_weights(v1, v2, v4, co, n, w);
SWAP(float, w[2], w[3]);
if (!ok || (w[0] < 0.0f)) {
/* if w[1] is negative, co is on the other side of the v1-v3 edge,
* so we interpolate using the other triangle */
ok = barycentric_weights(v2, v3, v4, co, n, w2);
if (ok) {
w[0] = 0.0f;
w[1] = w2[0];
w[2] = w2[1];
w[3] = w2[2];
}
}
}
}
/**
* \return
* - 0 if the point is outside of triangle.
* - 1 if the point is inside triangle.
* - 2 if it's on the edge.
*/
int barycentric_inside_triangle_v2(const float w[3])
{
if (IN_RANGE(w[0], 0.0f, 1.0f) && IN_RANGE(w[1], 0.0f, 1.0f) && IN_RANGE(w[2], 0.0f, 1.0f)) {
return 1;
}
if (IN_RANGE_INCL(w[0], 0.0f, 1.0f) && IN_RANGE_INCL(w[1], 0.0f, 1.0f) &&
IN_RANGE_INCL(w[2], 0.0f, 1.0f)) {
return 2;
}
return 0;
}
/**
* \return false for degenerated triangles.
*/
bool barycentric_coords_v2(
const float v1[2], const float v2[2], const float v3[2], const float co[2], float w[3])
{
const float x = co[0], y = co[1];
const float x1 = v1[0], y1 = v1[1];
const float x2 = v2[0], y2 = v2[1];
const float x3 = v3[0], y3 = v3[1];
const float det = (y2 - y3) * (x1 - x3) + (x3 - x2) * (y1 - y3);
#ifdef DEBUG /* Avoid floating point exception when debugging. */
if (det != 0.0f)
#endif
{
w[0] = ((y2 - y3) * (x - x3) + (x3 - x2) * (y - y3)) / det;
w[1] = ((y3 - y1) * (x - x3) + (x1 - x3) * (y - y3)) / det;
w[2] = 1.0f - w[0] - w[1];
if (is_finite_v3(w)) {
return true;
}
}
return false;
}
/**
* \note Using #cross_tri_v2 means locations outside the triangle are correctly weighted.
*
* \note This is *exactly* the same calculation as #resolve_tri_uv_v2,
* although it has double precision and is used for texture baking, so keep both.
*/
void barycentric_weights_v2(
const float v1[2], const float v2[2], const float v3[2], const float co[2], float w[3])
{
float wtot;
w[0] = cross_tri_v2(v2, v3, co);
w[1] = cross_tri_v2(v3, v1, co);
w[2] = cross_tri_v2(v1, v2, co);
wtot = w[0] + w[1] + w[2];
#ifdef DEBUG /* Avoid floating point exception when debugging. */
if (wtot != 0.0f)
#endif
{
mul_v3_fl(w, 1.0f / wtot);
if (is_finite_v3(w)) {
return;
}
}
/* Dummy values for zero area face. */
copy_v3_fl(w, 1.0f / 3.0f);
}
/**
* A version of #barycentric_weights_v2 that doesn't allow negative weights.
* Useful when negative values cause problems and points are only
* ever slightly outside of the triangle.
*/
void barycentric_weights_v2_clamped(
const float v1[2], const float v2[2], const float v3[2], const float co[2], float w[3])
{
float wtot;
w[0] = max_ff(cross_tri_v2(v2, v3, co), 0.0f);
w[1] = max_ff(cross_tri_v2(v3, v1, co), 0.0f);
w[2] = max_ff(cross_tri_v2(v1, v2, co), 0.0f);
wtot = w[0] + w[1] + w[2];
#ifdef DEBUG /* Avoid floating point exception when debugging. */
if (wtot != 0.0f)
#endif
{
mul_v3_fl(w, 1.0f / wtot);
if (is_finite_v3(w)) {
return;
}
}
/* Dummy values for zero area face. */
copy_v3_fl(w, 1.0f / 3.0f);
}
/**
* still use 2D X,Y space but this works for verts transformed by a perspective matrix,
* using their 4th component as a weight
*/
void barycentric_weights_v2_persp(
const float v1[4], const float v2[4], const float v3[4], const float co[2], float w[3])
{
float wtot;
w[0] = cross_tri_v2(v2, v3, co) / v1[3];
w[1] = cross_tri_v2(v3, v1, co) / v2[3];
w[2] = cross_tri_v2(v1, v2, co) / v3[3];
wtot = w[0] + w[1] + w[2];
#ifdef DEBUG /* Avoid floating point exception when debugging. */
if (wtot != 0.0f)
#endif
{
mul_v3_fl(w, 1.0f / wtot);
if (is_finite_v3(w)) {
return;
}
}
/* Dummy values for zero area face. */
copy_v3_fl(w, 1.0f / 3.0f);
}
/**
* same as #barycentric_weights_v2 but works with a quad,
* note: untested for values outside the quad's bounds
* this is #interp_weights_poly_v2 expanded for quads only
*/
void barycentric_weights_v2_quad(const float v1[2],
const float v2[2],
const float v3[2],
const float v4[2],
const float co[2],
float w[4])
{
/* note: fabsf() here is not needed for convex quads (and not used in interp_weights_poly_v2).
* but in the case of concave/bow-tie quads for the mask rasterizer it gives unreliable results
* without adding absf(). If this becomes an issue for more general usage we could have
* this optional or use a different function - Campbell */
#define MEAN_VALUE_HALF_TAN_V2(_area, i1, i2) \
((_area = cross_v2v2(dirs[i1], dirs[i2])) != 0.0f ? \
fabsf(((lens[i1] * lens[i2]) - dot_v2v2(dirs[i1], dirs[i2])) / _area) : \
0.0f)
const float dirs[4][2] = {
{v1[0] - co[0], v1[1] - co[1]},
{v2[0] - co[0], v2[1] - co[1]},
{v3[0] - co[0], v3[1] - co[1]},
{v4[0] - co[0], v4[1] - co[1]},
};
const float lens[4] = {
len_v2(dirs[0]),
len_v2(dirs[1]),
len_v2(dirs[2]),
len_v2(dirs[3]),
};
/* avoid divide by zero */
if (UNLIKELY(lens[0] < FLT_EPSILON)) {
w[0] = 1.0f;
w[1] = w[2] = w[3] = 0.0f;
}
else if (UNLIKELY(lens[1] < FLT_EPSILON)) {
w[1] = 1.0f;
w[0] = w[2] = w[3] = 0.0f;
}
else if (UNLIKELY(lens[2] < FLT_EPSILON)) {
w[2] = 1.0f;
w[0] = w[1] = w[3] = 0.0f;
}
else if (UNLIKELY(lens[3] < FLT_EPSILON)) {
w[3] = 1.0f;
w[0] = w[1] = w[2] = 0.0f;
}
else {
float wtot, area;
/* variable 'area' is just for storage,
* the order its initialized doesn't matter */
#ifdef __clang__
# pragma clang diagnostic push
# pragma clang diagnostic ignored "-Wunsequenced"
#endif
/* inline mean_value_half_tan four times here */
const float t[4] = {
MEAN_VALUE_HALF_TAN_V2(area, 0, 1),
MEAN_VALUE_HALF_TAN_V2(area, 1, 2),
MEAN_VALUE_HALF_TAN_V2(area, 2, 3),
MEAN_VALUE_HALF_TAN_V2(area, 3, 0),
};
#ifdef __clang__
# pragma clang diagnostic pop
#endif
#undef MEAN_VALUE_HALF_TAN_V2
w[0] = (t[3] + t[0]) / lens[0];
w[1] = (t[0] + t[1]) / lens[1];
w[2] = (t[1] + t[2]) / lens[2];
w[3] = (t[2] + t[3]) / lens[3];
wtot = w[0] + w[1] + w[2] + w[3];
#ifdef DEBUG /* Avoid floating point exception when debugging. */
if (wtot != 0.0f)
#endif
{
mul_v4_fl(w, 1.0f / wtot);
if (is_finite_v4(w)) {
return;
}
}
/* Dummy values for zero area face. */
copy_v4_fl(w, 1.0f / 4.0f);
}
}
/* given 2 triangles in 3D space, and a point in relation to the first triangle.
* calculate the location of a point in relation to the second triangle.
* Useful for finding relative positions with geometry */
void transform_point_by_tri_v3(float pt_tar[3],
float const pt_src[3],
const float tri_tar_p1[3],
const float tri_tar_p2[3],
const float tri_tar_p3[3],
const float tri_src_p1[3],
const float tri_src_p2[3],
const float tri_src_p3[3])
{
/* this works by moving the source triangle so its normal is pointing on the Z
* axis where its barycentric weights can be calculated in 2D and its Z offset can
* be re-applied. The weights are applied directly to the targets 3D points and the
* z-depth is used to scale the targets normal as an offset.
