我正在尝试使用三个 JS 制作一个看起来像这样的 blender-esk 方向 View :
我的计划是让相机旋转并旋转 3 个矢量点(代表图片中的 X、Y 和 Z 气泡)。然后,一旦我有了这些点,我就可以使用 X 和 Y 坐标在 Canvas 上绘制圆圈并绘制线条以将它们连接到中心。然后我可以使用 Z 方向来确定应该在什么之上绘制什么。
目前我正在使用第二个 three.js 场景来可视化这些 X、Y 和 Z 点的位置,因为我尝试了不同的方法来旋转顶点组以使其与相机的方向匹配。我在这部分苦苦挣扎,我尝试了很多没有用的东西。
这是我目前所在位置的 JS Fiddle:
https://jsfiddle.net/j9mcL0x4/4/
(在 Brave 中不加载,但在 Chrome 中有效)
当您平移相机时,它会移动第二个场景中的 3 个立方体,但我无法让它正确旋转。
X、Y 和 Z 点由一组 Vector3 表示,如下所示:
this.ref = [
[new THREE.Vector3(1,0,0), 0xFF0000],
[new THREE.Vector3(0,1,0), 0x00FF00],
[new THREE.Vector3(0,0,1), 0x0000FF],
]
然后我创建每个多维数据集并将其添加到一个组中:this.group = new THREE.Group();
for(var pos of this.ref) {
var geometry = new THREE.BoxGeometry(.25,.25,.25);
var material = new THREE.MeshBasicMaterial({
color: pos[1]
});
var cube = new THREE.Mesh(geometry, material);
cube.position.copy(pos[0]);
this.group.add(cube);
}
this.scene.add(this.group);
然后在我的动画函数中,我试图计算组的旋转以使其与主视图的方向相同:var quaternion = new THREE.Quaternion();
camera.getWorldQuaternion( quaternion );
let rotation = new THREE.Euler();
rotation.setFromQuaternion(quaternion);
var dir = new THREE.Vector3();
dir.subVectors( camera.position, controls.target ).normalize();
orientationHelper.group.rotation.set(dir.x, dir.y, dir.z);
orientationHelper.animate();
我所拥有的是完全错误的,但这是我尝试过的一些事情:备注
我可以在第二个场景中旋转相机以匹配主视图中的相机,但我真的想自己旋转矢量。这样我就可以将这些点投影到基本 Canvas 上以绘制 6 个圆圈和 3 条线。我觉得这比尝试在 3d 中使用 Sprite 要容易得多,而且三个 JS 在不为其创建矩形网格的情况下无法轻松绘制粗线。
以下是我希望输出看起来像的一些示例:
更新
Rabbid76 解决了这个问题,如果有人有兴趣在他们的项目中使用 Blender 风格的方位立方体,你可以在这里找到完整的源代码:
https://github.com/jrj2211/three-orientation-gizmo/
或者使用 npm 下载:
https://www.npmjs.com/package/three-orientation-gizmo
最佳答案
首先在 View 空间中,X 轴指向右侧,Y 轴指向上方,Z 轴指向 Canvas 外。
所以你必须为 OrientationHelper
选择一个初始位置。正 Z 轴上的相机:
class OrientationHelper {
constructor(canvas) {
// [...]
this.camera = new THREE.PerspectiveCamera(75, size / size, 0.1, 1000);
this.camera.position.set(0, 0, 2);
// [...]
在下文中,我建议在
OrientationHelper
中设置组的方向。矩阵场景:class OrientationHelper {
// [...]
setCameraRotation(rotation) {
this.group.setRotationFromMatrix(rotation);
}
// [...]
