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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): Campbell Barton
*
* ***** END GPL LICENSE BLOCK *****
*/
/** \file blender/bmesh/intern/bmesh_decimate.c
* \ingroup bmesh
*
* BMesh decimator.
*/
#include <stddef.h>
#include "MEM_guardedalloc.h"
#include "DNA_scene_types.h"
#include "BLI_math.h"
#include "BLI_quadric.h"
#include "BLI_heap.h"
#include "BKE_customdata.h"
#include "bmesh.h"
#include "bmesh_structure.h"
#include "bmesh_decimate.h"
/* defines for testing */
#define USE_CUSTOMDATA
#define USE_TRIANGULATE
/* these checks are for rare cases that we can't avoid since they are valid meshes still */
#define USE_SAFETY_CHECKS
#define BOUNDARY_PRESERVE_WEIGHT 100.0f
typedef enum CD_UseFlag {
CD_DO_VERT,
CD_DO_EDGE,
CD_DO_LOOP
} CD_UseFlag;
/* BMesh Helper Functions
* ********************** */
/**
* \param vquadrics must be calloc'd
*/
static void bm_decim_build_quadrics(BMesh *bm, Quadric *vquadrics)
{
BMIter iter;
BMFace *f;
BMEdge *e;
BM_ITER_MESH (f, &iter, bm, BM_FACES_OF_MESH) {
BMLoop *l_first;
BMLoop *l_iter;
const float *co = BM_FACE_FIRST_LOOP(f)->v->co;
const float *no = f->no;
const float offset = -dot_v3v3(no, co);
Quadric q;
BLI_quadric_from_v3_dist(&q, no, offset);
l_iter = l_first = BM_FACE_FIRST_LOOP(f);
do {
BLI_quadric_add_qu_qu(&vquadrics[BM_elem_index_get(l_iter->v)], &q);
} while ((l_iter = l_iter->next) != l_first);
}
/* boundary edges */
BM_ITER_MESH (e, &iter, bm, BM_EDGES_OF_MESH) {
if (UNLIKELY(BM_edge_is_boundary(e))) {
float edge_vector[3];
float edge_cross[3];
sub_v3_v3v3(edge_vector, e->v2->co, e->v1->co);
f = e->l->f;
cross_v3_v3v3(edge_cross, edge_vector, f->no);
if (fabsf(normalize_v3(edge_cross)) > FLT_EPSILON) {
Quadric q;
BLI_quadric_from_v3_dist(&q, edge_cross, -dot_v3v3(edge_cross, e->v1->co));
BLI_quadric_mul(&q, BOUNDARY_PRESERVE_WEIGHT);
BLI_quadric_add_qu_qu(&vquadrics[BM_elem_index_get(e->v1)], &q);
BLI_quadric_add_qu_qu(&vquadrics[BM_elem_index_get(e->v2)], &q);
}
}
}
}
static void bm_decim_calc_target_co(BMEdge *e, float optimize_co[3],
const Quadric *vquadrics)
{
/* compute an edge contration target for edge ei
* this is computed by summing it's vertices quadrics and
* optimizing the result. */
Quadric q;
BLI_quadric_add_qu_ququ(&q,
&vquadrics[BM_elem_index_get(e->v1)],
&vquadrics[BM_elem_index_get(e->v2)]);
if (BLI_quadric_optimize(&q, optimize_co)) {
return; /* all is good */
}
else {
mid_v3_v3v3(optimize_co, e->v1->co, e->v2->co);
}
}
static void bm_decim_build_edge_cost_single(BMEdge *e,
const Quadric *vquadrics, const float *vweights,
Heap *eheap, HeapNode **eheap_table)
{
const Quadric *q1, *q2;
float optimize_co[3];
float cost;
if (eheap_table[BM_elem_index_get(e)]) {
BLI_heap_remove(eheap, eheap_table[BM_elem_index_get(e)]);
}
/* check we can collapse, some edges we better not touch */
if (BM_edge_is_boundary(e)) {
if (e->l->f->len == 3) {
/* pass */
}
else {
/* only collapse tri's */
eheap_table[BM_elem_index_get(e)] = NULL;
return;
}
}
else if (BM_edge_is_manifold(e)) {
if ((e->l->f->len == 3) && (e->l->radial_next->f->len == 3)) {
/* pass */
}
else {
/* only collapse tri's */
eheap_table[BM_elem_index_get(e)] = NULL;
return;
