XPresso (R8's node-based expression editor) can be a bit daunting at first glance. Bjorn, of MAXON Germany, has assembled a series of examples of common animation tasks that should help to ease the pain of understanding and utilizing this powerful feature.
XPresso's well worth putting the time and energy into learning...now, have at her!
This example features the Ray Collision node.
Click on play Quicktime movie
It works pretty simple. Working between two points in space and an object, the Ray Collision node calculates where a ray cast from Point one to Point two will hit the object the first time.
You can use this functionality to place an object on an uneven surface. The points are calculated from the object's X and Z position plus or minus a large offset (Delta). The surface will most likely be between those points.
For further explanation, you will find detailed remarks on how the expression works in the Xpresso editor in the project file above.
