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/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* 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.
*
* Contributor(s): Joseph Eagar, Geoffrey Bantle, Campbell Barton
*
* ***** END GPL LICENSE BLOCK *****
*/
/** \file blender/bmesh/intern/bmesh_mods.c
* \ingroup bmesh
*
* This file contains functions for locally modifying
* the topology of existing mesh data. (split, join, flip etc).
*/
#include "MEM_guardedalloc.h"
#include "BLI_math.h"
#include "BLI_array.h"
#include "BLI_alloca.h"
#include "BLI_stackdefines.h"
#include "BLI_linklist_stack.h"
#include "BLI_sort_utils.h"
#include "BKE_customdata.h"
#include "bmesh.h"
#include "intern/bmesh_private.h"
// #define DEBUG_PRINT
/**
* \brief Dissolve Vert
*
* Turns the face region surrounding a manifold vertex into a single polygon.
*
* \par Example:
* <pre>
* +---------+ +---------+
* | \ / | | |
* Before: | v | After: | |
* | / \ | | |
* +---------+ +---------+
* </pre>
*
* This function can also collapse edges too
* in cases when it cant merge into faces.
*
* \par Example:
* <pre>
* Before: +----v----+ After: +---------+
* </pre>
*
* \note dissolves vert, in more situations then BM_disk_dissolve
* (e.g. if the vert is part of a wire edge, etc).
*/
bool BM_vert_dissolve(BMesh *bm, BMVert *v)
{
const int len = BM_vert_edge_count(v);
if (len == 1) {
BM_vert_kill(bm, v); /* will kill edges too */
return true;
}
else if (!BM_vert_is_manifold(v)) {
if (!v->e) {
BM_vert_kill(bm, v);
return true;
}
else if (!v->e->l) {
if (len == 2) {
return (BM_vert_collapse_edge(bm, v->e, v, true, true) != NULL);
}
else {
/* used to kill the vertex here, but it may be connected to faces.
* so better do nothing */
return false;
}
}
else {
return false;
}
}
else if (len == 2 && BM_vert_face_count(v) == 1) {
/* boundary vertex on a face */
return (BM_vert_collapse_edge(bm, v->e, v, true, true) != NULL);
}
else {
return BM_disk_dissolve(bm, v);
}
}
/**
* dissolves all faces around a vert, and removes it.
*/
bool BM_disk_dissolve(BMesh *bm, BMVert *v)
{
BMFace *f, *f2;
BMEdge *e, *keepedge = NULL, *baseedge = NULL;
int len = 0;
if (!BM_vert_is_manifold(v)) {
return false;
}
if (v->e) {
/* v->e we keep, what else */
e = v->e;
do {
e = bmesh_disk_edge_next(e, v);
if (!(BM_edge_share_face_check(e, v->e))) {
keepedge = e;
baseedge = v->e;
break;
}
len++;
} while (e != v->e);
}
/* this code for handling 2 and 3-valence verts
* may be totally bad */
if (keepedge == NULL && len == 3) {
#if 0
/* handle specific case for three-valence. solve it by
* increasing valence to four. this may be hackish. . */
BMLoop *loop = e->l;
if (loop->v == v) loop = loop->next;
if (!BM_face_split(bm, loop->f, v, loop->v, NULL, NULL, false))
return false;
if (!BM_disk_dissolve(bm, v)) {
return false;
}
#else
if (UNLIKELY(!BM_faces_join_pair(bm, e->l->f, e->l->radial_next->f, e, true))) {
return false;
}
else if (UNLIKELY(!BM_vert_collapse_faces(bm, v->e, v, 1.0, true, false, true))) {
return false;
}
#endif
return true;
}
else if (keepedge == NULL && len == 2) {
/* collapse the vertex */
e = BM_vert_collapse_faces(bm, v->e, v, 1.0, true, true, true);
if (!e) {
return false;
}
/* handle two-valence */
f = e->l->f;
f2 = e->l->radial_next->f;
if (f != f2 && !BM_faces_join_pair(bm, f, f2, e, true)) {
return false;
}
return true;
}
if (keepedge) {
bool done = false;
while (!done) {
done = true;
e = v->e;
do {
f = NULL;
if (BM_edge_is_manifold(e) && (e != baseedge) && (e != keepedge)) {
f = BM_faces_join_pair(bm, e->l->f, e->l->radial_next->f, e, true);
/* return if couldn't join faces in manifold
* conditions */
/* !disabled for testing why bad things happen */
if (!f) {
return false;
}
}
if (f) {
done = false;
break;
}
} while ((e = bmesh_disk_edge_next(e, v)) != v->e);
}
/* collapse the vertex */
/* note, the baseedge can be a boundary of manifold, use this as join_faces arg */
e = BM_vert_collapse_faces(bm, baseedge, v, 1.0, true, !BM_edge_is_boundary(baseedge), true);
if (!e) {
return false;
}
if (e->l) {
/* get remaining two faces */
f = e->l->f;
f2 = e->l->radial_next->f;
if (f != f2) {
/* join two remaining faces */
if (!BM_faces_join_pair(bm, f, f2, e, true)) {
return false;
}
}
}
}
return true;
}
/**
* \brief Faces Join Pair
*
* Joins two adjacent faces together.
*
* Because this method calls to #BM_faces_join to do its work, if a pair
* of faces share multiple edges, the pair of faces will be joined at
* every edge (not just edge \a e). This part of the functionality might need
* to be reconsidered.
*
* If the windings do not match the winding of the new face will follow
* \a f_a's winding (i.e. \a f_b will be reversed before the join).
*
* \return pointer to the combined face
*/
BMFace *BM_faces_join_pair(BMesh *bm, BMFace *f_a, BMFace *f_b, BMEdge *e, const bool do_del)
{
BMFace *faces[2] = {f_a, f_b};
BMLoop *l_a = BM_face_edge_share_loop(f_a, e);
BMLoop *l_b = BM_face_edge_share_loop(f_b, e);
BLI_assert(l_a && l_b);
if (l_a->v == l_b->v) {
bmesh_loop_reverse(bm, f_b);
}
return BM_faces_join(bm, faces, 2, do_del);
}
/**
* \brief Face Split
*
* Split a face along two vertices. returns the newly made face, and sets
* the \a r_l member to a loop in the newly created edge.
