50 lines
1.2 KiB
JavaScript
50 lines
1.2 KiB
JavaScript
import { isNodePattern } from '@jimp/utils';
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/**
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* Creates a circle out of an image.
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* @param {function(Error, Jimp)} options (optional) radius, x, y
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* @param {function(Error, Jimp)} cb (optional) a callback for when complete
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* @returns {Jimp} this for chaining of methods
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*/
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export default () => ({
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circle(options = {}, cb) {
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if (typeof options === 'function') {
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cb = options;
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options = {};
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}
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const radius =
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options.radius ||
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(this.bitmap.width > this.bitmap.height
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? this.bitmap.height
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: this.bitmap.width) / 2;
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const center = {
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x: typeof options.x === 'number' ? options.x : this.bitmap.width / 2,
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y: typeof options.y === 'number' ? options.y : this.bitmap.height / 2
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};
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this.scanQuiet(0, 0, this.bitmap.width, this.bitmap.height, function(
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x,
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y,
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idx
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) {
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const curR = Math.sqrt(
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Math.pow(x - center.x, 2) + Math.pow(y - center.y, 2)
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);
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if (radius - curR <= 0.0) {
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this.bitmap.data[idx + 3] = 0;
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} else if (radius - curR < 1.0) {
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this.bitmap.data[idx + 3] = 255 * (radius - curR);
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}
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});
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if (isNodePattern(cb)) {
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cb.call(this, null, this);
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}
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return this;
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}
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});
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