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export function multiplyAlpha(pixel) {
return pixel.map((channel, i) => {
// Pass the alpha channel through unchanged
if (i === 3) return channel;
// Otherwise, multiply by alpha
return channel * pixel[3];
});
}
export function unmultiplyAlpha(pixel) {
return pixel.map((channel, i) => {
// Pass the alpha channel through unchanged
if (i === 3) return channel;
// Avoid divide-by-zero
if (pixel[3] === 0) return channel;
// Divide by alpha
return channel / pixel[3];
});
}
export function clamp01(value) {
if (value < 0) return 0;
if (value > 1) return 1;
return value;
}
const toPercent = (num) => `${num * 100}%`;
export const toCSSColor = (pixel) =>
`rgb(${toPercent(pixel[0])} ${toPercent(pixel[1])} ${toPercent(pixel[2])} / ${
pixel[3]
})`;
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