index.js•1.25 kB
import { isNodePattern, throwError } from "@jimp/utils";
/**
* Flip the image horizontally
* @param {boolean} horizontal a Boolean, if true the image will be flipped horizontally
* @param {boolean} vertical a Boolean, if true the image will be flipped vertically
* @param {function(Error, Jimp)} cb (optional) a callback for when complete
* @returns {Jimp} this for chaining of methods
*/
function flipFn(horizontal, vertical, cb) {
if (typeof horizontal !== "boolean" || typeof vertical !== "boolean")
return throwError.call(
this,
"horizontal and vertical must be Booleans",
cb
);
const bitmap = Buffer.alloc(this.bitmap.data.length);
this.scanQuiet(
0,
0,
this.bitmap.width,
this.bitmap.height,
function (x, y, idx) {
const _x = horizontal ? this.bitmap.width - 1 - x : x;
const _y = vertical ? this.bitmap.height - 1 - y : y;
const _idx = (this.bitmap.width * _y + _x) << 2;
const data = this.bitmap.data.readUInt32BE(idx);
bitmap.writeUInt32BE(data, _idx);
}
);
this.bitmap.data = Buffer.from(bitmap);
if (isNodePattern(cb)) {
cb.call(this, null, this);
}
return this;
}
export default () => ({
flip: flipFn,
mirror: flipFn,
});