<!-- 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 - Billboard Trees Static Billboards</title>
<style>
html, body {
height: 100%;
margin: 0;
}
#c {
width: 100%;
height: 100%;
display: block;
}
</style>
</head>
<body>
<canvas id="c"></canvas>
</body>
<!-- Import maps polyfill -->
<!-- Remove this when import maps will be widely supported -->
<script async src="https://unpkg.com/es-module-shims@1.3.6/dist/es-module-shims.js"></script>
<script type="importmap">
{
"imports": {
"three": "../../build/three.module.js",
"three/addons/": "../../examples/jsm/"
}
}
</script>
<script type="module">
import * as THREE from 'three';
import {OrbitControls} from 'three/addons/controls/OrbitControls.js';
function main() {
const canvas = document.querySelector('#c');
const renderer = new THREE.WebGLRenderer({canvas});
const fov = 75;
const aspect = 2; // the canvas default
const near = 0.1;
const far = 1000;
const camera = new THREE.PerspectiveCamera(fov, aspect, near, far);
camera.position.set(0, 2, 5);
const controls = new OrbitControls(camera, canvas);
controls.target.set(0, 2, 0);
controls.minPolarAngle = 0;
controls.maxPolarAngle = Math.PI / 2;
controls.update();
const scene = new THREE.Scene();
function addLight(position) {
const color = 0xFFFFFF;
const intensity = 1;
const light = new THREE.DirectionalLight(color, intensity);
light.position.set(...position);
scene.add(light);
scene.add(light.target);
}
addLight([-3, 1, 1]);
addLight([ 2, 1, .5]);
const trunkRadius = .2;
const trunkHeight = 1;
const trunkRadialSegments = 12;
const trunkGeometry = new THREE.CylinderGeometry(
trunkRadius, trunkRadius, trunkHeight, trunkRadialSegments);
const topRadius = trunkRadius * 4;
const topHeight = trunkHeight * 2;
const topSegments = 12;
const topGeometry = new THREE.ConeGeometry(
topRadius, topHeight, topSegments);
const trunkMaterial = new THREE.MeshPhongMaterial({color: 'brown'});
const topMaterial = new THREE.MeshPhongMaterial({color: 'green'});
function makeTree(x, z) {
const root = new THREE.Object3D();
const trunk = new THREE.Mesh(trunkGeometry, trunkMaterial);
trunk.position.y = trunkHeight / 2;
root.add(trunk);
const top = new THREE.Mesh(topGeometry, topMaterial);
top.position.y = trunkHeight + topHeight / 2;
root.add(top);
root.position.set(x, 0, z);
scene.add(root);
return root;
}
function frameArea(sizeToFitOnScreen, boxSize, boxCenter, camera) {
const halfSizeToFitOnScreen = sizeToFitOnScreen * 0.5;
const halfFovY = THREE.MathUtils.degToRad(camera.fov * .5);
const distance = halfSizeToFitOnScreen / Math.tan(halfFovY);
camera.position.copy(boxCenter);
camera.position.z += distance;
// pick some near and far values for the frustum that
// will contain the box.
camera.near = boxSize / 100;
camera.far = boxSize * 100;
camera.updateProjectionMatrix();
}
function makeSpriteTexture(textureSize, obj) {
const rt = new THREE.WebGLRenderTarget(textureSize, textureSize);
const aspect = 1; // because the render target is square
const camera = new THREE.PerspectiveCamera(fov, aspect, near, far);
scene.add(obj);
// compute the box that contains obj
const box = new THREE.Box3().setFromObject(obj);
const boxSize = box.getSize(new THREE.Vector3());
const boxCenter = box.getCenter(new THREE.Vector3());
// set the camera to frame the box
const fudge = 1.1;
const size = Math.max(...boxSize.toArray()) * fudge;
frameArea(size, size, boxCenter, camera);
renderer.autoClear = false;
renderer.setRenderTarget(rt);
renderer.render(scene, camera);
renderer.setRenderTarget(null);
renderer.autoClear = true;
scene.remove(obj);
return {
offset: boxCenter.multiplyScalar(fudge),
scale: size,
texture: rt.texture,
};
}
// make billboard texture
const tree = makeTree(0, 0);
const facadeSize = 64;
const treeSpriteInfo = makeSpriteTexture(facadeSize, tree);
function makeSprite(spriteInfo, x, z) {
const {texture, offset, scale} = spriteInfo;
const mat = new THREE.SpriteMaterial({
map: texture,
transparent: true,
});
const sprite = new THREE.Sprite(mat);
scene.add(sprite);
sprite.position.set(
offset.x + x,
offset.y,
offset.z + z);
sprite.scale.set(scale, scale, scale);
}
for (let z = -50; z <= 50; z += 10) {
for (let x = -50; x <= 50; x += 10) {
makeSprite(treeSpriteInfo, x, z);
}
}
scene.background = new THREE.Color('lightblue');
{
const size = 400;
const geometry = new THREE.PlaneGeometry(size, size);
const material = new THREE.MeshPhongMaterial({color: 'gray'});
const mesh = new THREE.Mesh(geometry, material);
mesh.rotation.x = Math.PI * -0.5;
scene.add(mesh);
}
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;
}
function render() {
if (resizeRendererToDisplaySize(renderer)) {
const canvas = renderer.domElement;
camera.aspect = canvas.clientWidth / canvas.clientHeight;
camera.updateProjectionMatrix();
}
renderer.render(scene, camera);
requestAnimationFrame(render);
}
requestAnimationFrame(render);
}
main();
</script>
</html>