Using a double-precision vector parameter in a post process material results in significant delays from the time the parameter is set to the time the material appearance is updated. This issue occurs both during editing and while playing. Is this normal for post process materials or how can it be overcome?
Video Details:
The video shows two similar materials that have the same logic but different material domains, namely the post process domain and the surface domain. Both materials add some color to a point if that point is inside a sphere whose center is specified by the Center vector parameter. In this video, green is set for the post process material (_PP), and red is set for the surface material (_SOL). Note that the green color is added to the different meshes, while the red is only added to the floor. In the post process material, the bDoublePrecisionCenter static switch parameter is added. If bDoublePrecisionCenter is true, then the post process material is compiled with the double-precision center, otherwise it is compiled with the single-precision center. The materials are added to the scene using two blueprint actors, namely _SOL for the surface material and _PP for the post process material. The _SOL and _PP blueprints inherit from the common ancestor in which the Center parameter of the corresponding dynamic material instance is set to the position of the actor itself.
If the center is specified by a single-precision vector parameter (bDoublePrecisionCenter is false), then the post process material behaves normally that is the position of the green spot is always coincides with the position of the corresponding actor, and the green spot moves in sync with the red spot. If the center is specified by a double-precision vector parameter (bDoublePrecisionCenter is true), then the position of the green spot may significantly differ from the correct one, which can be seen both during editing and while playing. After saving and reopening the level, the post process material takes the correct position, but during the game the green spot does not move in sync with the red spot.