Optical Flow

2D Modifier - Use image feedback to convert movement to rgb colors

Use a frame delay to color the difference and so generate some kind of real time vector map. Better to put the iteration parameter to its maximum for a better effect. Very effective as a vector field map inside a Normal Map Layer set over a particle system.

Here is an example:

Variables:

Num Iterations: Number of iterations from detailled to broad (the more the better your normals will display big movements)
Rasterize Quality: Rasterize quality of the optical flow

Python

    Oil.createObject("OpticalFlowTextureModifier")