* This saves transforming the target into its Z-Up orientation and back
* (which could also work) */
float no_tar[3], no_src[3];
float mat_src[3][3];
float pt_src_xy[3];
float tri_xy_src[3][3];
float w_src[3];
float area_tar, area_src;
float z_ofs_src;
normal_tri_v3(no_tar, tri_tar_p1, tri_tar_p2, tri_tar_p3);
normal_tri_v3(no_src, tri_src_p1, tri_src_p2, tri_src_p3);
axis_dominant_v3_to_m3(mat_src, no_src);
/* make the source tri xy space */
mul_v3_m3v3(pt_src_xy, mat_src, pt_src);
mul_v3_m3v3(tri_xy_src[0], mat_src, tri_src_p1);
mul_v3_m3v3(tri_xy_src[1], mat_src, tri_src_p2);
mul_v3_m3v3(tri_xy_src[2], mat_src, tri_src_p3);
barycentric_weights_v2(tri_xy_src[0], tri_xy_src[1], tri_xy_src[2], pt_src_xy, w_src);
interp_v3_v3v3v3(pt_tar, tri_tar_p1, tri_tar_p2, tri_tar_p3, w_src);
area_tar = sqrtf(area_tri_v3(tri_tar_p1, tri_tar_p2, tri_tar_p3));
area_src = sqrtf(area_tri_v2(tri_xy_src[0], tri_xy_src[1], tri_xy_src[2]));
z_ofs_src = pt_src_xy[2] - tri_xy_src[0][2];
madd_v3_v3v3fl(pt_tar, pt_tar, no_tar, (z_ofs_src / area_src) * area_tar);
}
/**
* Simply re-interpolates,
* assumes p_src is between \a l_src_p1-l_src_p2
*/
void transform_point_by_seg_v3(float p_dst[3],
const float p_src[3],
const float l_dst_p1[3],
const float l_dst_p2[3],
const float l_src_p1[3],
const float l_src_p2[3])
{
float t = line_point_factor_v3(p_src, l_src_p1, l_src_p2);
interp_v3_v3v3(p_dst, l_dst_p1, l_dst_p2, t);
}
/* given an array with some invalid values this function interpolates valid values
* replacing the invalid ones */
int interp_sparse_array(float *array, const int list_size, const float skipval)
{
int found_invalid = 0;
int found_valid = 0;
int i;
for (i = 0; i < list_size; i++) {
if (array[i] == skipval) {
found_invalid = 1;
}
else {
found_valid = 1;
}
}
if (found_valid == 0) {
return -1;
}
if (found_invalid == 0) {
return 0;
}
/* found invalid depths, interpolate */
float valid_last = skipval;
int valid_ofs = 0;
float *array_up = MEM_callocN(sizeof(float) * (size_t)list_size, "interp_sparse_array up");
float *array_down = MEM_callocN(sizeof(float) * (size_t)list_size, "interp_sparse_array up");
int *ofs_tot_up = MEM_callocN(sizeof(int) * (size_t)list_size, "interp_sparse_array tup");
int *ofs_tot_down = MEM_callocN(sizeof(int) * (size_t)list_size, "interp_sparse_array tdown");
for (i = 0; i < list_size; i++) {
if (array[i] == skipval) {
array_up[i] = valid_last;
ofs_tot_up[i] = ++valid_ofs;
}
else {
valid_last = array[i];
valid_ofs = 0;
}
}
valid_last = skipval;
valid_ofs = 0;
for (i = list_size - 1; i >= 0; i--) {
if (array[i] == skipval) {
array_down[i] = valid_last;
ofs_tot_down[i] = ++valid_ofs;
}
else {
valid_last = array[i];
valid_ofs = 0;
}
}
/* now blend */
for (i = 0; i < list_size; i++) {
if (array[i] == skipval) {
if (array_up[i] != skipval && array_down[i] != skipval) {
array[i] = ((array_up[i] * (float)ofs_tot_down[i]) +
(array_down[i] * (float)ofs_tot_up[i])) /
(float)(ofs_tot_down[i] + ofs_tot_up[i]);
}
else if (array_up[i] != skipval) {
array[i] = array_up[i];
}
else if (array_down[i] != skipval) {
array[i] = array_down[i];
}
}
}
MEM_freeN(array_up);
MEM_freeN(array_down);
MEM_freeN(ofs_tot_up);
MEM_freeN(ofs_tot_down);
return 1;
}
/* -------------------------------------------------------------------- */
/** \name interp_weights_poly_v2, v3
* \{ */
#define IS_POINT_IX (1 << 0)
#define IS_SEGMENT_IX (1 << 1)
#define DIR_V3_SET(d_len, va, vb) \
{ \
sub_v3_v3v3((d_len)->dir, va, vb); \
(d_len)->len = len_v3((d_len)->dir); \
} \
(void)0
#define DIR_V2_SET(d_len, va, vb) \
{ \
sub_v2db_v2fl_v2fl((d_len)->dir, va, vb); \
(d_len)->len = len_v2_db((d_len)->dir); \
} \
(void)0
struct Float3_Len {
float dir[3], len;
};
struct Double2_Len {
double dir[2], len;
};
/* Mean value weights - smooth interpolation weights for polygons with
* more than 3 vertices */
static float mean_value_half_tan_v3(const struct Float3_Len *d_curr,
const struct Float3_Len *d_next)
{
float cross[3];
cross_v3_v3v3(cross, d_curr->dir, d_next->dir);
const float area = len_v3(cross);
/* Compare against zero since 'FLT_EPSILON' can be too large, see: T73348. */
if (LIKELY(area != 0.0f)) {
const float dot = dot_v3v3(d_curr->dir, d_next->dir);
const float len = d_curr->len * d_next->len;
const float result = (len - dot) / area;
if (isfinite(result)) {
return result;
}
}
return 0.0f;
}
/**
* Mean value weights - same as #mean_value_half_tan_v3 but for 2D vectors.
*
* \note When interpolating a 2D polygon, a point can be considered "outside"
* the polygon's bounds. Thus, when the point is very distant and the vectors
* have relatively close values, the precision problems are evident since they
* do not indicate a point "inside" the polygon.
* To resolve this, doubles are used.
*/
static double mean_value_half_tan_v2_db(const struct Double2_Len *d_curr,
const struct Double2_Len *d_next)
{
/* Different from the 3d version but still correct. */
const double area = cross_v2v2_db(d_curr->dir, d_next->dir);
/* Compare against zero since 'FLT_EPSILON' can be too large, see: T73348. */
if (LIKELY(area != 0.0)) {
const double dot = dot_v2v2_db(d_curr->dir, d_next->dir);
const double len = d_curr->len * d_next->len;
const double result = (len - dot) / area;
if (isfinite(result)) {
return result;
}
}
return 0.0;
}
void interp_weights_poly_v3(float *w, float v[][3], const int n, const float co[3])
{
/* Before starting to calculate the weight, we need to figure out the floating point precision we
* can expect from the supplied data. */
float max_value = 0;
for (int i = 0; i < n; i++) {
max_value = max_ff(max_value, fabsf(v[i][0] - co[0]));
max_value = max_ff(max_value, fabsf(v[i][1] - co[1]));
max_value = max_ff(max_value, fabsf(v[i][2] - co[2]));
}
/* These to values we derived by empirically testing different values that works for the test
* files in D7772. */
const float eps = 16.0f * FLT_EPSILON * max_value;
const float eps_sq = eps * eps;
const float *v_curr, *v_next;
float ht_prev, ht; /* half tangents */
float totweight = 0.0f;
int i_curr, i_next;
char ix_flag = 0;
struct Float3_Len d_curr, d_next;
/* loop over 'i_next' */
i_curr = n - 1;
i_next = 0;
v_curr = v[i_curr];
v_next = v[i_next];
DIR_V3_SET(&d_curr, v_curr - 3 /* v[n - 2] */, co);
DIR_V3_SET(&d_next, v_curr /* v[n - 1] */, co);
ht_prev = mean_value_half_tan_v3(&d_curr, &d_next);
while (i_next < n) {
/* Mark Mayer et al algorithm that is used here does not operate well if vertex is close
* to borders of face.
