"Curtis L. Olson" <[EMAIL PROTECTED]> said: > Lee Elliott writes: > > I've noticed this effect too, on the 2d clouds. I think it's an ordering > > issue. When I use transparent objects/textures in a model I have to be > > careful of it's position in the object list - basically, every object that > > comes after a transparent object is invisible when viewed through the > > transparent object. With the 2d clouds it's as though they are coming after > > the prop disk, in the object order, and so are invisible when seen through > > it. > > I think we should be drawing the 3d model of the aircraft last, after > the sky, terrain, and clouds.
Actually the model objects are sorted so that the transparencies are last so that they are higher on the stack and get rendered *first*. Blending requires the foreground alpha object to be known first, which makes perfect sense if you think about it. Someone might want to research the archives, on previous discussion of what happens to the terrain and the model if you render the sky at a different point. Norm's idea may be the only solution that could eliminate the tradeoffs in the current approach. One possibility might be to somehow tag transparent model objects in xml (or ac3d object data) so that they can be moved after (or during) a load. Then you could put the clouds into the transparent scenegraph along with the transparent object parts, and everything else can go into the other scenegraph. This would also be helpful to modelers who can at times face complex difficulties with manually sorting objects. Yet another thing that suggests an writing ac3d loader customized for simgear. Best, Jim _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
