Three.js r72 - Texture marked for update but image is undefined?

问题

Three.js r72

I'm trying to use the same texture with different offsets and repeats, but after I clone the texture and apply needsUpdate I keep getting an error "Texture marked for update but image is undefined". I check the cloned texture and the image property is undefined. Shouldn't the clone method have referenced the source image from the texture in the textures Object.

var textures = {}
var materials = {}

textures.skin = THREE.ImageUtils.loadTexture('skin.png');
textures.skin.minFilter = THREE.NearestFilter;
textures.skin.magFilter = THREE.NearestFilter;
skin.map_data.forEach(function(item) {
    var mats = []
    item.maps.forEach(function(item) {
        var tex = textures.skin.clone();
        tex.needsUpdate = true;
        tex.offset.x = ((1 / skin.width) * item.offset_x)
        tex.offset.y = ((1 / skin.height) * item.offset_y)
        tex.repeat.x = ((1 / skin.width) * item.width);
        tex.repeat.y = ((1 / skin.height) * item.height);
        var mat = new THREE.MeshBasicMaterial({
            map: tex
        });
        mats.push(mat);
    })
    materials[item.name] = new THREE.MeshFaceMaterial(mats)
})

回答1:

Texture loading is asynchronous. You need to put the bulk of your code in the loader callback.

texture = THREE.ImageUtils.loadTexture( 'filename.jpg', undefined, function() {

    // the rest of your code here...

    var tex = texture.clone();
    tex.needsUpdate = true;

}

See how it is done in http://threejs.org/examples/misc_ubiquity_test2.html.

three.js r.72

来源：https://stackoverflow.com/questions/32984599/three-js-r72-texture-marked-for-update-but-image-is-undefined