1 files changed, 132 insertions, 0 deletions
diff --git a/source/blender/io/wavefront_obj/exporter/obj_export_file_writer.hh b/source/blender/io/wavefront_obj/exporter/obj_export_file_writer.hh
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+++ b/source/blender/io/wavefront_obj/exporter/obj_export_file_writer.hh
@@ -0,0 +1,132 @@
+/*
+ * 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.
+ */
+
+/** \file
+ * \ingroup obj
+ */
+
+#pragma once
+
+#include "DNA_meshdata_types.h"
+
+#include "BLI_map.hh"
+#include "BLI_vector.hh"
+
+#include "IO_wavefront_obj.h"
+#include "obj_export_io.hh"
+#include "obj_export_mtl.hh"
+
+namespace blender::io::obj {
+
+class OBJCurve;
+class OBJMesh;
+/**
+ * Total vertices/ UV vertices/ normals of previous Objects
+ * should be added to the current Object's indices.
+ */
+struct IndexOffsets {
+  int vertex_offset;
+  int uv_vertex_offset;
+  int normal_offset;
+};
+
+/**
+ * Responsible for writing a .OBJ file.
+ */
+class OBJWriter : NonMovable, NonCopyable {
+ private:
+  const OBJExportParams &export_params_;
+  std::unique_ptr<FileHandler<eFileType::OBJ>> file_handler_ = nullptr;
+  IndexOffsets index_offsets_{0, 0, 0};
+
+ public:
+  OBJWriter(const char *filepath, const OBJExportParams &export_params) noexcept(false)
+      : export_params_(export_params)
+  {
+    file_handler_ = std::make_unique<FileHandler<eFileType::OBJ>>(filepath);
+  }
+
+  void write_header() const;
+
+  void write_object_name(const OBJMesh &obj_mesh_data) const;
+  void write_object_group(const OBJMesh &obj_mesh_data) const;
+  void write_mtllib_name(const StringRefNull mtl_filepath) const;
+  void write_vertex_coords(const OBJMesh &obj_mesh_data) const;
+  void write_uv_coords(OBJMesh &obj_mesh_data) const;
+  void write_poly_normals(const OBJMesh &obj_mesh_data) const;
+  int write_smooth_group(const OBJMesh &obj_mesh_data,
+                         int poly_index,
+                         const int last_poly_smooth_group) const;
+  int16_t write_poly_material(const OBJMesh &obj_mesh_data,
+                              const int poly_index,
+                              const int16_t last_poly_mat_nr,
+                              std::function<const char *(int)> matname_fn) const;
+  int16_t write_vertex_group(const OBJMesh &obj_mesh_data,
+                             const int poly_index,
+                             const int16_t last_poly_vertex_group) const;
+  void write_poly_elements(const OBJMesh &obj_mesh_data,
+                           std::function<const char *(int)> matname_fn);
+  void write_edges_indices(const OBJMesh &obj_mesh_data) const;
+  void write_nurbs_curve(const OBJCurve &obj_nurbs_data) const;
+
+  void update_index_offsets(const OBJMesh &obj_mesh_data);
+
+ private:
+  using func_vert_uv_normal_indices = void (OBJWriter::*)(Span<int> vert_indices,
+                                                          Span<int> uv_indices,
+                                                          Span<int> normal_indices) const;
+  func_vert_uv_normal_indices get_poly_element_writer(const int total_uv_vertices) const;
+
+  void write_vert_uv_normal_indices(Span<int> vert_indices,
+                                    Span<int> uv_indices,
+                                    Span<int> normal_indices) const;
+  void write_vert_normal_indices(Span<int> vert_indices,
+                                 Span<int> /*uv_indices*/,
+                                 Span<int> normal_indices) const;
+  void write_vert_uv_indices(Span<int> vert_indices,
+                             Span<int> uv_indices,
+                             Span<int> /*normal_indices*/) const;
+  void write_vert_indices(Span<int> vert_indices,
+                          Span<int> /*uv_indices*/,
+                          Span<int> /*normal_indices*/) const;
+};
+
+/**
+ * Responsible for writing a .MTL file.
+ */
+class MTLWriter : NonMovable, NonCopyable {
+ private:
+  std::unique_ptr<FileHandler<eFileType::MTL>> file_handler_ = nullptr;
+  std::string mtl_filepath_;
+  Vector<MTLMaterial> mtlmaterials_;
+  /* Map from a Material* to an index into mtlmaterials_. */
+  Map<const Material *, int> material_map_;
+
+ public:
+  MTLWriter(const char *obj_filepath) noexcept(false);
+
+  void write_header(const char *blen_filepath) const;
+  void write_materials();
+  StringRefNull mtl_file_path() const;
+  Vector<int> add_materials(const OBJMesh &mesh_to_export);
+  const char *mtlmaterial_name(int index);
+
+ private:
+  void write_bsdf_properties(const MTLMaterial &mtl_material);
+  void write_texture_map(const MTLMaterial &mtl_material,
+                         const Map<const eMTLSyntaxElement, tex_map_XX>::Item &texture_map);
+};
+}  // namespace blender::io::obj