Jaguar text layer

I completed the Jaguar version of the text layer. I tied it into the object/sprite system. One of oddities that I found is that sprites drawn at 8 pixels high repeat the last row of data. If they are 9 pixels high they work perfectly. I think this is documented in the official documents. Outside of the Sega CD and Neo Geo CD, this has been the easist text layer to implement. And, the Sega CD and Neo Geo CD have hardware to support this.

FM Towns continued.

I've added a text layer to the FM Towns version. I also changed the rendering around a little to avoid bottle necks.

FM Towns fixes.

Thanks to the author of the UNZ emulator, I fixed the access to the video memory (VRAM).

I'm also implementing a double buffering system to remove the flicker that can be seen at the top of the screen, when a sprite is moving. This is only visible on the real hardware.

Accessing VRAM through selector $010C changes the layout of VRAM. It's used for 256 color mode. Selector $0104 is used for 32,000 or 4 bit color. Before fixing the selector, the code required a weird routine modification to work correctly. Everything it working nicely now.

Back to work!

I implemented the score display into the Sega CD and Neo Geo CD versions. The other versions will require a little more work, since they don't support a character map.