OCCL

Introduction

Occlusion is a feature in Vice City and San Andreas that helps make the game run smoother in certain parts of the game. Occlusion boxes disable models that are behind the box from rendering. The occlusions are controlled by the occlu.ipl file in Vice City and other files scattered around in San Andreas. Rockstar didn't use this feature efficiently and didn't improve this much from Vice City. Deleting all entries in the occlu section doesn't have a major affect on your games.

Details

Format of the occlu section of the IPL file:

direct mid x, direct mid y, bottom height z, width x, width y, height from bottom height to top,
rotation

• direct mid x, direct mid y: The middle of the occlusion box in X and Y coordinates.
  
• bottom height z: The bottom Z coordinate of the occlusion box.
  
• width x, width y: The width of the occlusion box in units of X and Y.
  
• height from bottom height to top: The difference in height from the top of the occlusion box to the bottom.
  
• rotation: The rotation of the occlusion box in angles (probably radians, I'm not sure).
  

Occlusion boxes can only be viewed through Moo Mapper v0.95 or higher.

References

Occlusion Tool (temp site)