hello, I''m little troubled with display list and hope you can help me. when, for example I want to put alot of buildings (3d models) in the scene - is there something bad in using display list. I don''t need any movement - just put them somewhere. you told me it''s not the fastest thing that exists - how is that? - as far as I know, it''s just load the 3d model into memory in the beginning of the program - and thats it, isn''t it? meaning that it doesn''t do anything which take time and resourses in the progress of the program - so how can it be slower from something else (maybe just in the beginning). am I worng with something? thanks.

Using display lists like you do is fine, using display lists you load the calls, like a model, into videocard memory and you can call the list to execute all calls in the list. You can't edit display lists so it's only an option for static models or something like a list of calls to set up lighting or any other series of calls you call multiple times and that don't change. The reason some other ways might be faster is that display lists usually take up a lot of memory (because they are compiled, they take up more space that way), with some extensions you place the data ordered in a much more efficient way, a disadvantage is that you can't use opengl calls but you simply load an array of vertices, texcoord and normal data.

[edited by - Tree Penguin on May 16, 2004 9:10:40 AM]

thanks.

so I didn''t completely understand.

if I put buildings in display lists - the all program will be slower? or it''s true only if I put moving things in it.

Loading (to the videocard) and compiling (storing the data in de graphicscard's memory by the graphicscard) is very slow and the compiled list costs much memory, if you use many display lists make sure the memory doesn't get full, this will cause everything to run slower. The fragmenting of the memory might also slow down but i don't know how to prevent that and how common that is. Anyway when that's not the case, calling a display list is faster than transferring all data to the graphicscard so display lists will speed up your program.

[edited by - Tree Penguin on May 17, 2004 1:11:37 PM]