The CameraMap Operator offers a powerful way to map particles and use mapping data in such a creative way you might have not thought of before!
Mapping coordinates are created in a similar way like you might already know it form the standard camera map modifier of 3ds Max.
There are many ways to use this operator to create particle effect, things like camera mapping thousands of little spheres to form an object and disintegrate it or rebuild it from a dust cloud. A camera mapped particle setup might be used to drive a fragmentation and so on ... just imagine what YOU can do.
Be aware that the particles MUST have a shape BEFORE applying the camera mapping, so use Camera Map in a dynset after Object2Particle or StdShape or GeomInstance, not before.
Also realize the Camera Map operator can be controlled with its "On" input to assign the mapping at a distinct point in time such as the particle's birth. If an additional UV channel is needed later this can be accomlpished by again controlling the "On" input and specifying a new UV channel integer (or of course it can overwrite the previous UV assignment).
One very powerful way to use this operator is to pick the main render camera and allow the CameraMap operator to activate every frame or sample. Then in a compositing program you can paint a mask on top of the rendered sequence and use that mask to activate certain particles or areas. For example during a shot driving through a collapsing canyon you can paint per frame which parts of the canyon will be activated (fragmented, etc). Be aware you may need to add additional controls such as distance checks to the camera to avoid affecting all particles in that line of depth (i.e. the ray created from the camera through the mask out to infinity).
