Template:Shade/bgcolor

rgb(({{{r}}}*{{{a}}}+{{{r_bg}}}*(1-{{{a}}})),({{{g}}}*{{{a}}}+{{{g_bg}}}*(1-{{{a}}})),({{{b}}}*{{{a}}}+{{{b_bg}}}*(1-{{{a}}})))

50px Template documentation

Calculates an rgba naively blended over a (by default) white background, i.e.

$C_{o}=C_{a}\alpha +C_{bg}(1-\alpha )$

The visual properties of a naive (nonlinear) sRGB blend is that color blending with greyscales mostly "work" visually.

{{Shade/bgcolor
|r    = <!-- red color component: 0-255 -->
|g    = <!-- green color component: 0-255 -->
|b    = <!-- blue color component: 0-255 -->
|a    = <!-- color transparency factor: 0.0-1.0 -->
|r_bg = <!-- red background color component: 0-255 (default=255) -->
|g_bg = <!-- green background color component: 0-255 (default=255) -->
|b_bg = <!-- blue background color component: 0-255 (default=255) -->
}}

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