}
}
else {
eheap_table[BM_elem_index_get(e)] = NULL;
return;
}
if (vweights) {
if ((vweights[BM_elem_index_get(e->v1)] < FLT_EPSILON) &&
(vweights[BM_elem_index_get(e->v2)] < FLT_EPSILON))
{
/* skip collapsing this edge */
eheap_table[BM_elem_index_get(e)] = NULL;
return;
}
}
/* end sanity check */
bm_decim_calc_target_co(e, optimize_co, vquadrics);
q1 = &vquadrics[BM_elem_index_get(e->v1)];
q2 = &vquadrics[BM_elem_index_get(e->v2)];
if (vweights == NULL) {
cost = (BLI_quadric_evaluate(q1, optimize_co) +
BLI_quadric_evaluate(q2, optimize_co));
}
else {
cost = ((BLI_quadric_evaluate(q1, optimize_co) * vweights[BM_elem_index_get(e->v1)]) +
(BLI_quadric_evaluate(q2, optimize_co) * vweights[BM_elem_index_get(e->v2)]));
}
// print("COST %.12f\n");
eheap_table[BM_elem_index_get(e)] = BLI_heap_insert(eheap, cost, e);
}
static void bm_decim_build_edge_cost(BMesh *bm,
const Quadric *vquadrics, const float *vweights,
Heap *eheap, HeapNode **eheap_table)
{
BMIter iter;
BMEdge *e;
unsigned int i;
BM_ITER_MESH_INDEX (e, &iter, bm, BM_EDGES_OF_MESH, i) {
eheap_table[i] = NULL; /* keep sanity check happy */
bm_decim_build_edge_cost_single(e, vquadrics, vweights, eheap, eheap_table);
}
}
#ifdef USE_TRIANGULATE
/* Temp Triangulation
* ****************** */
/**
* To keep things simple we can only collapse edges on triangulated data
* (limitation with edge collapse and error calculation functions).
*
* But to avoid annoying users by only giving triangle results, we can
* triangulate, keeping a reference between the faces, then join after
* if the edges don't collapse, this will also allow more choices when
* collapsing edges so even has some advantage over decimating quads
* directly.
*
* \return TRUE if any faces were triangulated.
*/
static int bm_decim_triangulate_begin(BMesh *bm)
{
#ifdef USE_SAFETY_CHECKS
const int check_double_edges = TRUE;
#else
const int check_double_edges = FALSE;
#endif
BMIter iter;
BMFace *f;
// int has_quad; // could optimize this a little
int has_cut = FALSE;
BLI_assert((bm->elem_index_dirty & BM_VERT) == 0);
/* first clear loop index values */
BM_ITER_MESH (f, &iter, bm, BM_FACES_OF_MESH) {
BMLoop *l_iter;
BMLoop *l_first;
l_iter = l_first = BM_FACE_FIRST_LOOP(f);
do {
BM_elem_index_set(l_iter, -1);
} while ((l_iter = l_iter->next) != l_first);
// has_quad |= (f->len == 4)
}
/* adding new faces as we loop over faces
* is normally best avoided, however in this case its not so bad because any face touched twice
* will already be triangulated*/
BM_ITER_MESH (f, &iter, bm, BM_FACES_OF_MESH) {
if (f->len == 4) {
BMLoop *f_l[4];
BMLoop *l_a, *l_b;
{
BMLoop *l_iter = BM_FACE_FIRST_LOOP(f);
f_l[0] = l_iter; l_iter = l_iter->next;
f_l[1] = l_iter; l_iter = l_iter->next;
f_l[2] = l_iter; l_iter = l_iter->next;
f_l[3] = l_iter;
}
if (len_squared_v3v3(f_l[0]->v->co, f_l[2]->v->co) <
len_squared_v3v3(f_l[1]->v->co, f_l[3]->v->co))
{
l_a = f_l[0];
l_b = f_l[2];
}
else {
l_a = f_l[1];
l_b = f_l[3];
}
{
BMFace *f_new;
BMLoop *l_new;
/* warning, NO_DOUBLE option here isn't handled as nice as it could be
* - if there is a quad that has a free standing edge joining it along
* where we want to split the face, there isnt a good way we can handle this.
