   depth sorting + texture/vertex/color arrays
  So I'm developing a 3D game for the iPhone, and it's a 3D game. I've been using texture/vertex/color arrays for their supposed increase in performance, as opposed to drawing each billboarded sprite by itself. Never had a chance to test the performance increase though..And then came the time when I needed to have them depth sorted. But then again, if sorted by depth, you can't really bunch the drawings together in an array, unless the arrays themselves are depth sorted, and everythign uses a single texture (maybe atlassed).So yeah, has anyone ever encountered this situation? I'm working through the depth sort algorithm right now, it's a bit tedious, and I have a feeling I'm not doing the right thing :(   
  Hmm, so dynamic VBOs..I actually managed to finish implementing the sorting system, and sorting around my texture/color/coord array was quite slow, will dynamic VBOs help this? Are dynamic VBOs sortable effectively? The slow bit was physically moving the array elements, since I put the indexes on a separate array to sort.Can dynamic VBOs do what I did faster? Seems like there's no functions in opengl ES that lets you swap around parts of a VBO (for sorting)..Then again right now I'm just limiting the amount of depth sorted sprites, probably a better solution.. the rest of the sprites will not have alpha, just blank pixels (removed by glAlphaFunc).   ;  You don't need depth sorting on IPhone hardware, it uses a different rendering method, than normal PC videocards, that makes depth sorting unnecessary.   ;  As far as I know you don't need dept sorting on pc hardware either, unless it is for transparent objects. I don't think that this is any different on the iPhone.Can you tell me what other rendering method is used on the iPhone, sirpalee?   ;  Oops, iPhone not PC!  Everything I mentioned was for the PC.There is an iPhone forum on here.  Your question might get overlooked here by PC users:http://www.gamedev.net/community/forums/forum.asp?forum_id=39[Edited by - theequal on May 30, 2009 5:09:41 PM];  Actually, it is for transparent (semi-transparent) objects.. they look odd without depth sorting.   