index.js 4.61 KB
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports["default"] = void 0;

var _utils = require("@jimp/utils");

/**
 * Rotates an image clockwise by an arbitrary number of degrees. NB: 'this' must be a Jimp object.
 * @param {number} deg the number of degrees to rotate the image by
 * @param {string|boolean} mode (optional) resize mode or a boolean, if false then the width and height of the image will not be changed
 */
function advancedRotate(deg, mode) {
  deg %= 360;
  var rad = deg * Math.PI / 180;
  var cosine = Math.cos(rad);
  var sine = Math.sin(rad); // the final width and height will change if resize == true

  var w = this.bitmap.width;
  var h = this.bitmap.height;

  if (mode === true || typeof mode === 'string') {
    // resize the image to it maximum dimension and blit the existing image
    // onto the center so that when it is rotated the image is kept in bounds
    // http://stackoverflow.com/questions/3231176/how-to-get-size-of-a-rotated-rectangle
    // Plus 1 border pixel to ensure to show all rotated result for some cases.
    w = Math.ceil(Math.abs(this.bitmap.width * cosine) + Math.abs(this.bitmap.height * sine)) + 1;
    h = Math.ceil(Math.abs(this.bitmap.width * sine) + Math.abs(this.bitmap.height * cosine)) + 1; // Ensure destination to have even size to a better result.

    if (w % 2 !== 0) {
      w++;
    }

    if (h % 2 !== 0) {
      h++;
    }

    var c = this.cloneQuiet();
    this.scanQuiet(0, 0, this.bitmap.width, this.bitmap.height, function (x, y, idx) {
      this.bitmap.data.writeUInt32BE(this._background, idx);
    });
    var max = Math.max(w, h, this.bitmap.width, this.bitmap.height);
    this.resize(max, max, mode);
    this.blit(c, this.bitmap.width / 2 - c.bitmap.width / 2, this.bitmap.height / 2 - c.bitmap.height / 2);
  }

  var bW = this.bitmap.width;
  var bH = this.bitmap.height;
  var dstBuffer = Buffer.alloc(this.bitmap.data.length);

  function createTranslationFunction(deltaX, deltaY) {
    return function (x, y) {
      return {
        x: x + deltaX,
        y: y + deltaY
      };
    };
  }

  var translate2Cartesian = createTranslationFunction(-(bW / 2), -(bH / 2));
  var translate2Screen = createTranslationFunction(bW / 2 + 0.5, bH / 2 + 0.5);

  for (var y = 1; y <= bH; y++) {
    for (var x = 1; x <= bW; x++) {
      var cartesian = translate2Cartesian(x, y);
      var source = translate2Screen(cosine * cartesian.x - sine * cartesian.y, cosine * cartesian.y + sine * cartesian.x);
      var dstIdx = bW * (y - 1) + x - 1 << 2;

      if (source.x >= 0 && source.x < bW && source.y >= 0 && source.y < bH) {
        var srcIdx = (bW * (source.y | 0) + source.x | 0) << 2;
        var pixelRGBA = this.bitmap.data.readUInt32BE(srcIdx);
        dstBuffer.writeUInt32BE(pixelRGBA, dstIdx);
      } else {
        // reset off-image pixels
        dstBuffer.writeUInt32BE(this._background, dstIdx);
      }
    }
  }

  this.bitmap.data = dstBuffer;

  if (mode === true || typeof mode === 'string') {
    // now crop the image to the final size
    var _x = bW / 2 - w / 2;

    var _y = bH / 2 - h / 2;

    this.crop(_x, _y, w, h);
  }
}

var _default = function _default() {
  return {
    /**
     * Rotates the image clockwise by a number of degrees. By default the width and height of the image will be resized appropriately.
     * @param {number} deg the number of degrees to rotate the image by
     * @param {string|boolean} mode (optional) resize mode or a boolean, if false then the width and height of the image will not be changed
     * @param {function(Error, Jimp)} cb (optional) a callback for when complete
     * @returns {Jimp} this for chaining of methods
     */
    rotate: function rotate(deg, mode, cb) {
      // enable overloading
      if (typeof mode === 'undefined' || mode === null) {
        // e.g. image.resize(120);
        // e.g. image.resize(120, null, cb);
        // e.g. image.resize(120, undefined, cb);
        mode = true;
      }

      if (typeof mode === 'function' && typeof cb === 'undefined') {
        // e.g. image.resize(120, cb);
        cb = mode;
        mode = true;
      }

      if (typeof deg !== 'number') {
        return _utils.throwError.call(this, 'deg must be a number', cb);
      }

      if (typeof mode !== 'boolean' && typeof mode !== 'string') {
        return _utils.throwError.call(this, 'mode must be a boolean or a string', cb);
      }

      advancedRotate.call(this, deg, mode, cb);

      if ((0, _utils.isNodePattern)(cb)) {
        cb.call(this, null, this);
      }

      return this;
    }
  };
};

exports["default"] = _default;
module.exports = exports.default;
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