* currently that edge will get removed when joining the tris back into a quad. */
f_new = BM_face_split(bm, f, l_a->v, l_b->v, &l_new, NULL, check_double_edges);
if (f_new) {
/* the value of this doesn't matter, only that the 2 loops match and have unique values */
const int f_index = BM_elem_index_get(f);
/* since we just split theres only ever 2 loops */
BLI_assert(BM_edge_is_manifold(l_new->e));
BM_elem_index_set(l_new, f_index);
BM_elem_index_set(l_new->radial_next, f_index);
BM_face_normal_update(f);
BM_face_normal_update(f_new);
has_cut = TRUE;
}
}
}
}
BLI_assert((bm->elem_index_dirty & BM_VERT) == 0);
if (has_cut) {
/* now triangulation is done we need to correct index values */
BM_mesh_elem_index_ensure(bm, BM_EDGE | BM_FACE);
}
return has_cut;
}
static void bm_decim_triangulate_end(BMesh *bm)
{
/* decimation finished, now re-join */
BMIter iter;
BMEdge *e;
/* boundary edges */
BM_ITER_MESH (e, &iter, bm, BM_EDGES_OF_MESH) {
BMLoop *l_a, *l_b;
if (BM_edge_loop_pair(e, &l_a, &l_b)) {
const int l_a_index = BM_elem_index_get(l_a);
if (l_a_index != -1) {
const int l_b_index = BM_elem_index_get(l_b);
if (l_a_index == l_b_index) {
/* highly unlikely to fail, but prevents possible double-ups */
if (l_a->f->len == 3 && l_b->f->len == 3) {
BMFace *f[2] = {l_a->f, l_b->f};
BM_faces_join(bm, f, 2, TRUE);
}
}
}
}
}
}
#endif /* USE_TRIANGULATE */
/* Edge Collapse Functions
* *********************** */
#ifdef USE_CUSTOMDATA
/**
* \param v is the target to merge into.
*/
static void bm_edge_collapse_loop_customdata(BMesh *bm, BMLoop *l, BMVert *v_clear, BMVert *v_other,
const float customdata_fac)
{
/* these don't need to be updated, since they will get removed when the edge collapses */
BMLoop *l_clear, *l_other;
const int is_manifold = BM_edge_is_manifold(l->e);
int side;
/* l defines the vert to collapse into */
/* first find the loop of 'v_other' thats attached to the face of 'l' */
if (l->v == v_clear) {
l_clear = l;
l_other = l->next;
}
else {
l_clear = l->next;
l_other = l;
}
BLI_assert(l_clear->v == v_clear);
BLI_assert(l_other->v == v_other);
/* now we have both corners of the face 'l->f' */
for (side = 0; side < 2; side++) {
int is_seam = FALSE;
void *src[2];
BMFace *f_exit = is_manifold ? l->radial_next->f : NULL;
BMEdge *e_prev = l->e;
BMLoop *l_first;
BMLoop *l_iter;
float w[2];
if (side == 0) {
l_iter = l_first = l_clear;
src[0] = l_clear->head.data;
src[1] = l_other->head.data;
w[0] = customdata_fac;
w[1] = 1.0f - customdata_fac;
}
else {
l_iter = l_first = l_other;
src[0] = l_other->head.data;
src[1] = l_clear->head.data;
w[0] = 1.0f - customdata_fac;
w[1] = customdata_fac;
}
// print_v2("weights", w);
/* WATCH IT! - should NOT reference (_clear or _other) vars for this while loop */
/* walk around the fan using 'e_prev' */
while (((l_iter = BM_vert_step_fan_loop(l_iter, &e_prev)) != l_first) && (l_iter != NULL)) {
int i;
/* quit once we hit the opposite face, if we have one */
if (f_exit && UNLIKELY(f_exit == l_iter->f)) {
break;
}
/* break out unless we find a match */
is_seam = TRUE;
/* ok. we have a loop. now be smart with it! */
for (i = 0; i < bm->ldata.totlayer; i++) {
if (CustomData_layer_has_math(&bm->ldata, i)) {
const int offset = bm->ldata.layers[i].offset;
const int type = bm->ldata.layers[i].type;
void *cd_src, *cd_iter;
/* todo, make nicer macros for this */
cd_src = (char *)src[0] + offset;
// cd_dst = (char *)src[1] + offset; // UNUSED
cd_iter = (char *)l_iter->head.data + offset;
/* detect seams */
if (CustomData_data_equals(type, cd_src, cd_iter)) {
CustomData_bmesh_interp(&bm->ldata, src, w, NULL, 2, l_iter->head.data);
is_seam = FALSE;
}
}
}
if (is_seam) {
break;
}
}
}
}
#endif /* USE_CUSTOMDATA */
/**
* Check if the collapse will result in a degenerate mesh,
* that is - duplicate edges or faces.
