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/* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup obj
*/
/* Silence warnings from copying deprecated fields. Needed for an Object copy constructor use. */
#define DNA_DEPRECATED_ALLOW
#include "BKE_customdata.h"
#include "BKE_deform.h"
#include "BKE_lib_id.h"
#include "BKE_material.h"
#include "BKE_mesh.h"
#include "BKE_mesh_mapping.h"
#include "BKE_object.h"
#include "BLI_listbase.h"
#include "BLI_map.hh"
#include "BLI_math.h"
#include "BLI_sort.hh"
#include "DEG_depsgraph_query.h"
#include "DNA_material_types.h"
#include "DNA_mesh_types.h"
#include "DNA_modifier_types.h"
#include "DNA_object_types.h"
#include "obj_export_mesh.hh"
namespace blender::io::obj {
OBJMesh::OBJMesh(Depsgraph *depsgraph, const OBJExportParams &export_params, Object *mesh_object)
{
/* We need to copy the object because it may be in temporary space. */
Object *obj_eval = DEG_get_evaluated_object(depsgraph, mesh_object);
export_object_eval_ = dna::shallow_copy(*obj_eval);
export_mesh_eval_ = export_params.apply_modifiers ?
BKE_object_get_evaluated_mesh(&export_object_eval_) :
BKE_object_get_pre_modified_mesh(&export_object_eval_);
mesh_eval_needs_free_ = false;
if (!export_mesh_eval_) {
/* Curves and NURBS surfaces need a new mesh when they're
* exported in the form of vertices and edges.
*/
export_mesh_eval_ = BKE_mesh_new_from_object(depsgraph, &export_object_eval_, true, true);
/* Since a new mesh been allocated, it needs to be freed in the destructor. */
mesh_eval_needs_free_ = true;
}
if (export_params.export_triangulated_mesh && ELEM(export_object_eval_.type, OB_MESH, OB_SURF)) {
std::tie(export_mesh_eval_, mesh_eval_needs_free_) = triangulate_mesh_eval();
}
set_world_axes_transform(export_params.forward_axis, export_params.up_axis);
}
/**
* Free new meshes allocated for triangulated meshes, or Curve converted to Mesh.
*/
OBJMesh::~OBJMesh()
{
clear();
}
void OBJMesh::free_mesh_if_needed()
{
if (mesh_eval_needs_free_ && export_mesh_eval_) {
BKE_id_free(nullptr, export_mesh_eval_);
export_mesh_eval_ = nullptr;
mesh_eval_needs_free_ = false;
}
}
void OBJMesh::clear()
{
free_mesh_if_needed();
uv_indices_.clear_and_make_inline();
uv_coords_.clear_and_make_inline();
loop_to_normal_index_.clear_and_make_inline();
normal_coords_.clear_and_make_inline();
poly_order_.clear_and_make_inline();
if (poly_smooth_groups_) {
MEM_freeN(poly_smooth_groups_);
poly_smooth_groups_ = nullptr;
}
}
std::pair<Mesh *, bool> OBJMesh::triangulate_mesh_eval()
{
if (export_mesh_eval_->totpoly <= 0) {
return {export_mesh_eval_, false};
}
const BMeshCreateParams bm_create_params = {false};
BMeshFromMeshParams bm_convert_params{};
bm_convert_params.calc_face_normal = true;
bm_convert_params.calc_vert_normal = true;
bm_convert_params.add_key_index = false;
bm_convert_params.use_shapekey = false;
/* Lower threshold where triangulation of a polygon starts, i.e. a quadrilateral will be
* triangulated here. */
const int triangulate_min_verts = 4;
unique_bmesh_ptr bmesh(
BKE_mesh_to_bmesh_ex(export_mesh_eval_, &bm_create_params, &bm_convert_params));
BM_mesh_triangulate(bmesh.get(),
MOD_TRIANGULATE_NGON_BEAUTY,
MOD_TRIANGULATE_QUAD_SHORTEDGE,
triangulate_min_verts,
