0070-2023-04-30.md

30 Apr 2023

Previous journal:	Next journal:
0069-2023-04-29.md	0071-2023-05-01.md

Raybox

• Started q16d16 branch for trying out Q16.16 fixed-point.
• Consider how this design, as a chip, should be controlled by a CPU. These parts would probably be part of the CPU, but could be optionally augmented by the chip too (esp. where there are common resources):
  • Motion
  • Collisions/deflections
  • Actual position/directional vectors
  • Sound
  • Map data
• Consider how to render other overlays or interstitials, inc. rectangles, triangles, bitmaps, text.
• Keep an eye out for specific instances where we can use/mix different fixed-point precisions and bit depths/balances. For instance, we know the heightScaler shouldn't ever get to (say) 32.0, and it really only needs 8 bits of fractional precision (for now)?

Notes

• VGA DAC
• Try build with Caravel
• Ask group the best way to do ring memory for Raybox:
  • 8~10 bits for height (height of 1024 is 425% scaling)
  • 1 bit for side
  • Optionally 1~4 bits for texture.
  • Min: 640x9 bits = 5760
  • Max: 640x15 bits= 9600
  • All groups of 9~15 bits can shift forward from a common clock
  • Better to use a simple Verilog array/chain/generator, or a macro generated by something?