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redblobgames/remove-alpha-on-canvas.js

Created September 19, 2018 20:41
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Remove alpha channel on a canvas, so it's always transparent or always opaque
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remove-alpha-on-canvas.js
const imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);
const pixels = imageData.data;
for (let i = 3, n = canvas.width * canvas.height * 4; i < n; i += 4) {
pixels[i] = pixels[i] < 127? 0 : 255
}
ctx.putImageData(imageData, 0, 0);
@pmallol
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pmallol commented Feb 18, 2022

Thank you! 🔥

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