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Avoid modulo in Polygon pixel test - #11623
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get_pixel did two modulo operations per edge for every pixel, only to wrap around on the last edge. The RP2040 has no divide instruction, so this was most of the drawing time.
dhalbert
enabled auto-merge
October 16, 2026 21:42
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Polygon did two % operations per edge for every pixel it drew. They were only needed to wrap around on the last edge. The RP2040 has no divide instruction, so these took most of the drawing time.
Time to refresh a star-shaped polygon:
The edges are visited in the same order as before, so the output is the same. Flash is 16–48 bytes smaller.
Tested on both boards.