* In that case, do simple linear interpolation between the two edge vertices */
/* 'd_next.len' is in fact 'd_curr.len', just avoid copy to begin with */
if (UNLIKELY(d_next.len < eps)) {
ix_flag = IS_POINT_IX;
break;
}
if (UNLIKELY(dist_squared_to_line_segment_v3(co, v_curr, v_next) < eps_sq)) {
ix_flag = IS_SEGMENT_IX;
break;
}
d_curr = d_next;
DIR_V3_SET(&d_next, v_next, co);
ht = mean_value_half_tan_v3(&d_curr, &d_next);
w[i_curr] = (ht_prev + ht) / d_curr.len;
totweight += w[i_curr];
/* step */
i_curr = i_next++;
v_curr = v_next;
v_next = v[i_next];
ht_prev = ht;
}
if (ix_flag) {
memset(w, 0, sizeof(*w) * (size_t)n);
if (ix_flag & IS_POINT_IX) {
w[i_curr] = 1.0f;
}
else {
float fac = line_point_factor_v3(co, v_curr, v_next);
CLAMP(fac, 0.0f, 1.0f);
w[i_curr] = 1.0f - fac;
w[i_next] = fac;
}
}
else {
if (totweight != 0.0f) {
for (i_curr = 0; i_curr < n; i_curr++) {
w[i_curr] /= totweight;
}
}
}
}
void interp_weights_poly_v2(float *w, float v[][2], const int n, const float co[2])
{
/* Before starting to calculate the weight, we need to figure out the floating point precision we
* can expect from the supplied data. */
float max_value = 0;
for (int i = 0; i < n; i++) {
max_value = max_ff(max_value, fabsf(v[i][0] - co[0]));
max_value = max_ff(max_value, fabsf(v[i][1] - co[1]));
}
/* These to values we derived by empirically testing different values that works for the test
* files in D7772. */
const float eps = 16.0f * FLT_EPSILON * max_value;
const float eps_sq = eps * eps;
const float *v_curr, *v_next;
double ht_prev, ht; /* half tangents */
float totweight = 0.0f;
int i_curr, i_next;
char ix_flag = 0;
struct Double2_Len d_curr, d_next;
/* loop over 'i_next' */
i_curr = n - 1;
i_next = 0;
v_curr = v[i_curr];
v_next = v[i_next];
DIR_V2_SET(&d_curr, v_curr - 2 /* v[n - 2] */, co);
DIR_V2_SET(&d_next, v_curr /* v[n - 1] */, co);
ht_prev = mean_value_half_tan_v2_db(&d_curr, &d_next);
while (i_next < n) {
/* Mark Mayer et al algorithm that is used here does not operate well if vertex is close
* to borders of face. In that case,
* do simple linear interpolation between the two edge vertices */
/* 'd_next.len' is in fact 'd_curr.len', just avoid copy to begin with */
if (UNLIKELY(d_next.len < eps)) {
ix_flag = IS_POINT_IX;
break;
}
if (UNLIKELY(dist_squared_to_line_segment_v2(co, v_curr, v_next) < eps_sq)) {
ix_flag = IS_SEGMENT_IX;
break;
}
d_curr = d_next;
DIR_V2_SET(&d_next, v_next, co);
ht = mean_value_half_tan_v2_db(&d_curr, &d_next);
w[i_curr] = (float)((ht_prev + ht) / d_curr.len);
totweight += w[i_curr];
/* step */
i_curr = i_next++;
v_curr = v_next;
v_next = v[i_next];
ht_prev = ht;
}
if (ix_flag) {
memset(w, 0, sizeof(*w) * (size_t)n);
if (ix_flag & IS_POINT_IX) {
w[i_curr] = 1.0f;
}
else {
float fac = line_point_factor_v2(co, v_curr, v_next);
CLAMP(fac, 0.0f, 1.0f);
w[i_curr] = 1.0f - fac;
w[i_next] = fac;
}
}
else {
if (totweight != 0.0f) {
for (i_curr = 0; i_curr < n; i_curr++) {
w[i_curr] /= totweight;
}
}
}
}
#undef IS_POINT_IX
#undef IS_SEGMENT_IX
#undef DIR_V3_SET
#undef DIR_V2_SET
/** \} */
/* (x1, v1)(t1=0)------(x2, v2)(t2=1), 0 (x, v)(t) */
void interp_cubic_v3(float x[3],
float v[3],
const float x1[3],
const float v1[3],
const float x2[3],
const float v2[3],
const float t)
{
float a[3], b[3];
const float t2 = t * t;
const float t3 = t2 * t;
/* cubic interpolation */
a[0] = v1[0] + v2[0] + 2 * (x1[0] - x2[0]);
a[1] = v1[1] + v2[1] + 2 * (x1[1] - x2[1]);
a[2] = v1[2] + v2[2] + 2 * (x1[2] - x2[2]);
b[0] = -2 * v1[0] - v2[0] - 3 * (x1[0] - x2[0]);
b[1] = -2 * v1[1] - v2[1] - 3 * (x1[1] - x2[1]);
b[2] = -2 * v1[2] - v2[2] - 3 * (x1[2] - x2[2]);
x[0] = a[0] * t3 + b[0] * t2 + v1[0] * t + x1[0];
x[1] = a[1] * t3 + b[1] * t2 + v1[1] * t + x1[1];
x[2] = a[2] * t3 + b[2] * t2 + v1[2] * t + x1[2];
v[0] = 3 * a[0] * t2 + 2 * b[0] * t + v1[0];
v[1] = 3 * a[1] * t2 + 2 * b[1] * t + v1[1];
v[2] = 3 * a[2] * t2 + 2 * b[2] * t + v1[2];
}
/* unfortunately internal calculations have to be done at double precision
* to achieve correct/stable results. */
#define IS_ZERO(x) ((x > (-DBL_EPSILON) && x < DBL_EPSILON) ? 1 : 0)
/**
* Barycentric reverse
*
* Compute coordinates (u, v) for point \a st with respect to triangle (\a st0, \a st1, \a st2)
*
* \note same basic result as #barycentric_weights_v2, see its comment for details.
*/
void resolve_tri_uv_v2(
float r_uv[2], const float st[2], const float st0[2], const float st1[2], const float st2[2])
{
/* find UV such that
* t = u * t0 + v * t1 + (1 - u - v) * t2
* u * (t0 - t2) + v * (t1 - t2) = t - t2 */
const double a = st0[0] - st2[0], b = st1[0] - st2[0];
const double c = st0[1] - st2[1], d = st1[1] - st2[1];
const double det = a * d - c * b;
/* det should never be zero since the determinant is the signed ST area of the triangle. */
if (IS_ZERO(det) == 0) {
const double x[2] = {st[0] - st2[0], st[1] - st2[1]};
r_uv[0] = (float)((d * x[0] - b * x[1]) / det);
r_uv[1] = (float)(((-c) * x[0] + a * x[1]) / det);
}
else {
zero_v2(r_uv);
}
}
/**
* Barycentric reverse 3d
*
* Compute coordinates (u, v) for point \a st with respect to triangle (\a st0, \a st1, \a st2)
*/
void resolve_tri_uv_v3(
float r_uv[2], const float st[3], const float st0[3], const float st1[3], const float st2[3])
{
float v0[3], v1[3], v2[3];
double d00, d01, d11, d20, d21, det;
sub_v3_v3v3(v0, st1, st0);
sub_v3_v3v3(v1, st2, st0);
sub_v3_v3v3(v2, st, st0);
d00 = dot_v3v3(v0, v0);
d01 = dot_v3v3(v0, v1);
d11 = dot_v3v3(v1, v1);
d20 = dot_v3v3(v2, v0);
d21 = dot_v3v3(v2, v1);
det = d00 * d11 - d01 * d01;
/* det should never be zero since the determinant is the signed ST area of the triangle. */
if (IS_ZERO(det) == 0) {
float w;
w = (float)((d00 * d21 - d01 * d20) / det);
r_uv[1] = (float)((d11 * d20 - d01 * d21) / det);
r_uv[0] = 1.0f - r_uv[1] - w;
}
else {
zero_v2(r_uv);
}
}
/* bilinear reverse */
void resolve_quad_uv_v2(float r_uv[2],
const float st[2],
const float st0[2],
const float st1[2],
const float st2[2],
const float st3[2])
{
resolve_quad_uv_v2_deriv(r_uv, NULL, st, st0, st1, st2, st3);
}
/* bilinear reverse with derivatives */
void resolve_quad_uv_v2_deriv(float r_uv[2],
float r_deriv[2][2],
const float st[2],
const float st0[2],
const float st1[2],
const float st2[2],
const float st3[2])
{
const double signed_area = (st0[0] * st1[1] - st0[1] * st1[0]) +
(st1[0] * st2[1] - st1[1] * st2[0]) +
(st2[0] * st3[1] - st2[1] * st3[0]) +
(st3[0] * st0[1] - st3[1] * st0[0]);
/* X is 2D cross product (determinant)
* A = (p0 - p) X (p0 - p3)*/
const double a = (st0[0] - st[0]) * (st0[1] - st3[1]) - (st0[1] - st[1]) * (st0[0] - st3[0]);
/* B = ( (p0 - p) X (p1 - p2) + (p1 - p) X (p0 - p3) ) / 2 */
const double b = 0.5 * (double)(((st0[0] - st[0]) * (st1[1] - st2[1]) -
(st0[1] - st[1]) * (st1[0] - st2[0])) +
((st1[0] - st[0]) * (st0[1] - st3[1]) -
(st1[1] - st[1]) * (st0[0] - st3[0])));
/* C = (p1-p) X (p1-p2) */
const double fC = (st1[0] - st[0]) * (st1[1] - st2[1]) - (st1[1] - st[1]) * (st1[0] - st2[0]);
double denom = a - 2 * b + fC;
/* clear outputs */
zero_v2(r_uv);
if (IS_ZERO(denom) != 0) {
const double fDen = a - fC;
if (IS_ZERO(fDen) == 0) {
r_uv[0] = (float)(a / fDen);
}
}
else {
const double desc_sq = b * b - a * fC;
const double desc = sqrt(desc_sq < 0.0 ? 0.0 : desc_sq);
const double s = signed_area > 0 ? (-1.0) : 1.0;
r_uv[0] = (float)(((a - b) + s * desc) / denom);
}
/* find UV such that
* fST = (1-u)(1-v) * ST0 + u * (1-v) * ST1 + u * v * ST2 + (1-u) * v * ST3 */
{
const double denom_s = (1 - r_uv[0]) * (st0[0] - st3[0]) + r_uv[0] * (st1[0] - st2[0]);
const double denom_t = (1 - r_uv[0]) * (st0[1] - st3[1]) + r_uv[0] * (st1[1] - st2[1]);
int i = 0;
denom = denom_s;
if (fabs(denom_s) < fabs(denom_t)) {
i = 1;
denom = denom_t;
}
if (IS_ZERO(denom) == 0) {
r_uv[1] = (float)((double)((1.0f - r_uv[0]) * (st0[i] - st[i]) +
r_uv[0] * (st1[i] - st[i])) /
denom);
}
}
if (r_deriv) {
float tmp1[2], tmp2[2], s[2], t[2];
/* clear outputs */
zero_v2(r_deriv[0]);
zero_v2(r_deriv[1]);
sub_v2_v2v2(tmp1, st1, st0);
sub_v2_v2v2(tmp2, st2, st3);
interp_v2_v2v2(s, tmp1, tmp2, r_uv[1]);
sub_v2_v2v2(tmp1, st3, st0);
sub_v2_v2v2(tmp2, st2, st1);
interp_v2_v2v2(t, tmp1, tmp2, r_uv[0]);
denom = t[0] * s[1] - t[1] * s[0];
if (!IS_ZERO(denom)) {
double inv_denom = 1.0 / denom;
r_deriv[0][0] = (float)((double)-t[1] * inv_denom);
r_deriv[0][1] = (float)((double)t[0] * inv_denom);
r_deriv[1][0] = (float)((double)s[1] * inv_denom);
r_deriv[1][1] = (float)((double)-s[0] * inv_denom);
}
}
}
/* a version of resolve_quad_uv_v2 that only calculates the 'u' */
float resolve_quad_u_v2(const float st[2],
const float st0[2],
const float st1[2],
const float st2[2],
const float st3[2])
{
const double signed_area = (st0[0] * st1[1] - st0[1] * st1[0]) +
(st1[0] * st2[1] - st1[1] * st2[0]) +
(st2[0] * st3[1] - st2[1] * st3[0]) +
(st3[0] * st0[1] - st3[1] * st0[0]);
/* X is 2D cross product (determinant)
* A = (p0 - p) X (p0 - p3)*/
const double a = (st0[0] - st[0]) * (st0[1] - st3[1]) - (st0[1] - st[1]) * (st0[0] - st3[0]);
/* B = ( (p0 - p) X (p1 - p2) + (p1 - p) X (p0 - p3) ) / 2 */
const double b = 0.5 * (double)(((st0[0] - st[0]) * (st1[1] - st2[1]) -
(st0[1] - st[1]) * (st1[0] - st2[0])) +
((st1[0] - st[0]) * (st0[1] - st3[1]) -
(st1[1] - st[1]) * (st0[0] - st3[0])));
/* C = (p1-p) X (p1-p2) */
const double fC = (st1[0] - st[0]) * (st1[1] - st2[1]) - (st1[1] - st[1]) * (st1[0] - st2[0]);
double denom = a - 2 * b + fC;
if (IS_ZERO(denom) != 0) {
const double fDen = a - fC;
if (IS_ZERO(fDen) == 0) {
return (float)(a / fDen);
}
return 0.0f;
}
const double desc_sq = b * b - a * fC;
const double desc = sqrt(desc_sq < 0.0 ? 0.0 : desc_sq);
const double s = signed_area > 0 ? (-1.0) : 1.0;
return (float)(((a - b) + s * desc) / denom);
}
#undef IS_ZERO
/* reverse of the functions above */
void interp_bilinear_quad_v3(float data[4][3], float u, float v, float res[3])
{
float vec[3];
copy_v3_v3(res, data[0]);
mul_v3_fl(res, (1 - u) * (1 - v));
copy_v3_v3(vec, data[1]);
mul_v3_fl(vec, u * (1 - v));
add_v3_v3(res, vec);
copy_v3_v3(vec, data[2]);
mul_v3_fl(vec, u * v);
add_v3_v3(res, vec);
copy_v3_v3(vec, data[3]);
mul_v3_fl(vec, (1 - u) * v);
add_v3_v3(res, vec);
}
void interp_barycentric_tri_v3(float data[3][3], float u, float v, float res[3])
{
float vec[3];
copy_v3_v3(res, data[0]);
mul_v3_fl(res, u);
copy_v3_v3(vec, data[1]);
mul_v3_fl(vec, v);
add_v3_v3(res, vec);
copy_v3_v3(vec, data[2]);
mul_v3_fl(vec, 1.0f - u - v);
add_v3_v3(res, vec);
}
/***************************** View & Projection *****************************/
/**
* Matches `glOrtho` result.
