Files
panopainter/data/shaders/include/blend-stroke.glsl

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501 B
GLSL

mediump float blend_stroke(mediump float base, mediump float stroke, int mode)
{
if (mode == 0) /* normal */ return (base + stroke) * 0.5;
else if (mode == 1) /* multiply */ return base * stroke;
else if (mode == 2) /* screen */ return 1.0-(1.0-base)*(1.0-stroke);
else if (mode == 3) /* color-dodge */ return base/(1.0-stroke);
else if (mode == 4) /* overlay */ return mix(2.0*base*stroke, 1.0-2.0*(1.0-base)*(1.0-stroke), floor(base*2.0));
else return 1.0;
}