Shading: Add Vertex Color node.

This patch adds a new Vertex Color node. The node also returns the alpha
of the vertex color layer as an output.

Reviewers: brecht

Differential Revision: https://developer.blender.org/D5767

2 files changed, 41 insertions, 0 deletions

diff --git a/intern/cycles/kernel/shaders/CMakeLists.txt b/intern/cycles/kernel/shaders/CMakeLists.txt
index 38ba113a184..f4258da70d3 100644
--- a/intern/cycles/kernel/shaders/CMakeLists.txt
+++ b/intern/cycles/kernel/shaders/CMakeLists.txt
@@ -80,6 +80,7 @@ set(SRC_OSL
   node_vector_math.osl
   node_vector_transform.osl
   node_velvet_bsdf.osl
+  node_vertex_color.osl
   node_voronoi_texture.osl
   node_voxel_texture.osl
   node_wavelength.osl
diff --git a/intern/cycles/kernel/shaders/node_vertex_color.osl b/intern/cycles/kernel/shaders/node_vertex_color.osl
new file mode 100644
index 00000000000..1997a690181
--- /dev/null
+++ b/intern/cycles/kernel/shaders/node_vertex_color.osl
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2011-2013 Blender Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "stdosl.h"
+
+shader node_vertex_color(string bump_offset = "center",
+                         string layer_name = "",
+                         output color Color = 0.0,
+                         output float Alpha = 0.0)
+{
+  float vertex_color[4];
+  if (getattribute(layer_name, vertex_color)) {
+    Color = color(vertex_color[0], vertex_color[1], vertex_color[2]);
+    Alpha = vertex_color[3];
+
+    if (bump_offset == "dx") {
+      Color += Dx(Color);
+      Alpha += Dx(Alpha);
+    }
+    else if (bump_offset == "dy") {
+      Color += Dy(Color);
+      Alpha += Dy(Alpha);
+    }
+  } else {
+    warning("%s", "Invalid attribute.");
+  }
+}