1 files changed, 22 insertions, 0 deletions
diff --git a/intern/cycles/render/buffers.cpp b/intern/cycles/render/buffers.cpp
index bda20a8ab9d..a80851b945a 100644
--- a/intern/cycles/render/buffers.cpp
+++ b/intern/cycles/render/buffers.cpp
@@ -221,6 +221,28 @@ bool RenderBuffers::get_pass(PassType type, float exposure, int sample, int comp
 					pixels[3] = 1.0f;
 				}
 			}
+			else if(type == PASS_MOTION) {
+				/* need to normalize by number of samples accumulated for motion */
+				pass_offset = 0;
+				foreach(Pass& color_pass, params.passes) {
+					if(color_pass.type == PASS_MOTION_WEIGHT)
+						break;
+					pass_offset += color_pass.components;
+				}
+
+				float *in_weight = (float*)buffer.data_pointer + pass_offset;
+
+				for(int i = 0; i < size; i++, in += pass_stride, in_weight += pass_stride, pixels += 4) {
+					float4 f = make_float4(in[0], in[1], in[2], in[3]);
+					float w = in_weight[0];
+					float invw = (w > 0.0f)? 1.0f/w: 0.0f;
+
+					pixels[0] = f.x*invw;
+					pixels[1] = f.y*invw;
+					pixels[2] = f.z*invw;
+					pixels[3] = f.w*invw;
+				}
+			}
 			else {
 				for(int i = 0; i < size; i++, in += pass_stride, pixels += 4) {
 					float4 f = make_float4(in[0], in[1], in[2], in[3]);