*
* \param bm The bmesh
* \param f the original face
* \param v1, v2 vertices which define the split edge, must be different
* \param r_l pointer which will receive the BMLoop for the split edge in the new face
* \param example Edge used for attributes of splitting edge, if non-NULL
* \param nodouble Use an existing edge if found
*
* \return Pointer to the newly created face representing one side of the split
* if the split is successful (and the original original face will be the
* other side). NULL if the split fails.
*/
BMFace *BM_face_split(BMesh *bm, BMFace *f,
BMLoop *l_a, BMLoop *l_b,
BMLoop **r_l, BMEdge *example,
const bool no_double)
{
const bool has_mdisp = CustomData_has_layer(&bm->ldata, CD_MDISPS);
BMFace *f_new, *f_tmp;
BLI_assert(l_a != l_b);
BLI_assert(f == l_a->f && f == l_b->f);
BLI_assert(!BM_loop_is_adjacent(l_a, l_b));
/* could be an assert */
if (UNLIKELY(BM_loop_is_adjacent(l_a, l_b)) ||
UNLIKELY((f != l_a->f || f != l_b->f)))
{
if (r_l) {
*r_l = NULL;
}
return NULL;
}
/* do we have a multires layer? */
if (has_mdisp) {
f_tmp = BM_face_copy(bm, bm, f, false, false);
}
#ifdef USE_BMESH_HOLES
f_new = bmesh_sfme(bm, f, l_a, l_b, r_l, NULL, example, no_double);
#else
f_new = bmesh_sfme(bm, f, l_a, l_b, r_l, example, no_double);
#endif
if (f_new) {
/* handle multires update */
if (has_mdisp) {
BMLoop *l_iter;
BMLoop *l_first;
l_iter = l_first = BM_FACE_FIRST_LOOP(f);
do {
BM_loop_interp_multires(bm, l_iter, f_tmp);
} while ((l_iter = l_iter->next) != l_first);
l_iter = l_first = BM_FACE_FIRST_LOOP(f_new);
do {
BM_loop_interp_multires(bm, l_iter, f_tmp);
} while ((l_iter = l_iter->next) != l_first);
#if 0
/* BM_face_multires_bounds_smooth doesn't flip displacement correct */
BM_face_multires_bounds_smooth(bm, f);
BM_face_multires_bounds_smooth(bm, f_new);
#endif
}
}
if (has_mdisp) {
BM_face_kill(bm, f_tmp);
}
return f_new;
}
/**
* \brief Face Split with intermediate points
*
* Like BM_face_split, but with an edge split by \a n intermediate points with given coordinates.
*
* \param bm The bmesh
* \param f the original face
* \param l_a, l_b vertices which define the split edge, must be different
* \param cos Array of coordinates for intermediate points
* \param n Length of \a cos (must be > 0)
* \param r_l pointer which will receive the BMLoop for the first split edge (from \a v1) in the new face
* \param example Edge used for attributes of splitting edge, if non-NULL
*
* \return Pointer to the newly created face representing one side of the split
* if the split is successful (and the original original face will be the
* other side). NULL if the split fails.
*/
BMFace *BM_face_split_n(BMesh *bm, BMFace *f,
BMLoop *l_a, BMLoop *l_b,
float cos[][3], int n,
BMLoop **r_l, BMEdge *example)
{
BMFace *f_new, *f_tmp;
BMLoop *l_dummy;
BMEdge *e, *e_new;
BMVert *v_new;
// BMVert *v_a = l_a->v; /* UNUSED */
BMVert *v_b = l_b->v;
int i, j;
BLI_assert(l_a != l_b);
BLI_assert(f == l_a->f && f == l_b->f);
BLI_assert(!((n == 0) && BM_loop_is_adjacent(l_a, l_b)));
/* could be an assert */
if (UNLIKELY((n == 0) && BM_loop_is_adjacent(l_a, l_b)) ||
UNLIKELY(l_a->f != l_b->f))
{
if (r_l) {
*r_l = NULL;
}
return NULL;
}
f_tmp = BM_face_copy(bm, bm, f, true, true);
if (!r_l)
r_l = &l_dummy;
#ifdef USE_BMESH_HOLES
f_new = bmesh_sfme(bm, f, l_a, l_b, r_l, NULL, example, false);
#else
f_new = bmesh_sfme(bm, f, l_a, l_b, r_l, example, false);
#endif
/* bmesh_sfme returns in r_l a Loop for f_new going from v_a to v_b.
* The radial_next is for f and goes from v_b to v_a */
if (f_new) {
e = (*r_l)->e;
for (i = 0; i < n; i++) {
v_new = bmesh_semv(bm, v_b, e, &e_new);
BLI_assert(v_new != NULL);
/* bmesh_semv returns in e_new the edge going from v_new to tv */
copy_v3_v3(v_new->co, cos[i]);
/* interpolate the loop data for the loops with (v == v_new), using orig face */
for (j = 0; j < 2; j++) {
BMEdge *e_iter = (j == 0) ? e : e_new;
BMLoop *l_iter = e_iter->l;
do {
if (l_iter->v == v_new) {
/* this interpolates both loop and vertex data */
BM_loop_interp_from_face(bm, l_iter, f_tmp, true, true);
}
} while ((l_iter = l_iter->radial_next) != e_iter->l);
}
e = e_new;
}
}
BM_face_verts_kill(bm, f_tmp);
return f_new;
}
/* -------------------------------------------------------------------- */
/* Face Split Edge-Net */
/** \name BM_face_split_edgenet and helper functions.
*
* \note Don't use #BM_edge_is_wire or #BM_edge_is_boundary
* since we need to take flagged faces into account.
* Also take care accessing e->l directly.
