Hello,
first of all, thanks for the answers you gave me before, it was very useful. But I have a new problem right with the performances of my application now, and I don't think it comes from the application itself. Let me explain.
I'm currently finishing a project using OpenSG and VRjuggler, and it's supposed to run into a virtual reality environment (a CAVE) within 4 days... It's a kind of game with some spaceships flying everywhere and shooting at you. We use some vrml files for the spaceships and all the objects. Everything worked fine with our tests until the day we introduced some home-made vrml models, which use textures. Before, the only object which used textures was the decor and it also worked fine. But now, we want to use textures with spaceships, which can be very numerous (almost 20 spaceships) in our scene, compared to the decor. The problem is that as soon as we did this, the performance dramatically decreased in the CAVE. The CAVE uses a cluster of 5 machines with GeForce Quadro graphic card so this should be largely sufficient to render 20 objects composed of 400 polygons
and 2 or 3 MB of tga and png textures. And also, when we make the application run in simulation mode, on a single PC, the frame rate is perfect. So we deleted the textures of the spaceship model and everything worked fine in the CAVE then...
So we would like to know where this problem can come from and we would like to know what does the simple vrml loader do when we load a model : are some OpenGL display lists created?
In fact, all our spaceships use the same model : the model is loaded separately first, and not inserted in the graph, and then, when a spaceship is added to the scene, we call a shallowCopy on the model node (in fact we call the shallowCopy on the model node and all its children nodes) and we add the new node to the graph. Is this a good way to make all the objects share the same model?
And have you ever heard about performance issues specefically in an environment like a CAVE or some compatibility problems with VRjuggler?
Sorry for this long message but we are a little overstressed with this problem as the deadline approaches...
Thanks for all
Jo
