I am starting with THREE.js, and I am trying to draw a rectangle with a texture on it, lit by a single source of light. I think this is as simple as it gets (HTML omitted for brevity):
function loadScene() {
var world = document.getElementById('world'),
WIDTH = 1200,
HEIGHT = 500,
VIEW_ANGLE = 45,
ASPECT = WIDTH / HEIGHT,
NEAR = 0.1,
FAR = 10000,
renderer = new THREE.WebGLRenderer(),
camera = new THREE.Camera(VIEW_ANGLE, ASPECT, NEAR, FAR),
scene = new THREE.Scene(),
texture = THREE.ImageUtils.loadTexture('crate.gif'),
material = new THREE.MeshBasicMaterial({map: texture}),
// material = new THREE.MeshPhongMaterial({color: 0xCC0000});
geometry = new THREE.PlaneGeometry(100, 100),
mesh = new THREE.Mesh(geometry, material),
pointLight = new THREE.PointLight(0xFFFFFF);
camera.position.z = 200;
renderer.setSize(WIDTH, HEIGHT);
scene.addChild(mesh);
world.appendChild(renderer.domElement);
pointLight.position.x = 50;
pointLight.position.y = 50;
pointLight.position.z = 130;
scene.addLight(pointLight);
renderer.render(scene, camera);
}
The problem is, I cannot see anything. If I change the material and use the commented one, a square appears as I would expect. Note that
- The texture is 256x256, so its sides are power of two
- The function is actually called when the body is loaded; indeed it works with a different material.
- It does not work even if I serve the file from a webserver, so it is not an issue of cross-domain policy not allowing to load the image.
What I am I doing wrong?
Answer
By the time the image is loaded, the renderer has already drawn the scene, hence it is too late. The solution is to change
texture = THREE.ImageUtils.loadTexture('crate.gif'),
into
texture = THREE.ImageUtils.loadTexture('crate.gif', {}, function() {
renderer.render(scene);
}),