Stunt Car Racer for SuperCPU

This project is the fruit of playing around in the evenings for a few weeks,
most of which was spent studying the code of SCR out of curiosity. At some
point I realised that the physics time step could be adjusted through a
single hook that handled the integration of every variable. I immediately
thought to myself that a proper SCPU adaptation with silky smooth animation
might be much easier than I previously assumed. I quickly found another
important physics hook that affected the forces generated by contact with the
road, and the rest was just fixing a bunch of minor issues over a few
additional evenings.

The original game steps the race clock by a fixed 0.14 seconds per update, so
I decided to divide the time step by 7 to get a solid 50 fps output with
equivalent timings. As a result, the game has basically the same speed as
usual during practice rounds (the original takes almost exactly 0.14 actual
seconds per update), but it plays slightly faster when racing against an
opponent (where average update times can go as high as 0.18s in the original,
especially right behind the opponent). Thanks to the extra computing time
left, I could also crank up the view distance as well as the LOD to burn the
remaining cycles.

I decided to provide an alternative "turbo" version as well, where the time
step is only divided by 5, for those who want a more thrilling experience.
The clock still follows the real time, so race times are going to be shorter
with this variant.

Due to the nature of the changes some of the mechanics cannot work exactly the
same way, so I made a best effort to match the original experience. Notably,
damage calculation can only be approximated, and may need further tweaking.

Disclaimer: I don't have real hardware, so I could only test in Vice.

Happy racing!

cobbpg, 2021