3d位置到屏幕坐标不正常三js [r100]

问题描述 投票:0回答:1

我有一个非常简单的测试场景,可以在场景中的3d对象的位置放置一堆html标签。但是,当我尝试将3d坐标转换为屏幕位置时,我会得到奇怪的值,这些值根本不会与我的3d对象的位置发生冲突。请参阅下面的代码,我将使用该代码生成场景并放置标签:

var CanvasContainer = document.getElementById("KettingContainer");

function CameraSetup(container){
    var camera = new THREE.PerspectiveCamera( 50, container.offsetWidth / container.offsetHeight, 1, 300 );
    camera.position.set( 0, 0, 100 );
    camera.lookAt( 0, 0, 0 );
    return camera;
}

function SceneSetup(){
    var scene = new THREE.Scene();
    return scene;
}

function RenderSetup(container) {
    var renderer = new THREE.WebGLRenderer({ alpha: true });
    renderer.autoClear = false;
    renderer.setClearColor( 0x000000, 0 );
    renderer.setPixelRatio( window.devicePixelRatio );
    renderer.setSize( container.offsetWidth, container.offsetHeight );
    container.appendChild( renderer.domElement );
    return renderer;
}

function OnWindowResize(container){
    camera.aspect = container.offsetWidth / container.offsetHeight;
    camera.updateProjectionMatrix();
    renderer.setSize( container.offsetWidth, container.offsetHeight );
}

var kraalLabels = document.getElementById('kraalLinkLabels').getElementsByTagName('div');

function Animate(){
    requestAnimationFrame(Animate);

    Render();
}

function Render(){
    renderer.render( scene, camera );
}

function createScreenVector(pos, camera, width, height) {
    const hw = width/2, hh = height/2;
    var pos2d = pos.clone();
    pos2d.project(camera);
    console.log(pos2d);
    pos2d.x = ( pos2d.x * hw ) + hw;
    pos2d.y = - ( pos2d.y * hh ) + hh;

    return pos2d;
}

function positionLabels(positions, camera, width, height){
    for( var i = 0; i < kraalLabels.length; i++ )
    {
        const d = createScreenVector(positions, camera, width, height);
        kraalLabels[i].style.left = d.x + "px";
        kraalLabels[i].style.top = d.y + "px";
    }
}

var camera = CameraSetup(CanvasContainer);
var scene = SceneSetup();
var renderer = RenderSetup(CanvasContainer);

console.log("fc: ", camera.position);

const geometry = new THREE.SphereGeometry( 10, 32, 32 );
const material = new THREE.MeshBasicMaterial( {color: 0xff0000} );
let sphere = new THREE.Mesh( geometry, material );
sphere.position.set(20, 20, 0.1);
scene.add( sphere );

positionLabels(new THREE.Vector3(20, 20, 0.1), camera, CanvasContainer.offsetWidth, CanvasContainer.offsetHeight);

window.addEventListener("resize", function(){ OnWindowResize(CanvasContainer); }, false);
Animate();

请参阅下面的相机位置,画布容器大小和每个标签的屏幕位置的屏幕截图:

fc is the position of the camera

正如您所看到的,标签的位置比画布本身大得多。这些职位都是负面的......

即使我的对象只是在屏幕中心的顶部和左侧。

我完全被困在这个时候我不知道我做错了什么:(

如果需要额外的信息,我很乐意澄清!

javascript canvas three.js 3d 2d
1个回答
1
投票

在几个小时后搜索一个解决方案后,我终于在你做vector3.project(camera);之前找到了问题,你必须像这样更新相机矩阵:camera.updateMatrixWorld();这将解决奇怪值的问题。

希望这有助于未来的人!

© www.soinside.com 2019 - 2024. All rights reserved.