Rendering Freestyle strokes behind objects using alpha transparency Is there any way to render Freestyle edges according to their real visibility on camera, by taking in consideration the alpha transparency maps of occluding objects, without compositing multiple render layers ?

There is scenarios where compositing RenderLayers cannot be done, because the occluding object surrounds the target (ex. particle field) or because of the scene complexity (too much objects, camera paths...).

In the following example, green strokes aren't rendered when occluded by the plane with a red overlay that uses Z transparency and a circle texture as alpha.
This is not possible in the current implementation of Freestyle.

Blender 2.79, Freestyle Known Limitations


  Transparent faces are treated as opaque faces.


@gandalf3 / Blender 2.6