false,
nullptr,
nullptr,
nullptr);
Mesh *triangulated = BKE_mesh_from_bmesh_for_eval_nomain(
bmesh.get(), nullptr, export_mesh_eval_);
free_mesh_if_needed();
return {triangulated, true};
}
void OBJMesh::set_world_axes_transform(const eTransformAxisForward forward,
const eTransformAxisUp up)
{
float axes_transform[3][3];
unit_m3(axes_transform);
/* +Y-forward and +Z-up are the default Blender axis settings. */
mat3_from_axis_conversion(OBJ_AXIS_Y_FORWARD, OBJ_AXIS_Z_UP, forward, up, axes_transform);
/* mat3_from_axis_conversion returns a transposed matrix! */
transpose_m3(axes_transform);
mul_m4_m3m4(world_and_axes_transform_, axes_transform, export_object_eval_.obmat);
/* mul_m4_m3m4 does not transform last row of obmat, i.e. location data. */
mul_v3_m3v3(world_and_axes_transform_[3], axes_transform, export_object_eval_.obmat[3]);
world_and_axes_transform_[3][3] = export_object_eval_.obmat[3][3];
/* Normals need inverse transpose of the regular matrix to handle non-uniform scale. */
float normal_matrix[3][3];
copy_m3_m4(normal_matrix, world_and_axes_transform_);
invert_m3_m3(world_and_axes_normal_transform_, normal_matrix);
transpose_m3(world_and_axes_normal_transform_);
mirrored_transform_ = determinant_m3_array(world_and_axes_normal_transform_) < 0;
}
int OBJMesh::tot_vertices() const
{
return export_mesh_eval_->totvert;
}
int OBJMesh::tot_polygons() const
{
return export_mesh_eval_->totpoly;
}
int OBJMesh::tot_uv_vertices() const
{
return tot_uv_vertices_;
}
int OBJMesh::tot_edges() const
{
return export_mesh_eval_->totedge;
}
int16_t OBJMesh::tot_materials() const
{
return export_mesh_eval_->totcol;
}
int OBJMesh::tot_normal_indices() const
{
return tot_normal_indices_;
}
int OBJMesh::ith_smooth_group(const int poly_index) const
{
/* Calculate smooth groups first: #OBJMesh::calc_smooth_groups. */
BLI_assert(tot_smooth_groups_ != -NEGATIVE_INIT);
BLI_assert(poly_smooth_groups_);
return poly_smooth_groups_[poly_index];
}
void OBJMesh::ensure_mesh_normals() const
{
BKE_mesh_calc_normals_split(export_mesh_eval_);
}
void OBJMesh::ensure_mesh_edges() const
{
BKE_mesh_calc_edges(export_mesh_eval_, true, false);
BKE_mesh_calc_edges_loose(export_mesh_eval_);
}
void OBJMesh::calc_smooth_groups(const bool use_bitflags)
{
poly_smooth_groups_ = BKE_mesh_calc_smoothgroups(export_mesh_eval_->medge,
export_mesh_eval_->totedge,
export_mesh_eval_->mpoly,
export_mesh_eval_->totpoly,
export_mesh_eval_->mloop,
export_mesh_eval_->totloop,
&tot_smooth_groups_,
use_bitflags);
}
void OBJMesh::calc_poly_order()
{
const int tot_polys = tot_polygons();
poly_order_.resize(tot_polys);
for (int i = 0; i < tot_polys; ++i) {
poly_order_[i] = i;
}
const MPoly *mpolys = export_mesh_eval_->mpoly;
/* Sort polygons by their material index. */
blender::parallel_sort(poly_order_.begin(), poly_order_.end(), [&](int a, int b) {
int mat_a = mpolys[a].mat_nr;
int mat_b = mpolys[b].mat_nr;
if (mat_a != mat_b) {
return mat_a < mat_b;
}
return a < b;
});
}
const Material *OBJMesh::get_object_material(const int16_t mat_nr) const
{
/**
* The const_cast is safe here because BKE_object_material_get won't change the object
* but it is a big can of worms to fix the declaration of that function right now.