*
* \{ */
/* Note: All these flags _must_ be cleared on exit */
/* face is apart of the edge-net (including the original face we're splitting) */
#define FACE_NET _FLAG_WALK
/* edge is apart of the edge-net we're filling */
#define EDGE_NET _FLAG_WALK
/* tag verts we've visit */
#define VERT_VISIT _FLAG_WALK
struct VertOrder {
float angle;
BMVert *v;
};
static unsigned int bm_edge_flagged_radial_count(BMEdge *e)
{
unsigned int count = 0;
BMLoop *l;
if ((l = e->l)) {
do {
if (BM_ELEM_API_FLAG_TEST(l->f, FACE_NET)) {
count++;
}
} while ((l = l->radial_next) != e->l);
}
return count;
}
static BMLoop *bm_edge_flagged_radial_first(BMEdge *e)
{
BMLoop *l;
if ((l = e->l)) {
do {
if (BM_ELEM_API_FLAG_TEST(l->f, FACE_NET)) {
return l;
}
} while ((l = l->radial_next) != e->l);
}
return NULL;
}
static bool bm_face_split_edgenet_find_loop_pair(
BMVert *v_init, const float face_normal[3],
BMEdge *e_pair[2])
{
/* Always find one boundary edge (to determine winding)
* and one wire (if available), otherwise another boundary.
*/
BMIter iter;
BMEdge *e;
/* detect winding */
BMLoop *l_walk;
bool swap;
BLI_SMALLSTACK_DECLARE(edges_boundary, BMEdge *);
BLI_SMALLSTACK_DECLARE(edges_wire, BMEdge *);
int edges_boundary_len = 0;
int edges_wire_len = 0;
BM_ITER_ELEM (e, &iter, v_init, BM_EDGES_OF_VERT) {
if (BM_ELEM_API_FLAG_TEST(e, EDGE_NET)) {
const unsigned int count = bm_edge_flagged_radial_count(e);
if (count == 1) {
BLI_SMALLSTACK_PUSH(edges_boundary, e);
edges_boundary_len++;
}
else if (count == 0) {
BLI_SMALLSTACK_PUSH(edges_wire, e);
edges_wire_len++;
}
}
}
/* first edge should always be boundary */
if (edges_boundary_len == 0) {
return false;
}
e_pair[0] = BLI_SMALLSTACK_POP(edges_boundary);
/* attempt one boundary and one wire, or 2 boundary */
if (edges_wire_len == 0) {
if (edges_boundary_len >= 2) {
e_pair[1] = BLI_SMALLSTACK_POP(edges_boundary);
}
else {
/* one boundary and no wire */
return false;
}
}
else {
e_pair[1] = BLI_SMALLSTACK_POP(edges_wire);
if (edges_wire_len > 1) {
BMVert *v_prev = BM_edge_other_vert(e_pair[0], v_init);
BMVert *v_next;
float angle_best;
v_next = BM_edge_other_vert(e_pair[1], v_init);
angle_best = angle_on_axis_v3v3v3_v3(v_prev->co, v_init->co, v_next->co, face_normal);
while ((e = BLI_SMALLSTACK_POP(edges_wire))) {
float angle_test;
v_next = BM_edge_other_vert(e, v_init);
angle_test = angle_on_axis_v3v3v3_v3(v_prev->co, v_init->co, v_next->co, face_normal);
if (angle_test < angle_best) {
angle_best = angle_test;
e_pair[1] = e;
}
}
}
}
/* flip based on winding */
l_walk = bm_edge_flagged_radial_first(e_pair[0]);
swap = false;
if (face_normal == l_walk->f->no) {
swap = !swap;
}
if (l_walk->v != v_init) {
swap = !swap;
}
if (swap) {
SWAP(BMEdge *, e_pair[0], e_pair[1]);
}
return true;
}
static bool bm_face_split_edgenet_find_loop_walk(
BMVert *v_init, const float face_normal[3],
/* cache to avoid realloc every time */
struct VertOrder *edge_order, const unsigned int edge_order_len,
BMEdge *e_pair[2])
{
/* fast-path for the common case (avoid push-pop).
* Also avoids tagging as visited since we know we
* can't reach these verts some other way */
#define USE_FASTPATH_NOFORK
BMVert *v;
BMVert *v_dst;
bool found = false;
struct VertOrder *eo;
STACK_DECLARE(edge_order);
/* store visited verts so we can clear the visit flag after execution */
BLI_SMALLSTACK_DECLARE(vert_visit, BMVert *);
/* likely this will stay very small
* all verts pushed into this stack _must_ have their previous edges set! */
BLI_SMALLSTACK_DECLARE(vert_stack, BMVert *);
BLI_SMALLSTACK_DECLARE(vert_stack_next, BMVert *);
STACK_INIT(edge_order, edge_order_len);
/* start stepping */
v = BM_edge_other_vert(e_pair[0], v_init);
v->e = e_pair[0];
BLI_SMALLSTACK_PUSH(vert_stack, v);
v_dst = BM_edge_other_vert(e_pair[1], v_init);
#ifdef DEBUG_PRINT
printf("%s: vert (search) %d\n", __func__, BM_elem_index_get(v_init));
#endif
/* This loop will keep stepping over the best possible edge,
* in most cases it finds the direct route to close the face.
*
* In cases where paths can't be closed,
* alternatives are stored in the 'vert_stack'.
