Flash 3D physics engine

等候已久的Flash 3D physics Engine出現啦
名稱為：jiglibflash
http://code.google.com/p/jiglibflash/
結合PV3D直接使用, 開心, 不需要再重學。
使用方法也很簡單
在建立PV3D物件後, 再建立對映的Physics物件
如：
new Cube之後
再建立一個JBox來對映
目前支援的碰撞物件有，球體、方塊、Plane。
也支援鏈結的效果。
奶小茶將官方的Demo改寫成自已的Demo。


原始碼：

/*
Example Flash 3D Physics version 0.25 with timestep

Control by   : arrow keys and space bar

3D physics used  : jiglibflash (http://code.google.com/p/jiglibflash/) 
3D renderer used : Papervision 3D (http://code.google.com/p/papervision3d/)
Credits    : Muzer
Demo by    : milkmidi

*/

package
{ 
import flash.display.Sprite;
import flash.display.StageAlign;
import flash.display.StageQuality;
import flash.display.StageScaleMode;
import flash.events.Event; 
import flash.events.MouseEvent;
import flash.utils.getTimer;


import jiglib.geometry.JBox;
import jiglib.geometry.JSphere;
import jiglib.math.JMatrix3D;
import jiglib.math.JNumber3D;
import jiglib.physics.PhysicsSystem;
import jiglib.physics.constraint.JConstraintPoint; 

import org.papervision3d.lights.PointLight3D;
import org.papervision3d.materials.shadematerials.FlatShadeMaterial;
import org.papervision3d.materials.special.ParticleMaterial;
import org.papervision3d.materials.utils.MaterialsList;
import org.papervision3d.objects.DisplayObject3D;
import org.papervision3d.objects.primitives.Cube;
import org.papervision3d.objects.primitives.Sphere;
import org.papervision3d.objects.special.ParticleField;
import org.papervision3d.render.BasicRenderEngine;
import org.papervision3d.scenes.Scene3D;
import org.papervision3d.view.Viewport3D;
import org.papervision3d.view.layer.ViewportLayer;
import org.papervision3d.view.layer.util.ViewportLayerSortMode;
import org.papervision3d.view.stats.StatsView;
import org.papervision3d.materials.ColorMaterial;
import org.papervision3d.view.BasicView;

[SWF(width = "950", height = "500", frameRate = "41", backgroundColor = "#000000", pageTitle = "milkmidi.com")]

public class MyDemo extends BasicView
{
// ------------------------------------------------------------------------
// DECLARE VARIABLES
// ------------------------------------------------------------------------

// Settings
private var amountBalls   : uint = 3; // default 3, amount of balls in the scene the first will be the one you can control with the arrows keys
private var amountBoxes   : uint = 3; // default 3, number of boxes in the scene 
private var amountSphereInChain : uint = 5; // default 5, number of sphere's in the chain
private var speedBall   : int = 50; // defailt 50, speed of the ball which you can control with the arrow keys
private var physicsSpeed  : Number = 5; // default 5, speed * deltatime

private var sceneLight   : PointLight3D;  
private var jBoxArray   : Array = new Array();  



// timer  
private var deltaTime:Number = 0;
private var currentTime:uint;
private var newTime:uint;
private var vplObjects:ViewportLayer;

// ------------------------------------------------------------------------
// MAIN CONSTRUCTOR
// ------------------------------------------------------------------------
public function MyDemo() {


super(0, 0, true, false);
init();
startRendering();
}

// ------------------------------------------------------------------------
// INIT
// ------------------------------------------------------------------------
private function init():void {   
init3DEngine();
initJiglib(); 
init3DObject();
init2DObject();   
createLotOfBox();
}

// ------------------------------------------------------------------------
// SETUP STAGE
// ------------------------------------------------------------------------
private function setupStage():void {
stage.align = StageAlign.TOP_LEFT;  
stage.scaleMode = StageScaleMode.NO_SCALE;   
stage.quality = StageQuality.MEDIUM;
stage.frameRate = 60;  
}


// ------------------------------------------------------------------------
// INIT PAPERVISION 3D 
// ------------------------------------------------------------------------
private function initJiglib():void {
//PhysicsSystem.getInstance().SetSolverType("FAST");
currentTime = getTimer(); // set time for physic loop
}