*
* The call uses "+ 1" as material getter needs one-based indices.
*/
Object *obj = const_cast<Object *>(&export_object_eval_);
const Material *r_mat = BKE_object_material_get(obj, mat_nr + 1);
return r_mat;
}
bool OBJMesh::is_ith_poly_smooth(const int poly_index) const
{
return export_mesh_eval_->mpoly[poly_index].flag & ME_SMOOTH;
}
int16_t OBJMesh::ith_poly_matnr(const int poly_index) const
{
BLI_assert(poly_index < export_mesh_eval_->totpoly);
const int16_t r_mat_nr = export_mesh_eval_->mpoly[poly_index].mat_nr;
return r_mat_nr >= 0 ? r_mat_nr : NOT_FOUND;
}
const char *OBJMesh::get_object_name() const
{
return export_object_eval_.id.name + 2;
}
const char *OBJMesh::get_object_mesh_name() const
{
return export_mesh_eval_->id.name + 2;
}
const char *OBJMesh::get_object_material_name(const int16_t mat_nr) const
{
const Material *mat = get_object_material(mat_nr);
if (!mat) {
return nullptr;
}
return mat->id.name + 2;
}
float3 OBJMesh::calc_vertex_coords(const int vert_index, const float scaling_factor) const
{
float3 r_coords;
copy_v3_v3(r_coords, export_mesh_eval_->mvert[vert_index].co);
mul_m4_v3(world_and_axes_transform_, r_coords);
mul_v3_fl(r_coords, scaling_factor);
return r_coords;
}
Vector<int> OBJMesh::calc_poly_vertex_indices(const int poly_index) const
{
const MPoly &mpoly = export_mesh_eval_->mpoly[poly_index];
const MLoop *mloop = &export_mesh_eval_->mloop[mpoly.loopstart];
const int totloop = mpoly.totloop;
Vector<int> r_poly_vertex_indices(totloop);
for (int loop_index = 0; loop_index < totloop; loop_index++) {
r_poly_vertex_indices[loop_index] = mloop[loop_index].v;
}
return r_poly_vertex_indices;
}
void OBJMesh::store_uv_coords_and_indices()
{
const MPoly *mpoly = export_mesh_eval_->mpoly;
const MLoop *mloop = export_mesh_eval_->mloop;
const int totpoly = export_mesh_eval_->totpoly;
const int totvert = export_mesh_eval_->totvert;
const MLoopUV *mloopuv = static_cast<const MLoopUV *>(
CustomData_get_layer(&export_mesh_eval_->ldata, CD_MLOOPUV));
if (!mloopuv) {
tot_uv_vertices_ = 0;
return;
}
const float limit[2] = {STD_UV_CONNECT_LIMIT, STD_UV_CONNECT_LIMIT};
UvVertMap *uv_vert_map = BKE_mesh_uv_vert_map_create(
mpoly, mloop, mloopuv, totpoly, totvert, limit, false, false);
uv_indices_.resize(totpoly);
/* At least total vertices of a mesh will be present in its texture map. So
* reserve minimum space early. */
uv_coords_.reserve(totvert);
tot_uv_vertices_ = 0;
for (int vertex_index = 0; vertex_index < totvert; vertex_index++) {
const UvMapVert *uv_vert = BKE_mesh_uv_vert_map_get_vert(uv_vert_map, vertex_index);
for (; uv_vert; uv_vert = uv_vert->next) {
if (uv_vert->separate) {
tot_uv_vertices_ += 1;
}
const int vertices_in_poly = mpoly[uv_vert->poly_index].totloop;
/* Store UV vertex coordinates. */
uv_coords_.resize(tot_uv_vertices_);
const int loopstart = mpoly[uv_vert->poly_index].loopstart;
Span<float> vert_uv_coords(mloopuv[loopstart + uv_vert->loop_of_poly_index].uv, 2);
uv_coords_[tot_uv_vertices_ - 1] = float2(vert_uv_coords[0], vert_uv_coords[1]);
/* Store UV vertex indices. */
uv_indices_[uv_vert->poly_index].resize(vertices_in_poly);
