Three.js开发指南---学习使用几何体(第五章)

时间:2021-10-25 04:21:56

 

一 基础几何体

  1 二维图形:二维图形都是基于x和y轴构建的,即展示的形式就是他们都是“直立”的,如果希望这些二维图形躺下,则需要将几何体沿着x轴向后旋转1/4圈

mesh.rotation.x=-Math.PI/2;

Three.js开发指南---学习使用几何体(第五章)

 

  1.1 PlaneGeometry:平面几何体 new THREE.PlaneGeometry(width,height,widthSegments,heightSegments)

<!DOCTYPE html>

<html>

<head>
<title>Example 05.01 - Basic 2D geometries - Plane</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

//var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

//宽 高,宽度分为几段,长度分为几段
var plane = createMesh(new THREE.PlaneGeometry(10, 14, 4, 4));
// add the sphere to the scene
scene.add(plane);

// position and point the camera to the center of the scene
camera.position.x = -20;
camera.position.y
= 30;
camera.position.z
= 40;
camera.lookAt(
new THREE.Vector3(10, 0, 0));


// add spotlight for the shadows
var spotLight = new THREE.SpotLight(0xffffff);
spotLight.position.set(
-40, 60, -10);
scene.add(spotLight);

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {
// we need the first child, since it's a multimaterial

//初始控制器的宽和高展示的是上面我们new THREE.Plane的宽和高
//所以我们使用对象plane来获取其宽和高以及宽度的段数和高度的段数
this.width = plane.children[0].geometry.parameters.width;
this.height = plane.children[0].geometry.parameters.height;

this.widthSegments = plane.children[0].geometry.parameters.widthSegments;
this.heightSegments = plane.children[0].geometry.parameters.heightSegments;

this.redraw = function () {
// remove the old plane
scene.remove(plane);
// create a new one
plane = createMesh(new THREE.PlaneGeometry(controls.width, controls.height, Math.round(controls.widthSegments), Math.round(controls.heightSegments)));
// add it to the scene.
scene.add(plane);
};
};

var gui = new dat.GUI();
gui.add(controls,
'width', 0, 40).onChange(controls.redraw);
gui.add(controls,
'height', 0, 40).onChange(controls.redraw);
gui.add(controls,
'widthSegments', 0, 10).onChange(controls.redraw);
gui.add(controls,
'heightSegments', 0, 10).onChange(controls.redraw);
render();

function createMesh(geom) {

// 生成一个法向量材质
var meshMaterial = new THREE.MeshNormalMaterial();
//几何体的两面都应用该材质
meshMaterial.side = THREE.DoubleSide;
//生成一个基础材质,即赋予几何体一种简单的颜色或者线框
var wireFrameMat = new THREE.MeshBasicMaterial();
//看来基础材质在此处的作用是线框
wireFrameMat.wireframe = true;

// create a multimaterial
//一种几何体应用多种材质THREE.SceneUtils.createMultiMaterialObject
var plane = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

return plane;
}

function render() {
//stats.update();

plane.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}


}
window.onload
= init;
</script>
</body>
</html>

 

 

1.2 CircleGeometry:二维圆/部分圆:new THREE.CircleGeometry(radius,segment,thetaStart开始角度,thetaLength角度)

 

<!DOCTYPE html>

<html>

<head>
<title>Example 05.02 - Basic 2D geometries - Circle</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

var circle = createMesh(new THREE.CircleGeometry(4, 10, 0, Math.PI * 2));
// add the sphere to the scene
scene.add(circle);

// position and point the camera to the center of the scene
camera.position.x = -20;
camera.position.y
= 30;
camera.position.z
= 40;
camera.lookAt(
new THREE.Vector3(10, 0, 0));


// add spotlight for the shadows
var spotLight = new THREE.SpotLight(0xffffff);
spotLight.position.set(
-40, 60, -10);
scene.add(spotLight);

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {
// we need the first child, since it's a multimaterial


//console.log(circle.children[0].geometry);
this.radius =circle.children[0].geometry.parameters.radius;

this.thetaStart =circle.children[0].geometry.parameters.thetaStart;
this.thetaLength =circle.children[0].geometry.parameters.thetaLength;
this.segments =circle.children[0].geometry.parameters.segments;

this.redraw = function () {
// remove the old plane
scene.remove(circle);
// create a new one
circle = createMesh(new THREE.CircleGeometry(controls.radius, controls.segments, controls.thetaStart, controls.thetaLength));
// add it to the scene.

