Cycles: Expose diffuse and glossy depth to Light Path node

Was a bit confusing to have transparent and translucent depth
exposed but no diffuse or glossy.

Reviewers: brecht

Subscribers: eyecandy

Differential Revision: https://developer.blender.org/D2399

intern/cycles/kernel/shaders/node_light_path.osl

@@ -27,6 +27,8 @@ shader node_light_path(
 	output float IsVolumeScatterRay = 0.0,
 	output float RayLength = 0.0,
 	output float RayDepth = 0.0,
+	output float DiffuseDepth = 0.0,
+	output float GlossyDepth = 0.0,
 	output float TransparentDepth = 0.0,
 	output float TransmissionDepth = 0.0)
 {
@@ -45,6 +47,14 @@ shader node_light_path(
 	getattribute("path:ray_depth", ray_depth);
 	RayDepth = (float)ray_depth;
 
+	int diffuse_depth;
+	getattribute("path:diffuse_depth", diffuse_depth);
+	DiffuseDepth = (float)diffuse_depth;
+
+	int glossy_depth;
+	getattribute("path:glossy_depth", glossy_depth);
+	GlossyDepth = (float)glossy_depth;
+
 	int transparent_depth;
 	getattribute("path:transparent_depth", transparent_depth);
 	TransparentDepth = (float)transparent_depth;