1 files changed, 131 insertions, 0 deletions
diff --git a/source/blender/io/wavefront_obj/exporter/obj_export_mesh.hh b/source/blender/io/wavefront_obj/exporter/obj_export_mesh.hh
new file mode 100644
index 00000000000..d72dd76d447
--- /dev/null
+++ b/source/blender/io/wavefront_obj/exporter/obj_export_mesh.hh
@@ -0,0 +1,131 @@
+/*
+ * 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 <optional>
+
+#include "BLI_float3.hh"
+#include "BLI_utility_mixins.hh"
+#include "BLI_vector.hh"
+
+#include "bmesh.h"
+#include "bmesh_tools.h"
+
+#include "DNA_material_types.h"
+#include "DNA_mesh_types.h"
+#include "DNA_meshdata_types.h"
+
+#include "IO_wavefront_obj.h"
+
+namespace blender::io::obj {
+/* Denote absence for usually non-negative numbers. */
+const int NOT_FOUND = -1;
+/* Any negative number other than `NOT_FOUND` to initialise usually non-negative numbers. */
+const int NEGATIVE_INIT = -10;
+
+/**
+ * #std::unique_ptr deleter for BMesh.
+ */
+struct CustomBMeshDeleter {
+  void operator()(BMesh *bmesh)
+  {
+    if (bmesh) {
+      BM_mesh_free(bmesh);
+    }
+  }
+};
+
+using unique_bmesh_ptr = std::unique_ptr<BMesh, CustomBMeshDeleter>;
+
+class OBJMesh : NonCopyable {
+ private:
+  Object *export_object_eval_;
+  Mesh *export_mesh_eval_;
+  /**
+   * For curves which are converted to mesh, and triangulated meshes, a new mesh is allocated.
+   */
+  bool mesh_eval_needs_free_ = false;
+  /**
+   * Final transform of an object obtained from export settings (up_axis, forward_axis) and the
+   * object's world transform matrix.
+   */
+  float world_and_axes_transform_[4][4];
+
+  /**
+   * Total UV vertices in a mesh's texture map.
+   */
+  int tot_uv_vertices_ = 0;
+  /**
+   * Per-polygon-per-vertex UV vertex indices.
+   */
+  Vector<Vector<int>> uv_indices_;
+  /**
+   * Total smooth groups in an object.
+   */
+  int tot_smooth_groups_ = NEGATIVE_INIT;
+  /**
+   * Polygon aligned array of their smooth groups.
+   */
+  int *poly_smooth_groups_ = nullptr;
+
+ public:
+  OBJMesh(Depsgraph *depsgraph, const OBJExportParams &export_params, Object *mesh_object);
+  ~OBJMesh();
+
+  int tot_vertices() const;
+  int tot_polygons() const;
+  int tot_uv_vertices() const;
+  int tot_edges() const;
+
+  int16_t tot_materials() const;
+  const Material *get_object_material(const int16_t mat_nr) const;
+  int16_t ith_poly_matnr(const int poly_index) const;
+
+  void ensure_mesh_normals() const;
+  void ensure_mesh_edges() const;
+
+  void calc_smooth_groups(const bool use_bitflags);
+  int ith_smooth_group(const int poly_index) const;
+  bool is_ith_poly_smooth(const int poly_index) const;
+
+  const char *get_object_name() const;
+  const char *get_object_mesh_name() const;
+  const char *get_object_material_name(const int16_t mat_nr) const;
+
+  float3 calc_vertex_coords(const int vert_index, const float scaling_factor) const;
+  Vector<int> calc_poly_vertex_indices(const int poly_index) const;
+  void store_uv_coords_and_indices(Vector<std::array<float, 2>> &r_uv_coords);
+  Span<int> calc_poly_uv_indices(const int poly_index) const;
+  float3 calc_poly_normal(const int poly_index) const;
+  std::pair<int, Vector<int>> calc_poly_normal_indices(const int poly_index,
+                                                       const int object_tot_prev_normals) const;
+  void calc_loop_normals(const int poly_index, Vector<float3> &r_loop_normals) const;
+  int16_t get_poly_deform_group_index(const int poly_index) const;
+  const char *get_poly_deform_group_name(const int16_t def_group_index) const;
+
+  std::optional<std::array<int, 2>> calc_loose_edge_vert_indices(const int edge_index) const;
+
+ private:
+  void free_mesh_if_needed();
+  std::pair<Mesh *, bool> triangulate_mesh_eval();
+  void set_world_axes_transform(const eTransformAxisForward forward, const eTransformAxisUp up);
+};
+}  // namespace blender::io::obj