Files
test/source/blender/blenkernel/intern/mesh_mapping.cc
Bastien Montagne 7aced80eec Cleanup: blenkernel: Replace 'void' MEM_[cm]allocN with templated, type-safe MEM_[cm]allocN<T>.
The main issue of 'type-less' standard C allocations is that there is no check on
allocated type possible.

This is a serious source of annoyance (and crashes) when making some
low-level structs non-trivial, as tracking down all usages of these
structs in higher-level other structs and their allocation is... really
painful.

MEM_[cm]allocN<T> templates on the other hand do check that the
given type is trivial, at build time (static assert), which makes such issue...
trivial to catch.

NOTE: New code should strive to use MEM_new (i.e. allocation and
construction) as much as possible, even for trivial PoD types.

Pull Request: https://projects.blender.org/blender/blender/pulls/136134
2025-03-20 11:25:19 +01:00

1132 lines
42 KiB
C++

/* SPDX-FileCopyrightText: 2023 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup bke
*
* Functions for accessing mesh connectivity data.
* eg: faces connected to verts, UVs connected to verts.
*/
#include <algorithm>
#include "MEM_guardedalloc.h"
#include "atomic_ops.h"
#include "BLI_array.hh"
#include "BLI_bitmap.h"
#include "BLI_buffer.h"
#include "BLI_function_ref.hh"
#include "BLI_math_geom.h"
#include "BLI_math_vector.h"
#include "BLI_task.hh"
#include "BLI_utildefines.h"
#include "BKE_customdata.hh"
#include "BKE_mesh.hh"
#include "BKE_mesh_mapping.hh"
#include "BLI_memarena.h"
#include "BLI_strict_flags.h" /* IWYU pragma: keep. Keep last. */
/* -------------------------------------------------------------------- */
/** \name Mesh Connectivity Mapping
* \{ */
UvVertMap *BKE_mesh_uv_vert_map_create(const blender::OffsetIndices<int> faces,
const bool *hide_poly,
const bool *select_poly,
const int *corner_verts,
const float (*mloopuv)[2],
uint totvert,
const float limit[2],
const bool selected,
const bool use_winding)
{
/* NOTE: N-gon version WIP, based on #BM_uv_vert_map_create. */
UvVertMap *vmap;
UvMapVert *buf;
int i, totuv, nverts;
BLI_buffer_declare_static(blender::float2, tf_uv_buf, BLI_BUFFER_NOP, 32);
totuv = 0;
/* generate UvMapVert array */
for (const int64_t a : faces.index_range()) {
if (!selected || (!(hide_poly && hide_poly[a]) && (select_poly && select_poly[a]))) {
totuv += int(faces[a].size());
}
}
if (totuv == 0) {
return nullptr;
}
vmap = MEM_callocN<UvVertMap>("UvVertMap");
buf = vmap->buf = MEM_calloc_arrayN<UvMapVert>(size_t(totuv), "UvMapVert");
vmap->vert = MEM_calloc_arrayN<UvMapVert *>(totvert, "UvMapVert*");
if (!vmap->vert || !vmap->buf) {
BKE_mesh_uv_vert_map_free(vmap);
return nullptr;
}
bool *winding = nullptr;
if (use_winding) {
winding = MEM_calloc_arrayN<bool>(size_t(faces.size()), "winding");
}
for (const int64_t a : faces.index_range()) {
const blender::IndexRange face = faces[a];
if (!selected || (!(hide_poly && hide_poly[a]) && (select_poly && select_poly[a]))) {
float(*tf_uv)[2] = nullptr;
if (use_winding) {
tf_uv = (float(*)[2])BLI_buffer_reinit_data(
&tf_uv_buf, blender::float2, size_t(face.size()));
}
nverts = int(face.size());
for (i = 0; i < nverts; i++) {
buf->loop_of_face_index = ushort(i);
buf->face_index = uint(a);
buf->separate = false;
buf->next = vmap->vert[corner_verts[face[i]]];
vmap->vert[corner_verts[face[i]]] = buf;
if (use_winding) {
copy_v2_v2(tf_uv[i], mloopuv[face[i]]);
}
buf++;
}
if (use_winding) {
winding[a] = cross_poly_v2(tf_uv, uint(nverts)) < 0;
}
}
}
/* sort individual uvs for each vert */
for (uint a = 0; a < totvert; a++) {
UvMapVert *newvlist = nullptr, *vlist = vmap->vert[a];
UvMapVert *iterv, *v, *lastv, *next;
const float *uv, *uv2;
float uvdiff[2];
while (vlist) {
v = vlist;
vlist = vlist->next;
v->next = newvlist;
newvlist = v;
uv = mloopuv[faces[v->face_index].start() + v->loop_of_face_index];
lastv = nullptr;
iterv = vlist;
while (iterv) {
next = iterv->next;
uv2 = mloopuv[faces[iterv->face_index].start() + iterv->loop_of_face_index];
sub_v2_v2v2(uvdiff, uv2, uv);
if (fabsf(uv[0] - uv2[0]) < limit[0] && fabsf(uv[1] - uv2[1]) < limit[1] &&
(!use_winding || winding[iterv->face_index] == winding[v->face_index]))
{
if (lastv) {
lastv->next = next;
}
else {
vlist = next;
}
iterv->next = newvlist;
newvlist = iterv;
}
else {
lastv = iterv;
}
iterv = next;
}
newvlist->separate = true;
}
