Me and a colleage are using c++ and opengl (compatibility profile for learning purposes) at my university and we implemented phong shading for point lights. Now we should program a little game, so we decided to create a simple space invaders clone.
For a start, we simply put a few GL_TRIANLE pyramid objects with a texture on the screen and everything looks fine, but if we activate the phong shading, suddenly the textures all turn grey and we can't find out why? There is one point light in the middle of the screen and the phong shading was implemented for point lights.
Interesting fact: if we import a 3ds model in there, the shading works normal, it just won't work on the openGL created primitves?!
(Btw: we are using a custom (Visual Studio 2013 Ultimate) project framework with GLUT, GLee and more libraries already built in.)
Here are some pictures of what i mean:
We are still openGL beginners, so be gentle with us, thank you!