*/
void orthographic_m4(float matrix[4][4],
const float left,
const float right,
const float bottom,
const float top,
const float nearClip,
const float farClip)
{
float Xdelta, Ydelta, Zdelta;
Xdelta = right - left;
Ydelta = top - bottom;
Zdelta = farClip - nearClip;
if (Xdelta == 0.0f || Ydelta == 0.0f || Zdelta == 0.0f) {
return;
}
unit_m4(matrix);
matrix[0][0] = 2.0f / Xdelta;
matrix[3][0] = -(right + left) / Xdelta;
matrix[1][1] = 2.0f / Ydelta;
matrix[3][1] = -(top + bottom) / Ydelta;
matrix[2][2] = -2.0f / Zdelta; /* note: negate Z */
matrix[3][2] = -(farClip + nearClip) / Zdelta;
}
/**
* Matches `glFrustum` result.
*/
void perspective_m4(float mat[4][4],
const float left,
const float right,
const float bottom,
const float top,
const float nearClip,
const float farClip)
{
const float Xdelta = right - left;
const float Ydelta = top - bottom;
const float Zdelta = farClip - nearClip;
if (Xdelta == 0.0f || Ydelta == 0.0f || Zdelta == 0.0f) {
return;
}
mat[0][0] = nearClip * 2.0f / Xdelta;
mat[1][1] = nearClip * 2.0f / Ydelta;
mat[2][0] = (right + left) / Xdelta; /* note: negate Z */
mat[2][1] = (top + bottom) / Ydelta;
mat[2][2] = -(farClip + nearClip) / Zdelta;
mat[2][3] = -1.0f;
mat[3][2] = (-2.0f * nearClip * farClip) / Zdelta;
mat[0][1] = mat[0][2] = mat[0][3] = mat[1][0] = mat[1][2] = mat[1][3] = mat[3][0] = mat[3][1] =
mat[3][3] = 0.0f;
}
void perspective_m4_fov(float mat[4][4],
const float angle_left,
const float angle_right,
const float angle_up,
const float angle_down,
const float nearClip,
const float farClip)
{
const float tan_angle_left = tanf(angle_left);
const float tan_angle_right = tanf(angle_right);
const float tan_angle_bottom = tanf(angle_up);
const float tan_angle_top = tanf(angle_down);
perspective_m4(
mat, tan_angle_left, tan_angle_right, tan_angle_top, tan_angle_bottom, nearClip, farClip);
mat[0][0] /= nearClip;
mat[1][1] /= nearClip;
}
/* translate a matrix created by orthographic_m4 or perspective_m4 in XY coords
* (used to jitter the view) */
void window_translate_m4(float winmat[4][4], float perspmat[4][4], const float x, const float y)
{
if (winmat[2][3] == -1.0f) {
/* in the case of a win-matrix, this means perspective always */
float v1[3];
float v2[3];
float len1, len2;
v1[0] = perspmat[0][0];
v1[1] = perspmat[1][0];
v1[2] = perspmat[2][0];
v2[0] = perspmat[0][1];
v2[1] = perspmat[1][1];
v2[2] = perspmat[2][1];
len1 = (1.0f / len_v3(v1));
len2 = (1.0f / len_v3(v2));
winmat[2][0] -= len1 * winmat[0][0] * x;
winmat[2][1] -= len2 * winmat[1][1] * y;
}
else {
winmat[3][0] += x;
winmat[3][1] += y;
}
}
/**
* Frustum planes extraction from a projection matrix
* (homogeneous 4d vector representations of planes).
*
* plane parameters can be NULL if you do not need them.
*/
void planes_from_projmat(const float mat[4][4],
float left[4],
float right[4],
float top[4],
float bottom[4],
float near[4],
float far[4])
{
/* References:
*
* https://fgiesen.wordpress.com/2012/08/31/frustum-planes-from-the-projection-matrix/
* http://www8.cs.umu.se/kurser/5DV051/HT12/lab/plane_extraction.pdf
*/
int i;
if (left) {
for (i = 4; i--;) {
left[i] = mat[i][3] + mat[i][0];
}
}
if (right) {
for (i = 4; i--;) {
right[i] = mat[i][3] - mat[i][0];
}
}
if (bottom) {
for (i = 4; i--;) {
bottom[i] = mat[i][3] + mat[i][1];
}
}
if (top) {
for (i = 4; i--;) {
top[i] = mat[i][3] - mat[i][1];
}
}
if (near) {
for (i = 4; i--;) {
near[i] = mat[i][3] + mat[i][2];
}
}
if (far) {
for (i = 4; i--;) {
far[i] = mat[i][3] - mat[i][2];
}
}
}
void projmat_dimensions(const float projmat[4][4],
float *r_left,
float *r_right,
float *r_bottom,
float *r_top,
float *r_near,
float *r_far)
{
bool is_persp = projmat[3][3] == 0.0f;
if (is_persp) {
*r_left = (projmat[2][0] - 1.0f) / projmat[0][0];
*r_right = (projmat[2][0] + 1.0f) / projmat[0][0];
*r_bottom = (projmat[2][1] - 1.0f) / projmat[1][1];
*r_top = (projmat[2][1] + 1.0f) / projmat[1][1];
*r_near = projmat[3][2] / (projmat[2][2] - 1.0f);
*r_far = projmat[3][2] / (projmat[2][2] + 1.0f);
}
else {
*r_left = (-projmat[3][0] - 1.0f) / projmat[0][0];
*r_right = (-projmat[3][0] + 1.0f) / projmat[0][0];
*r_bottom = (-projmat[3][1] - 1.0f) / projmat[1][1];
*r_top = (-projmat[3][1] + 1.0f) / projmat[1][1];
*r_near = (projmat[3][2] + 1.0f) / projmat[2][2];
*r_far = (projmat[3][2] - 1.0f) / projmat[2][2];
}
}
void projmat_dimensions_db(const float projmat_fl[4][4],
double *r_left,
double *r_right,
double *r_bottom,
double *r_top,
double *r_near,
double *r_far)
{
double projmat[4][4];
copy_m4d_m4(projmat, projmat_fl);
bool is_persp = projmat[3][3] == 0.0f;
if (is_persp) {
*r_left = (projmat[2][0] - 1.0) / projmat[0][0];
*r_right = (projmat[2][0] + 1.0) / projmat[0][0];
*r_bottom = (projmat[2][1] - 1.0) / projmat[1][1];
*r_top = (projmat[2][1] + 1.0) / projmat[1][1];
*r_near = projmat[3][2] / (projmat[2][2] - 1.0);
*r_far = projmat[3][2] / (projmat[2][2] + 1.0);
}
else {
*r_left = (-projmat[3][0] - 1.0) / projmat[0][0];
*r_right = (-projmat[3][0] + 1.0) / projmat[0][0];
*r_bottom = (-projmat[3][1] - 1.0) / projmat[1][1];
*r_top = (-projmat[3][1] + 1.0) / projmat[1][1];
*r_near = (projmat[3][2] + 1.0) / projmat[2][2];
*r_far = (projmat[3][2] - 1.0) / projmat[2][2];
}
}
/**
* Creates a projection matrix for a small region of the viewport.
*
* \param projmat: Projection Matrix.