scene.add(circle);
};
};

var gui = new dat.GUI();
gui.add(controls,
'radius', 0, 40).onChange(controls.redraw);
gui.add(controls,
'segments', 0, 40).onChange(controls.redraw);
gui.add(controls,
'thetaStart', 0, 2 * Math.PI).onChange(controls.redraw);
gui.add(controls,
'thetaLength', 0, 2 * Math.PI).onChange(controls.redraw);
render();

function createMesh(geom) {

// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial();
meshMaterial.side
= THREE.DoubleSide;
var wireFrameMat = new THREE.MeshBasicMaterial();
wireFrameMat.wireframe
= true;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

//将该二维圆形“放倒”
mesh.rotation.x=-Math.PI/2
return mesh;
}

function render() {
stats.update();

circle.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}

function initStats() {

var stats = new Stats();
stats.setMode(
0); // 0: fps, 1: ms

// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left
= '0px';
stats.domElement.style.top
= '0px';

document.getElementById(
"Stats-output").appendChild(stats.domElement);

return stats;
}
}
window.onload
= init;
</script>
</body>
</html>

 

  1.3 塑形平面:ShapeGeometry

   使用ShapeGeometry定制图形,必须使用shape的绘制函数,下面我们先介绍一下绘制函数

Shape对象(注意与ShapGeometry对象的区别)的绘图函数

函数名称 描述
moveTo 将绘图点移动到某个位置
lineTo /从当前位置绘制一条直线到指定的x,y处
quadraticCurveTo(acPx,acPy) 二次曲线
bezierCurveTo(acPx1,acPy1,acPx2,acPy2,x,y) 贝塞尔曲线Three.js开发指南---学习使用几何体(第五章)

 

 splineThru(数组集合)  沿着所给定的点,绘制一条光滑的曲线,参数是一个THREE.Vector2的数组

 arc(ax,ay,aRdius,aStartAngle,aEndAngle,aClockwise)

 ax,ay用来指定圆心与当前位置之间的偏移量,

aRadius半径,

aStartAngle,aEndAngle开始与结束的弧长,

以及aClockwise顺/逆时针

 makeGeometry 该函数从Shape对象返回一个ShapeGeometry对象
  createPointsGeometry(divisions)

将图形转换为一个点集,参数为返回点的数量,该值越高,返回的点越多,再次绘制图形时曲线越光滑

参数divisions会分别应用到路径的每一个部分

   createSpacedPointsGeometry(divisions)  与createPointsGeometry函数功能相同,但是该方法的参数会一次性的应用到整个路径上

 

 

<!DOCTYPE html>

<html>

<head>
<title>Example 05.03 - Basic 2D geometries - Shape</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;
var shape=drawShape();//此处返回的是Shape对象
var shapeGeo=new THREE.ShapeGeometry(shape);//Shape对象是作为参数传递给ShapeGeometry对象的构造函数的
var shapeMesh = createMesh(shapeGeo);//几何体与材质相结合生成一个网格
// add the sphere to the scene
scene.add(shapeMesh);//将网格追加到场景中

// position and point the camera to the center of the scene
camera.position.x = -30;
camera.position.y
= 70;
camera.position.z
= 70;
camera.lookAt(
new THREE.Vector3(10, 0, 0));


// add spotlight for the shadows
var spotLight = new THREE.SpotLight(0xffffff);
spotLight.position.set(
-40, 60, -10);
scene.add(spotLight);

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {

this.asGeom = function () {
// remove the old plane
scene.remove(shapeMesh);
// create a new one
      //注意shape,shapGeometry的关系
var shape=drawShape();
var shapeGeo=new THREE.ShapeGeometry(shape);
shapeMesh
= createMesh(shapeGeo);
// add it to the scene.
scene.add(shapeMesh);
};

this.asPoints = function () {
// remove the old plane
scene.remove(shapeMesh);
// create a new one
var
shapeMesh
= createLine(drawShape(), false);
// add it to the scene.
scene.add(shapeMesh);
};

this.asSpacedPoints = function () {
// remove the old plane
scene.remove(shapeMesh);
// create a new one
shapeMesh = createLine(drawShape(), true);
// add it to the scene.
scene.add(shapeMesh);
};
};

var gui = new dat.GUI();
gui.add(controls,
'asGeom');
gui.add(controls,
'asPoints');
gui.add(controls,
'asSpacedPoints');


render();

function drawShape() {

// create a basic shape
var shape = new THREE.Shape();