*/
while ((v = BLI_SMALLSTACK_POP_EX(vert_stack, vert_stack_next))) {
BMIter eiter;
BMEdge *e_next;
BLI_SMALLSTACK_PUSH(vert_visit, v);
BM_ELEM_API_FLAG_ENABLE(v, VERT_VISIT);
#ifdef USE_FASTPATH_NOFORK
walk_nofork:
#endif
BLI_assert(STACK_SIZE(edge_order) == 0);
/* check if we're done! */
if (v == v_dst) {
found = true;
goto finally;
}
BM_ITER_ELEM (e_next, &eiter, v, BM_EDGES_OF_VERT) {
if ((v->e != e_next) &&
(BM_ELEM_API_FLAG_TEST(e_next, EDGE_NET)) &&
(bm_edge_flagged_radial_count(e_next) < 2))
{
BMVert *v_next;
v_next = BM_edge_other_vert(e_next, v);
#ifdef DEBUG_PRINT
/* indent and print */
{
BMVert *_v = v;
do {
printf(" ");
} while ((_v = BM_edge_other_vert(_v->e, _v)) != v_init);
printf("vert %d -> %d (add=%d)\n",
BM_elem_index_get(v), BM_elem_index_get(v_next),
BM_ELEM_API_FLAG_TEST(v_next, VERT_VISIT) == 0);
}
#endif
if (!BM_ELEM_API_FLAG_TEST(v_next, VERT_VISIT)) {
eo = STACK_PUSH_RET_PTR(edge_order);
eo->v = v_next;
v_next->e = e_next;
}
}
}
#ifdef USE_FASTPATH_NOFORK
if (STACK_SIZE(edge_order) == 1) {
eo = STACK_POP_PTR(edge_order);
v = eo->v;
goto walk_nofork;
}
#endif
/* sort by angle if needed */
if (STACK_SIZE(edge_order) > 1) {
unsigned int j;
BMVert *v_prev = BM_edge_other_vert(v->e, v);
for (j = 0; j < STACK_SIZE(edge_order); j++) {
edge_order[j].angle = angle_signed_on_axis_v3v3v3_v3(v_prev->co, v->co, edge_order[j].v->co, face_normal);
}
qsort(edge_order, STACK_SIZE(edge_order), sizeof(struct VertOrder), BLI_sortutil_cmp_float_reverse);
}
while ((eo = STACK_POP_PTR(edge_order))) {
BLI_SMALLSTACK_PUSH(vert_stack_next, eo->v);
}
if (!BLI_SMALLSTACK_IS_EMPTY(vert_stack_next)) {
BLI_SMALLSTACK_SWAP(vert_stack, vert_stack_next);
}
}
finally:
/* clear flag for next execution */
while ((v = BLI_SMALLSTACK_POP(vert_visit))) {
BM_ELEM_API_FLAG_DISABLE(v, VERT_VISIT);
}
return found;
#undef USE_FASTPATH_NOFORK
}
static bool bm_face_split_edgenet_find_loop(
BMVert *v_init, const float face_normal[3],
/* cache to avoid realloc every time */
struct VertOrder *edge_order, const unsigned int edge_order_len,
BMVert **r_face_verts, int *r_face_verts_len)
{
BMEdge *e_pair[2];
BMVert *v;
if (!bm_face_split_edgenet_find_loop_pair(v_init, face_normal, e_pair)) {
return false;
}
BLI_assert((bm_edge_flagged_radial_count(e_pair[0]) == 1) ||
(bm_edge_flagged_radial_count(e_pair[1]) == 1));
if (bm_face_split_edgenet_find_loop_walk(v_init, face_normal, edge_order, edge_order_len, e_pair)) {
unsigned int i = 0;
r_face_verts[i++] = v_init;
v = BM_edge_other_vert(e_pair[1], v_init);
do {
r_face_verts[i++] = v;
} while ((v = BM_edge_other_vert(v->e, v)) != v_init);
*r_face_verts_len = i;
return (i > 2) ? true : false;
}
else {
return false;
}
}
/**
* Splits a face into many smaller faces defined by an edge-net.
* handle customdata and degenerate cases.
*
* - isolated holes or unsupported face configurations, will be ignored.
* - customdata calculations aren't efficient
* (need to calculate weights for each vert).
*/
bool BM_face_split_edgenet(
BMesh *bm,
BMFace *f, BMEdge **edge_net, const int edge_net_len,
BMFace ***r_face_arr, int *r_face_arr_len)
{
/* re-use for new face verts */
BMVert **face_verts;
int face_verts_len;
BMFace **face_arr = NULL;
BLI_array_declare(face_arr);
BMVert **vert_queue;
STACK_DECLARE(vert_queue);
int i;
struct VertOrder *edge_order;
const unsigned int edge_order_len = edge_net_len + 2;
BMVert *v;
BMLoop *l_iter, *l_first;
if (!edge_net_len) {
if (r_face_arr) {
*r_face_arr = NULL;
*r_face_arr_len = 0;
}
return false;
}
/* over-alloc (probably 2-4 is only used in most cases), for the biggest-fan */
edge_order = BLI_array_alloca(edge_order, edge_order_len);
/* use later */
face_verts = BLI_array_alloca(face_verts, edge_net_len + f->len);
vert_queue = BLI_array_alloca(vert_queue, edge_net_len + f->len);
STACK_INIT(vert_queue, f->len + edge_net_len);
BLI_assert(BM_ELEM_API_FLAG_TEST(f, FACE_NET) == 0);
BM_ELEM_API_FLAG_ENABLE(f, FACE_NET);
#ifdef DEBUG
for (i = 0; i < edge_net_len; i++) {
BLI_assert(BM_ELEM_API_FLAG_TEST(edge_net[i], EDGE_NET) == 0);
}
l_iter = l_first = BM_FACE_FIRST_LOOP(f);
do {
BLI_assert(BM_ELEM_API_FLAG_TEST(l_iter->e, EDGE_NET) == 0);
} while ((l_iter = l_iter->next) != l_first);
#endif
for (i = 0; i < edge_net_len; i++) {
BM_ELEM_API_FLAG_ENABLE(edge_net[i], EDGE_NET);
}
l_iter = l_first = BM_FACE_FIRST_LOOP(f);
do {
BM_ELEM_API_FLAG_ENABLE(l_iter->e, EDGE_NET);