* \param win_size: Viewport Size.
* \param x_min, x_max, y_min, y_max: Coordinates of the subregion.
* \return r_projmat: Resulting Projection Matrix.
*/
void projmat_from_subregion(const float projmat[4][4],
const int win_size[2],
const int x_min,
const int x_max,
const int y_min,
const int y_max,
float r_projmat[4][4])
{
float rect_width = (float)(x_max - x_min);
float rect_height = (float)(y_max - y_min);
float x_sca = (float)win_size[0] / rect_width;
float y_sca = (float)win_size[1] / rect_height;
float x_fac = (float)((x_min + x_max) - win_size[0]) / rect_width;
float y_fac = (float)((y_min + y_max) - win_size[1]) / rect_height;
copy_m4_m4(r_projmat, projmat);
r_projmat[0][0] *= x_sca;
r_projmat[1][1] *= y_sca;
if (projmat[3][3] == 0.0f) {
r_projmat[2][0] = r_projmat[2][0] * x_sca + x_fac;
r_projmat[2][1] = r_projmat[2][1] * y_sca + y_fac;
}
else {
r_projmat[3][0] = r_projmat[3][0] * x_sca - x_fac;
r_projmat[3][1] = r_projmat[3][1] * y_sca - y_fac;
}
}
static void i_multmatrix(const float icand[4][4], float mat[4][4])
{
int row, col;
float temp[4][4];
for (row = 0; row < 4; row++) {
for (col = 0; col < 4; col++) {
temp[row][col] = (icand[row][0] * mat[0][col] + icand[row][1] * mat[1][col] +
icand[row][2] * mat[2][col] + icand[row][3] * mat[3][col]);
}
}
copy_m4_m4(mat, temp);
}
void polarview_m4(float mat[4][4], float dist, float azimuth, float incidence, float twist)
{
unit_m4(mat);
translate_m4(mat, 0.0, 0.0, -dist);
rotate_m4(mat, 'Z', -twist);
rotate_m4(mat, 'X', -incidence);
rotate_m4(mat, 'Z', -azimuth);
}
void lookat_m4(
float mat[4][4], float vx, float vy, float vz, float px, float py, float pz, float twist)
{
float sine, cosine, hyp, hyp1, dx, dy, dz;
float mat1[4][4];
unit_m4(mat1);
axis_angle_to_mat4_single(mat, 'Z', -twist);
dx = px - vx;
dy = py - vy;
dz = pz - vz;
hyp = dx * dx + dz * dz; /* hyp squared */
hyp1 = sqrtf(dy * dy + hyp);
hyp = sqrtf(hyp); /* the real hyp */
if (hyp1 != 0.0f) { /* rotate X */
sine = -dy / hyp1;
cosine = hyp / hyp1;
}
else {
sine = 0.0f;
cosine = 1.0f;
}
mat1[1][1] = cosine;
mat1[1][2] = sine;
mat1[2][1] = -sine;
mat1[2][2] = cosine;
i_multmatrix(mat1, mat);
mat1[1][1] = mat1[2][2] = 1.0f; /* be careful here to reinit */
mat1[1][2] = mat1[2][1] = 0.0f; /* those modified by the last */
/* paragraph */
if (hyp != 0.0f) { /* rotate Y */
sine = dx / hyp;
cosine = -dz / hyp;
}
else {
sine = 0.0f;
cosine = 1.0f;
}
mat1[0][0] = cosine;
mat1[0][2] = -sine;
mat1[2][0] = sine;
mat1[2][2] = cosine;
i_multmatrix(mat1, mat);
translate_m4(mat, -vx, -vy, -vz); /* translate viewpoint to origin */
}
int box_clip_bounds_m4(float boundbox[2][3], const float bounds[4], float winmat[4][4])
{
float mat[4][4], vec[4];
int a, fl, flag = -1;
copy_m4_m4(mat, winmat);
for (a = 0; a < 8; a++) {
vec[0] = (a & 1) ? boundbox[0][0] : boundbox[1][0];
vec[1] = (a & 2) ? boundbox[0][1] : boundbox[1][1];
vec[2] = (a & 4) ? boundbox[0][2] : boundbox[1][2];
vec[3] = 1.0;
mul_m4_v4(mat, vec);
fl = 0;
if (bounds) {
if (vec[0] > bounds[1] * vec[3]) {
fl |= 1;
}
if (vec[0] < bounds[0] * vec[3]) {
fl |= 2;
}
if (vec[1] > bounds[3] * vec[3]) {
fl |= 4;
}
if (vec[1] < bounds[2] * vec[3]) {
fl |= 8;
}
}
else {
if (vec[0] < -vec[3]) {
fl |= 1;
}
if (vec[0] > vec[3]) {
fl |= 2;
}
if (vec[1] < -vec[3]) {
fl |= 4;
}
if (vec[1] > vec[3]) {
fl |= 8;
}
}
if (vec[2] < -vec[3]) {
fl |= 16;
}
if (vec[2] > vec[3]) {
fl |= 32;
}
flag &= fl;
if (flag == 0) {
return 0;
}
}
return flag;
}
void box_minmax_bounds_m4(float min[3], float max[3], float boundbox[2][3], float mat[4][4])
{
float mn[3], mx[3], vec[3];
int a;
copy_v3_v3(mn, min);
copy_v3_v3(mx, max);
for (a = 0; a < 8; a++) {
vec[0] = (a & 1) ? boundbox[0][0] : boundbox[1][0];
vec[1] = (a & 2) ? boundbox[0][1] : boundbox[1][1];
vec[2] = (a & 4) ? boundbox[0][2] : boundbox[1][2];
mul_m4_v3(mat, vec);
minmax_v3v3_v3(mn, mx, vec);
}
copy_v3_v3(min, mn);
copy_v3_v3(max, mx);
}
/********************************** Mapping **********************************/
void map_to_tube(float *r_u, float *r_v, const float x, const float y, const float z)
{
float len;
*r_v = (z + 1.0f) / 2.0f;
len = sqrtf(x * x + y * y);
if (len > 0.0f) {
*r_u = (1.0f - (atan2f(x / len, y / len) / (float)M_PI)) / 2.0f;
}
else {
*r_v = *r_u = 0.0f; /* to avoid un-initialized variables */
}
}
void map_to_sphere(float *r_u, float *r_v, const float x, const float y, const float z)
{
float len;
len = sqrtf(x * x + y * y + z * z);
if (len > 0.0f) {
if (UNLIKELY(x == 0.0f && y == 0.0f)) {
*r_u = 0.0f; /* Otherwise domain error. */
}
else {
*r_u = (1.0f - atan2f(x, y) / (float)M_PI) / 2.0f;
}
*r_v = 1.0f - saacos(z / len) / (float)M_PI;
}
else {
*r_v = *r_u = 0.0f; /* to avoid un-initialized variables */
}
}
void map_to_plane_v2_v3v3(float r_co[2], const float co[3], const float no[3])
{
const float target[3] = {0.0f, 0.0f, 1.0f};
float axis[3];
cross_v3_v3v3(axis, no, target);
normalize_v3(axis);
map_to_plane_axis_angle_v2_v3v3fl(r_co, co, axis, angle_normalized_v3v3(no, target));
}
void map_to_plane_axis_angle_v2_v3v3fl(float r_co[2],
const float co[3],
const float axis[3],
const float angle)
{
float tmp[3];
rotate_normalized_v3_v3v3fl(tmp, co, axis, angle);
copy_v2_v2(r_co, tmp);
}
/********************************* Normals **********************************/
void accumulate_vertex_normals_tri_v3(float n1[3],
float n2[3],
float n3[3],
const float f_no[3],
const float co1[3],
const float co2[3],
const float co3[3])
{
float vdiffs[3][3];
const int nverts = 3;
/* compute normalized edge vectors */
sub_v3_v3v3(vdiffs[0], co2, co1);
sub_v3_v3v3(vdiffs[1], co3, co2);
sub_v3_v3v3(vdiffs[2], co1, co3);
normalize_v3(vdiffs[0]);
normalize_v3(vdiffs[1]);
normalize_v3(vdiffs[2]);
/* accumulate angle weighted face normal */
{
float *vn[] = {n1, n2, n3};
const float *prev_edge = vdiffs[nverts - 1];
int i;
for (i = 0; i < nverts; i++) {
const float *cur_edge = vdiffs[i];
const float fac = saacos(-dot_v3v3(cur_edge, prev_edge));
/* accumulate */
madd_v3_v3fl(vn[i], f_no, fac);
prev_edge = cur_edge;
}
}
}
void accumulate_vertex_normals_v3(float n1[3],
float n2[3],
float n3[3],
float n4[3],
const float f_no[3],
const float co1[3],
const float co2[3],
const float co3[3],
const float co4[3])
{
float vdiffs[4][3];
const int nverts = (n4 != NULL && co4 != NULL) ? 4 : 3;
/* compute normalized edge vectors */
sub_v3_v3v3(vdiffs[0], co2, co1);
sub_v3_v3v3(vdiffs[1], co3, co2);
if (nverts == 3) {
sub_v3_v3v3(vdiffs[2], co1, co3);
}
else {
sub_v3_v3v3(vdiffs[2], co4, co3);
sub_v3_v3v3(vdiffs[3], co1, co4);
normalize_v3(vdiffs[3]);
}
normalize_v3(vdiffs[0]);
normalize_v3(vdiffs[1]);
normalize_v3(vdiffs[2]);
/* accumulate angle weighted face normal */
{
float *vn[] = {n1, n2, n3, n4};
const float *prev_edge = vdiffs[nverts - 1];
int i;
for (i = 0; i < nverts; i++) {
const float *cur_edge = vdiffs[i];
const float fac = saacos(-dot_v3v3(cur_edge, prev_edge));
/* accumulate */
madd_v3_v3fl(vn[i], f_no, fac);
prev_edge = cur_edge;
}
}
}
/* Add weighted face normal component into normals of the face vertices.
