变形动画非常简单,知道所有顶点的位置,然后将每个顶点从一个位置迁移到下一个位置即可。
骨骼和蒙皮则比较复杂,使用骨骼来做动画时,移动一下骨骼需要迁移附着在骨骼上的皮肤以及一些列的顶点的变动。
1、示例
示例
http://ithanmang.com/threeJs/home/201809/20180904/04-bones-manually.html
效果
这是一个手的模型,文件中带有骨骼bones
,顶点和面的定义。
2、实现步骤
2.1、加载模型并创建骨骼网格
let loader= new THREE.JSONLoader();
loader.load('../../models/json/hand-1.json', function (geometry) {
let material = new THREE.MeshNormalMaterial({skinning: true});
// 创建骨骼变形网格
mesh = new THREE.SkinnedMesh(geometry, material);
mesh.scale.set(10, 10, 10);
scene.add(mesh);
}
注意:需要把模型材质的skinning
属性设置为true
。
2.2、创建补间动画
通过补间动画来动态修改顶点的位置
/* 初始化补间动画 */
function initTween() {
let callback = function () {
let pos = this.pos;
// 旋转手指
mesh.skeleton.bones[5].rotation.set(0, 0, pos);
mesh.skeleton.bones[6].rotation.set(0, 0, pos);
mesh.skeleton.bones[10].rotation.set(0, 0, pos);
mesh.skeleton.bones[11].rotation.set(0, 0, pos);
mesh.skeleton.bones[15].rotation.set(0, 0, pos);
mesh.skeleton.bones[16].rotation.set(0, 0, pos);
mesh.skeleton.bones[20].rotation.set(0, 0, pos);
mesh.skeleton.bones[21].rotation.set(0, 0, pos);
// 旋转手腕
mesh.skeleton.bones[1].rotation.set(pos, 0, 0);
};
tween = new TWEEN.Tween({pos: -1})
.to({pos:0}, 3000)
.easing(TWEEN.Easing.Cubic.InOut)
.yoyo(true)
.repeat(Infinity)
.onUpdate(callback);
}
3、示例代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<link rel="icon" href="../../../three.png">
<title>用骨骼和蒙皮制作动画</title>
<style>
body {
margin: 0;
overflow: hidden; /* 溢出隐藏 */
}
#loading {
position: fixed;
top: 50%;
left: 50%;
color: #FFFFFF;
font-size: 20px;
margin-top: -30px;
margin-left: -40px;
}
</style>
<script src="../../libs/build/three-r93.js"></script>
<script src="../../libs/examples/js/Detector.js"></script>
<script src="../../libs/examples/js/libs/dat.gui.min.js"></script>
<script src="../../libs/examples/js/libs/stats.min.js"></script>
<script src="../../libs/examples/js/controls/OrbitControls.js"></script>
<script src="../../libs/tween/Tween.js"></script>
</head>
<body>
<p id="loading">loading......</p>
<script>
let scene, camera, renderer, controls, guiControls, tween;
let stats = initStats();
/* 场景 */
function initScene() {
scene = new THREE.Scene();
scene.background = new THREE.Color(0x050505);
}
/* 相机 */
function initCamera() {
camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 10000);
camera.position.set(0, -50, -20);
camera.lookAt(new THREE.Vector3(0, 0, 0));
}
/* 渲染器 */
function initRender() {
renderer = new THREE.WebGLRenderer({antialias: true});
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
}
/* 灯光 */
function initLight() {
scene.add(new THREE.AmbientLight(0x0c0c0c));
let spotLight = new THREE.SpotLight(0xffffff);
spotLight.position.set(-400, -400, -400);
let spotLight2 = new THREE.SpotLight(0xffffff);
spotLight2.position.set(400, 800, 400);
scene.add(spotLight);
scene.add(spotLight2);
}
/* 控制器 */
function initControls() {
/* 地图控件 */
controls = new THREE.OrbitControls(camera, renderer.domElement);
/* 属性参数 */
}
/* 调试插件 */
function initGui() {
guiControls = new function () {
this.skeletonHelper = true;
};
let gui = new dat.GUI();
gui.add(guiControls, 'skeletonHelper').onChange(function (e) {
skeletonHelper.visible = e;
});
}
/* 场景中的内容 */
let mesh;
let skeletonHelper;
function initContent() {
let loader= new THREE.JSONLoader();
loader.load('../../models/json/hand-1.json', function (geometry) {
let material = new THREE.MeshNormalMaterial({skinning: true});
// 创建骨骼变形网格
mesh = new THREE.SkinnedMesh(geometry, material);
mesh.scale.set(10, 10, 10);
scene.add(mesh);
skeletonHelper = new THREE.SkeletonHelper(mesh);
skeletonHelper.material.linewidth = 3;
scene.add(skeletonHelper);
tween.start();
removeLoading();
});
}
/* 初始化补间动画 */
function initTween() {
let callback = function () {
let pos = this.pos;
// 旋转手指
mesh.skeleton.bones[5].rotation.set(0, 0, pos);
mesh.skeleton.bones[6].rotation.set(0, 0, pos);
mesh.skeleton.bones[10].rotation.set(0, 0, pos);
mesh.skeleton.bones[11].rotation.set(0, 0, pos);
mesh.skeleton.bones[15].rotation.set(0, 0, pos);
mesh.skeleton.bones[16].rotation.set(0, 0, pos);
mesh.skeleton.bones[20].rotation.set(0, 0, pos);
mesh.skeleton.bones[21].rotation.set(0, 0, pos);
// 旋转手腕
mesh.skeleton.bones[1].rotation.set(pos, 0, 0);
};
tween = new TWEEN.Tween({pos: -1})
.to({pos:0}, 3000)
.easing(TWEEN.Easing.Cubic.InOut)
.yoyo(true)
.repeat(Infinity)
.onUpdate(callback);
}
/* 性能插件 */
function initStats() {
let stats = new Stats();
document.body.appendChild(stats.domElement);
return stats;
}
/* 窗口变动触发 */
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
}
/* 移除加载元素 */
function removeLoading() {
document.getElementById('loading').style.display = 'none';
}
/* 数据更新 */
function update() {
TWEEN.update();
stats.update();
controls.update();
}
/* 初始化 */
function init() {
initScene();
initCamera();
initRender();
initLight();
initControls();
initContent();
initGui();
initTween();
/* 监听事件 */
window.addEventListener('resize', onWindowResize, false);
}
/* 循环渲染 */
function animate() {
requestAnimationFrame(animate);
renderer.render(scene, camera);
update();
}
/* 初始加载 */
(function () {
console.log("three init start...");
init();
animate();
console.log("three init end...");
})();
</script>
</body>
</html>