// startpoint开始的点
shape.moveTo(10, 10);

// straight line upwards 沿着开始点画直线
shape.lineTo(10, 40);

// the top of the figure, curve to the right 绘制贝塞尔曲线
shape.bezierCurveTo(15, 25, 25, 25, 30, 40);

// spline back down 沿着所提供的坐标集合绘制一条光滑的曲线,起始点是当前所在的位置
shape.splineThru(
[
new THREE.Vector2(32, 30),
new THREE.Vector2(28, 20),
new THREE.Vector2(30, 10),
]);

// curve at the bottom,绘制二次曲线
shape.quadraticCurveTo(20, 15, 10, 10);

// add 'eye' hole one
var hole1 = new THREE.Path();
//绘制圆弧
hole1.absellipse(16, 24, 2, 3, 0, Math.PI * 2, true);
shape.holes.push(hole1);

// add 'eye hole 2'
var hole2 = new THREE.Path();
hole2.absellipse(
23, 24, 2, 3, 0, Math.PI * 2, true);
shape.holes.push(hole2);

// add 'mouth'
var hole3 = new THREE.Path();
hole3.absarc(
20, 16, 2, 0, Math.PI, true);
shape.holes.push(hole3);

//Shape对象的makeGeometry方法,用于返回一个几何体
console.log(shape.makeGeometry());
return shape;
}

function createMesh(geom) {
//console.log(geom);
// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial();
meshMaterial.side
= THREE.DoubleSide;
var wireFrameMat = new THREE.MeshBasicMaterial();
wireFrameMat.wireframe
= true;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

return mesh;
}

function createLine(shape, spaced) {
console.log(shape);
if (!spaced) {

var mesh = new THREE.Line(shape.createPointsGeometry(10), new THREE.LineBasicMaterial({
color:
0xff3333,
linewidth:
2
}));
return mesh;
}
else {
//three.js的该方法错误createSpacedPointsGeometry
var points=shape.createSpacedPointsGeometry(3);
var mesh = new THREE.Line(points, new THREE.LineBasicMaterial({
color:
0xff3333,
linewidth:
2
}));
return mesh;
}

}

function render() {
//stats.update();

shapeMesh.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}
}
window.onload
= init;
</script>
</body>
</html>

 

 二、三维几何体

  2.1 BoxGeometry:立方体 new THREE.BoxGeometry(width,height,depth,widthSegements,heightSegements,depthSegements)

<!DOCTYPE html>

<html>

<head>
<title>Example 05.04 - Basic 2D geometries - Cube</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

var cube = createMesh(new THREE.BoxGeometry(10, 10, 10, 1, 1, 1));
// add the sphere to the scene
scene.add(cube);

// position and point the camera to the center of the scene
camera.position.x = -20;
camera.position.y
= 30;
camera.position.z
= 40;
camera.lookAt(
new THREE.Vector3(10, 0, 0));


// add spotlight for the shadows
var spotLight = new THREE.SpotLight(0xffffff);
spotLight.position.set(
-40, 60, -10);
scene.add(spotLight);

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {

this.width = cube.children[0].geometry.parameters.width;
this.height = cube.children[0].geometry.parameters.height;
this.depth = cube.children[0].geometry.parameters.depth;

this.widthSegments = cube.children[0].geometry.parameters.widthSegments;
this.heightSegments = cube.children[0].geometry.parameters.heightSegments;
this.depthSegments = cube.children[0].geometry.parameters.depthSegments;


this.redraw = function () {
// remove the old plane
scene.remove(cube);
// create a new one
cube = createMesh(new THREE.BoxGeometry(controls.width, controls.height, controls.depth, Math.round(controls.widthSegments), Math.round(controls.heightSegments), Math.round(controls.depthSegments)));
// add it to the scene.
scene.add(cube);
};
};

