ChafaWorkCell: Linear scan for contrasting color pair#334
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hpjansson
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Jun 9, 2026
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Looks good, but the commit message should read ChafaWorkCell: ... instead of chafa: .... By convention the latter refers to the CLI tool code.
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Thanks a lot for these PRs and the quick edit! |
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chafa_work_cell_get_contrasting_color_pair previously relied on work_cell_get_dominant_channel, which performed a full counting sort over 4x64 RGBA values to determine the dominant channel and select the two extreme colors.
The result was used only for its min and max values. This change replaces the sort with a single linear scan that tracks min/max indices per channel directly.
The change is bit-identical on all test cases. It matches the old stable-sort tie-breaking behavior: the first occurrence wins for min, the last for max.
Performance
Linux x86_64, AMD Ryzen 9 7900X, GCC 15.2 -O2,
perf stat -r 3