vmap->vert[a] = newvlist;
}
if (use_winding) {
MEM_freeN(winding);
}
BLI_buffer_free(&tf_uv_buf);
return vmap;
}
UvMapVert *BKE_mesh_uv_vert_map_get_vert(UvVertMap *vmap, uint v)
{
return vmap->vert[v];
}
void BKE_mesh_uv_vert_map_free(UvVertMap *vmap)
{
if (vmap) {
if (vmap->vert) {
MEM_freeN(vmap->vert);
}
if (vmap->buf) {
MEM_freeN(vmap->buf);
}
MEM_freeN(vmap);
}
}
void BKE_mesh_vert_corner_tri_map_create(MeshElemMap **r_map,
int **r_mem,
const int totvert,
const blender::int3 *corner_tris,
const int tris_num,
const int *corner_verts,
const int /*corners_num*/)
{
MeshElemMap *map = MEM_calloc_arrayN<MeshElemMap>(size_t(totvert), __func__);
int *indices = MEM_malloc_arrayN<int>(size_t(tris_num) * 3, __func__);
int *index_step;
int i;
/* count face users */
for (i = 0; i < tris_num; i++) {
for (int j = 3; j--;) {
map[corner_verts[corner_tris[i][j]]].count++;
}
}
/* create offsets */
index_step = indices;
for (i = 0; i < totvert; i++) {
map[i].indices = index_step;
index_step += map[i].count;
/* re-count, using this as an index below */
map[i].count = 0;
}
/* assign corner_tri-edge users */
for (i = 0; i < tris_num; i++) {
for (int j = 3; j--;) {
MeshElemMap *map_ele = &map[corner_verts[corner_tris[i][j]]];
map_ele->indices[map_ele->count++] = i;
}
}
*r_map = map;
*r_mem = indices;
}
void BKE_mesh_origindex_map_create(MeshElemMap **r_map,
int **r_mem,
const int totsource,
const int *final_origindex,
const int totfinal)
{
MeshElemMap *map = MEM_calloc_arrayN<MeshElemMap>(size_t(totsource), __func__);
int *indices = MEM_malloc_arrayN<int>(size_t(totfinal), __func__);
int *index_step;
int i;
/* count face users */
for (i = 0; i < totfinal; i++) {
if (final_origindex[i] != ORIGINDEX_NONE) {
BLI_assert(final_origindex[i] < totsource);
map[final_origindex[i]].count++;
}
}
/* create offsets */
index_step = indices;
for (i = 0; i < totsource; i++) {
map[i].indices = index_step;
index_step += map[i].count;
/* re-count, using this as an index below */
map[i].count = 0;
}
/* Assign face-tessellation users. */
for (i = 0; i < totfinal; i++) {
if (final_origindex[i] != ORIGINDEX_NONE) {
MeshElemMap *map_ele = &map[final_origindex[i]];
map_ele->indices[map_ele->count++] = i;
}
}
*r_map = map;
*r_mem = indices;
}
void BKE_mesh_origindex_map_create_corner_tri(MeshElemMap **r_map,
int **r_mem,
const blender::OffsetIndices<int> faces,
const int *corner_tri_faces,
const int corner_tris_num)
{
MeshElemMap *map = MEM_calloc_arrayN<MeshElemMap>(size_t(faces.size()), __func__);
int *indices = MEM_malloc_arrayN<int>(size_t(corner_tris_num), __func__);
int *index_step;
/* create offsets */
index_step = indices;
for (const int64_t i : faces.index_range()) {
map[i].indices = index_step;
index_step += blender::bke::mesh::face_triangles_num(int(faces[i].size()));
}
/* Assign face-tessellation users. */
for (int i = 0; i < corner_tris_num; i++) {
MeshElemMap *map_ele = &map[corner_tri_faces[i]];
map_ele->indices[map_ele->count++] = i;
}
*r_map = map;
*r_mem = indices;
}
namespace blender::bke::mesh {
static Array<int> create_reverse_offsets(const Span<int> indices, const int items_num)
{
Array<int> offsets(items_num + 1, 0);
offset_indices::build_reverse_offsets(indices, offsets);
return offsets;
}
static void sort_small_groups(const OffsetIndices<int> groups,
const int grain_size,
MutableSpan<int> indices)
{
threading::parallel_for(groups.index_range(), grain_size, [&](const IndexRange range) {
for (const int64_t index : range) {
MutableSpan<int> group = indices.slice(groups[index]);
std::sort(group.begin(), group.end());
}
});
}
static Array<int> reverse_indices_in_groups(const Span<int> group_indices,
const OffsetIndices<int> offsets)
{
if (group_indices.is_empty()) {
return {};
}
BLI_assert(*std::max_element(group_indices.begin(), group_indices.end()) < offsets.size());
BLI_assert(*std::min_element(group_indices.begin(), group_indices.end()) >= 0);
/* `counts` keeps track of how many elements have been added to each group, and is incremented
* atomically by many threads in parallel. `calloc` can be measurably faster than a parallel fill
* of zero. Alternatively the offsets could be copied and incremented directly, but the cost of
* the copy is slightly higher than the cost of `calloc`. */
int *counts = MEM_calloc_arrayN<int>(size_t(offsets.size()), __func__);
BLI_SCOPED_DEFER([&]() { MEM_freeN(counts); })
