Yep, you read that correctly: the SNES, of all consoles, is now capable of ray tracing — sort of. Obviously, the SNES lacks any sort of dedicated RT hardware, so Carter was forced to get a bit crafty. He created an external piece of tech that he calls the SuperRT,” a dedicated chip that handles lightweight ray tracing operations.
To create this chip and enable it to work, Carter removed the casing from both the SNES itself (the device is “otherwise unmodified,” he says) and a game cartridge, giving him room to run cables freely. SuperRT was then built directly into a cartridge, to add processing power without needing to modify the structure of hardware of the SNES itself.
The full breakdown of how the SuperRT works is incredibly technical in nature, but if you feel equipped to dive in, Carter goes into great detail on his project right here.
However, in short, the SuperRT uses a field-programmable gate array chip, or an FPGA, to gather scene information during gameplay. That information is then used to calculate accurate RT effects, such as reflections and shadows. The final renders are fed to the display, without putting any extra strain on the SNES itself (from what we can tell).
You can see the tech in action through the two videos above — the results are pretty impressive, given the limitations of the SNES’ hardware, and it would be quite interesting to see whether or not it could be made to work with actual games.