var gui = new dat.GUI();
gui.add(controls,
'width', 0, 40).onChange(controls.redraw);
gui.add(controls,
'height', 0, 40).onChange(controls.redraw);
gui.add(controls,
'depth', 0, 40).onChange(controls.redraw);
gui.add(controls,
'widthSegments', 0, 10).onChange(controls.redraw);
gui.add(controls,
'heightSegments', 0, 10).onChange(controls.redraw);
gui.add(controls,
'depthSegments', 0, 10).onChange(controls.redraw);
render();

function createMesh(geom) {

// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial();
meshMaterial.side
= THREE.DoubleSide;
var wireFrameMat = new THREE.MeshBasicMaterial();
wireFrameMat.wireframe
= true;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

return mesh;
}

function render() {
stats.update();

cube.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}

function initStats() {

var stats = new Stats();
stats.setMode(
0); // 0: fps, 1: ms

// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left
= '0px';
stats.domElement.style.top
= '0px';

document.getElementById(
"Stats-output").appendChild(stats.domElement);

return stats;
}
}
window.onload
= init;
</script>
</body>
</html>

 

  2.2 SphereGeometry球体

  参数:radius半径,

    widthSegements竖直方向分段,

    heightSegments水平方向分段,

    phiStart从x轴的什么地方开始绘制0-2*pi,

    phiLength绘制多少弧度,

    thetaStart从y轴的什么地方开始绘制,

    thetaLength绘制多少弧度

 

<!DOCTYPE html>

<html>

<head>
<title>Example 05.05 - Basic 3D geometries - Sphere</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

var sphere = createMesh(new THREE.SphereGeometry(4, 10, 10));
// add the sphere to the scene
scene.add(sphere);

// position and point the camera to the center of the scene
camera.position.x = -20;
camera.position.y
= 30;
camera.position.z
= 40;
camera.lookAt(
new THREE.Vector3(10, 0, 0));


// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {
// we need the first child, since it's a multimaterial
this.radius = sphere.children[0].geometry.parameters.radius;
this.widthSegments = sphere.children[0].geometry.parameters.widthSegments;
this.heightSegments = sphere.children[0].geometry.parameters.heightSegments;
this.phiStart = 0;
this.phiLength = Math.PI * 2;
this.thetaStart = 0;
this.thetaLength = Math.PI;


this.redraw = function () {
// remove the old plane
scene.remove(sphere);
// create a new one
          var r=controls.radius;
          var ws=controls.widthSegments;
          var hs= controls.heightSegments;
var ps=controls.phiStart;
var pl=controls.phiLength;
var ts=controls.thetaStart;
var tl=controls.thetaLength

          var geo=new THREE.SphereGeometry(r, ws,hs , ps,pl , ts,tl )
sphere = createMesh(geo);
// add it to the scene.
scene.add(sphere);
};
};

var gui = new dat.GUI();
gui.add(controls,
'radius', 0, 40).onChange(controls.redraw);
gui.add(controls,
'widthSegments', 0, 20).onChange(controls.redraw);
gui.add(controls,
'heightSegments', 0, 20).onChange(controls.redraw);
gui.add(controls,
'phiStart', 0, 2 * Math.PI).onChange(controls.redraw);
gui.add(controls,
'phiLength', 0, 2 * Math.PI).onChange(controls.redraw);
gui.add(controls,
'thetaStart', 0, 2 * Math.PI).onChange(controls.redraw);
gui.add(controls,
'thetaLength', 0, 2 * Math.PI).onChange(controls.redraw);


render();

function createMesh(geom) {

// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial();
meshMaterial.side
= THREE.DoubleSide;
var wireFrameMat = new THREE.MeshBasicMaterial();
wireFrameMat.wireframe
= true;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

return mesh;
}

function render() {
stats.update();

sphere.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}

function initStats() {

var stats = new Stats();
stats.setMode(
0); // 0: fps, 1: ms

// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left
= '0px';
stats.domElement.style.top
= '0px';

document.getElementById(
"Stats-output").appendChild(stats.domElement);

return stats;
}
}
window.onload
= init;
</script>
</body>
</html>

 

 

Three.js开发指南---学习使用几何体(第五章)