* Caller must pass pre-allocated vdiffs of nverts length. */
void accumulate_vertex_normals_poly_v3(float **vertnos,
const float polyno[3],
const float **vertcos,
float vdiffs[][3],
const int nverts)
{
int i;
/* calculate normalized edge directions for each edge in the poly */
for (i = 0; i < nverts; i++) {
sub_v3_v3v3(vdiffs[i], vertcos[(i + 1) % nverts], vertcos[i]);
normalize_v3(vdiffs[i]);
}
/* accumulate angle weighted face normal */
{
const float *prev_edge = vdiffs[nverts - 1];
for (i = 0; i < nverts; i++) {
const float *cur_edge = vdiffs[i];
/* calculate angle between the two poly edges incident on
* this vertex */
const float fac = saacos(-dot_v3v3(cur_edge, prev_edge));
/* accumulate */
madd_v3_v3fl(vertnos[i], polyno, fac);
prev_edge = cur_edge;
}
}
}
/********************************* Tangents **********************************/
void tangent_from_uv_v3(const float uv1[2],
const float uv2[2],
const float uv3[2],
const float co1[3],
const float co2[3],
const float co3[3],
const float n[3],
float r_tang[3])
{
const float s1 = uv2[0] - uv1[0];
const float s2 = uv3[0] - uv1[0];
const float t1 = uv2[1] - uv1[1];
const float t2 = uv3[1] - uv1[1];
float det = (s1 * t2 - s2 * t1);
/* otherwise 'r_tang' becomes nan */
if (det != 0.0f) {
float tangv[3], ct[3], e1[3], e2[3];
det = 1.0f / det;
/* normals in render are inversed... */
sub_v3_v3v3(e1, co1, co2);
sub_v3_v3v3(e2, co1, co3);
r_tang[0] = (t2 * e1[0] - t1 * e2[0]) * det;
r_tang[1] = (t2 * e1[1] - t1 * e2[1]) * det;
r_tang[2] = (t2 * e1[2] - t1 * e2[2]) * det;
tangv[0] = (s1 * e2[0] - s2 * e1[0]) * det;
tangv[1] = (s1 * e2[1] - s2 * e1[1]) * det;
tangv[2] = (s1 * e2[2] - s2 * e1[2]) * det;
cross_v3_v3v3(ct, r_tang, tangv);
/* check flip */
if (dot_v3v3(ct, n) < 0.0f) {
negate_v3(r_tang);
}
}
else {
zero_v3(r_tang);
}
}
/****************************** Vector Clouds ********************************/
/* vector clouds */
/**
* input
*
* \param list_size: 4 lists as pointer to array[list_size]
* \param pos: current pos array of 'new' positions
* \param weight: current weight array of 'new'weights (may be NULL pointer if you have no weights)
* \param rpos: Reference rpos array of 'old' positions
* \param rweight: Reference rweight array of 'old'weights
* (may be NULL pointer if you have no weights).
*
* output
*
* \param lloc: Center of mass pos.
* \param rloc: Center of mass rpos.
* \param lrot: Rotation matrix.
* \param lscale: Scale matrix.
*
* pointers may be NULL if not needed
*/
void vcloud_estimate_transform_v3(const int list_size,
const float (*pos)[3],
const float *weight,
const float (*rpos)[3],
const float *rweight,
float lloc[3],
float rloc[3],
float lrot[3][3],
float lscale[3][3])
{
float accu_com[3] = {0.0f, 0.0f, 0.0f}, accu_rcom[3] = {0.0f, 0.0f, 0.0f};
float accu_weight = 0.0f, accu_rweight = 0.0f;
const float eps = 1e-6f;
int a;
/* first set up a nice default response */
if (lloc) {
zero_v3(lloc);
}
if (rloc) {
zero_v3(rloc);
}
if (lrot) {
unit_m3(lrot);
}
if (lscale) {
unit_m3(lscale);
}
/* do com for both clouds */
if (pos && rpos && (list_size > 0)) { /* paranoia check */
/* do com for both clouds */
for (a = 0; a < list_size; a++) {
if (weight) {
float v[3];
copy_v3_v3(v, pos[a]);
mul_v3_fl(v, weight[a]);
add_v3_v3(accu_com, v);
accu_weight += weight[a];
}
else {
add_v3_v3(accu_com, pos[a]);
}
if (rweight) {
float v[3];
copy_v3_v3(v, rpos[a]);
mul_v3_fl(v, rweight[a]);
add_v3_v3(accu_rcom, v);
accu_rweight += rweight[a];
}
else {
add_v3_v3(accu_rcom, rpos[a]);
}
}
if (!weight || !rweight) {
accu_weight = accu_rweight = (float)list_size;
}
mul_v3_fl(accu_com, 1.0f / accu_weight);
mul_v3_fl(accu_rcom, 1.0f / accu_rweight);
if (lloc) {
copy_v3_v3(lloc, accu_com);
}
if (rloc) {
copy_v3_v3(rloc, accu_rcom);
}
if (lrot || lscale) { /* caller does not want rot nor scale, strange but legal */
/* so now do some reverse engineering and see if we can
* split rotation from scale -> Polar-decompose. */
/* build 'projection' matrix */
float m[3][3], mr[3][3], q[3][3], qi[3][3];
float va[3], vb[3], stunt[3];
float odet, ndet;
int i = 0, imax = 15;
zero_m3(m);
zero_m3(mr);
/* build 'projection' matrix */
for (a = 0; a < list_size; a++) {
sub_v3_v3v3(va, rpos[a], accu_rcom);
/* mul_v3_fl(va, bp->mass); mass needs re-normalization here ?? */
sub_v3_v3v3(vb, pos[a], accu_com);
/* mul_v3_fl(va, rp->mass); */
m[0][0] += va[0] * vb[0];
m[0][1] += va[0] * vb[1];
m[0][2] += va[0] * vb[2];
m[1][0] += va[1] * vb[0];
m[1][1] += va[1] * vb[1];
m[1][2] += va[1] * vb[2];
m[2][0] += va[2] * vb[0];
m[2][1] += va[2] * vb[1];
m[2][2] += va[2] * vb[2];
/* building the reference matrix on the fly
* needed to scale properly later */
mr[0][0] += va[0] * va[0];
mr[0][1] += va[0] * va[1];
mr[0][2] += va[0] * va[2];
mr[1][0] += va[1] * va[0];
mr[1][1] += va[1] * va[1];
mr[1][2] += va[1] * va[2];
mr[2][0] += va[2] * va[0];
mr[2][1] += va[2] * va[1];
mr[2][2] += va[2] * va[2];
}
copy_m3_m3(q, m);
stunt[0] = q[0][0];
stunt[1] = q[1][1];
stunt[2] = q[2][2];
/* Re-normalizing for numeric stability. */
mul_m3_fl(q, 1.0f / len_v3(stunt));
/* This is pretty much Polar-decompose 'inline' the algorithm based on Higham's thesis
* without the far case ... but seems to work here pretty neat. */
odet = 0.0f;
ndet = determinant_m3_array(q);
while ((odet - ndet) * (odet - ndet) > eps && i < imax) {
invert_m3_m3(qi, q);
transpose_m3(qi);
add_m3_m3m3(q, q, qi);
mul_m3_fl(q, 0.5f);
odet = ndet;
ndet = determinant_m3_array(q);
i++;
}
if (i) {
float scale[3][3];
float irot[3][3];
if (lrot) {
copy_m3_m3(lrot, q);
}
invert_m3_m3(irot, q);
invert_m3_m3(qi, mr);
mul_m3_m3m3(q, m, qi);
mul_m3_m3m3(scale, irot, q);
if (lscale) {
copy_m3_m3(lscale, scale);
}
}
}
}
}
/******************************* Form Factor *********************************/
static void vec_add_dir(float r[3], const float v1[3], const float v2[3], const float fac)
{
r[0] = v1[0] + fac * (v2[0] - v1[0]);
r[1] = v1[1] + fac * (v2[1] - v1[1]);
r[2] = v1[2] + fac * (v2[2] - v1[2]);
}
bool form_factor_visible_quad(const float p[3],
const float n[3],
const float v0[3],
const float v1[3],
const float v2[3],
float q0[3],
float q1[3],
float q2[3],
float q3[3])
{
static const float epsilon = 1e-6f;
float sd[3];
const float c = dot_v3v3(n, p);
/* signed distances from the vertices to the plane. */
sd[0] = dot_v3v3(n, v0) - c;
sd[1] = dot_v3v3(n, v1) - c;
sd[2] = dot_v3v3(n, v2) - c;
if (fabsf(sd[0]) < epsilon) {
sd[0] = 0.0f;
}
if (fabsf(sd[1]) < epsilon) {
sd[1] = 0.0f;
}
if (fabsf(sd[2]) < epsilon) {
sd[2] = 0.0f;
}
if (sd[0] > 0.0f) {
if (sd[1] > 0.0f) {
if (sd[2] > 0.0f) {
/* +++ */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
else if (sd[2] < 0.0f) {
/* ++- */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
vec_add_dir(q2, v1, v2, (sd[1] / (sd[1] - sd[2])));
vec_add_dir(q3, v0, v2, (sd[0] / (sd[0] - sd[2])));
}
else {
/* ++0 */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
}
else if (sd[1] < 0.0f) {
if (sd[2] > 0.0f) {
/* +-+ */
copy_v3_v3(q0, v0);
vec_add_dir(q1, v0, v1, (sd[0] / (sd[0] - sd[1])));
vec_add_dir(q2, v1, v2, (sd[1] / (sd[1] - sd[2])));
copy_v3_v3(q3, v2);
}
else if (sd[2] < 0.0f) {
/* +-- */
copy_v3_v3(q0, v0);
vec_add_dir(q1, v0, v1, (sd[0] / (sd[0] - sd[1])));
vec_add_dir(q2, v0, v2, (sd[0] / (sd[0] - sd[2])));
copy_v3_v3(q3, q2);
}
else {
/* +-0 */
copy_v3_v3(q0, v0);
vec_add_dir(q1, v0, v1, (sd[0] / (sd[0] - sd[1])));
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
}
else {
if (sd[2] > 0.0f) {
/* +0+ */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