// ------------------------------------------------------------------------
// INIT PAPERVISION 3D 
// ------------------------------------------------------------------------
private function init3DEngine():void {   
viewport.containerSprite.sortMode = ViewportLayerSortMode.INDEX_SORT; // set viewport sortmode to index    

sceneLight = new PointLight3D(true, true);   
sceneLight.x = 0;
sceneLight.y = 400;
sceneLight.z = -300;

camera.x = 0;
camera.y = 450;
camera.z = -700;
camera.zoom = 10;
camera.focus = 100;  
this.addEventListener(Event.ENTER_FRAME, onEnterFrame);  
}

private function init3DObject():void {
// SETUP GROUND   
var materia1Ground:MaterialsList = new MaterialsList();      
materia1Ground.addMaterial(new FlatShadeMaterial(sceneLight, 0x77ee77), "all");      
var pv3dGround:Cube = new Cube(materia1Ground, 600, 600, 50, 2, 2, 2)      
scene.addChild(pv3dGround);
// Viewport layer ground
var vplGround:ViewportLayer = viewport.getChildLayer(pv3dGround);   
vplGround.layerIndex = 1; // set index to 1
// Ground physics
var jGround:JBox = new JBox(pv3dGround, false, 600, 600, 50);    
PhysicsSystem.getInstance().AddBody(jGround);

// SETUP WALL
var materia1Wall:MaterialsList = new MaterialsList();
materia1Wall.addMaterial(new FlatShadeMaterial(sceneLight, 0x77ee77), "all");
var pv3dWall:Cube = new Cube(materia1Wall, 600, 50, 250);
scene.addChild(pv3dWall);
// viewport layer wall
var vplWall:ViewportLayer = viewport.getChildLayer(pv3dWall);
vplWall.layerIndex = 2; // set index to 1
// Ground physics
var jWall:JBox = new JBox(pv3dWall,false,600,50,250);
jWall.MoveTo(new JNumber3D(0,150,275), JMatrix3D.IDENTITY); // position wall north: y = wall.height/2 + wall.depth/2, z = ground.depth/2 + wall.depth/2  
PhysicsSystem.getInstance().AddBody(jWall);

vplObjects = new ViewportLayer(viewport,null);
vplObjects.layerIndex = 3;
vplObjects.sortMode = ViewportLayerSortMode.Z_SORT; // sort mode for this viewportlayer based on z
viewport.containerSprite.addLayer(vplObjects);
}
private function createLotOfBox():void {
if (jBoxArray.length > 0) {    
for (var i:int = 0; i < jBoxArray.length; i++) {
scene.removeChildByName("cube" + i);
PhysicsSystem.getInstance().RemoveBody(jBoxArray[i]);
}
}
jBoxArray = new Array();


var cube:Cube;
for (i = 0; i < 12; i++) {
var flatMat:FlatShadeMaterial = new FlatShadeMaterial(sceneLight, Math.random() * 0xffffff, 0xffffff);
var ml:MaterialsList = new MaterialsList( { all:flatMat } );
var _scale:Number = Math.random() * 50 + 10;
cube = new Cube(ml, _scale, _scale, _scale);
cube.name = "cube" + i;
vplObjects.addDisplayObject3D(cube);
scene.addChild(cube);

var _jBox:JBox =  new JBox(cube, true, _scale, _scale, _scale);     

var _targetX:Number = Math.random() * 400 - 200;
var _targetY:Number = Math.random() * 500 + 50;
var _targetZ:Number = Math.random() * 400 - 200;
var _position:JNumber3D = new JNumber3D(_targetX, _targetY, _targetZ);
_jBox.MoveTo(_position, JMatrix3D.rotationX(Math.random() * 360 * 180 / Math.PI)); // start position
_jBox.setMass(_scale);

jBoxArray.push(_jBox);
PhysicsSystem.getInstance().AddBody(_jBox);
}   
}


private function init2DObject():void {

var stats:StatsView = new StatsView(renderer);
addChild(stats);   
stage.addEventListener(MouseEvent.CLICK, onStageClick);

}

private function onStageClick(e:MouseEvent = null):void {
createLotOfBox();
} private function onEnterFrame(e:Event ):void {
physicsStep(); 
camera.x = Math.sin(newTime / 1000) * 200;
singleRender();
}


private function physicsStep():void {
newTime = getTimer();
deltaTime = ((newTime - currentTime) / 1000) * physicsSpeed;
currentTime = newTime;
PhysicsSystem.getInstance().Integrate(deltaTime); // phyisc step 5 is the speed
}
}
}