Animated VGA Shapes - No Framebuffer

Hi folks,

I thought I'd share my third project with you all. I got sort of obsessed with the idea of driving the VGA protocol without any frame buffer memory backing the display (note 1) and I wanted to see how far I could get with such a design. I ended up with a cute little program that bounces a few geometric shapes around the screen and also does boundary and collision detection.

There's a YouTube video here (http://youtu.be/ltEPILMaUMk) and the source code is here: https://github.com/kosak/PapilioPro-AnimatedShapes

Feedback on the code is very welcome. I'm a newbie VHDL programmer and I find the language sort of frustrating so I sort of made up my own coding conventions and did some other hacks. I also agonized a lot about how modular such a design should be and how inter-module communication should work.

In the process I've also generated a bunch of VHDL questions which I hope to post somewhere, if y'all don't mind. The first is hopefully an easy one: I used the IP Core generator to get a 25.175MHz pixel clock and it crapped out a huge number of files into my ipcore_dir. I'm sure most of those do not need to be checked into source control. Can you tell me which ones are supposed to be checked in?

Thanks for looking at my demo!

(note 1) mostly because I'm intimidated by the SDRAM :-)