Optimize draw_pixels with consecutive pixel caching#46
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Add per-instance cache for raw pixel values and pre-computed bit patterns. For consecutive identical pixels, skips: - extract_rgb888_from_format() call - 3 LUT lookups - bit_depth × pattern computation iterations Implementation: - Pack raw source bytes into uint32_t for single-comparison cache check - Cache pre-computed upper/lower patterns for all bit planes - Class members persist across draw_pixels() calls (benefits single-pixel APIs) Works on top of existing optimizations (identity fast path, branchless bit extraction, pointer arithmetic).
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When consecutive pixels have the same RGB values, skip redundant LUT
lookups and bit pattern computation by caching the pre-computed upper
and lower patterns. This avoids 3 LUT lookups and bit_depth×6 conditional
branches per duplicate pixel.
Particularly beneficial for images with solid color regions, UI elements
with flat backgrounds, and anti-aliased text with identical background pixels.