How do I set up a material with diffuse, normal and alpha (transparency) maps? I'm finding it very difficult to set up a basic material with diffuse, alpha and normal maps. Although I've managed to create a material with diffuse and normal maps, I can't manage to get the alpha channel working correctly. I would like to use three separate maps as shown below:







Below is the desired result of combining the maps with a single spotlight shining from above.



Although I found a few examples of setting up materials with transparency online, I couldn't get anything to work correctly. Instead of me posting lots of pictures of my failed setup, could someone explain the correct way to combine these maps? I would really like to see both how to do it in the standard material/texture panels, and also in the node editor. I would like the result to appear in the real-time textured viewport mode.

In order to help explain what I am trying to set up, here is a picture of the current result of the material as it looks with lighting in my scene. I'm viewing using GLSL, but if I switch to multitexture, it's entirely black. I tried rendering it, but I just get the result shown here.



UPDATE: Partial Answer

Thanks to this tutorial, I managed to achieve the result I want if I'm rendering in cycles. The problem with this is that I want a clean real-time render that works in the viewport, so I'm still only half-way to a real answer. Here's my node setup for cycles:



However, as I said, I would like to see this kind of bump mapping working with alpha in the standard real-time view:
The only problem I see in the node setup is that the normal map image texture should be put through a normal map node to convert the color output data of the image texture to the required normal input of the shader.