Light effect

Hi all,
I have a 3d ring with a great diamond on its top.
How can I create some light effect for the diamond ? Can you provide some link to a website ?
Thanks in advance.

I am not sure if I understood what you want and I dont have a link handy but you may want to use to search for ‘3d billboard’


For a diamond, you should try environment mapping, both inside then outside environment mapping will give a pretty good reflection/refraction effect.


Draw the diamond last,
Apply an environment sphere map texture.
Turn texgen sphere map on.
Set the blend function to be GL_ONE, GL_ONE
Enable blending
Disable depth writes, keep depth testing on
Draw the diamond back faces on, front faces culled
Draw the diamond front faces on back faces culled

Now, this will look pretty darned good, and doesn’t actually need the back faces then the frontface pass, but you may want to experiment with different blend functions and alpha values and colors between the passes, and different environment maps representing refraction vs reflection images.

To get more advanced you could go on to try cube mapping instead of sphere mapping and even try chromatic aberrations with multipass, all a bit too advanced for your first attempt.

[This message has been edited by dorbie (edited 08-25-2003).]