} while ((l_iter = l_iter->next) != l_first);
/* any vert can be used to begin with */
STACK_PUSH(vert_queue, l_first->v);
while ((v = STACK_POP(vert_queue))) {
if (bm_face_split_edgenet_find_loop(v, f->no, edge_order, edge_order_len, face_verts, &face_verts_len)) {
BMFace *f_new = BM_face_create_verts(bm, face_verts, face_verts_len, f, 0, false);
for (i = 0; i < edge_net_len; i++) {
BLI_assert(BM_ELEM_API_FLAG_TEST(edge_net[i], EDGE_NET));
}
if (f_new) {
bool l_prev_is_boundary;
BLI_array_append(face_arr, f_new);
copy_v3_v3(f_new->no, f->no);
BM_ELEM_API_FLAG_ENABLE(f_new, FACE_NET);
/* add new verts to keep finding loops for
* (verts betweem boundary and manifold edges) */
l_iter = l_first = BM_FACE_FIRST_LOOP(f_new);
l_prev_is_boundary = (bm_edge_flagged_radial_count(l_iter->prev->e) == 1);
do {
bool l_iter_is_boundary = (bm_edge_flagged_radial_count(l_iter->e) == 1);
if (l_prev_is_boundary != l_iter_is_boundary) {
STACK_PUSH(vert_queue, l_iter->v);
}
l_prev_is_boundary = l_iter_is_boundary;
} while ((l_iter = l_iter->next) != l_first);
}
}
}
if (CustomData_has_math(&bm->ldata)) {
/* reuse VERT_VISIT here to tag vert's already interpolated */
BMIter iter;
BMLoop *l_other;
/* see: #BM_loop_interp_from_face for similar logic */
void **blocks = BLI_array_alloca(blocks, f->len);
float (*cos_2d)[2] = BLI_array_alloca(cos_2d, f->len);
float *w = BLI_array_alloca(w, f->len);
float axis_mat[3][3];
float co[2];
/* interior loops */
axis_dominant_v3_to_m3(axis_mat, f->no);
/* first simply copy from existing face */
i = 0;
l_iter = l_first = BM_FACE_FIRST_LOOP(f);
do {
BM_ITER_ELEM (l_other, &iter, l_iter->v, BM_LOOPS_OF_VERT) {
if (l_other->f != f) {
CustomData_bmesh_copy_data(&bm->ldata, &bm->ldata,
l_iter->head.data, &l_other->head.data);
}
}
/* tag not to interpolate */
BM_ELEM_API_FLAG_ENABLE(l_iter->v, VERT_VISIT);
mul_v2_m3v3(cos_2d[i], axis_mat, l_iter->v->co);
blocks[i] = l_iter->head.data;
} while (i++, (l_iter = l_iter->next) != l_first);
for (i = 0; i < edge_net_len; i++) {
BM_ITER_ELEM (v, &iter, edge_net[i], BM_VERTS_OF_EDGE) {
if (!BM_ELEM_API_FLAG_TEST(v, VERT_VISIT)) {
BMIter liter;
BM_ELEM_API_FLAG_ENABLE(v, VERT_VISIT);
/* interpolate this loop, then copy to the rest */
l_first = NULL;
BM_ITER_ELEM (l_iter, &liter, v, BM_LOOPS_OF_VERT) {
if (BM_ELEM_API_FLAG_TEST(l_iter->f, FACE_NET)) {
if (l_first == NULL) {
mul_v2_m3v3(co, axis_mat, v->co);
interp_weights_poly_v2(w, cos_2d, f->len, co);
CustomData_bmesh_interp(&bm->ldata, blocks, w, NULL, f->len, l_iter->head.data);
l_first = l_iter;
}
else {
CustomData_bmesh_copy_data(&bm->ldata, &bm->ldata,
l_first->head.data, &l_iter->head.data);
}
}
}
}
}
}
}
/* cleanup */
for (i = 0; i < edge_net_len; i++) {
BM_ELEM_API_FLAG_DISABLE(edge_net[i], EDGE_NET);
/* from interp only */
BM_ELEM_API_FLAG_DISABLE(edge_net[i]->v1, VERT_VISIT);
BM_ELEM_API_FLAG_DISABLE(edge_net[i]->v2, VERT_VISIT);
}
l_iter = l_first = BM_FACE_FIRST_LOOP(f);
do {
BM_ELEM_API_FLAG_DISABLE(l_iter->e, EDGE_NET);
/* from interp only */
BM_ELEM_API_FLAG_DISABLE(l_iter->v, VERT_VISIT);
} while ((l_iter = l_iter->next) != l_first);
if (BLI_array_count(face_arr)) {
bmesh_face_swap_data(f, face_arr[0]);
BM_face_kill(bm, face_arr[0]);
face_arr[0] = f;
}
else {
BM_ELEM_API_FLAG_DISABLE(f, FACE_NET);
}
for (i = 0; i < BLI_array_count(face_arr); i++) {
BM_ELEM_API_FLAG_DISABLE(face_arr[i], FACE_NET);
}
if (r_face_arr) {
*r_face_arr = face_arr;
*r_face_arr_len = BLI_array_count(face_arr);
}
else {
if (face_arr) {
MEM_freeN(face_arr);
}
}
return true;
}
#undef FACE_NET
#undef VERT_VISIT
#undef EDGE_NET
/** \} */
/**
* \brief Vert Collapse Faces
*
* Collapses vertex \a v_kill that has only two manifold edges
* onto a vertex it shares an edge with.
* \a fac defines the amount of interpolation for Custom Data.
*
* \note that this is not a general edge collapse function.
*
* \note this function is very close to #BM_vert_collapse_edge,
* both collapse a vertex and return a new edge.
* Except this takes a factor and merges custom data.
*
* \param bm The bmesh
* \param e_kill The edge to collapse
* \param v_kill The vertex to collapse into the edge
* \param fac The factor along the edge
* \param join_faces When true the faces around the vertex will be joined
* otherwise collapse the vertex by merging the 2 edges this vert touches into one.
* \param kill_degenerate_faces Removes faces with less than 3 verts after collapsing.
