tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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utils.js (811B)

      1 export function multiplyAlpha(pixel) {
      2  return pixel.map((channel, i) => {
      3    // Pass the alpha channel through unchanged
      4    if (i === 3) return channel;
      5    // Otherwise, multiply by alpha
      6    return channel * pixel[3];
      7  });
      8 }
      9 
     10 export function unmultiplyAlpha(pixel) {
     11  return pixel.map((channel, i) => {
     12    // Pass the alpha channel through unchanged
     13    if (i === 3) return channel;
     14    // Avoid divide-by-zero
     15    if (pixel[3] === 0) return channel;
     16    // Divide by alpha
     17    return channel / pixel[3];
     18  });
     19 }
     20 
     21 export function clamp01(value) {
     22  if (value < 0) return 0;
     23  if (value > 1) return 1;
     24  return value;
     25 }
     26 
     27 const toPercent = (num) => `${num * 100}%`;
     28 export const toCSSColor = (pixel) =>
     29  `rgb(${toPercent(pixel[0])} ${toPercent(pixel[1])} ${toPercent(pixel[2])} / ${
     30    pixel[3]
     31  })`;