Deterministic 256×1 RGBA colormap LUT for the colormap-parity cases.
A diagonal gradient (R ramps up, B ramps down, G a triangle) so the
sampled colour varies meaningfully with the lookup coordinate t —
making gamma-on-value warping observable. Matches the production
colormap texture layout/filtering (colormap-textures.ts) so both
backends sample it identically.
Deterministic 256×1 RGBA colormap LUT for the colormap-parity cases. A diagonal gradient (R ramps up, B ramps down, G a triangle) so the sampled colour varies meaningfully with the lookup coordinate
t— making gamma-on-value warping observable. Matches the production colormap texture layout/filtering (colormap-textures.ts) so both backends sample it identically.