*
* This situation could be checked for when calculating collapse cost
* however its quite slow and a degenerate collapse could eventuate
* after the cost is calculated, so instead, check just before collapsing.
*/
static void bm_edge_tag_enable(BMEdge *e)
{
BM_elem_flag_enable(e->v1, BM_ELEM_TAG);
BM_elem_flag_enable(e->v2, BM_ELEM_TAG);
if (e->l) {
BM_elem_flag_enable(e->l->f, BM_ELEM_TAG);
if (e->l != e->l->radial_next) {
BM_elem_flag_enable(e->l->radial_next->f, BM_ELEM_TAG);
}
}
}
static void bm_edge_tag_disable(BMEdge *e)
{
BM_elem_flag_disable(e->v1, BM_ELEM_TAG);
BM_elem_flag_disable(e->v2, BM_ELEM_TAG);
if (e->l) {
BM_elem_flag_disable(e->l->f, BM_ELEM_TAG);
if (e->l != e->l->radial_next) {
BM_elem_flag_disable(e->l->radial_next->f, BM_ELEM_TAG);
}
}
}
static int bm_edge_tag_test(BMEdge *e)
{
/* is the edge or one of its faces tagged? */
return (BM_elem_flag_test(e->v1, BM_ELEM_TAG) ||
BM_elem_flag_test(e->v2, BM_ELEM_TAG) ||
(e->l && (BM_elem_flag_test(e->l->f, BM_ELEM_TAG) ||
(e->l != e->l->radial_next &&
BM_elem_flag_test(e->l->radial_next->f, BM_ELEM_TAG))))
);
}
static int bm_edge_collapse_is_degenerate(BMEdge *e_first)
{
/* simply check that there is no overlap between faces and edges of each vert,
* (excluding the 2 faces attached to 'e' and 'e' its self) */
BMEdge *e_iter;
/* clear flags on both disks */
e_iter = e_first;
do {
if (!(BM_edge_is_manifold(e_iter) || BM_edge_is_boundary(e_iter))) {
return TRUE;
}
bm_edge_tag_disable(e_iter);
} while ((e_iter = bmesh_disk_edge_next(e_iter, e_first->v1)) != e_first);
e_iter = e_first;
do {
if (!(BM_edge_is_manifold(e_iter) || BM_edge_is_boundary(e_iter))) {
return TRUE;
}
bm_edge_tag_disable(e_iter);
} while ((e_iter = bmesh_disk_edge_next(e_iter, e_first->v2)) != e_first);
/* now enable one side... */
e_iter = e_first;
do {
bm_edge_tag_enable(e_iter);
} while ((e_iter = bmesh_disk_edge_next(e_iter, e_first->v1)) != e_first);
/* ... except for the edge we will collapse, we know thats shared,
* disable this to avoid false positive. We could be smart and never enable these
* face/edge tags in the first place but easier to do this */
// bm_edge_tag_disable(e_first);
/* do inline... */
{
#if 0
BMIter iter;
BMIter liter;
BMLoop *l;
BMVert *v;
BM_ITER_ELEM (l, &liter, e_first, BM_LOOPS_OF_EDGE) {
BM_elem_flag_disable(l->f, BM_ELEM_TAG);
BM_ITER_ELEM (v, &iter, l->f, BM_VERTS_OF_FACE) {
BM_elem_flag_disable(v, BM_ELEM_TAG);
}
}
#else
/* we know each face is a triangle, no looping/iterators needed here */
BMLoop *l_radial;
BMLoop *l_face;
l_radial = e_first->l;
l_face = l_radial;
BLI_assert(l_face->f->len == 3);
BM_elem_flag_disable(l_face->f, BM_ELEM_TAG);
BM_elem_flag_disable((l_face = l_radial)->v, BM_ELEM_TAG);
BM_elem_flag_disable((l_face = l_face->next)->v, BM_ELEM_TAG);
BM_elem_flag_disable(( l_face->next)->v, BM_ELEM_TAG);
l_face = l_radial->radial_next;
if (l_radial != l_face) {
BLI_assert(l_face->f->len == 3);
BM_elem_flag_disable(l_face->f, BM_ELEM_TAG);
BM_elem_flag_disable((l_face = l_radial->radial_next)->v, BM_ELEM_TAG);
BM_elem_flag_disable((l_face = l_face->next)->v, BM_ELEM_TAG);
BM_elem_flag_disable(( l_face->next)->v, BM_ELEM_TAG);
}
#endif
}
/* and check for overlap */
e_iter = e_first;
do {
if (bm_edge_tag_test(e_iter)) {
return TRUE;
}
} while ((e_iter = bmesh_disk_edge_next(e_iter, e_first->v2)) != e_first);
return FALSE;
}
/**
* special, highly limited edge collapse function
* intended for speed over flexibiliy.
