纳金网

标题: Sandy3D应用指南——使用灯光 [打印本页]

作者: 驰骋的风 时间: 2012-9-25 11:23
标题: Sandy3D应用指南——使用灯光
指南目标
在这个指南里，我们决定展示Sandy关于灯光的功能。当你想使用每个对象的内置的灯光效果来渲染你的对象时。你可能满足于默认的设置，但你也可能希望可以修改灯光的强度或灯光的方向。在这里你将会学到怎么实现这些。

怎么做？
代码如下：

package {

import flash.display.Sprite;

import flash.events.*;

import flash.ui.*;

import sandy.core.Scene3D;

import sandy.core.data.*;

import sandy.core.scenegraph.*;

import sandy.materials.*;

import sandy.materials.attributes.*;

import sandy.primitive.*;

public class Example0041 extends Sprite {

   private var scene:Scene3D;

   private var camera:Camera3D;

   private var tg:TransformGroup;

   private var lightX = 0;

   private var lightY = 0;

   private var lightZ = 10;

   public function Example0041() {

      camera = new Camera3D( 300, 300 );

      camera.z = -400;

      var root:Group = createScene();

      scene = new Scene3D( "scene", this, camera, root );

      scene.light.setDirection(lightX, lightY, lightZ);

      addEventListener( Event.ENTER_FRAME, enterFrameHandler );

      stage.addEventListener(KeyboardEvent.KEY_DOWN, keyPressed);

   }

   private function createScene():Group {

      var g:Group = new Group();

      tg = new TransformGroup();

      var materialAttr:MaterialAttributes = new MaterialAttributes(

                        new LineAttributes( 0, 0x2111BB, 0 ),
new LightAttributes( ***e, 0.1)

                     );

      var material:Material = new ColorMaterial( 0xFFCC33, 1, materialAttr );

      material.lightingEnable = ***e;

      var app:Appearance = new Appearance( material );

      var materialAttr2:MaterialAttributes = new MaterialAttributes(

                        new LineAttributes( 0, 0x2111BB, 0 ),

                        new LightAttributes( ***e, 0.1)

                     );

      var material2:Material = new ColorMaterial( 0xCC0000, 1, materialAttr );

      material2.lightingEnable = ***e;

      var app2:Appearance = new Appearance( material2 );

      var materialAttr3:MaterialAttributes = new MaterialAttributes(

                        new LineAttributes( 0, 0x2111BB, 0 ),

                        new LightAttributes( ***e, 0.1)

                     );

      var material3:Material = new ColorMaterial( 0x008AE6, 1, materialAttr );

      material3.lightingEnable = ***e;

      var app3:Appearance = new Appearance( material3 );

      var table = new Box( "table", 10, 150, 200, PrimitiveMode.QUAD, 1 );

      //table.enableBackFaceCulling = false;

      table.useSingleContainer = false;

      table.appearance = app;

      table.rotateY = 90;

      table.rotateX = 90;

      var leg01:Cylinder = new Cylinder( "leg01", 5, 80 );

      leg01.appearance = app;

      leg01.x = -80;

      leg01.y = -45;

      leg01.z = 50;

      var leg02:Cylinder = new Cylinder( "leg02", 5, 80 );

      leg02.appearance = app;

      leg02.x = 80;

      leg02.y = -45;

      leg02.z = 50;

      var leg03:Cylinder = new Cylinder( "leg02", 5, 80 );

      leg03.appearance = app;

      leg03.x = -80;

      leg03.y = -45;

      leg03.z = -50;

      var leg04:Cylinder = new Cylinder( "leg02", 5, 80 );

      leg04.appearance = app;

      leg04.x = 80;

      leg04.y = -45;

      leg04.z = -50;

      var mySphere:Sphere = new Sphere( "theSphere", 20, 20, 8);

      mySphere.useSingleContainer = ***e;

      mySphere.appearance = app2;

      mySphere.y = 25;

      mySphere.x = -30;

      var myBox:Box = new Box( "theBox", 60, 60, 60, PrimitiveMode.TRI, 3 );

      myBox.useSingleContainer = ***e;

      myBox.appearance = app3;

      myBox.rotateY = 30;

      myBox.y = 35;

      myBox.x = 40;

      tg.addChild(table);

      tg.addChild(leg01);

      tg.addChild(leg02);

      tg.addChild(leg03);

      tg.addChild(leg04);

      tg.addChild(mySphere);

      tg.addChild(myBox);

      tg.rotateX = 5;

      g.addChild( tg );

      return g;

   }

   private function enterFrameHandler( event : Event ) : void {

      scene.render();

   }

   private function keyPressed(event:KeyboardEvent):void {

      switch(event.keyCode) {

         case Keyboard.PAGE_DOWN:

            scene.light.setPower(scene.light.getPower() - 5);

            break;

         case Keyboard.PAGE_UP:

            scene.light.setPower(scene.light.getPower() + 5);

            break;

         case Keyboard.UP:

            lightY+=10;

            scene.light.setDirection(lightX, lightY, lightZ);

            break;

         case Keyboard.DOWN:

            lightY-=10;

            scene.light.setDirection(lightX, lightY, lightZ);

            break;

         case Keyboard.RIGHT:

            lightX+=10;

            scene.light.setDirection(lightX, lightY, lightZ);

            break;

         case Keyboard.LEFT:

            lightX-=10;

            scene.light.setDirection(lightX, lightY, lightZ);

            break;

      }

   }

}

}

让我们看看在代码里做了什么

X,Y,Z变量
因为要控制灯光的方向，所以我们在3D的世界里需要三个变量X，Y，Z，我们把它们高为成员变量。这样我们就可以通过键盘的方向键来控制它们的值了。
private var lightX = 0;

private var lightY = 0;

private var lightZ = 10;

设置灯光的位置
scene.light.setDirection(lightX, lightY, lightZ);

如你所见，你只需获取Scene3D对象的light属性然后调置它的值就可以了。

然后在createScene()方法里，我放入了很多对象来模拟一张台和一个球和一个圆环。这张台是一个Box和四个Cylinder（作为四条腿），还有那个球是一个Sphere对象。我将跳过这部份的代码说明，因为我想在之前的指南中，你能很容易理解这些。

创建输入控制器
现在让我们做最重要的东西就是放在控制函数：keyPressed(event:KeyboardEvent).中的代码：
case Keyboard.PAGE_DOWN:

scene.light.setPower(scene.light.getPower() - 5);

break;

case Keyboard.PAGE_UP:

scene.light.setPower(scene.light.getPower() + 5);

break;

case Keyboard.UP:

lightY+=10;

scene.light.setDirection(lightX, lightY, lightZ);

break;

case Keyboard.DOWN:

lightY-=10;

scene.light.setDirection(lightX, lightY, lightZ);

break;

case Keyboard.RIGHT:

lightX+=10;

scene.light.setDirection(lightX, lightY, lightZ);

break;

case Keyboard.LEFT:

lightX-=10;

scene.light.setDirection(lightX, lightY, lightZ);

break;

使用pageUp和pageDown键可以控制灯光的强度，方向键可以控制灯光的方向。

下面让我们看看最终的效果：

更多分享尽在Web3D纳金网www.narkii.com

作者: kikkik7000 时间: 2014-7-10 10:51
谢谢分享！

欢迎光临纳金网 (http://wwww.narkii.com/club/)