Quake acetate

Similar to AcetateBlurField and AcetateHeatMirage: show a pixel from an underlying Acetate; exactly the pixel that it should be when the intensity is zero (or below a minimum threshold), or a random pixel around if the intensity is not zero. The texel to be fetched will have a displacement of the intensity multiplied by a random number.

Needs a random texture (like e.g. ditherify), needs redrawing at every frame.

The effect should be that of shaking/quake.