else if (sd[2] < 0.0f) {
/* +0- */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
vec_add_dir(q2, v0, v2, (sd[0] / (sd[0] - sd[2])));
copy_v3_v3(q3, q2);
}
else {
/* +00 */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
}
}
else if (sd[0] < 0.0f) {
if (sd[1] > 0.0f) {
if (sd[2] > 0.0f) {
/* -++ */
vec_add_dir(q0, v0, v1, (sd[0] / (sd[0] - sd[1])));
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
vec_add_dir(q3, v0, v2, (sd[0] / (sd[0] - sd[2])));
}
else if (sd[2] < 0.0f) {
/* -+- */
vec_add_dir(q0, v0, v1, (sd[0] / (sd[0] - sd[1])));
copy_v3_v3(q1, v1);
vec_add_dir(q2, v1, v2, (sd[1] / (sd[1] - sd[2])));
copy_v3_v3(q3, q2);
}
else {
/* -+0 */
vec_add_dir(q0, v0, v1, (sd[0] / (sd[0] - sd[1])));
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
}
else if (sd[1] < 0.0f) {
if (sd[2] > 0.0f) {
/* --+ */
vec_add_dir(q0, v0, v2, (sd[0] / (sd[0] - sd[2])));
vec_add_dir(q1, v1, v2, (sd[1] / (sd[1] - sd[2])));
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
else if (sd[2] < 0.0f) {
/* --- */
return false;
}
else {
/* --0 */
return false;
}
}
else {
if (sd[2] > 0.0f) {
/* -0+ */
vec_add_dir(q0, v0, v2, (sd[0] / (sd[0] - sd[2])));
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
else if (sd[2] < 0.0f) {
/* -0- */
return false;
}
else {
/* -00 */
return false;
}
}
}
else {
if (sd[1] > 0.0f) {
if (sd[2] > 0.0f) {
/* 0++ */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
else if (sd[2] < 0.0f) {
/* 0+- */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
vec_add_dir(q2, v1, v2, (sd[1] / (sd[1] - sd[2])));
copy_v3_v3(q3, q2);
}
else {
/* 0+0 */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
}
else if (sd[1] < 0.0f) {
if (sd[2] > 0.0f) {
/* 0-+ */
copy_v3_v3(q0, v0);
vec_add_dir(q1, v1, v2, (sd[1] / (sd[1] - sd[2])));
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
else if (sd[2] < 0.0f) {
/* 0-- */
return false;
}
else {
/* 0-0 */
return false;
}
}
else {
if (sd[2] > 0.0f) {
/* 00+ */
copy_v3_v3(q0, v0);
copy_v3_v3(q1, v1);
copy_v3_v3(q2, v2);
copy_v3_v3(q3, q2);
}
else if (sd[2] < 0.0f) {
/* 00- */
return false;
}
else {
/* 000 */
return false;
}
}
}
return true;
}
/* `AltiVec` optimization, this works, but is unused. */
#if 0
# include
typedef union {
vFloat v;
float f[4];
} vFloatResult;
static vFloat vec_splat_float(float val)
{
return (vFloat){val, val, val, val};
}
static float ff_quad_form_factor(float *p, float *n, float *q0, float *q1, float *q2, float *q3)
{
vFloat vcos, rlen, vrx, vry, vrz, vsrx, vsry, vsrz, gx, gy, gz, vangle;
vUInt8 rotate = (vUInt8){4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3};
vFloatResult vresult;
float result;
/* compute r* */
vrx = (vFloat){q0[0], q1[0], q2[0], q3[0]} - vec_splat_float(p[0]);
vry = (vFloat){q0[1], q1[1], q2[1], q3[1]} - vec_splat_float(p[1]);
vrz = (vFloat){q0[2], q1[2], q2[2], q3[2]} - vec_splat_float(p[2]);
/* normalize r* */
rlen = vec_rsqrte(vrx * vrx + vry * vry + vrz * vrz + vec_splat_float(1e-16f));
vrx = vrx * rlen;
vry = vry * rlen;
vrz = vrz * rlen;
/* rotate r* for cross and dot */
vsrx = vec_perm(vrx, vrx, rotate);
vsry = vec_perm(vry, vry, rotate);
vsrz = vec_perm(vrz, vrz, rotate);
/* cross product */
gx = vsry * vrz - vsrz * vry;
gy = vsrz * vrx - vsrx * vrz;
gz = vsrx * vry - vsry * vrx;
/* normalize */
rlen = vec_rsqrte(gx * gx + gy * gy + gz * gz + vec_splat_float(1e-16f));
gx = gx * rlen;
gy = gy * rlen;
gz = gz * rlen;
/* angle */
vcos = vrx * vsrx + vry * vsry + vrz * vsrz;
vcos = vec_max(vec_min(vcos, vec_splat_float(1.0f)), vec_splat_float(-1.0f));
vangle = vacosf(vcos);
/* dot */
vresult.v = (vec_splat_float(n[0]) * gx + vec_splat_float(n[1]) * gy +
vec_splat_float(n[2]) * gz) *
vangle;
result = (vresult.f[0] + vresult.f[1] + vresult.f[2] + vresult.f[3]) * (0.5f / (float)M_PI);
result = MAX2(result, 0.0f);
return result;
}
#endif
/* SSE optimization, acos code doesn't work */
#if 0
# include "BLI_simd.h"
static __m128 sse_approx_acos(__m128 x)
{
/* needs a better approximation than Taylor expansion of acos, since that
* gives big errors for near 1.0 values, sqrt(2 * x) * acos(1 - x) should work
* better, see http://www.tom.womack.net/projects/sse-fast-arctrig.html */
return _mm_set_ps1(1.0f);
}
static float ff_quad_form_factor(float *p, float *n, float *q0, float *q1, float *q2, float *q3)
{
float r0[3], r1[3], r2[3], r3[3], g0[3], g1[3], g2[3], g3[3];
float a1, a2, a3, a4, dot1, dot2, dot3, dot4, result;
float fresult[4] __attribute__((aligned(16)));
__m128 qx, qy, qz, rx, ry, rz, rlen, srx, sry, srz, gx, gy, gz, glen, rcos, angle, aresult;
/* compute r */
qx = _mm_set_ps(q3[0], q2[0], q1[0], q0[0]);
qy = _mm_set_ps(q3[1], q2[1], q1[1], q0[1]);
qz = _mm_set_ps(q3[2], q2[2], q1[2], q0[2]);
rx = qx - _mm_set_ps1(p[0]);
ry = qy - _mm_set_ps1(p[1]);
rz = qz - _mm_set_ps1(p[2]);
/* normalize r */
rlen = _mm_rsqrt_ps(rx * rx + ry * ry + rz * rz + _mm_set_ps1(1e-16f));
rx = rx * rlen;
ry = ry * rlen;
rz = rz * rlen;
/* cross product */
srx = _mm_shuffle_ps(rx, rx, _MM_SHUFFLE(0, 3, 2, 1));
sry = _mm_shuffle_ps(ry, ry, _MM_SHUFFLE(0, 3, 2, 1));
srz = _mm_shuffle_ps(rz, rz, _MM_SHUFFLE(0, 3, 2, 1));
gx = sry * rz - srz * ry;
gy = srz * rx - srx * rz;
gz = srx * ry - sry * rx;
/* normalize g */
glen = _mm_rsqrt_ps(gx * gx + gy * gy + gz * gz + _mm_set_ps1(1e-16f));
gx = gx * glen;
gy = gy * glen;
gz = gz * glen;
/* compute angle */
rcos = rx * srx + ry * sry + rz * srz;
rcos = _mm_max_ps(_mm_min_ps(rcos, _mm_set_ps1(1.0f)), _mm_set_ps1(-1.0f));
angle = sse_approx_cos(rcos);
aresult = (_mm_set_ps1(n[0]) * gx + _mm_set_ps1(n[1]) * gy + _mm_set_ps1(n[2]) * gz) * angle;
/* sum together */
result = (fresult[0] + fresult[1] + fresult[2] + fresult[3]) * (0.5f / (float)M_PI);
result = MAX2(result, 0.0f);
return result;
}
#endif
static void ff_normalize(float n[3])
{
float d;
d = dot_v3v3(n, n);
if (d > 1.0e-35f) {
d = 1.0f / sqrtf(d);
n[0] *= d;
n[1] *= d;
n[2] *= d;
}
}
float form_factor_quad(const float p[3],
const float n[3],
const float q0[3],
const float q1[3],
const float q2[3],
const float q3[3])
{
float r0[3], r1[3], r2[3], r3[3], g0[3], g1[3], g2[3], g3[3];
float a1, a2, a3, a4, dot1, dot2, dot3, dot4, result;
sub_v3_v3v3(r0, q0, p);
sub_v3_v3v3(r1, q1, p);
sub_v3_v3v3(r2, q2, p);
sub_v3_v3v3(r3, q3, p);
ff_normalize(r0);
ff_normalize(r1);
ff_normalize(r2);
ff_normalize(r3);
cross_v3_v3v3(g0, r1, r0);
ff_normalize(g0);
cross_v3_v3v3(g1, r2, r1);
ff_normalize(g1);
cross_v3_v3v3(g2, r3, r2);
ff_normalize(g2);
cross_v3_v3v3(g3, r0, r3);
ff_normalize(g3);
a1 = saacosf(dot_v3v3(r0, r1));
a2 = saacosf(dot_v3v3(r1, r2));
a3 = saacosf(dot_v3v3(r2, r3));
a4 = saacosf(dot_v3v3(r3, r0));
dot1 = dot_v3v3(n, g0);
dot2 = dot_v3v3(n, g1);
dot3 = dot_v3v3(n, g2);
dot4 = dot_v3v3(n, g3);
result = (a1 * dot1 + a2 * dot2 + a3 * dot3 + a4 * dot4) * 0.5f / (float)M_PI;
result = MAX2(result, 0.0f);
return result;
}
float form_factor_hemi_poly(
float p[3], float n[3], float v1[3], float v2[3], float v3[3], float v4[3])
{
/* computes how much hemisphere defined by point and normal is
* covered by a quad or triangle, cosine weighted */
float q0[3], q1[3], q2[3], q3[3], contrib = 0.0f;
if (form_factor_visible_quad(p, n, v1, v2, v3, q0, q1, q2, q3)) {
contrib += form_factor_quad(p, n, q0, q1, q2, q3);
}
if (v4 && form_factor_visible_quad(p, n, v1, v3, v4, q0, q1, q2, q3)) {
contrib += form_factor_quad(p, n, q0, q1, q2, q3);
}
return contrib;
}
/**
* Check if the edge is convex or concave
* (depends on face winding)
* Copied from BM_edge_is_convex().