*
* \returns The New Edge
*/
BMEdge *BM_vert_collapse_faces(BMesh *bm, BMEdge *e_kill, BMVert *v_kill, float fac,
const bool do_del, const bool join_faces, const bool kill_degenerate_faces)
{
BMEdge *e_new = NULL;
BMVert *tv = BM_edge_other_vert(e_kill, v_kill);
BMEdge *e2;
BMVert *tv2;
/* Only intended to be called for 2-valence vertices */
BLI_assert(bmesh_disk_count(v_kill) <= 2);
/* first modify the face loop data */
if (e_kill->l) {
BMLoop *l_iter;
const float w[2] = {1.0f - fac, fac};
l_iter = e_kill->l;
do {
if (l_iter->v == tv && l_iter->next->v == v_kill) {
void *src[2];
BMLoop *tvloop = l_iter;
BMLoop *kvloop = l_iter->next;
src[0] = kvloop->head.data;
src[1] = tvloop->head.data;
CustomData_bmesh_interp(&bm->ldata, src, w, NULL, 2, kvloop->head.data);
}
} while ((l_iter = l_iter->radial_next) != e_kill->l);
}
/* now interpolate the vertex data */
BM_data_interp_from_verts(bm, v_kill, tv, v_kill, fac);
e2 = bmesh_disk_edge_next(e_kill, v_kill);
tv2 = BM_edge_other_vert(e2, v_kill);
if (join_faces) {
BMIter fiter;
BMFace **faces = NULL;
BMFace *f;
BLI_array_staticdeclare(faces, BM_DEFAULT_ITER_STACK_SIZE);
BM_ITER_ELEM (f, &fiter, v_kill, BM_FACES_OF_VERT) {
BLI_array_append(faces, f);
}
if (BLI_array_count(faces) >= 2) {
BMFace *f2 = BM_faces_join(bm, faces, BLI_array_count(faces), true);
if (f2) {
BMLoop *l_a, *l_b;
if ((l_a = BM_face_vert_share_loop(f2, tv)) &&
(l_b = BM_face_vert_share_loop(f2, tv2)))
{
BMLoop *l_new;
if (BM_face_split(bm, f2, l_a, l_b, &l_new, NULL, false)) {
e_new = l_new->e;
}
}
}
}
BLI_assert(BLI_array_count(faces) < 8);
BLI_array_free(faces);
}
else {
/* single face or no faces */
/* same as BM_vert_collapse_edge() however we already
* have vars to perform this operation so don't call. */
e_new = bmesh_jekv(bm, e_kill, v_kill, do_del, true);
/* e_new = BM_edge_exists(tv, tv2); */ /* same as return above */
if (e_new && kill_degenerate_faces) {
BMFace **bad_faces = NULL;
BLI_array_staticdeclare(bad_faces, BM_DEFAULT_ITER_STACK_SIZE);
BMIter fiter;
BMFace *f;
BMVert *verts[2] = {e_new->v1, e_new->v2};
int i;
for (i = 0; i < 2; i++) {
/* cant kill data we loop on, build a list and remove those */
BLI_array_empty(bad_faces);
BM_ITER_ELEM (f, &fiter, verts[i], BM_FACES_OF_VERT) {
if (UNLIKELY(f->len < 3)) {
BLI_array_append(bad_faces, f);
}
}
while ((f = BLI_array_pop(bad_faces))) {
BM_face_kill(bm, f);
}
}
BLI_array_free(bad_faces);
}
}
return e_new;
}
/**
* \brief Vert Collapse Faces
*
* Collapses a vertex onto another vertex it shares an edge with.
*
* \return The New Edge
*/
BMEdge *BM_vert_collapse_edge(BMesh *bm, BMEdge *e_kill, BMVert *v_kill,
const bool do_del, const bool kill_degenerate_faces)
{
/* nice example implementation but we want loops to have their customdata
* accounted for */
#if 0
BMEdge *e_new = NULL;
/* Collapse between 2 edges */
/* in this case we want to keep all faces and not join them,
* rather just get rid of the vertex - see bug [#28645] */
BMVert *tv = BM_edge_other_vert(e_kill, v_kill);
if (tv) {
BMEdge *e2 = bmesh_disk_edge_next(e_kill, v_kill);
if (e2) {
BMVert *tv2 = BM_edge_other_vert(e2, v_kill);
if (tv2) {
/* only action, other calls here only get the edge to return */
e_new = bmesh_jekv(bm, e_kill, v_kill, do_del);
}
}
}
return e_new;
#else
/* with these args faces are never joined, same as above
* but account for loop customdata */
return BM_vert_collapse_faces(bm, e_kill, v_kill, 1.0f, do_del, false, kill_degenerate_faces);
#endif
}
#undef DO_V_INTERP
/**
* \brief Edge Split
*
* Splits an edge. \a v should be one of the vertices in \a e and defines
* the "from" end of the splitting operation: the new vertex will be
* \a percent of the way from \a v to the other end.
* The newly created edge is attached to \a v and is returned in \a r_e.
* The original edge \a e will be the other half of the split.
*
* \return The new vert
*/
BMVert *BM_edge_split(BMesh *bm, BMEdge *e, BMVert *v, BMEdge **r_e, float percent)
{
BMVert *v_new, *v2;
BMFace **oldfaces = NULL;
BMEdge *e_dummy;
BLI_array_staticdeclare(oldfaces, 32);
const bool do_mdisp = (e->l && CustomData_has_layer(&bm->ldata, CD_MDISPS));
/* we need this for handling multi-res */
if (!r_e) {
r_e = &e_dummy;
}
/* do we have a multi-res layer? */
if (do_mdisp) {
BMLoop *l;
int i;
l = e->l;
do {
BLI_array_append(oldfaces, l->f);
l = l->radial_next;
} while (l != e->l);
/* flag existing faces so we can differentiate oldfaces from new faces */
for (i = 0; i < BLI_array_count(oldfaces); i++) {
BM_ELEM_API_FLAG_ENABLE(oldfaces[i], _FLAG_OVERLAP);
oldfaces[i] = BM_face_copy(bm, bm, oldfaces[i], true, true);
BM_ELEM_API_FLAG_DISABLE(oldfaces[i], _FLAG_OVERLAP);
}
}
v2 = BM_edge_other_vert(e, v);
v_new = bmesh_semv(bm, v, e, r_e);
BLI_assert(v_new != NULL);
sub_v3_v3v3(v_new->co, v2->co, v->co);
madd_v3_v3v3fl(v_new->co, v->co, v_new->co, percent);
