2.2.1. Delta field type
The delta field type parameter allows you to specify the type of delta field used by the visualization.
The delta field is basically a mapping from each source pixel on the screen to a destination pixel. Pixel shaders are used to iteratively apply this delta field using interpolation and some light dithering effects. This feature is purely for aesthetic purposes and has no effect on the audio.
Raster type effects are drawn into the delta field on each frame.