spritesheet-creator/dist/smart_crop.js

Spritesheet Creator

"use strict";

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

/**
 * crops the fully transparent pixels from all borders of the image
 * @param  {Jimp} options.image Jimp image
 * @return {Object} cropped.left, .right, .up, .down - amount of pixels cropped
 */
function smartCrop(_ref) {
  var image = _ref.image;
  var w = image.bitmap.width;
  var h = image.bitmap.height;
  var minPixelsPerSide = 1; // to avoid cropping completely the image, resulting in an invalid 0 sized image

  var leftPixelsToCrop = 0;
  var upPixelsToCrop = 0;
  var downPixelsToCrop = 0;
  var rightPixelsToCrop = 0; // up side

  var b = false;

  for (var y = 0; y < h - minPixelsPerSide; y++) {
    for (var x = 0; x < w; x++) {
      var colorXY = image.getPixelColor(x, y);
      var rgba = image.constructor.intToRGBA(colorXY);

      if (rgba.a > 0) {
        b = true;
        upPixelsToCrop = y;
        break;
      }
    }

    if (b) break;
  } // left side


  b = false;

  for (var _x = 0; _x < w - minPixelsPerSide; _x++) {
    for (var _y = upPixelsToCrop; _y < h; _y++) {
      var _colorXY = image.getPixelColor(_x, _y);

      var _rgba = image.constructor.intToRGBA(_colorXY);

      if (_rgba.a > 0) {
        b = true;
        leftPixelsToCrop = _x;
        break;
      }
    }

    if (b) break;
  } // down side


  b = false;

  for (var _y2 = h - 1; _y2 >= upPixelsToCrop + minPixelsPerSide; _y2--) {
    for (var _x2 = w - 1; _x2 >= leftPixelsToCrop; _x2--) {
      var _colorXY2 = image.getPixelColor(_x2, _y2);

      var _rgba2 = image.constructor.intToRGBA(_colorXY2);

      if (_rgba2.a > 0) {
        b = true;
        downPixelsToCrop = h - _y2 - 1;
        break;
      }
    }

    if (b) break;
  } // right side


  b = false;

  for (var _x3 = w - 1; _x3 >= 0 + leftPixelsToCrop + minPixelsPerSide; _x3--) {
    for (var _y3 = h - downPixelsToCrop; _y3 >= upPixelsToCrop; _y3--) {
      var _colorXY3 = image.getPixelColor(_x3, _y3);

      var _rgba3 = image.constructor.intToRGBA(_colorXY3);

      if (_rgba3.a > 0) {
        b = true;
        rightPixelsToCrop = w - _x3 - 1;
        break;
      }
    }

    if (b) break;
  }

  var widthOfRemainingPixels = w - (leftPixelsToCrop + rightPixelsToCrop);
  var heightOfRemainingPixels = h - (upPixelsToCrop + downPixelsToCrop); // do the real crop

  image.crop(leftPixelsToCrop, upPixelsToCrop, widthOfRemainingPixels, heightOfRemainingPixels);
  return {
    cropped: {
      up: upPixelsToCrop,
      down: downPixelsToCrop,
      right: rightPixelsToCrop,
      left: leftPixelsToCrop
    }
  };
}