Embodiments of the invention set forth a technique for animating objects placed across a surface of a graphics object. A CAD application receives a set of motions and initially applies a different motion in the set of motions to each object placed across the surface of the graphics object. The CAD application calculates bounding areas of each object according to the current motion applied thereto, which are subsequently used by the CAD application to identify collisions that are occurring or will occur between the objects. Identified collisions are cured by identifying valid motions in the set of motions that can be applied to a colliding object and then calculating bounding areas for the valid motions to select a valid motion that, when applied to the object, does not cause the object to collide with any other objects.