* can only collapse edges connected to (1, 2) tris.
*
* Important - dont add vert/edge/face data on collapsing!
*
* \param e_clear_other let caller know what edges we remove besides \a e_clear
* \param customdata_flag merge factor, scales from 0 - 1 ('v_clear' -> 'v_other')
*/
static int bm_edge_collapse(BMesh *bm, BMEdge *e_clear, BMVert *v_clear, int r_e_clear_other[2],
#ifdef USE_CUSTOMDATA
const CD_UseFlag customdata_flag,
const float customdata_fac
#else
const CD_UseFlag UNUSED(customdata_flag),
const float UNUSED(customdata_fac)
#endif
)
{
BMVert *v_other;
/* disallow collapsing which results in degenerate cases */
if (bm_edge_collapse_is_degenerate(e_clear)) {
return FALSE;
}
v_other = BM_edge_other_vert(e_clear, v_clear);
BLI_assert(v_other != NULL);
if (BM_edge_is_manifold(e_clear)) {
BMLoop *l_a, *l_b;
BMEdge *e_a_other[2], *e_b_other[2];
int ok;
ok = BM_edge_loop_pair(e_clear, &l_a, &l_b);
BLI_assert(ok == TRUE);
BLI_assert(l_a->f->len == 3);
BLI_assert(l_b->f->len == 3);
/* keep 'v_clear' 0th */
if (BM_vert_in_edge(l_a->prev->e, v_clear)) {
e_a_other[0] = l_a->prev->e;
e_a_other[1] = l_a->next->e;
}
else {
e_a_other[1] = l_a->prev->e;
e_a_other[0] = l_a->next->e;
}
if (BM_vert_in_edge(l_b->prev->e, v_clear)) {
e_b_other[0] = l_b->prev->e;
e_b_other[1] = l_b->next->e;
}
else {
e_b_other[1] = l_b->prev->e;
e_b_other[0] = l_b->next->e;
}
BLI_assert(BM_edge_share_vert(e_a_other[0], e_b_other[0]));
BLI_assert(BM_edge_share_vert(e_a_other[1], e_b_other[1]));
/* we could assert this case, but better just bail out */
#if 0
BLI_assert(e_a_other[0] != e_b_other[0]);
BLI_assert(e_a_other[0] != e_b_other[1]);
BLI_assert(e_b_other[0] != e_a_other[0]);
BLI_assert(e_b_other[0] != e_a_other[1]);
#endif
/* not totally common but we want to avoid */
if (ELEM(e_a_other[0], e_b_other[0], e_b_other[1]) ||
ELEM(e_a_other[1], e_b_other[0], e_b_other[1]))
{
return FALSE;
}
r_e_clear_other[0] = BM_elem_index_get(e_a_other[0]);
r_e_clear_other[1] = BM_elem_index_get(e_b_other[0]);
#ifdef USE_CUSTOMDATA
/* before killing, do customdata */
if (customdata_flag & CD_DO_VERT) {
BM_data_interp_from_verts(bm, v_other, v_clear, v_other, customdata_fac);
}
if (customdata_flag & CD_DO_EDGE) {
BM_data_interp_from_edges(bm, e_a_other[1], e_a_other[0], e_a_other[1], customdata_fac);
BM_data_interp_from_edges(bm, e_b_other[1], e_b_other[0], e_b_other[1], customdata_fac);
}
if (customdata_flag & CD_DO_LOOP) {
bm_edge_collapse_loop_customdata(bm, e_clear->l, v_clear, v_other, customdata_fac);
bm_edge_collapse_loop_customdata(bm, e_clear->l->radial_next, v_clear, v_other, customdata_fac);
}
#endif
BM_edge_kill(bm, e_clear);
BM_vert_splice(bm, v_clear, v_other);
BM_edge_splice(bm, e_a_other[0], e_a_other[1]);
BM_edge_splice(bm, e_b_other[0], e_b_other[1]);
// BM_mesh_validate(bm);
return TRUE;
}
else if (BM_edge_is_boundary(e_clear)) {
/* same as above but only one triangle */
BMLoop *l_a;
BMEdge *e_a_other[2];
l_a = e_clear->l;
BLI_assert(l_a->f->len == 3);
/* keep 'v_clear' 0th */
if (BM_vert_in_edge(l_a->prev->e, v_clear)) {
