Hi all, I''ve looked around for sometime and studied bsp trees but i''d like to know about how to build a bsp tree (close to optimal tree). most of the tutorials and the articles discuss the rendering algorithm. what i need is description (and hopefully some pseudocode) as to how to build a close to optimal bsp tree that''d produce good results when used w/ any decent bsp rendering engine. i have another question: can AVL trees be used to build a close to optimal bsp tree, if not why ? is there an open source bsp compiler that people with less that people with less than professional coding experience would find possible to go understand. thanks pals, Evil Smile -- "because the knowledge is of less value than the power to gather and generate knowledge" -- Jacco Bikker (The Phantom)