/* Keep indices zero-based and let the writer handle the "+ 1" as per OBJ spec. */
uv_indices_[uv_vert->poly_index][uv_vert->loop_of_poly_index] = tot_uv_vertices_ - 1;
}
}
BKE_mesh_uv_vert_map_free(uv_vert_map);
}
Span<int> OBJMesh::calc_poly_uv_indices(const int poly_index) const
{
if (uv_indices_.size() <= 0) {
return {};
}
BLI_assert(poly_index < export_mesh_eval_->totpoly);
BLI_assert(poly_index < uv_indices_.size());
return uv_indices_[poly_index];
}
float3 OBJMesh::calc_poly_normal(const int poly_index) const
{
float3 r_poly_normal;
const MPoly &poly = export_mesh_eval_->mpoly[poly_index];
const MLoop &mloop = export_mesh_eval_->mloop[poly.loopstart];
const MVert &mvert = *(export_mesh_eval_->mvert);
BKE_mesh_calc_poly_normal(&poly, &mloop, &mvert, r_poly_normal);
mul_m3_v3(world_and_axes_normal_transform_, r_poly_normal);
normalize_v3(r_poly_normal);
return r_poly_normal;
}
/** Round \a f to \a round_digits decimal digits. */
static float round_float_to_n_digits(const float f, int round_digits)
{
float scale = powf(10.0, round_digits);
return ceilf((scale * f - 0.49999999f)) / scale;
}
static float3 round_float3_to_n_digits(const float3 &v, int round_digits)
{
float3 ans;
ans.x = round_float_to_n_digits(v.x, round_digits);
ans.y = round_float_to_n_digits(v.y, round_digits);
ans.z = round_float_to_n_digits(v.z, round_digits);
return ans;
}
void OBJMesh::store_normal_coords_and_indices()
{
/* We'll round normal components to 4 digits.
* This will cover up some minor differences
* between floating point calculations on different platforms.
* Since normals are normalized, there will be no perceptible loss
* of precision when rounding to 4 digits. */
constexpr int round_digits = 4;
int cur_normal_index = 0;
Map<float3, int> normal_to_index;
/* We don't know how many unique normals there will be, but this is a guess. */
normal_to_index.reserve(export_mesh_eval_->totpoly);
loop_to_normal_index_.resize(export_mesh_eval_->totloop);
loop_to_normal_index_.fill(-1);
const float(*lnors)[3] = static_cast<const float(*)[3]>(
CustomData_get_layer(&export_mesh_eval_->ldata, CD_NORMAL));
for (int poly_index = 0; poly_index < export_mesh_eval_->totpoly; ++poly_index) {
const MPoly &mpoly = export_mesh_eval_->mpoly[poly_index];
bool need_per_loop_normals = lnors != nullptr || (mpoly.flag & ME_SMOOTH);
if (need_per_loop_normals) {
for (int loop_of_poly = 0; loop_of_poly < mpoly.totloop; ++loop_of_poly) {
float3 loop_normal;
int loop_index = mpoly.loopstart + loop_of_poly;
BLI_assert(loop_index < export_mesh_eval_->totloop);
copy_v3_v3(loop_normal, lnors[loop_index]);
mul_m3_v3(world_and_axes_normal_transform_, loop_normal);
normalize_v3(loop_normal);
float3 rounded_loop_normal = round_float3_to_n_digits(loop_normal, round_digits);
int loop_norm_index = normal_to_index.lookup_default(rounded_loop_normal, -1);
if (loop_norm_index == -1) {
loop_norm_index = cur_normal_index++;
normal_to_index.add(rounded_loop_normal, loop_norm_index);
normal_coords_.append(rounded_loop_normal);
}
loop_to_normal_index_[loop_index] = loop_norm_index;
}
}
else {
