Blending multiple transparent meshes causes strange behavior: only the first mesh is drawn, the inner meshes are hidden at the intersection. This only happens within a certain camera angle range.
Can is be fixed? Why does this only happen at certain angles?
Tested with r142
and r143
. Browser Chrome 104.0.5112.81
.
canvas {
position: absolute;
top: 0;
left: 0;
}
<script type="importmap">
{
"imports": {
"three": "https://unpkg.com/three@0.142.0/build/three.module.js",
"OrbitControls": "https://unpkg.com/three@0.142.0/examples/jsm/controls/OrbitControls.js"
}
}
</script>
<script type="module">
import * as THREE from "three";
import { OrbitControls } from "OrbitControls";
/* -- */
const renderer = new THREE.WebGLRenderer();
document.body.appendChild(renderer.domElement);
const scene = new THREE.Scene();
scene.background = new THREE.Color(0x111111);
const ambientLight = new THREE.AmbientLight(0xffffff);
scene.add(ambientLight);
const camera = new THREE.PerspectiveCamera(75, 1, 0.1, 1000);
camera.position.set(0, 0, 5);
const controls = new OrbitControls(camera, renderer.domElement);
/* -- */
const length = 7;
const points = [
new THREE.Vector3(0, -length / 2, 0),
new THREE.Vector3(0, length / 2, 0)
];
const curve = new THREE.CatmullRomCurve3(points);
const createMeshOnScene = (scene, geometry, material, position) => {
const mesh = new THREE.Mesh(geometry, material);
mesh.position.copy(position);
scene.add(mesh);
return mesh;
};
const transparentMaterial = (color) => {
return new THREE.MeshStandardMaterial({
color: color,
side: THREE.DoubleSide,
transparent: true,
opacity: 0.6,
metalness: 0,
roughness: 1
});
};
const opaqueMaterial = new THREE.MeshStandardMaterial({
color: 0xffffff,
metalness: 0,
roughness: 1
});
createMeshOnScene(
scene,
new THREE.TubeGeometry(curve, 2, 0.2, 16),
opaqueMaterial,
new THREE.Vector3(0, -0.4, 0)
);
createMeshOnScene(
scene,
new THREE.ConeGeometry(2, 2, 4, 1, true, 0, Math.PI * 1.6),
transparentMaterial(0xaa0000),
new THREE.Vector3(0, 0, 0)
);
createMeshOnScene(
scene,
new THREE.ConeGeometry(2, 2, 4, 1, true, 0, Math.PI * 1.6),
transparentMaterial(0xaaaa00),
new THREE.Vector3(0, -0.3, 0)
);
createMeshOnScene(
scene,
new THREE.ConeGeometry(2, 2, 4, 1, true, 0, Math.PI * 1.6),
transparentMaterial(0x00aa00),
new THREE.Vector3(0, -0.6, 0)
);
createMeshOnScene(
scene,
new THREE.ConeGeometry(2, 2, 4, 1, true, 0, Math.PI * 1.6),
transparentMaterial(0x00aaaa),
new THREE.Vector3(0, -0.9, 0)
);
/* -- */
function animate() {
requestAnimationFrame(animate);
renderer.render(scene, camera);
}
animate();
/* -- */
window.addEventListener("resize", resize);
function resize() {
let width = window.innerWidth;
let height = window.innerHeight;
camera.aspect = width / height;
camera.updateProjectionMatrix();
renderer.setSize(width, height);
}
resize();
</script>