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@valex
Created September 25, 2018 18:43
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Canvas as a bump map
<!DOCTYPE html>
<html>
<head>
<title>Example 10.10 - Canvas texture bumpmap</title>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/three.js/96/three.min.js"></script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/stats.js/r16/Stats.min.js"></script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.7.2/dat.gui.min.js"></script>
<script type="text/javascript" src="../libs96/perlin.js"></script>
<style>
body {
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin: 0;
overflow: hidden;
}
</style>
</head>
<body>
<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="canvas-output" style="float:left">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>
<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">
var canvas = document.createElement("canvas");
canvas.setAttribute("width", 256);
canvas.setAttribute("height", 256);
canvas.setAttribute("style", "position: absolute; x:0; y:0; bottom: 0px");
document.getElementById('canvas-output').appendChild(canvas);
var ctx = canvas.getContext("2d");
var date = new Date();
var pn = new Perlin('rnd' + date.getTime());
fillWithPerlin(pn, ctx);
function fillWithPerlin(perlin, ctx) {
for (var x = 0; x < 512; x++) {
for (var y = 0; y < 512; y++) {
var base = new THREE.Color(0xffffff);
var value = perlin.noise(x / 10, y / 10, 0);
base.multiplyScalar(value);
ctx.fillStyle = "#" + base.getHexString();
ctx.fillRect(x, y, 1, 1);
}
}
}
// once everything is loaded, we run our Three.js stuff.
function init() {
var stats = initStats();
// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();
// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(new THREE.Color(0xEEEEEE));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMap.enabled = true;
webGLRenderer.shadowMap.type = THREE.PCFSoftShadowMap; // default THREE.PCFShadowMap
var cube = createMesh(new THREE.BoxGeometry(12, 12, 12), "floor-wood.jpg");
cube.position.x = 3;
scene.add(cube);
// position and point the camera to the center of the scene
camera.position.x = 0;
camera.position.y = 12;
camera.position.z = 28;
camera.lookAt(new THREE.Vector3(0, 0, 0));
var ambiLight = new THREE.AmbientLight(0x141414);
scene.add(ambiLight);
var light = new THREE.DirectionalLight();
light.position.set(0, 30, 20);
scene.add(light);
// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);
// call the render function
var step = 0;
// var polyhedron = createMesh(new THREE.PolyhedronGeometry(vertices, faces, controls.radius, controls.detail));
// setup the control gui
var controls = new function () {
this.bumpScale = cube.material.bumpScale;
this.regenerateMap = function () {
var date = new Date();
pn = new Perlin('rnd' + date.getTime());
fillWithPerlin(pn, ctx);
cube.material.bumpMap.needsUpdate = true;
};
this.updateScale = function () {
cube.material.bumpScale = controls.bumpScale;
}
};
var gui = new dat.GUI();
gui.add(controls, "regenerateMap");
gui.add(controls, "bumpScale", -2, 2).onChange(controls.updateScale);
render();
function createMesh(geom, texture) {
var texture = new THREE.TextureLoader().load("../assets96/textures/general/" + texture);
var bumpMap = new THREE.Texture(canvas);
geom.computeVertexNormals();
var mat = new THREE.MeshPhongMaterial();
mat.color = new THREE.Color(0x77ff77);
mat.bumpMap = bumpMap;
bumpMap.needsUpdate = true;
// create a multimaterial
var mesh = new THREE.Mesh(geom, mat);
return mesh;
}
function render() {
stats.update();
cube.rotation.y += 0.01;
cube.rotation.x += 0.01;
// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}
function initStats() {
var stats = new Stats();
stats.setMode(0); // 0: fps, 1: ms
// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left = '0px';
stats.domElement.style.top = '0px';
document.getElementById("Stats-output").appendChild(stats.domElement);
return stats;
}
}
window.onload = init;
</script>
</body>
</html>
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