Problem displaying font texture (SDL Xcode 4 project)

The b开发者_运维百科elow project of mine works fine with OpenGL on Windows and the Mac but will not work on the iPhone simulator or physical device.

The below link is to an Xcode 4 project containing the usual SDL examples plus an extra one called Rectangles2. I can't get my font characters to appear on the screen - I just keep getting a white rectangle.

Can somebody please have a look and tell me what is wrong with my project?

Please don't be critical of how its coded - I would just like to know what I'm missing to make it work.

Xcode Project

Thanks

I've just been told the problem was my parameter to the glTexImage2D function. The code I borrowed uses some literal values 3 and 4 whatever they are. Anyway, changing these to GL_RGBA has solved my problem.. so I'll have to go and read up on what this function actually does and how it works etc.