diff options
4 files changed, 59 insertions, 5 deletions
diff --git a/source/blender/io/wavefront_obj/exporter/obj_export_file_writer.cc b/source/blender/io/wavefront_obj/exporter/obj_export_file_writer.cc index 3f9fc3b1dbb..acfdaa29b52 100644 --- a/source/blender/io/wavefront_obj/exporter/obj_export_file_writer.cc +++ b/source/blender/io/wavefront_obj/exporter/obj_export_file_writer.cc @@ -308,14 +308,20 @@ void OBJWriter::write_poly_elements(FormatHandler<eFileType::OBJ> &fh, obj_mesh_data.tot_uv_vertices()); const int tot_polygons = obj_mesh_data.tot_polygons(); - obj_parallel_chunked_output(fh, tot_polygons, [&](FormatHandler<eFileType::OBJ> &buf, int i) { + obj_parallel_chunked_output(fh, tot_polygons, [&](FormatHandler<eFileType::OBJ> &buf, int idx) { + /* Polygon order for writing into the file is not necessarily the same + * as order in the mesh; it will be sorted by material indices. Remap current + * and previous indices here according to the order. */ + int prev_i = obj_mesh_data.remap_poly_index(idx - 1); + int i = obj_mesh_data.remap_poly_index(idx); + Vector<int> poly_vertex_indices = obj_mesh_data.calc_poly_vertex_indices(i); Span<int> poly_uv_indices = obj_mesh_data.calc_poly_uv_indices(i); Vector<int> poly_normal_indices = obj_mesh_data.calc_poly_normal_indices(i); /* Write smoothing group if different from previous. */ { - const int prev_group = get_smooth_group(obj_mesh_data, export_params_, i - 1); + const int prev_group = get_smooth_group(obj_mesh_data, export_params_, prev_i); const int group = get_smooth_group(obj_mesh_data, export_params_, i); if (group != prev_group) { buf.write<eOBJSyntaxElement::smooth_group>(group); @@ -324,8 +330,8 @@ void OBJWriter::write_poly_elements(FormatHandler<eFileType::OBJ> &fh, /* Write vertex group if different from previous. */ if (export_params_.export_vertex_groups) { - const int16_t prev_group = i == 0 ? NEGATIVE_INIT : - obj_mesh_data.get_poly_deform_group_index(i - 1); + const int16_t prev_group = idx == 0 ? NEGATIVE_INIT : + obj_mesh_data.get_poly_deform_group_index(prev_i); const int16_t group = obj_mesh_data.get_poly_deform_group_index(i); if (group != prev_group) { buf.write<eOBJSyntaxElement::object_group>( @@ -336,7 +342,7 @@ void OBJWriter::write_poly_elements(FormatHandler<eFileType::OBJ> &fh, /* Write material name and material group if different from previous. */ if (export_params_.export_materials && obj_mesh_data.tot_materials() > 0) { - const int16_t prev_mat = i == 0 ? NEGATIVE_INIT : obj_mesh_data.ith_poly_matnr(i - 1); + const int16_t prev_mat = idx == 0 ? NEGATIVE_INIT : obj_mesh_data.ith_poly_matnr(prev_i); const int16_t mat = obj_mesh_data.ith_poly_matnr(i); if (mat != prev_mat) { if (mat == NOT_FOUND) { diff --git a/source/blender/io/wavefront_obj/exporter/obj_export_mesh.cc b/source/blender/io/wavefront_obj/exporter/obj_export_mesh.cc index 7d3e3cd84fd..9975f300150 100644 --- a/source/blender/io/wavefront_obj/exporter/obj_export_mesh.cc +++ b/source/blender/io/wavefront_obj/exporter/obj_export_mesh.cc @@ -27,6 +27,10 @@ #include "obj_export_mesh.hh" +#ifdef WITH_TBB +# include <tbb/parallel_sort.h> +#endif + namespace blender::io::obj { OBJMesh::OBJMesh(Depsgraph *depsgraph, const OBJExportParams &export_params, Object *mesh_object) { @@ -76,6 +80,7 @@ void OBJMesh::clear() 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; @@ -193,6 +198,26 @@ void OBJMesh::calc_smooth_groups(const bool use_bitflags) 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. */ +#ifdef WITH_TBB + tbb::parallel_sort(poly_order_.begin(), poly_order_.end(), [&](int a, int b) { +#else + std::sort(poly_order_.begin(), poly_order_.end(), [&](const Vert *a, const Vert *b) { +#endif + int mat_a = mpolys[a].mat_nr; + int mat_b = mpolys[b].mat_nr; + return mat_a < mat_b; + }); +} + const Material *OBJMesh::get_object_material(const int16_t mat_nr) const { /** diff --git a/source/blender/io/wavefront_obj/exporter/obj_export_mesh.hh b/source/blender/io/wavefront_obj/exporter/obj_export_mesh.hh index 03dbd1b799f..7650a220810 100644 --- a/source/blender/io/wavefront_obj/exporter/obj_export_mesh.hh +++ b/source/blender/io/wavefront_obj/exporter/obj_export_mesh.hh @@ -95,6 +95,10 @@ class OBJMesh : NonCopyable { * Polygon aligned array of their smooth groups. */ int *poly_smooth_groups_ = nullptr; + /** + * Order in which the polygons should be written into the file (sorted by material index). + */ + Vector<int> poly_order_; public: /** @@ -218,6 +222,22 @@ class OBJMesh : NonCopyable { */ std::optional<std::array<int, 2>> calc_loose_edge_vert_indices(int edge_index) const; + /** + * Calculate the order in which the polygons should be written into the file (sorted by material + * index). + */ + void calc_poly_order(); + + /** + * Remap polygon index according to polygon writing order. + * When materials are not being written, the polygon order array + * might be empty, in which case remap is a no-op. + */ + int remap_poly_index(int i) const + { + return i < 0 || i >= poly_order_.size() ? i : poly_order_[i]; + } + private: /** * Free the mesh if _the exporter_ created it. diff --git a/source/blender/io/wavefront_obj/exporter/obj_exporter.cc b/source/blender/io/wavefront_obj/exporter/obj_exporter.cc index 2cef5192337..30670d45ef7 100644 --- a/source/blender/io/wavefront_obj/exporter/obj_exporter.cc +++ b/source/blender/io/wavefront_obj/exporter/obj_exporter.cc @@ -204,6 +204,9 @@ static void write_mesh_objects(Vector<std::unique_ptr<OBJMesh>> exportable_as_me if (export_params.export_smooth_groups) { obj.calc_smooth_groups(export_params.smooth_groups_bitflags); } + if (export_params.export_materials) { + obj.calc_poly_order(); + } if (export_params.export_normals) { obj_writer.write_poly_normals(fh, obj); } |