i have been doing some research on bsp and octrees and have some questions: 1. which would be best for levels that alternate between indoor and outdoor areas? 2. which is better for collision detection? 3. which better suits conditions where characters (npc and player) and some objects may be moving in and out of nodes? 4. do display lists work for bsp or octrees? if so, would i just have to create a display list for each node? (on the topic of display lists -- can normal or paralax mapping be done with display lists or should i use vbos?) 5. does anyone have a good tutorial that discusses the theory and also has example code for your prefered method? 6. do these methods lend themselves to LOD algorithms? thanks for the help! disclaimer -- please do not tell me to download quake's source because i have, and following it is, to me, fairly difficult. also, i have read papers on the methods to do the partitioning, but i really don't know how to do it myself without seeing an example. i did search the forums but i am adverse to disecting someone's code that didn't specifically put it up as a tutorial or example.

no, more accurately i don't understand how you would divide polygons and i was never very good with linked lists. which is what octrees and bsp trees seem to be. furthermore, the papers and topics i have read seemed to say different things for instance -- it seems to me that most people use bsp trees for indoor environments and octrees for outdoor, but does one behave better than the other when used in both situations?

also, if the quake3 source is so easy to follow, where does one start in the quake3 source to understand how they build their bsp trees?

well, i'm just not very good at developing them myself. when i was working with them in class it made sense (and i have multiple data structure books i reference when working with linked lists and hashes and what not) but i'm not the greatest at sitting down and thinking them up right off the top of my head.

anyways, i guess this is a good time for an update --

i found a tutorial that had a great explanation of what is going on and essentially answered my questions on how to do it, collision detection, and display lists. however, i'm still wondering about which is preferable for LOD and moving objects.

when looking at bsp i noticed that the papers were saying stuff like "now pick a polygon to use as the splitting plane" and i wasn't sure if they ment manually or what. i just remember in school when working with binary trees we worked with ways to make them and then resort them so that they were ballanced, and that just wasn't fun. is this something that many bsp implementations use?

while i was reading the demo/tutorial i mentioned in my previous post it occurred to me that searching a large octree probably wasn't the best way to actually render the scene. so i was thinking i would use it only for collision detection (know what node an object is in and then only check collisions in there, or surrounding nodes if it is that big) and then keep a single display list as the rendering method.

thanks for the input!

again, thanks for the input!

i'm afraid i might have downplayed my knowledge. linked lists just weren't my favorite part and so took a little more time to grasp. that isn't to say i never did, i just don't believe they are my strongest point. which is exactly why i was looking for a tutorial/demo that would go through and explain what was going on. :)

toxic -- do you have links to any papers or discussions that helped you get the portal system into your engine?

well right now i'm using a display list to draw about 13k triangles and on my geforce4 mx440 i'm getting an average of 85 fps while on newer hardware it is about 1k. i know this isn't very indicative because there currently isn't any collision detection, shaders, or such stuff but my initial interest in the octree/bsp tree was for collision detection.

thanks again!