You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
300 lines
7.1 KiB
HTML
300 lines
7.1 KiB
HTML
<!-- Licensed under a BSD license. See license.html for license -->
|
|
<!DOCTYPE html>
|
|
<html>
|
|
<head>
|
|
<meta charset="utf-8">
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=yes">
|
|
<title>Three.js - Picking - RayCaster w/Transparency</title>
|
|
<style>
|
|
html, body {
|
|
height: 100%;
|
|
margin: 0;
|
|
}
|
|
#c {
|
|
width: 100%;
|
|
height: 100%;
|
|
display: block;
|
|
}
|
|
</style>
|
|
</head>
|
|
<body>
|
|
<canvas id="c"></canvas>
|
|
</body>
|
|
<script type="importmap">
|
|
{
|
|
"imports": {
|
|
"three": "../../build/three.module.js"
|
|
}
|
|
}
|
|
</script>
|
|
|
|
<script type="module">
|
|
import * as THREE from 'three';
|
|
|
|
function main() {
|
|
|
|
const canvas = document.querySelector( '#c' );
|
|
const renderer = new THREE.WebGLRenderer( { antialias: true, canvas } );
|
|
|
|
const fov = 60;
|
|
const aspect = 2; // the canvas default
|
|
const near = 0.1;
|
|
const far = 200;
|
|
const camera = new THREE.PerspectiveCamera( fov, aspect, near, far );
|
|
camera.position.z = 30;
|
|
|
|
const scene = new THREE.Scene();
|
|
scene.background = new THREE.Color( 'white' );
|
|
const pickingScene = new THREE.Scene();
|
|
pickingScene.background = new THREE.Color( 0 );
|
|
|
|
// put the camera on a pole (parent it to an object)
|
|
// so we can spin the pole to move the camera around the scene
|
|
const cameraPole = new THREE.Object3D();
|
|
scene.add( cameraPole );
|
|
cameraPole.add( camera );
|
|
|
|
{
|
|
|
|
const color = 0xFFFFFF;
|
|
const intensity = 3;
|
|
const light = new THREE.DirectionalLight( color, intensity );
|
|
light.position.set( - 1, 2, 4 );
|
|
camera.add( light );
|
|
|
|
}
|
|
|
|
const boxWidth = 1;
|
|
const boxHeight = 1;
|
|
const boxDepth = 1;
|
|
const geometry = new THREE.BoxGeometry( boxWidth, boxHeight, boxDepth );
|
|
|
|
function rand( min, max ) {
|
|
|
|
if ( max === undefined ) {
|
|
|
|
max = min;
|
|
min = 0;
|
|
|
|
}
|
|
|
|
return min + ( max - min ) * Math.random();
|
|
|
|
}
|
|
|
|
function randomColor() {
|
|
|
|
return `hsl(${rand( 360 ) | 0}, ${rand( 50, 100 ) | 0}%, 50%)`;
|
|
|
|
}
|
|
|
|
const loader = new THREE.TextureLoader();
|
|
const texture = loader.load( 'resources/images/frame.png' );
|
|
|
|
const idToObject = {};
|
|
const numObjects = 100;
|
|
for ( let i = 0; i < numObjects; ++ i ) {
|
|
|
|
const id = i + 1;
|
|
const material = new THREE.MeshPhongMaterial( {
|
|
color: randomColor(),
|
|
map: texture,
|
|
transparent: true,
|
|
side: THREE.DoubleSide,
|
|
alphaTest: 0.5,
|
|
} );
|
|
|
|
const cube = new THREE.Mesh( geometry, material );
|
|
scene.add( cube );
|
|
idToObject[ id ] = cube;
|
|
|
|
cube.position.set( rand( - 20, 20 ), rand( - 20, 20 ), rand( - 20, 20 ) );
|
|
cube.rotation.set( rand( Math.PI ), rand( Math.PI ), 0 );
|
|
cube.scale.set( rand( 3, 6 ), rand( 3, 6 ), rand( 3, 6 ) );
|
|
|
|
const pickingMaterial = new THREE.MeshPhongMaterial( {
|
|
emissive: new THREE.Color().setHex( id, THREE.NoColorSpace ),
|
|
color: new THREE.Color( 0, 0, 0 ),
|
|
specular: new THREE.Color( 0, 0, 0 ),
|
|
map: texture,
|
|
transparent: true,
|
|
side: THREE.DoubleSide,
|
|
alphaTest: 0.5,
|
|
blending: THREE.NoBlending,
|
|
} );
|
|
const pickingCube = new THREE.Mesh( geometry, pickingMaterial );
|
|
pickingScene.add( pickingCube );
|
|
pickingCube.position.copy( cube.position );
|
|
pickingCube.rotation.copy( cube.rotation );
|
|
pickingCube.scale.copy( cube.scale );
|
|
|
|
}
|
|
|
|
function resizeRendererToDisplaySize( renderer ) {
|
|
|
|
const canvas = renderer.domElement;
|
|
const width = canvas.clientWidth;
|
|
const height = canvas.clientHeight;
|
|
const needResize = canvas.width !== width || canvas.height !== height;
|
|
if ( needResize ) {
|
|
|
|
renderer.setSize( width, height, false );
|
|
|
|
}
|
|
|
|
return needResize;
|
|
|
|
}
|
|
|
|
class GPUPickHelper {
|
|
|
|
constructor() {
