[Bf-blender-cvs] [641f859f882] soc-2020-io-performance: Material: Disambiguate mat_nr + 1.

[Ankit Meel]

Commit: 641f859f882ccd51e2d580a3e4390af103a885e8
Author: Ankit Meel
Date:   Wed Sep 16 14:27:09 2020 +0530
Branches: soc-2020-io-performance
https://developer.blender.org/rB641f859f882ccd51e2d580a3e4390af103a885e8

Material: Disambiguate mat_nr + 1.

===================================================================

M	source/blender/io/wavefront_obj/intern/obj_export_mesh.cc
M	source/blender/io/wavefront_obj/intern/obj_export_mtl.cc

===================================================================

diff --git a/source/blender/io/wavefront_obj/intern/obj_export_mesh.cc b/source/blender/io/wavefront_obj/intern/obj_export_mesh.cc
index 3dfbaa76688..1109a017a04 100644
--- a/source/blender/io/wavefront_obj/intern/obj_export_mesh.cc
+++ b/source/blender/io/wavefront_obj/intern/obj_export_mesh.cc
@@ -234,7 +234,8 @@ void OBJMesh::calc_smooth_groups(const bool use_bitflags)
  */
 const Material *OBJMesh::get_object_material(const short mat_nr) const
 {
-  return BKE_object_material_get(export_object_eval_, mat_nr);
+  /* "+ 1" as material getter needs one-based indices.  */
+  return BKE_object_material_get(export_object_eval_, mat_nr + 1);
 }
 
 bool OBJMesh::is_ith_poly_smooth(const uint poly_index) const
@@ -271,17 +272,18 @@ const char *OBJMesh::get_object_mesh_name() const
 }
 
 /**
- * Get object's material (at the given index) name.
+ * Get object's material (at the given index) name. The given index should be zero-based.
  */
-const char *OBJMesh::get_object_material_name(short mat_nr) const
+const char *OBJMesh::get_object_material_name(const short mat_nr) const
 {
-  const Material *mat = BKE_object_material_get(export_object_eval_, mat_nr);
-#ifdef DEBUG
+  const Material *mat = get_object_material(mat_nr);
   if (!mat) {
+#ifdef DEBUG
     std::cerr << "Material not found for mat_nr = " << mat_nr << std::endl;
-  }
 #endif
-  return mat ? mat->id.name + 2 : nullptr;
+    return nullptr;
+  }
+  return mat->id.name + 2;
 }
 
 /**
diff --git a/source/blender/io/wavefront_obj/intern/obj_export_mtl.cc b/source/blender/io/wavefront_obj/intern/obj_export_mtl.cc
index 8d7d0111a71..02b68767a80 100644
--- a/source/blender/io/wavefront_obj/intern/obj_export_mtl.cc
+++ b/source/blender/io/wavefront_obj/intern/obj_export_mtl.cc
@@ -314,12 +314,12 @@ void MaterialWrap::store_image_textures(MTLMaterial &r_mtl_mat) const
  */
 void MaterialWrap::fill_materials()
 {
-    export_mtl_ = obj_mesh_data_.get_object_material(i + 1);
   for (short i = 0; i < obj_mesh_data_.tot_materials(); i++) {
+    export_mtl_ = obj_mesh_data_.get_object_material(i);
     if (!export_mtl_) {
       continue;
     }
-    r_mtl_materials_[i].name = obj_mesh_data_.get_object_material_name(i + 1);
+    r_mtl_materials_[i].name = obj_mesh_data_.get_object_material_name(i);
     init_bsdf_node(obj_mesh_data_.get_object_name());
     store_bsdf_properties(r_mtl_materials_[i]);
     store_image_textures(r_mtl_materials_[i]);