Moved the GPU function gpu_bmesh_face_visible() to BKE_paint and inverted the test to match equivalent tests for other mesh types: paint_is_bmesh_face_hidden(). Changed BKE_pbvh_bmesh_node_save_orig() to not save hidden faces into the triangle array. Modified the non-use-original branch of pbvh_bmesh_node_raycast() to skip hidden faces. Fixes bug #33914: projects.blender.org/tracker/index.php?func=detail&aid=33914&group_id=9&atid=498