View 矩阵是该矩阵的逆矩阵,它定义了相机的位置和方向。您想要可视化相机的方向。您想要可视化 View 矩阵的方向。
从
camera.rotation
创建一个旋转矩阵.计算 Inverse matrix并设置 OrientationHelper
的方向通过计算矩阵:let rotMat = new THREE.Matrix4().makeRotationFromEuler(camera.rotation);
let invRotMat = new THREE.Matrix4().getInverse(rotMat);
orientationHelper.setCameraRotation(invRotMat);
orientationHelper.update();
请参阅示例:
class OrientationHelper {
constructor(canvas) {
this.canvas = canvas;
this.ref = [
[new THREE.Vector3(1,0,0), 0xFF0000],
[new THREE.Vector3(0,1,0), 0x00FF00],
[new THREE.Vector3(0,0,1), 0x0000FF],
]
var size = 200;
this.scene = new THREE.Scene();
this.camera = new THREE.PerspectiveCamera(75, size / size, 0.1, 1000);
this.camera.position.set(0, 0, 2);
this.renderer = new THREE.WebGLRenderer({alpha: true});
this.renderer.setSize(size, size);
canvas.appendChild(this.renderer.domElement);
var controls = new THREE.OrbitControls(this.camera, this.renderer.domElement);
var geometry = new THREE.SphereGeometry( .1, 32, 32 );
var material = new THREE.MeshBasicMaterial( {color: 0xffffff} );
var sphere = new THREE.Mesh( geometry, material );
this.scene.add( sphere );
this.group = new THREE.Group();
for(var pos of this.ref) {
var geometry = new THREE.BoxGeometry(.25,.25,.25);
var material = new THREE.MeshBasicMaterial({
color: pos[1]
});
var cube = new THREE.Mesh(geometry, material);
cube.position.copy(pos[0]);
this.group.add(cube);
}
this.scene.add(this.group);
}
setCameraRotation(rotation) {
this.group.setRotationFromMatrix(rotation);
}
update() {
this.renderer.render(this.scene, this.camera);
}
}
var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
var renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
var controls = new THREE.OrbitControls(camera, renderer.domElement);
camera.position.set(0, 3, 3);
controls.update();
//controls.autoRotate = true;
var size = 10;
var divisions = 10;
var gridHelper = new THREE.GridHelper(size, divisions);
scene.add(gridHelper);
var axesHelper = new THREE.AxesHelper(5);
scene.add(axesHelper);
// material
var material = new THREE.MeshBasicMaterial({
color: 0xffffff,
vertexColors: THREE.FaceColors
});
var geometry = new THREE.BoxGeometry();
// colors
red = new THREE.Color(1, 0, 0);
green = new THREE.Color(0, 1, 0);
blue = new THREE.Color(0, 0, 1);
var colors = [red, green, blue];
for (var i = 0; i < 3; i++) {
geometry.faces[4 * i].color = colors[i];
geometry.faces[4 * i + 1].color = colors[i];
geometry.faces[4 * i + 2].color = colors[i];
geometry.faces[4 * i + 3].color = colors[i];
}
var cube = new THREE.Mesh(geometry, material);
scene.add(cube);
// Orientation
var orientationHelper = new OrientationHelper(document.getElementById("orientation-helper"));
function animate() {
requestAnimationFrame(animate);
controls.update();
let rotMat = new THREE.Matrix4().makeRotationFromEuler(camera.rotation);
let invRotMat = new THREE.Matrix4().getInverse(rotMat);
orientationHelper.setCameraRotation(invRotMat);
orientationHelper.update();
renderer.render(scene, camera);
}
animate();
body { margin: 0; }
canvas { display: block; }
#orientation-helper { position: absolute; top: 10px; left: 10px; background: #505050; }
<script src="https://rawcdn.githack.com/mrdoob/three.js/r113/build/three.js"></script>
<script src="https://rawcdn.githack.com/mrdoob/three.js/r113/examples/js/controls/OrbitControls.js"></script>
<div id='orientation-helper'></div>
关于javascript - 三个 JS 旋转组,与 View Cube/Orientation Cube 的相机方向相同,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/60245700/