I wrote a ray tracer in Brainfuck

Automated excerpt

Two important primitives were move and copy. [a, 0] Move works by continually lowering a value until the cell at the initial data pointer becomes zero, and incrementing the other cell equally every time. [ # start loop And now, if needed, the terminal a can be moved inward. Given that addition, and later division, would involve repeated use of temporary values, which have to be near the value to avoid moving the data pointer around too much, every value in the map also has its temporary-variable slots nearby. Every iteration of the inner loop increments the result once.

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