Array<int> results(group_indices.size());
threading::parallel_for(group_indices.index_range(), 1024, [&](const IndexRange range) {
for (const int64_t i : range) {
const int group_index = group_indices[i];
const int index_in_group = atomic_fetch_and_add_int32(&counts[group_index], 1);
results[offsets[group_index][index_in_group]] = int(i);
}
});
sort_small_groups(offsets, 1024, results);
return results;
}
/* A version of #reverse_indices_in_groups that stores face indices instead of corner indices. */
static void reverse_group_indices_in_groups(const OffsetIndices<int> groups,
const Span<int> group_to_elem,
const OffsetIndices<int> offsets,
MutableSpan<int> results)
{
int *counts = MEM_calloc_arrayN<int>(size_t(offsets.size()), __func__);
BLI_SCOPED_DEFER([&]() { MEM_freeN(counts); })
threading::parallel_for(groups.index_range(), 1024, [&](const IndexRange range) {
for (const int64_t face : range) {
for (const int elem : group_to_elem.slice(groups[face])) {
const int index_in_group = atomic_fetch_and_add_int32(&counts[elem], 1);
results[offsets[elem][index_in_group]] = int(face);
}
}
});
sort_small_groups(offsets, 1024, results);
}
static GroupedSpan<int> gather_groups(const Span<int> group_indices,
const int groups_num,
Array<int> &r_offsets,
Array<int> &r_indices)
{
r_offsets = create_reverse_offsets(group_indices, groups_num);
r_indices = reverse_indices_in_groups(group_indices, r_offsets.as_span());
return {OffsetIndices<int>(r_offsets), r_indices};
}
Array<int> build_corner_to_face_map(const OffsetIndices<int> faces)
{
Array<int> map(faces.total_size());
offset_indices::build_reverse_map(faces, map);
return map;
}
GroupedSpan<int> build_vert_to_edge_map(const Span<int2> edges,
const int verts_num,
Array<int> &r_offsets,
Array<int> &r_indices)
{
r_offsets = create_reverse_offsets(edges.cast<int>(), verts_num);
const OffsetIndices<int> offsets(r_offsets);
r_indices.reinitialize(offsets.total_size());
/* Version of #reverse_indices_in_groups that accounts for storing two indices for each edge. */
int *counts = MEM_calloc_arrayN<int>(size_t(offsets.size()), __func__);
BLI_SCOPED_DEFER([&]() { MEM_freeN(counts); })
threading::parallel_for(edges.index_range(), 1024, [&](const IndexRange range) {
for (const int64_t edge : range) {
for (const int vert : {edges[edge][0], edges[edge][1]}) {
const int index_in_group = atomic_fetch_and_add_int32(&counts[vert], 1);
r_indices[offsets[vert][index_in_group]] = int(edge);
}
}
});
sort_small_groups(offsets, 1024, r_indices);
return {offsets, r_indices};
}
void build_vert_to_face_indices(const OffsetIndices<int> faces,
const Span<int> corner_verts,
const OffsetIndices<int> offsets,
MutableSpan<int> face_indices)
{
reverse_group_indices_in_groups(faces, corner_verts, offsets, face_indices);
}
GroupedSpan<int> build_vert_to_face_map(const OffsetIndices<int> faces,
const Span<int> corner_verts,
const int verts_num,
Array<int> &r_offsets,
Array<int> &r_indices)
{
r_offsets = create_reverse_offsets(corner_verts, verts_num);
r_indices.reinitialize(r_offsets.last());
build_vert_to_face_indices(faces, corner_verts, OffsetIndices<int>(r_offsets), r_indices);
return {OffsetIndices<int>(r_offsets), r_indices};
}
Array<int> build_vert_to_corner_indices(const Span<int> corner_verts,
const OffsetIndices<int> offsets)
{
return reverse_indices_in_groups(corner_verts, offsets);
}
GroupedSpan<int> build_vert_to_corner_map(const Span<int> corner_verts,
const int verts_num,
Array<int> &r_offsets,
Array<int> &r_indices)
{
return gather_groups(corner_verts, verts_num, r_offsets, r_indices);
}
GroupedSpan<int> build_edge_to_corner_map(const Span<int> corner_edges,
const int edges_num,
Array<int> &r_offsets,
Array<int> &r_indices)
{
return gather_groups(corner_edges, edges_num, r_offsets, r_indices);
}
GroupedSpan<int> build_edge_to_face_map(const OffsetIndices<int> faces,
const Span<int> corner_edges,
const int edges_num,
Array<int> &r_offsets,
Array<int> &r_indices)
{
r_offsets = create_reverse_offsets(corner_edges, edges_num);
r_indices.reinitialize(r_offsets.last());
reverse_group_indices_in_groups(faces, corner_edges, OffsetIndices<int>(r_offsets), r_indices);
return {OffsetIndices<int>(r_offsets), r_indices};
}
} // namespace blender::bke::mesh
/** \} */
/* -------------------------------------------------------------------- */
/** \name Mesh loops/face islands.
