Alpha Mask / アルファマスク

画像の「マスク」を読み込んで、画像のさまざまな部分の透明度を指定します。2つの画像は、p5.Imageの mask() メソッドを使用してブレンドされます。

mask alpha
Image

View Source Code

/*
 * @name Alpha Mask
 * @arialabel An astronaut on a planet as the background with a slightly transparent version of this image on top that moves with the user’s mouse. Both have a light blue gradient on the right side.
 * @description Loads a "mask" for an image to specify the transparency in
 * different parts of the image. The two images are blended together using
 * the mask() method of p5.Image.
 * <p><em><span class="small"> To run this example locally, you will need two
 * image files, and a running <a href="https://github.com/processing/p5.js/wiki/Local-server">
 * local server</a>.</span></em></p>
 */
let img;
let imgMask;

function preload() {
  // img = loadImage('assets/moonwalk.jpg');
  img = loadImage('../../../../p5js-website-legacy-examples/assets/moonwalk.jpg');
  // imgMask = loadImage('assets/mask.png');
  imgMask = loadImage('../../../../p5js-website-legacy-examples/assets/mask.png');
}

function setup() {
  // createCanvas(720, 400);
  createCanvas(windowWidth, windowHeight);
  img.mask(imgMask);
  imageMode(CENTER);
}

function draw() {
  background(0, 102, 153);
  image(img, width / 2, height / 2);
  image(img, mouseX, mouseY);
}

License

Source code is available on GitHub p5.js website legacy.

All examples are licensed under CC BY-NC-SA 4.0.