Jim Wilson writes: > Norman Vine <[EMAIL PROTECTED]> said: > > > Jim Wilson writes: > > > > > Then what does ssgTexTrans:: support? > > > > It controls the texture transform > > > > google( "glMatrixMode GL_TEXTURE" ) > > > > That's correct, but I haven't used that. My reading is you can apply matrices > to rotate and translate the texture mapping coordinates. For example if > square is mapped to 0.45 x 0.45, 0.45 x 0.55, 0.55 x 0.55, 0.55 x 0.45 on x/y > and you translate 0.1 on y, it'll "move" the texture down 0.1 so that the > mapping is now 0.45 x 0.55, 0.45 x 0.65, 0.55 x 0.65, 0.55 x 0.55. Or you you > rotate 90 degrees on the z axis it'll turn the texture on it's right side.
I think the answer is yes but I am not sure I follow exactly ... The glMatrixMode(GL_TEXTURE) transforms the coordinates within "texture space" ie in texture2D in the UV space of the bound texture just as the more usual matrix modes transform an objects geometrical position In the case of a 3D cockpit there may be a good use for this in building the texture up but the main problem I see is still going to be polygon offset related, so I am suggesting that a better approach might be to bind to textureObjects rather then an actual texture and then build the texture object each frame and use the subTexture call to update the textureObject This way there will be no polygon offset issues as there won't be multiply layerd instruments it will all be in a single texture bound to the face of the instrument A cheap trick but it is fast and sidesteps some thorns do a grep on "glMatrixMode(GL_TEXTURE)" in the glut source tree for lots of examples Norman _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
