gouraud texturing

I am not really sure what the technical description of my problem is, but the title pretty much describes it. I would like to have it so that on a polygon there is a smooth transition from one texture to another between vertices (or, from two different alpha texture values, to two other alpha texture values). I am pretty sure I could do this with multiple passes, but I was wondering if there is any way to do this with multi-texuring.

Thanks for any help,


Should be possible with GL_ARB_texture_env_combine (or GL_EXT_texture_env_combine). Use the GL_INTERPOLATE_ARB combine function.