我想在three.js中制作一个测量工具，并使用reycaster函数来完成它。 当我在场景中使用Geometry时，它很好。
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>ytest</title>
<script src="JSandCSS/three.js"></script>
<script src="JSandCSS/OrbitControls.js"></script>
<script src="JSandCSS/OBJLoader.js"></script>
<script src="JSandCSS/Raycaster.js"></script>
</head>
<body>
<script>
var scene = new THREE.Scene();
var group = new THREE.Group;
var mouse = new THREE.Vector2();
var raycaster = new THREE.Raycaster();
var objects = [];
var particleMaterial;
particlecount = 0;
var container, stats, titleinfo;
scene.add(group);
var geometry = new THREE.SphereGeometry(5, 32, 32);
geometry.scale(10, 10, 10);
var material = new THREE.MeshBasicMaterial({
color: 0xffff00
});
var sphere = new THREE.Mesh(geometry, material);
group.add(sphere);
objects.push(sphere);
var light = new THREE.PointLight(0xffffff);
light.position.set(300, 400, 200);
light.intensity.set = 0.1;
scene.add(light);
scene.add(new THREE.AmbientLight(0x333333));
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
camera.position.set(200, 200, 200);
var renderer = new THREE.WebGLRenderer({
antialias: true
});
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
renderer.render(scene, camera);
renderer.setClearColor(0x808080, 0.5);
render();
var controls = new THREE.OrbitControls(camera);
controls.addEventListener('change', render);
animate();
window.addEventListener('resize', handleWindowResize, false);
window.addEventListener('mousedown', onDocumentMouseDown, false);
function onDocumentMouseDown(event) {
event.preventDefault();
mouse.x = (event.clientX / renderer.domElement.clientWidth) * 2 - 1;
mouse.y = -(event.clientY / renderer.domElement.clientHeight) * 2 + 1;
raycaster.setFromCamera(mouse, camera);
var intersects = raycaster.intersectObjects(objects);
var PI2 = Math.PI * 2;
var pointLoader = new THREE.TextureLoader();
particleMaterial = new THREE.SpriteMaterial({
map: pointLoader.load("pic/measurepoint.png"),
});
if(intersects.length > 0) {
if(particlecount == 0) {
var particle1 = new THREE.Sprite(particleMaterial);
particle1.name = 'particle1';
particle1.position.copy(intersects[0].point);
particle1.scale.x = particle1.scale.y = 5;
scene.add(particle1);
particlecount = 1;
} else {
if(particlecount !== 2) {
var particle2 = new THREE.Sprite(particleMaterial);
particle2.name = 'particle2';
particle2.position.copy(intersects[0].point);
particle2.scale.x = particle2.scale.y = 5;
scene.add(particle2);
particlecount = 2;
a = scene.getObjectByName('particle1');
b = scene.getObjectByName('particle2');
var dis = a.position.distanceTo(b.position);
alert('distance between two point is' + dis);
scene.remove(a);
scene.remove(b);
particlecount = 0;
}
}
}
}
function render() {
renderer.render(scene, camera);
}
function animate() {
requestAnimationFrame(animate);
render();
}
function handleWindowResize() {
HEIGHT = window.innerHeight;
WIDTH = window.innerWidth;
renderer.setSize(WIDTH, HEIGHT);
camera.aspect = WIDTH / HEIGHT;
camera.updateProjectionMatrix();
}
</script>
</body>
</html>
enter image description here 但是当我加载模型时，它不起作用。当你看到＆＃34; alert（intersects.length）＆＃34;的结果时。是0。
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>ytest</title>
<script src="JSandCSS/three.js"></script>
<script src="JSandCSS/OrbitControls.js"></script>
<script src="JSandCSS/OBJLoader.js"></script>
<script src="JSandCSS/Raycaster.js"></script>
</head>
<body>
<script>
var scene = new THREE.Scene();
var group = new THREE.Group;
var mouse = new THREE.Vector2();
var raycaster = new THREE.Raycaster();
var objects = [];
var particleMaterial;
particlecount = 0;
var container, stats, titleinfo;
scene.add(group);
var textureLoader = new THREE.TextureLoader();
var mat = new THREE.MeshLambertMaterial({
map: textureLoader.load("model/earth/texture.jpg"),
specularMap: textureLoader.load("model/earth/specular.jpg"),
lightMap: textureLoader.load("model/earth/light.jpg")
});
var loader = new THREE.OBJLoader();
loader.load('model/earth/earth.obj',
function chuanzhi(obj) {
obj.traverse(function(child) {
if(child instanceof THREE.Mesh) {
child.material = mat;
}
});
Mesh = obj;
obj.scale.set(2, 2, 2);
group.add(obj);
objects.push(Mesh);
});
var light = new THREE.PointLight(0xffffff);
light.position.set(300, 400, 200);
light.intensity.set = 0.1;
scene.add(light);
scene.add(new THREE.AmbientLight(0x333333));
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
camera.position.set(200, 200, 200);
camera.lookAt(scene.position);
var renderer = new THREE.WebGLRenderer({
antialias: true
});
renderer.setSize(window.innerWidth, window.innerHeight);
document.body.appendChild(renderer.domElement);
renderer.render(scene, camera);
renderer.setClearColor(0x808080, 0.5);
render();
var controls = new THREE.OrbitControls(camera);
controls.addEventListener('change', render);
animate();
window.addEventListener('resize', handleWindowResize, false);
window.addEventListener('mousedown', onDocumentMouseDown, false);
function onDocumentMouseDown(event) {
event.preventDefault();
mouse.x = (event.clientX / renderer.domElement.clientWidth) * 2 - 1;
mouse.y = -(event.clientY / renderer.domElement.clientHeight) * 2 + 1;
raycaster.setFromCamera(mouse, camera);
var intersects = raycaster.intersectObjects(objects);
var PI2 = Math.PI * 2;
var pointLoader = new THREE.TextureLoader();
particleMaterial = new THREE.SpriteMaterial({
map: pointLoader.load("pic/measurepoint.png"),
});
alert(intersects.length);
if(intersects.length > 0) {
if(particlecount == 0) {
var particle1 = new THREE.Sprite(particleMaterial);
particle1.name = 'particle1';
particle1.position.copy(intersects[0].point);
particle1.scale.x = particle1.scale.y = 5;
scene.add(particle1);
particlecount = 1;
} else {
if(particlecount !== 2) {
var particle2 = new THREE.Sprite(particleMaterial);
particle2.name = 'particle2';
particle2.position.copy(intersects[0].point);
particle2.scale.x = particle2.scale.y = 5;
scene.add(particle2);
particlecount = 2;
a = scene.getObjectByName('particle1');
b = scene.getObjectByName('particle2');
var dis = a.position.distanceTo(b.position);
alert('distance between two point is' + dis);
scene.remove(a);
scene.remove(b);
particlecount = 0;
}
}
}
}
function render() {
renderer.render(scene, camera);
}
function animate() {
requestAnimationFrame(animate);
render();
}
function handleWindowResize() {
HEIGHT = window.innerHeight;
WIDTH = window.innerWidth;
renderer.setSize(WIDTH, HEIGHT);
camera.aspect = WIDTH / HEIGHT;
camera.updateProjectionMatrix();
}
</script>
</body>
</html>
我想知道它为什么会发生，以及我如何正确使用它。你能帮助我吗？