html5的canvas实现3d雪花飘舞效果_html5教程技巧

复制代码代码如下:var SCREEN_WIDTH = window.innerWidth; var SCREEN_HEIGHT = window.innerHeight; var container; var particle; var camera; var scene; var renderer; var mouseX = 0; var mouseY = 0; var windowHalfX = window.innerWidth / 2; var windowHalfY = window.innerHeight / 2; var particles = []; var particleImage = new Image();//THREE.ImageUtils.loadTexture( "img/ParticleSmoke.png" ); particleImage.src = 'images/ParticleSmoke.png'; function init() { container = document.createElement('div'); document.body.appendChild(container); camera = new THREE.PerspectiveCamera( 75, SCREEN_WIDTH / SCREEN_HEIGHT, 1, 10000 ); camera.position.z = 1000; scene = new THREE.Scene(); scene.add(camera); renderer = new THREE.CanvasRenderer(); renderer.setSize(SCREEN_WIDTH, SCREEN_HEIGHT); var material = new THREE.ParticleBasicMaterial( { map: new THREE.Texture(particleImage) } ); for (var i = 0; i particle = new Particle3D( material); particle.position.x = Math.random() * 2000 - 1000; particle.position.y = Math.random() * 2000 - 1000; particle.position.z = Math.random() * 2000 - 1000; particle.scale.x = particle.scale.y = 1; scene.add( particle ); particles.push(particle); } container.appendChild( renderer.domElement ); document.addEventListener( 'mousemove', onDocumentMouseMove, false ); document.addEventListener( 'touchstart', onDocumentTouchStart, false ); document.addEventListener( 'touchmove', onDocumentTouchMove, false ); setInterval( loop, 1000 / 60 ); } function onDocumentMouseMove( event ) { mouseX = event.clientX - windowHalfX; mouseY = event.clientY - windowHalfY; } function onDocumentTouchStart( event ) { if ( event.touches.length == 1 ) { event.preventDefault(); mouseX = event.touches[ 0 ].pageX - windowHalfX; mouseY = event.touches[ 0 ].pageY - windowHalfY; } } function onDocumentTouchMove( event ) { if ( event.touches.length == 1 ) { event.preventDefault(); mouseX = event.touches[ 0 ].pageX - windowHalfX; mouseY = event.touches[ 0 ].pageY - windowHalfY; } } // function loop() { for(var i = 0; i { var particle = particles[i]; particle.updatePhysics(); with(particle.position) { if(y if(x>1000) x-=2000; else if(x if(z>1000) z-=2000; else if(z } } camera.position.x += ( mouseX - camera.position.x ) * 0.05; camera.position.y += ( - mouseY - camera.position.y ) * 0.05; camera.lookAt(scene.position); renderer.render( scene, camera ); }