source/blender/render/hydra/scene_delegate/mesh.cc

@@ -43,9 +43,9 @@ void MeshData::init()
 
 void MeshData::insert()
 {
-  if (face_vertex_counts_.empty()) {
+  //if (face_vertex_counts_.empty()) {
-    return;
+  //  return;
-  }
+  //}
 
   ID_LOG(2, "");
   scene_delegate_->GetRenderIndex().InsertRprim(
@@ -72,7 +72,7 @@ void MeshData::update()
   }
   else {
     if (id->recalc & ID_RECALC_SHADING) {
-      write_material(nullptr);
+      write_material();
       bits |= pxr::HdChangeTracker::DirtyMaterialId | pxr::HdChangeTracker::DirtyDoubleSided;
     }
     if (id->recalc & ID_RECALC_TRANSFORM) {
@@ -90,11 +90,11 @@ void MeshData::update()
     return;
   }
 
-  if (face_vertex_counts_.empty()) {
+  //if (face_vertex_counts_.empty()) {
-    /* Remove prim without faces */
+  //  /* Remove prim without faces */
-    remove();
+  //  remove();
-    return;
+  //  return;
-  }
+  //}
   ID_LOG(2, "");
   scene_delegate_->GetRenderIndex().GetChangeTracker().MarkRprimDirty(prim_id, bits);
 }
@@ -127,10 +127,11 @@ bool MeshData::update_visibility()
 
 pxr::HdMeshTopology MeshData::mesh_topology() const
 {
+  const MaterialMesh &m = material_meshes_[0];
   return pxr::HdMeshTopology(pxr::PxOsdOpenSubdivTokens->none,
                              pxr::HdTokens->rightHanded,
-                             face_vertex_counts_,
+                             m.face_vertex_counts,
-                             face_vertex_indices_);
+                             m.face_vertex_indices);
 }
 
 pxr::HdPrimvarDescriptorVector MeshData::primvar_descriptors(
@@ -158,23 +159,27 @@ pxr::HdPrimvarDescriptorVector MeshData::primvar_descriptors(
 
 pxr::SdfPath MeshData::material_id() const
 {
-  if (!mat_data_) {
+  const MaterialMesh &m = material_meshes_[0];
+  if (!m.mat_data) {
     return pxr::SdfPath();
   }
-  return mat_data_->prim_id;
+  return m.mat_data->prim_id;
 }
 
 bool MeshData::double_sided() const
 {
-  if (mat_data_) {
+  const MaterialMesh &m = material_meshes_[0];
-    return mat_data_->double_sided;
+  if (m.mat_data) {
+    return m.mat_data->double_sided;
   }
   return true;
 }
 
 void MeshData::update_double_sided(MaterialData *mat_data)
 {
-  if (mat_data_ == mat_data) {
+  MaterialMesh &m = material_meshes_[0];
+
+  if (m.mat_data == mat_data) {
     ID_LOG(2, "");
     scene_delegate_->GetRenderIndex().GetChangeTracker().MarkRprimDirty(
         prim_id, pxr::HdChangeTracker::DirtyDoubleSided);
@@ -183,12 +188,9 @@ void MeshData::update_double_sided(MaterialData *mat_data)
 
 void MeshData::write_mesh(Mesh *mesh)
 {
-  face_vertex_counts_.clear();
-  face_vertex_indices_.clear();
   vertices_.clear();
   normals_.clear();
   uvs_.clear();
-  face_material_indices_.clear();
 
   BKE_mesh_calc_normals_split(mesh);
   int tris_len = BKE_mesh_runtime_looptri_len(mesh);
@@ -196,20 +198,6 @@ void MeshData::write_mesh(Mesh *mesh)
     return;
   }
 
-  blender::Span<MLoopTri> loopTris = mesh->looptris();
-
-  /* face_vertex_counts */
-  face_vertex_counts_ = pxr::VtIntArray(tris_len, 3);
-
-  /* face_vertex_indices */
-  blender::Span<int> corner_verts = mesh->corner_verts();
-  face_vertex_indices_.reserve(loopTris.size() * 3);
-  for (MLoopTri lt : loopTris) {
-    face_vertex_indices_.push_back(corner_verts[lt.tri[0]]);
-    face_vertex_indices_.push_back(corner_verts[lt.tri[1]]);
-    face_vertex_indices_.push_back(corner_verts[lt.tri[2]]);
-  }
-
   /* vertices */
   vertices_.reserve(mesh->totvert);
   blender::Span<blender::float3> verts = mesh->vert_positions();
@@ -217,42 +205,53 @@ void MeshData::write_mesh(Mesh *mesh)
     vertices_.push_back(pxr::GfVec3f(v.x, v.y, v.z));
   }
 
