Rendering would produce invalid results or crash if the Vector pass was active but motion blur was inactive. This caused the OptiX BVH to be built with motion (because objects reported motion available), but the pipeline to be built without motion support (since with disabled motion blur this is not in the list of requested features). The two are not compatible and therefore caused issues. This patch fixes that by not building the BVH with motion if motion blur is not active (which makes sense).
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D5968
0091b84df0