e_a_other[0] = l_a->prev->e;
e_a_other[1] = l_a->next->e;
}
else {
e_a_other[1] = l_a->prev->e;
e_a_other[0] = l_a->next->e;
}
r_e_clear_other[0] = BM_elem_index_get(e_a_other[0]);
r_e_clear_other[1] = -1;
#ifdef USE_CUSTOMDATA
/* before killing, do customdata */
if (customdata_flag & CD_DO_VERT) {
BM_data_interp_from_verts(bm, v_other, v_clear, v_other, customdata_fac);
}
if (customdata_flag & CD_DO_EDGE) {
BM_data_interp_from_edges(bm, e_a_other[1], e_a_other[0], e_a_other[1], customdata_fac);
}
if (customdata_flag & CD_DO_LOOP) {
bm_edge_collapse_loop_customdata(bm, e_clear->l, v_clear, v_other, customdata_fac);
}
#endif
BM_edge_kill(bm, e_clear);
BM_vert_splice(bm, v_clear, v_other);
BM_edge_splice(bm, e_a_other[0], e_a_other[1]);
// BM_mesh_validate(bm);
return TRUE;
}
else {
return FALSE;
}
}
/* collapse e the edge, removing e->v2 */
static void bm_decim_edge_collapse(BMesh *bm, BMEdge *e,
Quadric *vquadrics, float *vweights,
Heap *eheap, HeapNode **eheap_table,
const CD_UseFlag customdata_flag)
{
int e_clear_other[2];
BMVert *v_other = e->v1;
int v_clear_index = BM_elem_index_get(e->v2); /* the vert is removed so only store the index */
float optimize_co[3];
float customdata_fac;
bm_decim_calc_target_co(e, optimize_co, vquadrics);
/* use for customdata merging */
if (LIKELY(compare_v3v3(e->v1->co, e->v2->co, FLT_EPSILON) == FALSE)) {
customdata_fac = line_point_factor_v3(optimize_co, e->v1->co, e->v2->co);
#if 0
/* simple test for stupid collapse */
if (customdata_fac < 0.0 - FLT_EPSILON || customdata_fac > 1.0f + FLT_EPSILON) {
return;
}
#endif
}
else {
/* avoid divide by zero */
customdata_fac = 0.5f;
}
if (bm_edge_collapse(bm, e, e->v2, e_clear_other, customdata_flag, customdata_fac)) {
/* update collapse info */
int i;
if (vweights) {
const int fac = CLAMPIS(customdata_fac, 0.0f, 1.0f);
vweights[BM_elem_index_get(v_other)] = (vweights[v_clear_index] * (1.0f - fac)) +
(vweights[BM_elem_index_get(v_other)] * fac);
}
e = NULL; /* paranoid safety check */
copy_v3_v3(v_other->co, optimize_co);
/* remove eheap */
for (i = 0; i < 2; i++) {
/* highly unlikely 'eheap_table[ke_other[i]]' would be NULL, but do for sanity sake */
if ((e_clear_other[i] != -1) && (eheap_table[e_clear_other[i]] != NULL)) {
BLI_heap_remove(eheap, eheap_table[e_clear_other[i]]);
eheap_table[e_clear_other[i]] = NULL;
}
}
/* update vertex quadric, add kept vertex from killed vertex */
BLI_quadric_add_qu_qu(&vquadrics[BM_elem_index_get(v_other)], &vquadrics[v_clear_index]);
/* update connected normals */
/* in fact face normals are not used for progressive updates, no need to update them */
// BM_vert_normal_update_all(v);
BM_vert_normal_update(v_other);
/* update error costs and the eheap */
if (LIKELY(v_other->e)) {
BMEdge *e_iter;
BMEdge *e_first;
e_iter = e_first = v_other->e;
do {
BLI_assert(BM_edge_find_double(e_iter) == NULL);
bm_decim_build_edge_cost_single(e_iter, vquadrics, vweights, eheap, eheap_table);
} while ((e_iter = bmesh_disk_edge_next(e_iter, v_other)) != e_first);
}
#if 0
