I want to map 2 textures simultaniously on a plane, by use of autom texture coord gen, and apply a function, written in cg, while rendering these textures. It seems that only texture buffer GL_TEXTURE0 is able to render with the autom texture gen; if I specify another texture buffer, then no texture is rendered. So I can only render the textures one after the other, and seem not to be able to apply the cg function on them without rerendering both results of the framebuffer with specifying glMultiTexCoord2f.
Is there a way to apply a cg function on 2 textures without rendering them with glMultiTexCoord2f, but with use of autom texture generation? How can I get autom texture generation work with other texture buffers as GL_TEXTURE0