* Used currently for UVs and 'smooth groups'.
* \{ */
/**
* Callback deciding whether the given face/loop/edge define an island boundary or not.
*/
using MeshRemap_CheckIslandBoundary =
blender::FunctionRef<bool(int face_index,
int corner,
int edge_index,
int edge_user_count,
const blender::Span<int> edge_face_map_elem)>;
static void face_edge_loop_islands_calc_bitflags_exclude_at_boundary(
const int *face_groups,
const blender::Span<int> faces_from_item,
const int face_group_id,
const int face_group_id_overflowed,
int &r_bit_face_group_mask)
{
/* Find neighbor faces (either from a boundary edge, or a boundary vertex) that already have a
* group assigned, and exclude these groups' bits from the available set of groups bits that can
* be assigned to the currently processed group. */
for (const int face_idx : faces_from_item) {
int bit = face_groups[face_idx];
if (!ELEM(bit, 0, face_group_id, face_group_id_overflowed) && !(r_bit_face_group_mask & bit)) {
r_bit_face_group_mask |= bit;
}
}
}
/**
* ABOUT #use_boundary_vertices_for_bitflags:
*
* Also exclude bits used in other groups sharing the same boundary vertex, i.e. if one edge
* around the vertex of the current corner is a boundary edge.
*
* NOTE: The reason for this requirement is not very clear. Bit-flags groups are only handled here
* for I/O purposes, Blender itself does not have this feature. Main external apps heavily
* relying on these bit-flags groups for their smooth shading computation seem to generate invalid
* results when two different groups share the same bits, and are connected by a vertex only
* (i.e. have no edge in common). See #104434.
*
* The downside of also considering boundary vertex-only neighbor faces is that it becomes much
* more likely to run out of bits, e.g. in a case of a fan with many faces/edges around a same
* vertex, each in their own face group...
*/
static void face_edge_loop_islands_calc(const int totedge,
const int totvert,
const blender::OffsetIndices<int> faces,
const blender::Span<int> corner_edges,
const blender::Span<int> corner_verts,
blender::GroupedSpan<int> edge_face_map,
blender::GroupedSpan<int> vert_face_map,
const bool use_bitflags,
const bool use_boundary_vertices_for_bitflags,
MeshRemap_CheckIslandBoundary edge_boundary_check,
int **r_face_groups,
int *r_totgroup,
BLI_bitmap **r_edge_boundaries,
int *r_totedgeboundaries)
{
int *face_groups;
int *face_stack;
BLI_bitmap *edge_boundaries = nullptr;
int num_edgeboundaries = 0;
int face_prev = 0;
constexpr int temp_face_group_id = 3; /* Placeholder value. */
/* For bitflags groups, group we could not find any available bit for, will be reset to 0 at the
* end. */
constexpr int face_group_id_overflowed = 5;
int tot_group = 0;
bool group_id_overflow = false;
if (faces.is_empty()) {
*r_totgroup = 0;
*r_face_groups = nullptr;
if (r_edge_boundaries) {
*r_edge_boundaries = nullptr;
*r_totedgeboundaries = 0;
}
return;
}
if (r_edge_boundaries) {
edge_boundaries = BLI_BITMAP_NEW(totedge, __func__);
*r_totedgeboundaries = 0;
}
blender::Array<int> edge_to_face_src_offsets;
blender::Array<int> edge_to_face_src_indices;
if (edge_face_map.is_empty()) {
edge_face_map = blender::bke::mesh::build_edge_to_face_map(
faces, corner_edges, totedge, edge_to_face_src_offsets, edge_to_face_src_indices);
}
blender::Array<int> vert_to_face_src_offsets;
blender::Array<int> vert_to_face_src_indices;
if (use_bitflags && vert_face_map.is_empty()) {
vert_face_map = blender::bke::mesh::build_vert_to_face_map(
faces, corner_verts, totvert, vert_to_face_src_offsets, vert_to_face_src_indices);
}
face_groups = MEM_calloc_arrayN<int>(size_t(faces.size()), __func__);