float3 poly_normal = calc_poly_normal(poly_index);
float3 rounded_poly_normal = round_float3_to_n_digits(poly_normal, round_digits);
int poly_norm_index = normal_to_index.lookup_default(rounded_poly_normal, -1);
if (poly_norm_index == -1) {
poly_norm_index = cur_normal_index++;
normal_to_index.add(rounded_poly_normal, poly_norm_index);
normal_coords_.append(rounded_poly_normal);
}
for (int i = 0; i < mpoly.totloop; ++i) {
int loop_index = mpoly.loopstart + i;
BLI_assert(loop_index < export_mesh_eval_->totloop);
loop_to_normal_index_[loop_index] = poly_norm_index;
}
}
}
tot_normal_indices_ = cur_normal_index;
}
Vector<int> OBJMesh::calc_poly_normal_indices(const int poly_index) const
{
if (loop_to_normal_index_.is_empty()) {
return {};
}
const MPoly &mpoly = export_mesh_eval_->mpoly[poly_index];
const int totloop = mpoly.totloop;
Vector<int> r_poly_normal_indices(totloop);
for (int poly_loop_index = 0; poly_loop_index < totloop; poly_loop_index++) {
int loop_index = mpoly.loopstart + poly_loop_index;
r_poly_normal_indices[poly_loop_index] = loop_to_normal_index_[loop_index];
}
return r_poly_normal_indices;
}
int OBJMesh::tot_deform_groups() const
{
if (!BKE_object_supports_vertex_groups(&export_object_eval_)) {
return 0;
}
return BKE_object_defgroup_count(&export_object_eval_);
}
int16_t OBJMesh::get_poly_deform_group_index(const int poly_index,
MutableSpan<float> group_weights) const
{
BLI_assert(poly_index < export_mesh_eval_->totpoly);
BLI_assert(group_weights.size() == BKE_object_defgroup_count(&export_object_eval_));
const MDeformVert *dvert_layer = static_cast<const MDeformVert *>(
CustomData_get_layer(&export_mesh_eval_->vdata, CD_MDEFORMVERT));
if (!dvert_layer) {
return NOT_FOUND;
}
group_weights.fill(0);
bool found_any_group = false;
const MPoly &mpoly = export_mesh_eval_->mpoly[poly_index];
const MLoop *mloop = &export_mesh_eval_->mloop[mpoly.loopstart];
for (int loop_i = 0; loop_i < mpoly.totloop; ++loop_i, ++mloop) {
const MDeformVert &dvert = dvert_layer[mloop->v];
for (int weight_i = 0; weight_i < dvert.totweight; ++weight_i) {
const auto group = dvert.dw[weight_i].def_nr;
if (group < group_weights.size()) {
group_weights[group] += dvert.dw[weight_i].weight;
found_any_group = true;
}
}
}
if (!found_any_group) {
return NOT_FOUND;
}
/* Index of the group with maximum vertices. */
int16_t max_idx = std::max_element(group_weights.begin(), group_weights.end()) -
group_weights.begin();
return max_idx;
}
const char *OBJMesh::get_poly_deform_group_name(const int16_t def_group_index) const
{
const bDeformGroup &vertex_group = *(static_cast<bDeformGroup *>(
BLI_findlink(BKE_object_defgroup_list(&export_object_eval_), def_group_index)));
return vertex_group.name;
}
std::optional<std::array<int, 2>> OBJMesh::calc_loose_edge_vert_indices(const int edge_index) const
{
const MEdge &edge = export_mesh_eval_->medge[edge_index];
if (edge.flag & ME_LOOSEEDGE) {
return std::array<int, 2>{static_cast<int>(edge.v1), static_cast<int>(edge.v2)};
}
return std::nullopt;
}
} // namespace blender::io::obj
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