(编辑:jimmy 日期: 2024/12/25 浏览:2)
因为之前的几节讲了一些数学方法,例如Vector3、Matrix4、Euler还有Quaternion的知识。所以这篇郭先生就来说说用three.js怎么制作一个魔方。
制作魔方主要运用坐标变换的知识,制作魔方的方法有很多,建议你先在大脑中构思,然后试着做一做,下面我将一种比较简单的方法。
以上是主要的步骤,但是对于新同学,需要注意的仍然很多,下面上主要代码,按照方法说
1. 定义的变量
posArr = [ [100,100,100],[100,100,0],[100,100,-100],[100,0,100],[100,0,0],[100,0,-100],[100,-100,100],[100,-100,0],[100,-100,-100], [0,100,100],[0,100,0],[0,100,-100],[0,0,100],[0,0,0],[0,0,-100],[0,-100,100],[0,-100,0],[0,-100,-100], [-100,100,100],[-100,100,0],[-100,100,-100],[-100,0,100],[-100,0,0],[-100,0,-100],[-100,-100,100],[-100,-100,0],[-100,-100,-100] ],//方块位置坐标 materials,//材质数组 mouse = new THREE.Vector2(),//通过鼠标点击的位置计算出raycaster所需要的点的位置,以屏幕中心为原点,值的范围为-1到1. raycaster,//射线对象 group,//存放魔方方块的数组 groupTemp,//魔方转动时临时数组 object3d,//魔方被选择面的标志物对象 currentPos,//魔方被点击小块的位置 currentNor,//魔方被点击小块面的法向量 currentUp,//魔方被点击时,相机up的向量
2. 定义材质数组
initMaterial() { var map_red = new THREE.TextureLoader().load('/static/images/color/m_red.jpg', () => this.loadover --); var map_orange = new THREE.TextureLoader().load('/static/images/color/m_orange.jpg', () => this.loadover --); var map_yellow = new THREE.TextureLoader().load('/static/images/color/m_yellow.jpg', () => this.loadover --); var map_blue = new THREE.TextureLoader().load('/static/images/color/m_blue.jpg', () => this.loadover --); var map_green = new THREE.TextureLoader().load('/static/images/color/m_green.jpg', () => this.loadover --); var map_white = new THREE.TextureLoader().load('/static/images/color/m_white.jpg', () => this.loadover --); var map_sprite = new THREE.TextureLoader().load('/static/images/base/direction.png', () => this.loadover --); let mater_red = new THREE.MeshBasicMaterial({map: map_red, side: THREE.DoubleSide}); let mater_orange = new THREE.MeshBasicMaterial({map: map_orange, side: THREE.DoubleSide}); let mater_yellow = new THREE.MeshBasicMaterial({map: map_yellow, side: THREE.DoubleSide}); let mater_white = new THREE.MeshBasicMaterial({map: map_white, side: THREE.DoubleSide}); let mater_blue = new THREE.MeshBasicMaterial({map: map_blue, side: THREE.DoubleSide}); let mater_green = new THREE.MeshBasicMaterial({map: map_green, side: THREE.DoubleSide}); materials = [mater_red, mater_orange, mater_yellow,mater_white, mater_blue, mater_green]; }
3. 绘制小方块并绘制标志物(先隐藏)
initsquare() { var sphereGeom = new THREE.SphereGeometry(10, 30, 20); var sphereMate = new THREE.MeshPhongMaterial({color: 0x333333}); object3d = new THREE.Mesh(sphereGeom, sphereMate); object3d.name = 'object3d'; object3d.visible = false; scene.add(object3d); group = new THREE.Group(); group.name = 'group'; var geometry = new THREE.BoxGeometry(100, 100, 100); var mesh = new THREE.Mesh(geometry, materials); posArr.forEach((d,i) => { let meshCopy = mesh.clone(); meshCopy.position.set(d[0], d[1], d[2]) meshCopy.name = 'box-' + i; group.add(meshCopy); }) scene.add(group); this.render(); document.getElementById("loading").style.display = "none"; }
4. 监听模型的点击事件
initEventListener() { raycaster = new THREE.Raycaster(); document.addEventListener('mousemove', function (event) { event.preventDefault(); mouse.x = (event.clientX / window.innerWidth) * 2 - 1; mouse.y = - (event.clientY / window.innerHeight) * 2 + 1; }, false) document.addEventListener('mousedown', () => { if (scene.children && scene.getObjectByName('group')) { raycaster.setFromCamera(mouse, camera); let intersects = raycaster.intersectObjects(scene.getObjectByName('group').children); if (intersects[0] && intersects[0].object.name != 'object3d') { let index = intersects[0].faceIndex; let point = intersects[0].point; currentUp = this.computedUp(camera); currentNor = this.computedNor(point) currentPos = intersects[0].object.position; let pos = this.computedPos(point); object3d.position.copy(pos); object3d.visible = true; } } }) }
5. 监听方向软键盘的点击,根据点击键的不同,生成旋转轴
handleRotate(num) { if(!rotateFlag || !currentPos) return ; rotateFlag = false; groupTemp = new THREE.Group(); groupTemp.name = 'group-temp'; let axis; let tempMeshArr = []; switch (num) { case 1: axis = currentNor.clone().cross(currentUp); break; case 2: axis = currentNor.clone().cross(currentUp).negate(); break; case 3: axis = currentUp.clone().negate(); break; case 4: axis = currentUp; break; } let plane = new THREE.Plane().setFromNormalAndCoplanarPoint(axis, currentPos); scene.getObjectByName('group').children.forEach(d => Math.abs(plane.distanceToPoint(d.position)) < 1 && tempMeshArr.push(d)) tempMeshArr.forEach(d => { group.remove(d); groupTemp.add(d); }) // object3d.visible = false; scene.remove(scene.getObjectByName('group-temp')); scene.add(groupTemp); this.handleTween(axis); }
6. 加一点tween的补间动画,效果更好哦
handleTween(axis) { let start = {angle: 0, axis}; let end = {angle: Math.PI/2, axis}; tween = new TWEEN.Tween(start).to(end, 500); tween.easing(TWEEN.Easing.Linear.None); tween.onUpdate(function () { let quaternion = new THREE.Quaternion().setFromAxisAngle(axis, this._object.angle); groupTemp.rotation.setFromQuaternion(quaternion); }); tween.onComplete(() => { let matrix = this.standerMatrix(groupTemp.matrix); groupTemp.children.forEach(d => { let mesh = d.clone(); mesh.applyMatrix4(matrix) mesh.position.copy(this.standarPos(mesh.position)) group.add(mesh); }) scene.remove(groupTemp) rotateFlag = true; }) tween.start(); }
郭先生制作魔方的主要思路就是先做出27个方块添加到组A,6个面分别添加不同颜色的贴图(自己p的哦),然后使用raycaster选择点击的面,并确定当时的up方向和法向量方向以备后用,点击上下左右并结合u方向和法向量方向计算出旋转矩阵,根据已有条件计算出是那一排方块改变,并将这9个块添加到组B中,从组A中删除这9个,根据旋转矩阵旋转组B,并且在旋转完之后将组B中的方块添加到组A中,旋转完毕(这里比较难的就是根据上下左右判断旋转轴向量)。
以上就是一种制作魔方的方法,综合了很多矩阵向量四元数欧拉角和平面的知识,希望对新来的同游有些帮助