face_stack = MEM_malloc_arrayN<int>(size_t(faces.size()), __func__);
while (true) {
int face;
int bit_face_group_mask = 0;
int face_group_id;
int ps_curr_idx = 0, ps_end_idx = 0; /* stack indices */
for (face = face_prev; face < int(faces.size()); face++) {
if (face_groups[face] == 0) {
break;
}
}
if (face == int(faces.size())) {
/* all done */
break;
}
face_group_id = use_bitflags ? temp_face_group_id : ++tot_group;
/* start searching from here next time */
face_prev = face + 1;
face_groups[face] = face_group_id;
face_stack[ps_end_idx++] = face;
while (ps_curr_idx != ps_end_idx) {
face = face_stack[ps_curr_idx++];
BLI_assert(face_groups[face] == face_group_id);
for (const int64_t loop : faces[face]) {
const int edge = corner_edges[loop];
/* loop over face users */
const blender::Span<int> map_ele = edge_face_map[edge];
const int *p = map_ele.data();
int i = int(map_ele.size());
if (!edge_boundary_check(face, int(loop), edge, i, map_ele)) {
for (; i--; p++) {
/* if we meet other non initialized its a bug */
BLI_assert(ELEM(face_groups[*p], 0, face_group_id));
if (face_groups[*p] == 0) {
face_groups[*p] = face_group_id;
face_stack[ps_end_idx++] = *p;
}
}
}
else {
if (edge_boundaries && !BLI_BITMAP_TEST(edge_boundaries, edge)) {
BLI_BITMAP_ENABLE(edge_boundaries, edge);
num_edgeboundaries++;
}
if (use_bitflags) {
/* Exclude bits used in other groups sharing the same boundary edge. */
face_edge_loop_islands_calc_bitflags_exclude_at_boundary(face_groups,
map_ele,
face_group_id,
face_group_id_overflowed,
bit_face_group_mask);
if (use_boundary_vertices_for_bitflags) {
/* Exclude bits used in other groups sharing the same boundary vertex. */
/* NOTE: Checking one vertex for each edge (the corner vertex) should be enough:
* - Thanks to winding, a fully boundary vertex (i.e. a vertex for which at least
* two of the adjacent edges in the same group are boundary ones) will be
* processed by at least one of the edges/corners. If not when processing the
* first face's corner, then when processing the other face's corner in the same
* group.
* - Isolated boundary edges (i.e. boundary edges only connected to faces of the
* same group) cannot be represented by bit-flags groups, at least not with
* current algorithm (they cannot define more than one group).
* - Inversions of winding (aka flipped faces) always generate boundary edges in
* current use-case (smooth groups), i.e. two faces with opposed winding cannot
* belong to the same group. */
const int vert = corner_verts[loop];
face_edge_loop_islands_calc_bitflags_exclude_at_boundary(face_groups,
vert_face_map[vert],
face_group_id,
face_group_id_overflowed,
bit_face_group_mask);
}
}
}
}
}
/* And now, we have all our face from current group in face_stack
* (from 0 to (ps_end_idx - 1)),
* as well as all smoothgroups bits we can't use in bit_face_group_mask.
*/
if (use_bitflags) {
int i, *p, gid_bit = 0;
face_group_id = 1;
/* Find first bit available! */
for (; (face_group_id & bit_face_group_mask) && (gid_bit < 32); gid_bit++) {
face_group_id <<= 1; /* will 'overflow' on last possible iteration. */
}
if (UNLIKELY(gid_bit > 31)) {
/* All bits used in contiguous smooth groups, not much to do.
*
* NOTE: If only considering boundary edges, this is *very* unlikely to happen.
* Theoretically, four groups are enough, this is probably not achievable with such a
* simple algorithm, but 32 groups should always be more than enough.
*
* When also considering boundary vertices (which is the case currently, see comment
* above), a fairly simple fan case with over 30 faces all belonging to different groups
* will be enough to cause an overflow.