  2.3 CylinderGeometry:构建圆柱体

  参数:radiusTop:圆柱顶部的半径

      radiusBottom:圆柱底部的半径

      height:圆柱体的高度

      segmentsX:沿x轴,即竖向分割为多少段

    segmentsY:沿Y轴,即横向分割为多少段

    openEnded:网格顶部和底部是否封闭

<!DOCTYPE html>

<html>

<head>
<title>Example 05.07 - Basic 3D geometries - Cylinder</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

var cylinder = createMesh(new THREE.CylinderGeometry(20, 20, 20));
// add the sphere to the scene
scene.add(cylinder);

// position and point the camera to the center of the scene
camera.position.x = -30;
camera.position.y
= 40;
camera.position.z
= 50;
camera.lookAt(
new THREE.Vector3(10, 0, 0));

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {
// we need the first child, since it's a multimaterial

this.radiusTop = 20;
this.radiusBottom = 20;
this.height = 20;

this.radialSegments = 8;
this.heightSegments = 8;

this.openEnded = false;

this.redraw = function () {
// remove the old plane
scene.remove(cylinder);
// create a new one
var rt=controls.radiusTop;//圆柱顶部的半径,可以为负数
var rb=controls.radiusBottom;//圆柱底部的半径
var h=controls.height;//圆柱体的高度
var rs=controls.radialSegments;//圆柱体竖向的段数
var hs=controls.heightSegments;//圆柱体横向的段数
var oe=controls.openEnded;//圆柱体的底部和顶部是否封闭
cylinder = createMesh(new THREE.CylinderGeometry(rt, rb, h,rs , hs,oe ));
// add it to the scene.
scene.add(cylinder);
};
};

var gui = new dat.GUI();
gui.add(controls,
'radiusTop', -40, 40).onChange(controls.redraw);
gui.add(controls,
'radiusBottom', -40, 40).onChange(controls.redraw);
gui.add(controls,
'height', 0, 40).onChange(controls.redraw);
gui.add(controls,
'radialSegments', 1, 20).step(1).onChange(controls.redraw);
gui.add(controls,
'heightSegments', 1, 20).step(1).onChange(controls.redraw);
gui.add(controls,
'openEnded').onChange(controls.redraw);


render();

function createMesh(geom) {

// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial();
meshMaterial.side
= THREE.DoubleSide;
var wireFrameMat = new THREE.MeshBasicMaterial();
wireFrameMat.wireframe
= true;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

return mesh;
}

function render() {
stats.update();

cylinder.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}

function initStats() {

var stats = new Stats();
stats.setMode(
0); // 0: fps, 1: ms

// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left
= '0px';
stats.domElement.style.top
= '0px';

document.getElementById(
"Stats-output").appendChild(stats.domElement);

return stats;
}
}
window.onload
= init;
</script>
</body>
</html>

 

 Three.js开发指南---学习使用几何体(第五章)

  2.4 圆环RingGeometry:类似于甜甜圈

  参数:radius:半径,整个圆环的半径

    tube:圆环的半径,注意与radius的区别

    radialSegments:沿圆环长度方向分割的段数

    tubularSegments:沿圆环宽度方向分割的段数

    arc:绘制多少圆环,即是否为2*pi

 

Three.js开发指南---学习使用几何体(第五章)

<!DOCTYPE html>

<html>

<head>
<title>Example 05.09 - Basic 3D geometries - Ring</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

var torus = createMesh(new THREE.RingGeometry());
// add the sphere to the scene
scene.add(torus);

// position and point the camera to the center of the scene
camera.position.x = -30;
camera.position.y
= 40;
camera.position.z
= 50;
camera.lookAt(
new THREE.Vector3(10, 0, 0));

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {
// we need the first child, since it's a multimaterial

this.innerRadius = 0;
this.outerRadius = 50;
this.thetaSegments = 8;
this.phiSegments = 8;
this.thetaStart = 0;
this.thetaLength = Math.PI * 2;

this.redraw = function () {
// remove the old plane
scene.remove(torus);
// create a new one
var ir=controls.innerRadius;
var or=controls.outerRadius;
var tseg=controls.thetaSegments;
var ps=controls.phiSegments;
var ts=controls.thetaStart;
var tl=controls.thetaLength;
torus
= createMesh(new THREE.RingGeometry(ir,or ,tseg ,ps , ts, tl));
// add it to the scene.
scene.add(torus);
};
};

