Interactive Collision Detection for Molecular Graphics

Collision detection between hard-sphere representations of molecules can be performed in interactive times on existing graphics hardware. This thesis presents a system that allows a user to interactively move a small drug molecule near a larger receptor molecule and have the system immediately inform the user when a collision between the two molecules has occurred. The system uses a 3-D grid data structure to speed up the search for collisions. The collision detection and the generation of images of the molecules are performed by the Pixel-Planes 4 graphics engine. Preliminary trials of the system had users perform a simple geometric task, and the results indicate that stopping an object’s motion completely as the response to collisions is a hindrance to such tasks. This suggests that a better behavior for collision response must be found before collision response can aid in performing similar geometric tasks.