*/
printf(
"Warning, could not find an available id for current smooth group, faces will me "
"marked "
"as out of any smooth group...\n");
/* Can't use 0, will have to set them to this value later. */
face_group_id = face_group_id_overflowed;
group_id_overflow = true;
}
tot_group = std::max(gid_bit, tot_group);
/* And assign the final smooth group id to that face group! */
for (i = ps_end_idx, p = face_stack; i--; p++) {
face_groups[*p] = face_group_id;
}
}
}
if (use_bitflags) {
/* used bits are zero-based. */
tot_group++;
}
if (UNLIKELY(group_id_overflow)) {
int i = int(faces.size()), *gid = face_groups;
for (; i--; gid++) {
if (*gid == face_group_id_overflowed) {
*gid = 0;
}
}
/* Using 0 as group id adds one more group! */
tot_group++;
}
MEM_freeN(face_stack);
*r_totgroup = tot_group;
*r_face_groups = face_groups;
if (r_edge_boundaries) {
*r_edge_boundaries = edge_boundaries;
*r_totedgeboundaries = num_edgeboundaries;
}
}
static int *mesh_calc_smoothgroups(const int edges_num,
const int verts_num,
const blender::OffsetIndices<int> faces,
const blender::Span<int> corner_edges,
const blender::Span<int> corner_verts,
const blender::Span<bool> sharp_edges,
const blender::Span<bool> sharp_faces,
int *r_totgroup,
const bool use_bitflags,
const bool use_boundary_vertices_for_bitflags)
{
int *face_groups = nullptr;
auto face_is_smooth = [&](const int i) { return sharp_faces.is_empty() || !sharp_faces[i]; };
auto face_is_island_boundary_smooth = [&](const int face_index,
const int /*corner*/,
const int edge_index,
const int edge_user_count,
const blender::Span<int> edge_face_map_elem) {
/* Edge is sharp if one of its faces is flat, or edge itself is sharp,
* or edge is not used by exactly two faces. */
if (face_is_smooth(face_index) && !(!sharp_edges.is_empty() && sharp_edges[edge_index]) &&
(edge_user_count == 2))
{
/* In that case, edge appears to be smooth, but we need to check its other face too. */
const int other_face_index = (face_index == edge_face_map_elem[0]) ? edge_face_map_elem[1] :
edge_face_map_elem[0];
return !face_is_smooth(other_face_index);
}
return true;
};
face_edge_loop_islands_calc(edges_num,
verts_num,
faces,
corner_edges,
corner_verts,
{},
{},
use_bitflags,
use_boundary_vertices_for_bitflags,
face_is_island_boundary_smooth,
&face_groups,
r_totgroup,
nullptr,
nullptr);
return face_groups;
}
int *BKE_mesh_calc_smoothgroups(int edges_num,
const blender::OffsetIndices<int> faces,
const blender::Span<int> corner_edges,
const blender::Span<bool> sharp_edges,
const blender::Span<bool> sharp_faces,
int *r_totgroup)
{
return mesh_calc_smoothgroups(
edges_num, 0, faces, corner_edges, {}, sharp_edges, sharp_faces, r_totgroup, false, false);
}
int *BKE_mesh_calc_smoothgroups_bitflags(int edges_num,
int verts_num,
const blender::OffsetIndices<int> faces,
const blender::Span<int> corner_edges,
const blender::Span<int> corner_verts,
const blender::Span<bool> sharp_edges,
const blender::Span<bool> sharp_faces,
const bool use_boundary_vertices_for_bitflags,
int *r_totgroup)
{
return mesh_calc_smoothgroups(edges_num,
verts_num,
faces,
corner_edges,
corner_verts,
sharp_edges,
sharp_faces,
r_totgroup,
true,
use_boundary_vertices_for_bitflags);
}
#define MISLAND_DEFAULT_BUFSIZE 64
void BKE_mesh_loop_islands_init(MeshIslandStore *island_store,
const short item_type,
const int items_num,
const short island_type,
const short innercut_type)
{
MemArena *mem = island_store->mem;
if (mem == nullptr) {
mem = BLI_memarena_new(BLI_MEMARENA_STD_BUFSIZE, __func__);
island_store->mem = mem;
}
/* else memarena should be cleared */
BLI_assert(
ELEM(item_type, MISLAND_TYPE_VERT, MISLAND_TYPE_EDGE, MISLAND_TYPE_POLY, MISLAND_TYPE_LOOP));
BLI_assert(ELEM(
island_type, MISLAND_TYPE_VERT, MISLAND_TYPE_EDGE, MISLAND_TYPE_POLY, MISLAND_TYPE_LOOP));
island_store->item_type = item_type;
island_store->items_to_islands_num = items_num;
island_store->items_to_islands = static_cast<int *>(
BLI_memarena_alloc(mem, sizeof(*island_store->items_to_islands) * size_t(items_num)));
island_store->island_type = island_type;
island_store->islands_num_alloc = MISLAND_DEFAULT_BUFSIZE;
island_store->islands = static_cast<MeshElemMap **>(
BLI_memarena_alloc(mem, sizeof(*island_store->islands) * island_store->islands_num_alloc));
island_store->innercut_type = innercut_type;
island_store->innercuts = static_cast<MeshElemMap **>(
