[Bf-blender-cvs] [178405ef174] temp-geometry-nodes-normal-attribute: Test derived normals write attribute

[Hans Goudey]

Commit: 178405ef1745782026c07e511a793cb5c8eb69f8
Author: Hans Goudey
Date:   Fri Jan 22 08:14:34 2021 -0600
Branches: temp-geometry-nodes-normal-attribute
https://developer.blender.org/rB178405ef1745782026c07e511a793cb5c8eb69f8

Test derived normals write attribute

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

M	source/blender/blenkernel/intern/attribute_access.cc

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

diff --git a/source/blender/blenkernel/intern/attribute_access.cc b/source/blender/blenkernel/intern/attribute_access.cc
index f65c39ca78b..15a64e247fa 100644
--- a/source/blender/blenkernel/intern/attribute_access.cc
+++ b/source/blender/blenkernel/intern/attribute_access.cc
@@ -1235,8 +1235,8 @@ ReadAttributePtr MeshComponent::attribute_try_get_for_read(const StringRef attri
     return polygon_attribute;
   }
 
-  /* Normals are also stored in MVert, so if no CD_NORMAL custom data layer
-   * was found, retrieve them from there. */
+  /* Normals are also stored in MVert, so if no CD_NORMAL
+   * custom data layer was found, retrieve them from there. */
   if (attribute_name == "normal") {
     auto get_vertex_normal = [](const MVert &vert) {
       float3 result;
@@ -1317,6 +1317,27 @@ WriteAttributePtr MeshComponent::attribute_try_get_for_write(const StringRef att
     return polygon_attribute;
   }
 
+  /* Normals are also stored in MVert, so if no CD_NORMAL
+   * custom data layer was found, retrieve them from there. */
+  if (attribute_name == "normal") {
+    auto get_vertex_normal = [](const MVert &vert) {
+      float3 result;
+      normal_short_to_float_v3(result, vert.no);
+      return result;
+    };
+    auto set_vertex_normal = [](MVert &vert, const float3 &no) {
+      normal_float_to_short_v3(vert.no, no.normalized());
+    };
+    return std::make_unique<blender::bke::DerivedArrayWriteAttribute<MVert,
+                                                                     float3,
+                                                                     decltype(get_vertex_normal),
+                                                                     decltype(set_vertex_normal)>>(
+        ATTR_DOMAIN_POINT,
+        blender::MutableSpan(mesh_->mvert, mesh_->totvert),
+        get_vertex_normal,
+        set_vertex_normal);
+  }
+
   return {};
 }