前幾個星期突然接了小程序的任務,所以three.js的教程就晚點發布了。
直接上代碼,先碼上html和css:
<div id="canvas-frame"></div>
<style>
canvas { width: 100%; height: 100% }
div#canvas-frame {
border: none;
cursor: pointer;
width: 100%;
height: 600px;
background-color: #EEEEEE;
}
</style>
重點在js代碼上:
//重構成規範的模式
var renderer;
function initThree(){
width = document.getElementById('canvas-frame').clientWidth;
height = document.getElementById('canvas-frame').clientHeight;
renderer = new THREE.WebGLRenderer({
antialias:true
});
renderer.setSize(width, height);
document.getElementById('canvas-frame').appendChild(renderer.domElement);
renderer.setClearColor(0xFFFFFF, 1.0);
}
var camera;
function initCamera(){
camera = new THREE.PerspectiveCamera(45,width/height,1,10000);
camera.position.x = 0;
camera.position.y = 1000;
camera.position.z = 0;
camera.up.x = 0;
camera.up.y = 0;
camera.up.z = 1;
camera.lookAt({
x : 0,
y : 0,
z : 0
});
}
var scene;
function initScene(){
scene = new THREE.Scene();
}
var light;
function initLight() {
light = new THREE.DirectionalLight(0xFF0000, 1.0, 0);
light.position.set(100, 100, 200);
scene.add(light);
}
var cube;
function initObject(){
var geometry = new THREE.Geometry();
var material = new THREE.LineBasicMaterial({vertexColors:THREE.VertexColors});
var color1 = new THREE.Color( 0x444444 ), color2 = new THREE.Color( 0xFF0000 );
// 線的材質可以由2點的顏色決定
var p1 = new THREE.Vector3( 100, 0, 100 );
var p2 = new THREE.Vector3( -100, 0, -100 );
geometry.vertices.push(p1);
geometry.vertices.push(p2);
geometry.colors.push( color1, color2 );
//第一個參數是幾何體,第二個參數是材質或者線的屬性,第三個參數是一組點的連接方式
var line = new THREE.Line( geometry, material, THREE.LinePieces );
scene.add(line);
}
function render()
{
renderer.clear();
renderer.render(scene, camera);
requestAnimationFrame(render);
}
function threeStart() {
initThree();
initCamera();
initScene();
initLight();
initObject();
render();
}
window.onload =function(){
threeStart();
}
</script>
renderer,camera和scene是三個重要的組成部分。以上就畫出了線。是不是很easy呢!