BLI_memarena_alloc(mem, sizeof(*island_store->innercuts) * island_store->islands_num_alloc));
}
void BKE_mesh_loop_islands_clear(MeshIslandStore *island_store)
{
island_store->item_type = MISLAND_TYPE_NONE;
island_store->items_to_islands_num = 0;
island_store->items_to_islands = nullptr;
island_store->island_type = MISLAND_TYPE_NONE;
island_store->islands_num = 0;
island_store->islands = nullptr;
island_store->innercut_type = MISLAND_TYPE_NONE;
island_store->innercuts = nullptr;
if (island_store->mem) {
BLI_memarena_clear(island_store->mem);
}
island_store->islands_num_alloc = 0;
}
void BKE_mesh_loop_islands_free(MeshIslandStore *island_store)
{
if (island_store->mem) {
BLI_memarena_free(island_store->mem);
island_store->mem = nullptr;
}
}
void BKE_mesh_loop_islands_add(MeshIslandStore *island_store,
const int item_num,
const int *items_indices,
const int num_island_items,
int *island_item_indices,
const int num_innercut_items,
int *innercut_item_indices)
{
MemArena *mem = island_store->mem;
MeshElemMap *isld, *innrcut;
const int curr_island_idx = island_store->islands_num++;
const size_t curr_num_islands = size_t(island_store->islands_num);
int i = item_num;
while (i--) {
island_store->items_to_islands[items_indices[i]] = curr_island_idx;
}
if (UNLIKELY(curr_num_islands > island_store->islands_num_alloc)) {
MeshElemMap **islds, **innrcuts;
island_store->islands_num_alloc *= 2;
islds = static_cast<MeshElemMap **>(
BLI_memarena_alloc(mem, sizeof(*islds) * island_store->islands_num_alloc));
memcpy(islds, island_store->islands, sizeof(*islds) * (curr_num_islands - 1));
island_store->islands = islds;
innrcuts = static_cast<MeshElemMap **>(
BLI_memarena_alloc(mem, sizeof(*innrcuts) * island_store->islands_num_alloc));
memcpy(innrcuts, island_store->innercuts, sizeof(*innrcuts) * (curr_num_islands - 1));
island_store->innercuts = innrcuts;
}
island_store->islands[curr_island_idx] = isld = static_cast<MeshElemMap *>(
BLI_memarena_alloc(mem, sizeof(*isld)));
isld->count = num_island_items;
isld->indices = static_cast<int *>(
BLI_memarena_alloc(mem, sizeof(*isld->indices) * size_t(num_island_items)));
memcpy(isld->indices, island_item_indices, sizeof(*isld->indices) * size_t(num_island_items));
island_store->innercuts[curr_island_idx] = innrcut = static_cast<MeshElemMap *>(
BLI_memarena_alloc(mem, sizeof(*innrcut)));
innrcut->count = num_innercut_items;
innrcut->indices = static_cast<int *>(
BLI_memarena_alloc(mem, sizeof(*innrcut->indices) * size_t(num_innercut_items)));
memcpy(innrcut->indices,
innercut_item_indices,
sizeof(*innrcut->indices) * size_t(num_innercut_items));
}
static bool mesh_calc_islands_loop_face_uv(const int totedge,
const bool *uv_seams,
const blender::OffsetIndices<int> faces,
const int *corner_verts,
const int *corner_edges,
const int corners_num,
const float (*luvs)[2],
MeshIslandStore *r_island_store)
{
using namespace blender;
int *face_groups = nullptr;
int num_face_groups;
int *face_indices;
int *loop_indices;
int num_pidx, num_lidx;
/* Those are used to detect 'inner cuts', i.e. edges that are boundaries,
* and yet have two or more faces of a same group using them
* (typical case: seam used to unwrap properly a cylinder). */
BLI_bitmap *edge_boundaries = nullptr;
int num_edge_boundaries = 0;
char *edge_boundary_count = nullptr;
int *edge_innercut_indices = nullptr;
int num_einnercuts = 0;
int grp_idx;
BKE_mesh_loop_islands_clear(r_island_store);
BKE_mesh_loop_islands_init(
r_island_store, MISLAND_TYPE_LOOP, corners_num, MISLAND_TYPE_POLY, MISLAND_TYPE_EDGE);
Array<int> edge_to_face_offsets;
Array<int> edge_to_face_indices;
const GroupedSpan<int> edge_to_face_map = bke::mesh::build_edge_to_face_map(
faces, {corner_edges, corners_num}, totedge, edge_to_face_offsets, edge_to_face_indices);
Array<int> edge_to_corner_offsets;
Array<int> edge_to_corner_indices;
GroupedSpan<int> edge_to_corner_map;
if (luvs) {
edge_to_corner_map = bke::mesh::build_edge_to_corner_map(
{corner_edges, corners_num}, totedge, edge_to_corner_offsets, edge_to_corner_indices);
}
/* TODO: I'm not sure edge seam flag is enough to define UV islands?
* Maybe we should also consider UV-maps values
* themselves (i.e. different UV-edges for a same mesh-edge => boundary edge too?).
* Would make things much more complex though,
* and each UVMap would then need its own mesh mapping, not sure we want that at all!