var gui = new dat.GUI();
gui.add(controls,
'innerRadius', 0, 40).onChange(controls.redraw);
gui.add(controls,
'outerRadius', 0, 100).onChange(controls.redraw);
gui.add(controls,
'thetaSegments', 1, 40).step(1).onChange(controls.redraw);
gui.add(controls,
'phiSegments', 1, 20).step(1).onChange(controls.redraw);
gui.add(controls,
'thetaStart', 0, Math.PI * 2).onChange(controls.redraw);
gui.add(controls,
'thetaLength', 0, Math.PI * 2).onChange(controls.redraw);


render();

function createMesh(geom) {

// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial();
meshMaterial.side
= THREE.DoubleSide;
var wireFrameMat = new THREE.MeshBasicMaterial();
wireFrameMat.wireframe
= true;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

return mesh;
}

function render() {
stats.update();

torus.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}

function initStats() {

var stats = new Stats();
stats.setMode(
0); // 0: fps, 1: ms

// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left
= '0px';
stats.domElement.style.top
= '0px';

document.getElementById(
"Stats-output").appendChild(stats.domElement);

return stats;
}
}
window.onload
= init;
</script>
</body>
</html>

 

  2.5 TorusKnotGeometry环面纽结

  参数:radius:半径

    tube:环的实际半径

    radialSegments:沿圆环长度方向分割的段数

    tubularSegments:沿圆环宽度方向分割的段数

    p:多久旋转一次

    q:绕其内部旋转多少次

    heightScale:通过该属性可以拉伸环面纽结

 Three.js开发指南---学习使用几何体(第五章)

<!DOCTYPE html>

<html>

<head>
<title>Example 05.08 - Basic 3D geometries - Torusknot</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

var knot = createMesh(new THREE.TorusKnotGeometry(10, 1, 64, 8, 2, 3, 1));
// add the sphere to the scene
scene.add(knot);

// position and point the camera to the center of the scene
camera.position.x = -30;
camera.position.y
= 40;
camera.position.z
= 50;
camera.lookAt(
new THREE.Vector3(10, 0, 0));

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {
// we need the first child, since it's a multimaterial
this.radius = knot.children[0].geometry.parameters.radius;
this.tube = 0.3;
this.radialSegments = knot.children[0].geometry.parameters.radialSegments;
this.tubularSegments = knot.children[0].geometry.parameters.tubularSegments;
this.p = knot.children[0].geometry.parameters.p;
this.q = knot.children[0].geometry.parameters.q;
this.heightScale = knot.children[0].geometry.parameters.heightScale;

this.redraw = function () {
// remove the old plane
scene.remove(knot);
// create a new one
var r=controls.radius;
var t=controls.tube;
var rs=Math.round(controls.radialSegments);
var ts=Math.round(controls.tubularSegments);
var p=Math.round(controls.p);
var q=Math.round(controls.q);
var hs=controls.heightScale;
knot
= createMesh(new THREE.TorusKnotGeometry(r,t , rs, ts, p,q ,hs ));
// add it to the scene.
scene.add(knot);
};
};

var gui = new dat.GUI();
gui.add(controls,
'radius', 0, 40).onChange(controls.redraw);
gui.add(controls,
'tube', 0, 40).onChange(controls.redraw);
gui.add(controls,
'radialSegments', 0, 400).step(1).onChange(controls.redraw);
gui.add(controls,
'tubularSegments', 1, 20).step(1).onChange(controls.redraw);
gui.add(controls,
'p', 1, 10).step(1).onChange(controls.redraw);
gui.add(controls,
'q', 1, 15).step(1).onChange(controls.redraw);
gui.add(controls,
'heightScale', 0, 5).onChange(controls.redraw);


render();

function createMesh(geom) {

// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial({});
meshMaterial.side
= THREE.DoubleSide;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial]);

return mesh;
}

function render() {
stats.update();

knot.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}

function initStats() {

var stats = new Stats();
stats.setMode(
0); // 0: fps, 1: ms

// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left
= '0px';
stats.domElement.style.top
= '0px';

document.getElementById(
"Stats-output").appendChild(stats.domElement);

return stats;
}
}
window.onload
= init;
</script>
</body>
</html>

 