+  /* material meshes */
+  material_meshes_.clear();
+  int mat_count = BKE_object_material_count_eval((Object *)id);
+  for (int i = 0; i < std::max(mat_count, 1); ++i) {
+    material_meshes_.push_back(MaterialMesh());
+  }
+
+  const int *material_indices = BKE_mesh_material_indices(mesh);
+  const int *looptri_polys = BKE_mesh_runtime_looptri_polys_ensure(mesh);
+  blender::Span<int> corner_verts = mesh->corner_verts();
+  blender::Span<MLoopTri> looptris = mesh->looptris();
+  for (size_t i = 0; i < looptris.size(); ++i) {
+    int mat_ind = material_indices ? material_indices[looptri_polys[i]] : 0;
+
+    const MLoopTri &lt = looptris[i];
+    MaterialMesh &m = material_meshes_[mat_ind];
+    m.face_vertex_counts.push_back(3);
+    m.face_vertex_indices.push_back(corner_verts[lt.tri[0]]);
+    m.face_vertex_indices.push_back(corner_verts[lt.tri[1]]);
+    m.face_vertex_indices.push_back(corner_verts[lt.tri[2]]);
+  }
+
   write_normals(mesh);
   write_uv_maps(mesh);
-  write_material(mesh);
+  write_material();
 }
 
-void MeshData::write_material(Mesh *mesh)
+void MeshData::write_material()
 {
   Object *object = (Object *)id;
-  Material *mat = nullptr;
+  for (int i = 0; i < material_meshes_.size(); ++i) {
-  if (BKE_object_material_count_eval(object) > 0) {
+    MaterialMesh &m = material_meshes_[i];
-    mat = BKE_object_material_get_eval(object, object->actcol);
+    if (m.face_vertex_counts.empty()) {
-  }
+      continue;
-
+    }
-  if (!mat) {
+    Material *mat = BKE_object_material_get_eval(object, i);
-    mat_data_ = nullptr;
+    if (!mat) {
-    return;
+      m.mat_data = nullptr;
-  }
+      continue;
-
+    }
-  pxr::SdfPath p_id = scene_delegate_->material_prim_id(mat);
+    pxr::SdfPath p_id = scene_delegate_->material_prim_id(mat);
-  mat_data_ = scene_delegate_->material_data(p_id);
+    m.mat_data = scene_delegate_->material_data(p_id);
-  if (!mat_data_) {
+    if (!m.mat_data) {
-    scene_delegate_->materials_[p_id] = std::make_unique<MaterialData>(scene_delegate_, mat, p_id);
+      scene_delegate_->materials_[p_id] = std::make_unique<MaterialData>(scene_delegate_, mat, p_id);
-    mat_data_ = scene_delegate_->material_data(p_id);
+      m.mat_data = scene_delegate_->material_data(p_id);
-    mat_data_->init();
+      m.mat_data->init();
-    mat_data_->insert();
+      m.mat_data->insert();
-  }
-
-  if (mesh) {
-    face_material_indices_.clear();
-    const int *material_indices = BKE_mesh_material_indices(mesh);
-    const int *looptri_polys = BKE_mesh_runtime_looptri_polys_ensure(mesh);
-    int poly_ind;
-    blender::Span<MLoopTri> loopTris = mesh->looptris();
-    for (size_t i = 0; i < loopTris.size(); ++i) {
-      poly_ind = looptri_polys[i];
-      face_material_indices_.push_back(material_indices[poly_ind]);
     }
   }
 }

source/blender/render/hydra/scene_delegate/mesh.h

@@ -41,18 +41,15 @@ class MeshData : public ObjectData {
 
  private:
   void write_mesh(Mesh *mesh);
-  void write_material(Mesh *mesh);
+  void write_material();
   void write_uv_maps(Mesh *mesh);
   void write_normals(Mesh *mesh);
 
-  pxr::VtIntArray face_vertex_counts_;
-  pxr::VtIntArray face_vertex_indices_;
   pxr::VtVec3fArray vertices_;
   pxr::VtVec2fArray uvs_;
   pxr::VtVec3fArray normals_;
 
-  pxr::VtIntArray face_material_indices_;
+  std::vector<MaterialMesh> material_meshes_;
-  MaterialData *mat_data_ = nullptr;
 };
 
 }  // namespace blender::render::hydra