Optimize case 15 of marching squares - #8054
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StephenCWills merged 1 commit intoJul 3, 2025
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This PR optimizes the code for rendering a fully lit tile when using per-pixel lighting. Since we know that every pixel in the tile should be rendered, we can quickly draw the whole diamond using raw computations to determine how many pixels in each row should be drawn.
I'm targeting this case because the benchmark for
light_render.cppindicates that the vast majority of time is spent on case 15 of the marching squares algorithm. It makes sense because that case is used to fill the tiles in the center of every contour line so we should expect to encounter that case pretty often if there are any contour lines at all.