let layer,

  fogShader,

  fog,

  ireland,

  bird,

  currentShaderIndex = 0;

let customShaders = [];

// https://photokit.com/editor/

function preload() {

  customShaders.push(loadShader("default.vert", "threshold.frag"));

  ireland = loadImage("ireland.jpg");

}

​

function setup() {

  createCanvas(600, 600, WEBGL);

  layer = createFramebuffer();

  noStroke();

}

​

function draw() {

  // Draw a scene to a framebuffer

  layer.begin();

  clear();

  lights();

  scale(1, -1);

  image(ireland, -width / 2, -height / 2, width, height);

  layer.end();

​

  shader(customShaders[currentShaderIndex]);

  // Threshold

  customShaders[currentShaderIndex].setUniform("threshold", 0.5);

  // All

  customShaders[currentShaderIndex].setUniform("texture", layer.color);

​

  rect(0, 0, width, height);

  resetShader(); // Line added by Scudly (Thanks!) If you know why removing this line breaks it, please lmk

}

​