I am writing an image morphing program. I want to blend two images as textures of a grid with alpha channel. But i wonder how to implement this in openGL. Who can help please?
If you want to blend two images, use the blending functions of OpenGL:
glEnable(GL_BLEND);
glBlendFunc(…);
glBlendEquationEXT(…); requires loading an extension
glBlendFuncSeparateEXT(…); see above
glDisable(GL_BLEND);
if you need to do something more intricate than that, your best bet might be to use pixel shaders or something similar.