if (r_e) {
(*r_e)->head.hflag = e->head.hflag;
BM_elem_attrs_copy(bm, bm, e, *r_e);
}
/* v->v_new->v2 */
BM_data_interp_face_vert_edge(bm, v2, v, v_new, e, percent);
BM_data_interp_from_verts(bm, v, v2, v_new, percent);
if (do_mdisp) {
int i, j;
/* interpolate new/changed loop data from copied old faces */
for (j = 0; j < 2; j++) {
for (i = 0; i < BLI_array_count(oldfaces); i++) {
BMEdge *e1 = j ? *r_e : e;
BMLoop *l, *l2;
l = e1->l;
if (UNLIKELY(!l)) {
BMESH_ASSERT(0);
break;
}
do {
/* check this is an old face */
if (BM_ELEM_API_FLAG_TEST(l->f, _FLAG_OVERLAP)) {
BMLoop *l2_first;
l2 = l2_first = BM_FACE_FIRST_LOOP(l->f);
do {
BM_loop_interp_multires(bm, l2, oldfaces[i]);
} while ((l2 = l2->next) != l2_first);
}
l = l->radial_next;
} while (l != e1->l);
}
}
/* destroy the old faces */
for (i = 0; i < BLI_array_count(oldfaces); i++) {
BM_face_verts_kill(bm, oldfaces[i]);
}
/* fix boundaries a bit, doesn't work too well quite yet */
#if 0
for (j = 0; j < 2; j++) {
BMEdge *e1 = j ? *r_e : e;
BMLoop *l, *l2;
l = e1->l;
if (UNLIKELY(!l)) {
BMESH_ASSERT(0);
break;
}
do {
BM_face_multires_bounds_smooth(bm, l->f);
l = l->radial_next;
} while (l != e1->l);
}
#endif
BLI_array_free(oldfaces);
}
return v_new;
}
/**
* \brief Split an edge multiple times evenly
*
* \param r_varr Optional array, verts in between (v1 -> v2)
*/
BMVert *BM_edge_split_n(BMesh *bm, BMEdge *e, int numcuts, BMVert **r_varr)
{
int i;
float percent;
BMVert *v_new = NULL;
for (i = 0; i < numcuts; i++) {
percent = 1.0f / (float)(numcuts + 1 - i);
v_new = BM_edge_split(bm, e, e->v2, NULL, percent);
if (r_varr) {
/* fill in reverse order (v1 -> v2) */
r_varr[numcuts - i - 1] = v_new;
}
}
return v_new;
}
#if 0
/**
* Checks if a face is valid in the data structure
*/
bool BM_face_validate(BMFace *face, FILE *err)
{
BMIter iter;
BLI_array_declare(verts);
BMVert **verts = NULL;
BMLoop *l;
int i, j;
bool ret = true;
if (face->len == 2) {
fprintf(err, "warning: found two-edged face. face ptr: %p\n", face);
fflush(err);
}
BLI_array_grow_items(verts, face->len);
BM_ITER_ELEM_INDEX (l, &iter, face, BM_LOOPS_OF_FACE, i) {
verts[i] = l->v;
if (l->e->v1 == l->e->v2) {
fprintf(err, "Found bmesh edge with identical verts!\n");
fprintf(err, " edge ptr: %p, vert: %p\n", l->e, l->e->v1);
fflush(err);
ret = false;
}
}
for (i = 0; i < face->len; i++) {
for (j = 0; j < face->len; j++) {
if (j == i) {
continue;
}
if (verts[i] == verts[j]) {
fprintf(err, "Found duplicate verts in bmesh face!\n");
fprintf(err, " face ptr: %p, vert: %p\n", face, verts[i]);
fflush(err);
ret = false;
}
}
}
BLI_array_free(verts);
return ret;
}
#endif
/**
* Calculate the 2 loops which _would_ make up the newly rotated Edge
* but don't actually change anything.
*
* Use this to further inspect if the loops to be connected have issues:
*
* Examples:
* - the newly formed edge already exists
* - the new face would be degenerate (zero area / concave / bow-tie)
* - may want to measure if the new edge gives improved results topology.
* over the old one, as with beauty fill.
*
* \note #BM_edge_rotate_check must have already run.
*/
void BM_edge_calc_rotate(BMEdge *e, const bool ccw,
BMLoop **r_l1, BMLoop **r_l2)
{
BMVert *v1, *v2;
BMFace *fa, *fb;
/* this should have already run */
BLI_assert(BM_edge_rotate_check(e) == true);
/* we know this will work */
BM_edge_face_pair(e, &fa, &fb);
/* so we can use ccw variable correctly,
* otherwise we could use the edges verts direct */
BM_edge_ordered_verts(e, &v1, &v2);
/* we could swap the verts _or_ the faces, swapping faces
* gives more predictable results since that way the next vert
* just stitches from face fa / fb */
if (!ccw) {
SWAP(BMFace *, fa, fb);
}
*r_l1 = BM_face_other_vert_loop(fb, v2, v1);
*r_l2 = BM_face_other_vert_loop(fa, v1, v2);
}
/**
* \brief Check if Rotate Edge is OK
*
* Quick check to see if we could rotate the edge,
* use this to avoid calling exceptions on common cases.
*/
bool BM_edge_rotate_check(BMEdge *e)
{
BMFace *fa, *fb;
if (BM_edge_face_pair(e, &fa, &fb)) {
BMLoop *la, *lb;
la = BM_face_other_vert_loop(fa, e->v2, e->v1);
lb = BM_face_other_vert_loop(fb, e->v2, e->v1);
/* check that the next vert in both faces isn't the same
* (ie - the next edge doesn't share the same faces).
* since we can't rotate usefully in this case. */
if (la->v == lb->v) {
return false;
}
/* mirror of the check above but in the opposite direction */
la = BM_face_other_vert_loop(fa, e->v1, e->v2);
lb = BM_face_other_vert_loop(fb, e->v1, e->v2);
if (la->v == lb->v) {
return false;
}
return true;
}
else {
return false;
}
}
/**
* \brief Check if Edge Rotate Gives Degenerate Faces
*
* Check 2 cases
* 1) does the newly forms edge form a flipped face (compare with previous cross product)
* 2) does the newly formed edge cause a zero area corner (or close enough to be almost zero)
*
* \param e The edge to test rotation.
