Hi everyone,
I’ve designed a GUI using openGL which involves positioning a small sphere on the surface of a large sphere using mouse input. I’ve written the code so that a left mouse click will position the object on the ‘near’ side of the sphere - no problem there. And with a right mouse click it will position it on the ‘far’ side of the sphere - i.e. behind the sphere. But I still want to be able to see the small sphere when its behind, so I thought to use some transparency. I’ve used glColor4f to give the large sphere an alpha value of 0.5, while the small sphere has an alpha value of 1.0. But when I move the small behind the large, it still disappears! As far as I know I’ve activated all the necessary blend function, depth buffer, depth testing, etc. Can anyone think where I might be going wrong??? Or do I need to give more information?
Thanks,
James