|
|
|
|
// create a 1x1 pixel render target
|
|
this.pickingTexture = new THREE.WebGLRenderTarget( 1, 1 );
|
|
this.pixelBuffer = new Uint8Array( 4 );
|
|
this.pickedObject = null;
|
|
this.pickedObjectSavedColor = 0;
|
|
|
|
}
|
|
pick( cssPosition, scene, camera, time ) {
|
|
|
|
const { pickingTexture, pixelBuffer } = this;
|
|
|
|
// restore the color if there is a picked object
|
|
if ( this.pickedObject ) {
|
|
|
|
this.pickedObject.material.emissive.setHex( this.pickedObjectSavedColor );
|
|
this.pickedObject = undefined;
|
|
|
|
}
|
|
|
|
// set the view offset to represent just a single pixel under the mouse
|
|
const pixelRatio = renderer.getPixelRatio();
|
|
camera.setViewOffset(
|
|
renderer.getContext().drawingBufferWidth, // full width
|
|
renderer.getContext().drawingBufferHeight, // full top
|
|
cssPosition.x * pixelRatio | 0, // rect x
|
|
cssPosition.y * pixelRatio | 0, // rect y
|
|
1, // rect width
|
|
1, // rect height
|
|
);
|
|
// render the scene
|
|
renderer.setRenderTarget( pickingTexture );
|
|
renderer.render( scene, camera );
|
|
renderer.setRenderTarget( null );
|
|
// clear the view offset so rendering returns to normal
|
|
camera.clearViewOffset();
|
|
//read the pixel
|
|
renderer.readRenderTargetPixels(
|
|
pickingTexture,
|
|
0, // x
|
|
0, // y
|
|
1, // width
|
|
1, // height
|
|
pixelBuffer );
|
|
|
|
const id =
|
|
( pixelBuffer[ 0 ] << 16 ) |
|
|
( pixelBuffer[ 1 ] << 8 ) |
|
|
( pixelBuffer[ 2 ] );
|
|
|
|
const intersectedObject = idToObject[ id ];
|
|
if ( intersectedObject ) {
|
|
|
|
// pick the first object. It's the closest one
|
|
this.pickedObject = intersectedObject;
|
|
// save its color
|
|
this.pickedObjectSavedColor = this.pickedObject.material.emissive.getHex();
|
|
// set its emissive color to flashing red/yellow
|
|
this.pickedObject.material.emissive.setHex( ( time * 8 ) % 2 > 1 ? 0xFFFF00 : 0xFF0000 );
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
const pickPosition = { x: 0, y: 0 };
|
|
const pickHelper = new GPUPickHelper();
|
|
clearPickPosition();
|
|
|
|
function render( time ) {
|
|
|
|
time *= 0.001; // convert to seconds;
|
|
|
|
if ( resizeRendererToDisplaySize( renderer ) ) {
|
|
|
|
const canvas = renderer.domElement;
|
|
camera.aspect = canvas.clientWidth / canvas.clientHeight;
|
|
camera.updateProjectionMatrix();
|
|
|
|
}
|
|
|
|
cameraPole.rotation.y = time * .1;
|
|
|
|
pickHelper.pick( pickPosition, pickingScene, camera, time );
|
|
|
|
renderer.render( scene, camera );
|
|
|
|
requestAnimationFrame( render );
|
|
|
|
}
|
|
|
|
requestAnimationFrame( render );
|
|
|
|
function getCanvasRelativePosition( event ) {
|
|
|
|
const rect = canvas.getBoundingClientRect();
|
|
return {
|
|
x: ( event.clientX - rect.left ) * canvas.width / rect.width,
|
|
y: ( event.clientY - rect.top ) * canvas.height / rect.height,
|
|
};
|
|
|
|
}
|
|
|
|
function setPickPosition( event ) {
|
|
|
|
const pos = getCanvasRelativePosition( event );
|
|
pickPosition.x = pos.x;
|
|
pickPosition.y = pos.y;
|
|
|
|
}
|
|
|
|
function clearPickPosition() {
|
|
|
|
// unlike the mouse which always has a position
|
|
// if the user stops touching the screen we want
|
|
// to stop picking. For now we just pick a value
|
|
// unlikely to pick something
|
|
pickPosition.x = - 100000;
|
|
pickPosition.y = - 100000;
|
|
|
|
}
|
|
|
|
window.addEventListener( 'mousemove', setPickPosition );
|
|
window.addEventListener( 'mouseout', clearPickPosition );
|
|
window.addEventListener( 'mouseleave', clearPickPosition );
|
|
|
|
window.addEventListener( 'touchstart', ( event ) => {
|
|
|
|
// prevent the window from scrolling
|
|
event.preventDefault();
|
|
setPickPosition( event.touches[ 0 ] );
|
|
|
|
}, { passive: false } );
|
|
|
|
window.addEventListener( 'touchmove', ( event ) => {
|
|
|
|
setPickPosition( event.touches[ 0 ] );
|
|
|
|
} );
|
|
|
|
window.addEventListener( 'touchend', clearPickPosition );
|
|
|
|
}
|
|
|
|
main();
|
|
</script>
|
|
</html>
|