Sorting Transparency

So this is the classic problem where you have perpendical quads and neither are in front or behind the other. Well i think the only easy solution here would be to dided the quads in half vertically at the intersection line so you have 4 quads. Then render these back to front.

Are you actually having problems with the sorting and vertex buffer manipulation or just this particular problem?

ace

I'm not really having problems yet. I currently just sort entire models for transparency. But trees are high on my todo list, and I'm trying to figure out what exactly I'll be falling into.

I don't like the idea of messing with vertex buffers, though. Is that what they're doing? Wouldn't it be better in this case to simply build that tree section with four polygons instead? And if you're going to build with four polygons, why make them look like two intersecting polygons instead of making the tree look more natural?

Are you sure that's what they're doing?

edit: Forgot to say thanks :)

Well 4 polygons is very easy to sort and looks reasonably good as well as being cheap. If you create your vertex buffer with Dynamic usage then writing to it isnt so expensive.

I would suggest that in that picture they are using 4 polygons and sorting them as i said before. I have an example of a cube i rendered transparent with something inside of it, if you are interested you can have the code, might be a reasonable working example.


ace