*/
auto mesh_check_island_boundary_uv = [&](const int /*face_index*/,
const int corner,
const int edge_index,
const int /*edge_user_count*/,
const Span<int> /*edge_face_map_elem*/) -> bool {
if (luvs) {
const Span<int> edge_to_corners = edge_to_corner_map[corner_edges[corner]];
BLI_assert(edge_to_corners.size() >= 2 && (edge_to_corners.size() % 2) == 0);
const int v1 = corner_verts[edge_to_corners[0]];
const int v2 = corner_verts[edge_to_corners[1]];
const float *uvco_v1 = luvs[edge_to_corners[0]];
const float *uvco_v2 = luvs[edge_to_corners[1]];
for (int i = 2; i < edge_to_corners.size(); i += 2) {
if (corner_verts[edge_to_corners[i]] == v1) {
if (!equals_v2v2(uvco_v1, luvs[edge_to_corners[i]]) ||
!equals_v2v2(uvco_v2, luvs[edge_to_corners[i + 1]]))
{
return true;
}
}
else {
BLI_assert(corner_verts[edge_to_corners[i]] == v2);
UNUSED_VARS_NDEBUG(v2);
if (!equals_v2v2(uvco_v2, luvs[edge_to_corners[i]]) ||
!equals_v2v2(uvco_v1, luvs[edge_to_corners[i + 1]]))
{
return true;
}
}
}
return false;
}
/* Edge is UV boundary if tagged as seam. */
return uv_seams && uv_seams[edge_index];
};
face_edge_loop_islands_calc(totedge,
0,
faces,
{corner_edges, corners_num},
{},
edge_to_face_map,
{},
false,
false,
mesh_check_island_boundary_uv,
&face_groups,
&num_face_groups,
&edge_boundaries,
&num_edge_boundaries);
if (!num_face_groups) {
if (num_edge_boundaries) {
MEM_freeN(edge_boundaries);
}
return false;
}
if (num_edge_boundaries) {
edge_boundary_count = MEM_malloc_arrayN<char>(size_t(totedge), __func__);
edge_innercut_indices = MEM_malloc_arrayN<int>(size_t(num_edge_boundaries), __func__);
}
face_indices = MEM_malloc_arrayN<int>(size_t(faces.size()), __func__);
loop_indices = MEM_malloc_arrayN<int>(size_t(corners_num), __func__);
/* NOTE: here we ignore '0' invalid group - this should *never* happen in this case anyway? */
for (grp_idx = 1; grp_idx <= num_face_groups; grp_idx++) {
num_pidx = num_lidx = 0;
if (num_edge_boundaries) {
num_einnercuts = 0;
memset(edge_boundary_count, 0, sizeof(*edge_boundary_count) * size_t(totedge));
}
for (const int64_t p_idx : faces.index_range()) {
if (face_groups[p_idx] != grp_idx) {
continue;
}
face_indices[num_pidx++] = int(p_idx);
for (const int64_t corner : faces[p_idx]) {
const int edge_i = corner_edges[corner];
loop_indices[num_lidx++] = int(corner);
if (num_edge_boundaries && BLI_BITMAP_TEST(edge_boundaries, edge_i) &&
(edge_boundary_count[edge_i] < 2))
{
edge_boundary_count[edge_i]++;
if (edge_boundary_count[edge_i] == 2) {
edge_innercut_indices[num_einnercuts++] = edge_i;
}
}
}
}
BKE_mesh_loop_islands_add(r_island_store,
num_lidx,
loop_indices,
num_pidx,
face_indices,
num_einnercuts,
edge_innercut_indices);
}
MEM_freeN(face_indices);
MEM_freeN(loop_indices);
MEM_freeN(face_groups);
if (num_edge_boundaries) {
MEM_freeN(edge_boundaries);
}
if (num_edge_boundaries) {
MEM_freeN(edge_boundary_count);
MEM_freeN(edge_innercut_indices);
}
return true;
}
bool BKE_mesh_calc_islands_loop_face_edgeseam(const float (*vert_positions)[3],
const int totvert,
const blender::int2 *edges,
const int totedge,
const bool *uv_seams,
const blender::OffsetIndices<int> faces,
const int *corner_verts,
const int *corner_edges,
const int corners_num,
MeshIslandStore *r_island_store)
{
UNUSED_VARS(vert_positions, totvert, edges);
return mesh_calc_islands_loop_face_uv(
totedge, uv_seams, faces, corner_verts, corner_edges, corners_num, nullptr, r_island_store);
}
bool BKE_mesh_calc_islands_loop_face_uvmap(float (*vert_positions)[3],
const int totvert,
blender::int2 *edges,
const int totedge,
const bool *uv_seams,
const blender::OffsetIndices<int> faces,
const int *corner_verts,
const int *corner_edges,
const int corners_num,
const float (*luvs)[2],
MeshIslandStore *r_island_store)
{
UNUSED_VARS(vert_positions, totvert, edges);
BLI_assert(luvs != nullptr);
return mesh_calc_islands_loop_face_uv(
totedge, uv_seams, faces, corner_verts, corner_edges, corners_num, luvs, r_island_store);
}
/** \} */