three-sketch

Events and Overwriting Event Handlers

The sketch emits update, resize, and mousemove events at the times you would expect. Most of the time, the default render/resize/mousemove event handlers will do everything you need. If you need to do something in addition, you can use the events to create side effects. If you need to do something completely different, you can overwrite some of the key handlers:

 
sketch.on('update', delta => {
  
  camera.rotation.y = sketch.time * 0.0001 % 360;
  
});
 
sketch.render = function (delta) {
  
  // The default render loop doesn't render to a texture. But now it will!
  sketch.renderer.render(sketch.scene, sketch.camera, someRenderTarget);
  
}

Example

import { Sketch } from '../src';
import { BoxBufferGeometry, MeshBasicMaterial, Mesh } from 'three';
 
window.onload = function () {
 
  const sketch = Sketch();
  
  document.body.appendChild(sketch.canvas);
 
  const geo = new BoxBufferGeometry(1, 1, 1);
  const mat = new MeshBasicMaterial({ color: 0xff0000 });
  const box = new Mesh(geo, mat);
 
  sketch.scene.add(box);
 
  sketch.camera.fov = 60;
  sketch.camera.position.z = 5;
  sketch.camera.updateProjectionMatrix();
  
  sketch.on('update', delta => {
    
    box.rotation.x = sketch.time * 0.0001 % 360;
    box.rotation.y = sketch.time * 0.0002 % 360;
    
  });
  
  sketch.on('resize', size => {
    
    // three-sketch takes care of everything
    
  });
 
  sketch.on('mousemove', mouse => {
    
    // mouse coorodinates are in range [-1, 1]
    sketch.camera.position.x = mouse.x;
    sketch.camera.position.y = mouse.y;
    sketch.camera.lookAt(box.position);
    
  });
  
  sketch.start();
 
};