* \param l1,l2 are the loops of the proposed verts to rotate too and should
* be the result of calling #BM_edge_calc_rotate
*/
bool BM_edge_rotate_check_degenerate(BMEdge *e, BMLoop *l1, BMLoop *l2)
{
/* note: for these vars 'old' just means initial edge state. */
float ed_dir_old[3]; /* edge vector */
float ed_dir_new[3]; /* edge vector */
float ed_dir_new_flip[3]; /* edge vector */
float ed_dir_v1_old[3];
float ed_dir_v2_old[3];
float ed_dir_v1_new[3];
float ed_dir_v2_new[3];
float cross_old[3];
float cross_new[3];
/* original verts - these will be in the edge 'e' */
BMVert *v1_old, *v2_old;
/* verts from the loops passed */
BMVert *v1, *v2;
/* these are the opposite verts - the verts that _would_ be used if 'ccw' was inverted*/
BMVert *v1_alt, *v2_alt;
/* this should have already run */
BLI_assert(BM_edge_rotate_check(e) == true);
BM_edge_ordered_verts(e, &v1_old, &v2_old);
v1 = l1->v;
v2 = l2->v;
/* get the next vert along */
v1_alt = BM_face_other_vert_loop(l1->f, v1_old, v1)->v;
v2_alt = BM_face_other_vert_loop(l2->f, v2_old, v2)->v;
/* normalize all so comparisons are scale independent */
BLI_assert(BM_edge_exists(v1_old, v1));
BLI_assert(BM_edge_exists(v1, v1_alt));
BLI_assert(BM_edge_exists(v2_old, v2));
BLI_assert(BM_edge_exists(v2, v2_alt));
/* old and new edge vecs */
sub_v3_v3v3(ed_dir_old, v1_old->co, v2_old->co);
sub_v3_v3v3(ed_dir_new, v1->co, v2->co);
normalize_v3(ed_dir_old);
normalize_v3(ed_dir_new);
/* old edge corner vecs */
sub_v3_v3v3(ed_dir_v1_old, v1_old->co, v1->co);
sub_v3_v3v3(ed_dir_v2_old, v2_old->co, v2->co);
normalize_v3(ed_dir_v1_old);
normalize_v3(ed_dir_v2_old);
/* old edge corner vecs */
sub_v3_v3v3(ed_dir_v1_new, v1->co, v1_alt->co);
sub_v3_v3v3(ed_dir_v2_new, v2->co, v2_alt->co);
normalize_v3(ed_dir_v1_new);
normalize_v3(ed_dir_v2_new);
/* compare */
cross_v3_v3v3(cross_old, ed_dir_old, ed_dir_v1_old);
cross_v3_v3v3(cross_new, ed_dir_new, ed_dir_v1_new);
if (dot_v3v3(cross_old, cross_new) < 0.0f) { /* does this flip? */
return false;
}
cross_v3_v3v3(cross_old, ed_dir_old, ed_dir_v2_old);
cross_v3_v3v3(cross_new, ed_dir_new, ed_dir_v2_new);
if (dot_v3v3(cross_old, cross_new) < 0.0f) { /* does this flip? */
return false;
}
negate_v3_v3(ed_dir_new_flip, ed_dir_new);
/* result is zero area corner */
if ((dot_v3v3(ed_dir_new, ed_dir_v1_new) > 0.999f) ||
(dot_v3v3(ed_dir_new_flip, ed_dir_v2_new) > 0.999f))
{
return false;
}
return true;
}
bool BM_edge_rotate_check_beauty(BMEdge *e,
BMLoop *l1, BMLoop *l2)
{
/* Stupid check for now:
* Could compare angles of surrounding edges
* before & after, but this is OK.*/
return (len_squared_v3v3(e->v1->co, e->v2->co) >
len_squared_v3v3(l1->v->co, l2->v->co));
}
/**
* \brief Rotate Edge
*
* Spins an edge topologically,
* either counter-clockwise or clockwise depending on \a ccw.
*
* \return The spun edge, NULL on error
* (e.g., if the edge isn't surrounded by exactly two faces).
*
* \note This works by dissolving the edge then re-creating it,
* so the returned edge won't have the same pointer address as the original one.
*
* \see header definition for \a check_flag enum.
*/
BMEdge *BM_edge_rotate(BMesh *bm, BMEdge *e, const bool ccw, const short check_flag)
{
BMVert *v1, *v2;
BMLoop *l1, *l2;
BMFace *f;
BMEdge *e_new = NULL;
char f_hflag_prev_1;
char f_hflag_prev_2;
if (!BM_edge_rotate_check(e)) {
return NULL;
}
BM_edge_calc_rotate(e, ccw, &l1, &l2);
/* the loops will be freed so assign verts */
v1 = l1->v;
v2 = l2->v;
/* --------------------------------------- */
/* Checking Code - make sure we can rotate */
if (check_flag & BM_EDGEROT_CHECK_BEAUTY) {
if (!BM_edge_rotate_check_beauty(e, l1, l2)) {
return NULL;
}
}
/* check before applying */
if (check_flag & BM_EDGEROT_CHECK_EXISTS) {
if (BM_edge_exists(v1, v2)) {
return NULL;
}
}
/* slowest, check last */
if (check_flag & BM_EDGEROT_CHECK_DEGENERATE) {
if (!BM_edge_rotate_check_degenerate(e, l1, l2)) {
return NULL;
}
}
/* Done Checking */
/* ------------- */
/* --------------- */
/* Rotate The Edge */
/* first create the new edge, this is so we can copy the customdata from the old one
* if splice if disabled, always add in a new edge even if theres one there. */
e_new = BM_edge_create(bm, v1, v2, e, (check_flag & BM_EDGEROT_CHECK_SPLICE) ? BM_CREATE_NO_DOUBLE : BM_CREATE_NOP);
f_hflag_prev_1 = l1->f->head.hflag;
f_hflag_prev_2 = l2->f->head.hflag;
/* don't delete the edge, manually remove the edge after so we can copy its attributes */
f = BM_faces_join_pair(bm, l1->f, l2->f, e, true);
if (f == NULL) {
return NULL;
}
/* note, this assumes joining the faces _didnt_ also remove the verts.
* the #BM_edge_rotate_check will ensure this, but its possibly corrupt state or future edits
* break this */
if ((l1 = BM_face_vert_share_loop(f, v1)) &&
(l2 = BM_face_vert_share_loop(f, v2)) &&
BM_face_split(bm, f, l1, l2, NULL, NULL, true))
{
/* we should really be able to know the faces some other way,
* rather then fetching them back from the edge, but this is predictable
* where using the return values from face split isn't. - campbell */
BMFace *fa, *fb;
if (BM_edge_face_pair(e_new, &fa, &fb)) {
fa->head.hflag = f_hflag_prev_1;
fb->head.hflag = f_hflag_prev_2;
}
}
else {
return NULL;
}
return e_new;
}
/**
* \brief Rip a single face from a vertex fan
*/
BMVert *BM_face_vert_separate(BMesh *bm, BMFace *sf, BMVert *sv)
{
return bmesh_urmv(bm, sf, sv);
}
/**
* \brief Rip a single face from a vertex fan
*
* \note same as #BM_face_vert_separate but faster (avoids a loop lookup)
*/
BMVert *BM_face_loop_separate(BMesh *bm, BMLoop *sl)
{
return bmesh_urmv_loop(bm, sl);
}
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