/* optional, update edges around the vertex face fan */
{
BMIter liter;
BMLoop *l;
BM_ITER_ELEM (l, &liter, v_other, BM_LOOPS_OF_VERT) {
if (l->f->len == 3) {
BMEdge *e_outer;
if (BM_vert_in_edge(l->prev->e, l->v))
e_outer = l->next->e;
else
e_outer = l->prev->e;
BLI_assert(BM_vert_in_edge(e_outer, l->v) == FALSE);
bm_decim_build_edge_cost_single(e_outer, vquadrics, eheap, eheap_table);
}
}
}
/* end optional update */
#endif
}
}
/* Main Decimate Function
* ********************** */
/**
* \brief BM_mesh_decimate
* \param bm The mesh
* \param factor face count multiplier [0 - 1]
* \param vertex_weights Optional array of vertex aligned weights [0 - 1],
* a vertex group is the usual source for this.
*/
void BM_mesh_decimate(BMesh *bm, const float factor, float *vweights)
{
Heap *eheap; /* edge heap */
HeapNode **eheap_table; /* edge index aligned table pointing to the eheap */
Quadric *vquadrics; /* vert index aligned quadrics */
int tot_edge_orig;
int face_tot_target;
int use_triangulate;
CD_UseFlag customdata_flag = 0;
#ifdef USE_TRIANGULATE
/* temp convert quads to triangles */
use_triangulate = bm_decim_triangulate_begin(bm);
#endif
/* alloc vars */
vquadrics = MEM_callocN(sizeof(Quadric) * bm->totvert, __func__);
/* since some edges may be degenerate, we might be over allocing a little here */
eheap = BLI_heap_new_ex(bm->totedge);
eheap_table = MEM_callocN(sizeof(HeapNode *) * bm->totedge, __func__);
tot_edge_orig = bm->totedge;
/* build initial edge collapse cost data */
bm_decim_build_quadrics(bm, vquadrics);
bm_decim_build_edge_cost(bm, vquadrics, vweights, eheap, eheap_table);
face_tot_target = bm->totface * factor;
bm->elem_index_dirty |= BM_FACE | BM_EDGE | BM_VERT;
#ifdef USE_CUSTOMDATA
/* initialize customdata flag, we only need math for loops */
if (CustomData_has_interp(&bm->vdata)) customdata_flag |= CD_DO_VERT;
if (CustomData_has_interp(&bm->edata)) customdata_flag |= CD_DO_EDGE;
if (CustomData_has_math(&bm->ldata)) customdata_flag |= CD_DO_LOOP;
#endif
/* iterative edge collapse and maintain the eheap */
while ((bm->totface > face_tot_target) && (BLI_heap_is_empty(eheap) == FALSE)) {
// const float value = BLI_heap_node_value(BLI_heap_top(eheap));
BMEdge *e = BLI_heap_popmin(eheap);
BLI_assert(BM_elem_index_get(e) < tot_edge_orig); /* handy to detect corruptions elsewhere */
// printf("COST %.10f\n", value);
/* under normal conditions wont be accessed again,
* but NULL just incase so we don't use freed node */
eheap_table[BM_elem_index_get(e)] = NULL;
bm_decim_edge_collapse(bm, e, vquadrics, vweights, eheap, eheap_table, customdata_flag);
}
#ifdef USE_TRIANGULATE
/* its possible we only had triangles, skip this step in that case */
if (LIKELY(use_triangulate)) {
/* temp convert quads to triangles */
bm_decim_triangulate_end(bm);
}
#endif
/* free vars */
MEM_freeN(vquadrics);
MEM_freeN(eheap_table);
BLI_heap_free(eheap, NULL);
/* testing only */
// BM_mesh_validate(bm);
(void)tot_edge_orig; /* quiet release build warning */
}
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