  2.6 多面体PolyhedronGeometry

  参数:vertices顶点

  faces:面

  radius:多面体的半径,即大小,这里只是缩放,并不是真的改变坐标

  detail:当该值为1时,x面体的每个面分割为x个面体,当参数为2时,在参数为1的基础上,再次将各个面分割为x面体,依次类推

  Three.js开发指南---学习使用几何体(第五章)Three.js开发指南---学习使用几何体(第五章)

<!DOCTYPE html>

<html>

<head>
<title>Example 05.09 - Basic 3D geometries - Polyhedron</title>
<script type="text/javascript" src="../libs/three.js"></script>

<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body
{
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin
: 0;
overflow
: hidden;
}
</style>
</head>
<body>

<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>

<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">

// once everything is loaded, we run our Three.js stuff.
function init() {

var stats = initStats();

// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();

// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);

// create a render and set the size
var webGLRenderer = new THREE.WebGLRenderer();
webGLRenderer.setClearColor(
new THREE.Color(0xEEEEEE, 1.0));
webGLRenderer.setSize(window.innerWidth, window.innerHeight);
webGLRenderer.shadowMapEnabled
= true;

var polyhedron = createMesh(new THREE.IcosahedronGeometry(10, 0));
// add the sphere to the scene
scene.add(polyhedron);

// position and point the camera to the center of the scene
camera.position.x = -30;
camera.position.y
= 40;
camera.position.z
= 50;
camera.lookAt(
new THREE.Vector3(10, 0, 0));

// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(webGLRenderer.domElement);

// call the render function
var step = 0;


// setup the control gui
var controls = new function () {
// we need the first child, since it's a multimaterial
this.radius = 10;
this.detail = 0;
this.type = 'Icosahedron';


this.redraw = function () {
// remove the old plane
scene.remove(polyhedron);
// create a new one

switch (controls.type) {
case 'Icosahedron':
//正20面体
polyhedron = createMesh(new THREE.IcosahedronGeometry(controls.radius, controls.detail));
break;
case 'Tetrahedron':
//正四面体
polyhedron = createMesh(new THREE.TetrahedronGeometry(controls.radius, controls.detail));
break;
case 'Octahedron':
//正八面体
polyhedron = createMesh(new THREE.OctahedronGeometry(controls.radius, controls.detail));
break;
case 'Dodecahedron':
//正十二面体
polyhedron = createMesh(new THREE.DodecahedronGeometry(controls.radius, controls.detail));
break;
case 'Custom':
var vertices = [
1, 1, 1, -1, -1, 1, -1, 1, -1, 1, -1, -1
];

var indices = [
2, 1, 0, 0, 3, 2, 1, 3, 0, 2, 3, 1
];

polyhedron
= createMesh(new THREE.PolyhedronGeometry(vertices, indices, controls.radius, controls.detail));
break;
}

// add it to the scene.
scene.add(polyhedron);
};
};

var gui = new dat.GUI();
gui.add(controls,
'radius', 0, 40).step(1).onChange(controls.redraw);
gui.add(controls,
'detail', 0, 3).step(1).onChange(controls.redraw);
gui.add(controls,
'type', ['Icosahedron', 'Tetrahedron', 'Octahedron', 'Dodecahedron', 'Custom']).onChange(controls.redraw);


render();

function createMesh(geom) {

// assign two materials
var meshMaterial = new THREE.MeshNormalMaterial();
meshMaterial.side
= THREE.DoubleSide;
var wireFrameMat = new THREE.MeshBasicMaterial();
wireFrameMat.wireframe
= true;

// create a multimaterial
var mesh = THREE.SceneUtils.createMultiMaterialObject(geom, [meshMaterial, wireFrameMat]);

return mesh;
}

function render() {
stats.update();

polyhedron.rotation.y
= step += 0.01;

// render using requestAnimationFrame
requestAnimationFrame(render);
webGLRenderer.render(scene, camera);
}

function initStats() {

var stats = new Stats();
stats.setMode(
0); // 0: fps, 1: ms

// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left
= '0px';
stats.domElement.style.top
= '0px';

document.getElementById(
"Stats-output").appendChild(stats.domElement);

return stats;
}
}
window.onload
= init;
</script>
</body>
</html>