*/
bool is_edge_convex_v3(const float v1[3],
const float v2[3],
const float f1_no[3],
const float f2_no[3])
{
if (!equals_v3v3(f1_no, f2_no)) {
float cross[3];
float l_dir[3];
cross_v3_v3v3(cross, f1_no, f2_no);
/* we assume contiguous normals, otherwise the result isn't meaningful */
sub_v3_v3v3(l_dir, v2, v1);
return (dot_v3v3(l_dir, cross) > 0.0f);
}
return false;
}
/**
* Evaluate if entire quad is a proper convex quad
*/
bool is_quad_convex_v3(const float v1[3], const float v2[3], const float v3[3], const float v4[3])
{
/**
* Method projects points onto a plane and checks its convex using following method:
*
* - Create a plane from the cross-product of both diagonal vectors.
* - Project all points onto the plane.
* - Subtract for direction vectors.
* - Return true if all corners cross-products point the direction of the plane.
*/
/* non-unit length normal, used as a projection plane */
float plane[3];
{
float v13[3], v24[3];
sub_v3_v3v3(v13, v1, v3);
sub_v3_v3v3(v24, v2, v4);
cross_v3_v3v3(plane, v13, v24);
if (len_squared_v3(plane) < FLT_EPSILON) {
return false;
}
}
const float *quad_coords[4] = {v1, v2, v3, v4};
float quad_proj[4][3];
for (int i = 0; i < 4; i++) {
project_plane_v3_v3v3(quad_proj[i], quad_coords[i], plane);
}
float quad_dirs[4][3];
for (int i = 0, j = 3; i < 4; j = i++) {
sub_v3_v3v3(quad_dirs[i], quad_proj[i], quad_proj[j]);
}
float test_dir[3];
#define CROSS_SIGN(dir_a, dir_b) \
((void)cross_v3_v3v3(test_dir, dir_a, dir_b), (dot_v3v3(plane, test_dir) > 0.0f))
return (CROSS_SIGN(quad_dirs[0], quad_dirs[1]) && CROSS_SIGN(quad_dirs[1], quad_dirs[2]) &&
CROSS_SIGN(quad_dirs[2], quad_dirs[3]) && CROSS_SIGN(quad_dirs[3], quad_dirs[0]));
#undef CROSS_SIGN
}
bool is_quad_convex_v2(const float v1[2], const float v2[2], const float v3[2], const float v4[2])
{
/* Line-tests, the 2 diagonals have to intersect to be convex. */
return (isect_seg_seg_v2(v1, v3, v2, v4) > 0);
}
bool is_poly_convex_v2(const float verts[][2], unsigned int nr)
{
unsigned int sign_flag = 0;
unsigned int a;
const float *co_curr, *co_prev;
float dir_curr[2], dir_prev[2];
co_prev = verts[nr - 1];
co_curr = verts[0];
sub_v2_v2v2(dir_prev, verts[nr - 2], co_prev);
for (a = 0; a < nr; a++) {
float cross;
sub_v2_v2v2(dir_curr, co_prev, co_curr);
cross = cross_v2v2(dir_prev, dir_curr);
if (cross < 0.0f) {
sign_flag |= 1;
}
else if (cross > 0.0f) {
sign_flag |= 2;
}
if (sign_flag == (1 | 2)) {
return false;
}
copy_v2_v2(dir_prev, dir_curr);
co_prev = co_curr;
co_curr += 2;
}
return true;
}
/**
* Check if either of the diagonals along this quad create flipped triangles
* (normals pointing away from eachother).
* - (1 << 0): (v1-v3) is flipped.
* - (1 << 1): (v2-v4) is flipped.
*/
int is_quad_flip_v3(const float v1[3], const float v2[3], const float v3[3], const float v4[3])
{
float d_12[3], d_23[3], d_34[3], d_41[3];
float cross_a[3], cross_b[3];
int ret = 0;
sub_v3_v3v3(d_12, v1, v2);
sub_v3_v3v3(d_23, v2, v3);
sub_v3_v3v3(d_34, v3, v4);
sub_v3_v3v3(d_41, v4, v1);
cross_v3_v3v3(cross_a, d_12, d_23);
cross_v3_v3v3(cross_b, d_34, d_41);
ret |= ((dot_v3v3(cross_a, cross_b) < 0.0f) << 0);
cross_v3_v3v3(cross_a, d_23, d_34);
cross_v3_v3v3(cross_b, d_41, d_12);
ret |= ((dot_v3v3(cross_a, cross_b) < 0.0f) << 1);
return ret;
}
bool is_quad_flip_v3_first_third_fast(const float v1[3],
const float v2[3],
const float v3[3],
const float v4[3])
{
float d_12[3], d_13[3], d_14[3];
float cross_a[3], cross_b[3];
sub_v3_v3v3(d_12, v2, v1);
sub_v3_v3v3(d_13, v3, v1);
sub_v3_v3v3(d_14, v4, v1);
cross_v3_v3v3(cross_a, d_12, d_13);
cross_v3_v3v3(cross_b, d_14, d_13);
return dot_v3v3(cross_a, cross_b) > 0.0f;
}
/**
* Return the value which the distance between points will need to be scaled by,
* to define a handle, given both points are on a perfect circle.
*
* Use when we want a bezier curve to match a circle as closely as possible.
*
* \note the return value will need to be divided by 0.75 for correct results.
*/
float cubic_tangent_factor_circle_v3(const float tan_l[3], const float tan_r[3])
{
BLI_ASSERT_UNIT_V3(tan_l);
BLI_ASSERT_UNIT_V3(tan_r);
/* -7f causes instability/glitches with Bendy Bones + Custom Refs */
const float eps = 1e-5f;
const float tan_dot = dot_v3v3(tan_l, tan_r);
if (tan_dot > 1.0f - eps) {
/* no angle difference (use fallback, length wont make any difference) */
return (1.0f / 3.0f) * 0.75f;
}
if (tan_dot < -1.0f + eps) {
/* Parallel tangents (half-circle). */
return (1.0f / 2.0f);
}
/* non-aligned tangents, calculate handle length */
const float angle = acosf(tan_dot) / 2.0f;
/* could also use 'angle_sin = len_vnvn(tan_l, tan_r, dims) / 2.0' */
const float angle_sin = sinf(angle);
const float angle_cos = cosf(angle);
return ((1.0f - angle_cos) / (angle_sin * 2.0f)) / angle_sin;
}
/**
* Utility for computing approximate geodesic distances on triangle meshes.
*
* Given triangle with vertex coordinates v0, v1, v2, and known geodesic distances
* dist1 and dist2 at v1 and v2, estimate a geodesic distance at vertex v0.
*
* From "Dart Throwing on Surfaces", EGSR 2009. Section 7, Geodesic Dart Throwing.
*/
float geodesic_distance_propagate_across_triangle(
const float v0[3], const float v1[3], const float v2[3], const float dist1, const float dist2)
{
/* Vectors along triangle edges. */
float v10[3], v12[3];
sub_v3_v3v3(v10, v0, v1);
sub_v3_v3v3(v12, v2, v1);
if (dist1 != 0.0f && dist2 != 0.0f) {
/* Local coordinate system in the triangle plane. */
float u[3], v[3], n[3];
const float d12 = normalize_v3_v3(u, v12);
if (d12 * d12 > 0.0f) {
cross_v3_v3v3(n, v12, v10);
normalize_v3(n);
cross_v3_v3v3(v, n, u);
/* v0 in local coordinates */
const float v0_[2] = {dot_v3v3(v10, u), fabsf(dot_v3v3(v10, v))};
/* Compute virtual source point in local coordinates, that we estimate the geodesic
* distance is being computed from. See figure 9 in the paper for the derivation. */
const float a = 0.5f * (1.0f + (dist1 * dist1 - dist2 * dist2) / (d12 * d12));
const float hh = dist1 * dist1 - a * a * d12 * d12;
if (hh > 0.0f) {
const float h = sqrtf(hh);
const float S_[2] = {a * d12, -h};
/* Only valid if the line between the source point and v0 crosses
* the edge between v1 and v2. */
const float x_intercept = S_[0] + h * (v0_[0] - S_[0]) / (v0_[1] + h);
if (x_intercept >= 0.0f && x_intercept <= d12) {
return len_v2v2(S_, v0_);
}
}
}
}
/* Fall back to Dijsktra approximation in trivial case, or if no valid source
* point found that connects to v0 across the triangle. */
return min_ff(dist1 + len_v3(v10), dist2 + len_v3v3(v0, v2));
}