Cycles: Added Cryptomatte output.

This allows for extra output passes that encode automatic object and material masks
for the entire scene. It is an implementation of the Cryptomatte standard as
introduced by Psyop. A good future extension would be to add a manifest to the
export and to do plenty of testing to ensure that it is fully compatible with other
renderers and compositing programs that use Cryptomatte.

Internally, it adds the ability for Cycles to have several passes of the same type
that are distinguished by their name.

Differential Revision: https://developer.blender.org/D3538

1 files changed, 17 insertions, 0 deletions

diff --git a/intern/cycles/blender/blender_object.cpp b/intern/cycles/blender/blender_object.cpp
index 0fab9ab3531..a05c982b367 100644
--- a/intern/cycles/blender/blender_object.cpp
+++ b/intern/cycles/blender/blender_object.cpp
@@ -384,6 +384,23 @@ Object *BlenderSync::sync_object(BL::Object& b_parent,
 		object_updated = true;
 	}
 
+	/* sync the asset name for Cryptomatte */
+	BL::Object parent = b_ob.parent();
+	ustring parent_name;
+	if(parent) {
+		while(parent.parent()) {
+			parent = parent.parent();
+		}
+		parent_name = parent.name();
+	}
+	else {
+		parent_name = b_ob.name();
+	}
+	if(object->asset_name != parent_name) {
+		object->asset_name = parent_name;
+		object_updated = true;
+	}
+
 	/* object sync
 	 * transform comparison should not be needed, but duplis don't work perfect
 	 * in the depsgraph and may not signal changes, so this is a workaround */