index.js•1.28 kB
import { isNodePattern } from "@jimp/utils";
/**
* Creates a circle out of an image.
* @param {function(Error, Jimp)} options (optional) radius, x, y
* @param {function(Error, Jimp)} cb (optional) a callback for when complete
* @returns {Jimp} this for chaining of methods
*/
export default () => ({
circle(options = {}, cb) {
if (typeof options === "function") {
cb = options;
options = {};
}
const radius =
options.radius ||
(this.bitmap.width > this.bitmap.height
? this.bitmap.height
: this.bitmap.width) / 2;
const center = {
x: typeof options.x === "number" ? options.x : this.bitmap.width / 2,
y: typeof options.y === "number" ? options.y : this.bitmap.height / 2,
};
this.scanQuiet(
0,
0,
this.bitmap.width,
this.bitmap.height,
function (x, y, idx) {
const curR = Math.sqrt(
Math.pow(x - center.x, 2) + Math.pow(y - center.y, 2)
);
if (radius - curR <= 0.0) {
this.bitmap.data[idx + 3] = 0;
} else if (radius - curR < 1.0) {
this.bitmap.data[idx + 3] = 255 * (radius - curR);
}
}
);
if (isNodePattern(cb)) {
cb.call(this, null, this);
}
return this;
},
});