The span pixel function and the four-pixel bilinear sampler work in vector lanes, a channel per
vector, but took and returned the colors a pixel at a time, so every span was transposed twice on the
way. Now they take a channel at a time with a stride. The staged rows keep each chunk's colors that
way from the start (their stage walks a channel at a time anyway), and DrawRectangle builds them so.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>