Sometimes it is necessary to sample a 3D texture at a certain position in space, and you can do a lot of neat effects like drive shader attributes, particle attributes, control crowd behaviours, object placement, etc. Unfortunately this feature doesn’t exist out of the box inside Maya, which is why I wrote the Sample Texture Command plugin to do this. Its written in C++ and works very fast for large nubmers of sample queries. Can sample both 2d or 3d textures.
In this example I drive the particle color and scale based on the 3d texture and their position inside it. You could do anything you want with the data though.