Original Post
I have problems with point sprites. I've followed the sdk code and all worked fine, if you look at the point sprites alone. Because with the rest of the objects in ym engine, there is problem. Transperency seems to work in a strange way. Alpha states are set the same way that in the sdk code (D3DBLEND_ONE), and again it works alone. The problem is that it screws up when crossing with textured polygons with colorkey alpha. The "invisible" square of those transparent polygons get over the point sprite and erase it. It is hard to explain. To make it brief, i see a colored particle with a big transparent square in the middle. It seems to have a certain link with zwrite (in the code it is desactivated to avoid certain problems). I put the point sprites rendering after all other rendering, to make it works. But it does what i stated before. The problem is solved by rendering them before the textured polygons, but then the point sprites are always behind those polygons, wich is not always wanted. Ive put a screen shot to clarify it : http://killergl.pingouin.ca/psprite.JPG As you see, the crosshair in the middle is a textured polygon with colorkey alpha. The blue thing is a point sprite. And as i said the transparency does a strange thing and so we can see trough the point sprite at the grass texture. All this long text to say this : I do not necessarky want to solve this particular problem. What i would like is a clear tutorial (or commented code, or even not commented) to implement point sprite in a complete engine. Not just showing particles alone on a dark background. You understand ? Thanks.