jsl-prism.PaintAlphaTextureLinearGradient.jsl Maven / Gradle / Ivy
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// texture containing gradient colors
param sampler colors;
// content.x = half pixel X offset
// content.y = Y coordinate of gradient row
// content.z = scale factor for fract
// content.w = scale factor for clamp
// scale factors for PAD = (0, 0.5)
// scale factors for REPEAT = (0.5, 0)
// scale factors for REFLECT = (1.0-halfpix, 0)
param float4 content;
float4 paint(float2 texCoord)
{
float2 fractvals = float2(fract(texCoord.x), clamp(texCoord.x, 0.0, 1.0));
float2 clrCoord = float2(content.x + dot(fractvals, content.zw), content.y);
return sample(colors, clrCoord);
}