Method resize

src/image/p5.Image.js:724–801

* Resizes the image to a given width and height. * * The image's original aspect ratio can be kept by passing 0 for either * `width` or `height`. For example, calling `img.resize(50, 0)` on an image * that was 500 × 300 pixels will resize it to 50 × 30 pixels. * * @para

(width, height)

   * }
   */
  resize(width, height) {
    // Copy contents to a temporary canvas, resize the original
    // and then copy back.
    //
    // There is a faster approach that involves just one copy and swapping the
    // this.canvas reference. We could switch to that approach if (as i think
    // is the case) there an expectation that the user would not hold a
    // reference to the backing canvas of a p5.Image. But since we do not
    // enforce that at the moment, I am leaving in the slower, but safer
    // implementation.

    // auto-resize
    if (width === 0 && height === 0) {
      width = this.canvas.width;
      height = this.canvas.height;
    } else if (width === 0) {
      width = this.canvas.width * height / this.canvas.height;
    } else if (height === 0) {
      height = this.canvas.height * width / this.canvas.width;
    }

    width = Math.floor(width);
    height = Math.floor(height);

    const tempCanvas = document.createElement('canvas');
    tempCanvas.width = width;
    tempCanvas.height = height;

    if (this.gifProperties) {
      const props = this.gifProperties;
      //adapted from github.com/LinusU/resize-image-data
      const nearestNeighbor = (src, dst) => {
        let pos = 0;
        for (let y = 0; y < dst.height; y++) {
          for (let x = 0; x < dst.width; x++) {
            const srcX = Math.floor(x * src.width / dst.width);
            const srcY = Math.floor(y * src.height / dst.height);
            let srcPos = (srcY * src.width + srcX) * 4;
            dst.data[pos++] = src.data[srcPos++]; // R
            dst.data[pos++] = src.data[srcPos++]; // G
            dst.data[pos++] = src.data[srcPos++]; // B
            dst.data[pos++] = src.data[srcPos++]; // A
          }
        }
      };
      for (let i = 0; i < props.numFrames; i++) {
        const resizedImageData = this.drawingContext.createImageData(
          width,
          height
        );
        nearestNeighbor(props.frames[i].image, resizedImageData);
        props.frames[i].image = resizedImageData;
      }
    }

    tempCanvas.getContext('2d').drawImage(
      this.canvas,
      0, 0, this.canvas.width, this.canvas.height,