骨骼的绑定归根结底就是将目标骨骼的位置以及旋转数据，同步给要绑定的显示对象。
先来看BindingTag.as
package away3d.entities
{ import away3d.arcane;
import away3d.animators.SkeletonAnimator;
import away3d.animators.data.JointPose;
import away3d.containers.ObjectContainer3D;
use namespace arcane
public class BindingTag extends ObjectContainer3D
{
private var _skeletonAnimator:SkeletonAnimator;
private var _skeletonIndex:int;
/**
*
* @param skeletonAnimator
* @param skeletonIndex 要绑定的骨骼索引
*
*/ public function BindingTag(skeletonAnimator:SkeletonAnimator, skeletonIndex:int)
{
super();
_skeletonAnimator = skeletonAnimator;
_skeletonIndex = skeletonIndex;
}
public function notifyBindingTransformChange():void
{
invalidateTransform();
}
override protected function updateSceneTransform():void
{
if (_parent)
{
var jointPoses:Vector.<JointPose> = _skeletonAnimator.globalPose.jointPoses;
if(jointPoses && jointPoses.length)
{
//取到骨骼数据并同步给当前对象
_sceneTransform.copyFrom( jointPoses[_skeletonIndex].toMatrix3D() );
_sceneTransform.append( _parent.sceneTransform );
_sceneTransform.prepend(transform);
}
}
_sceneTransformDirty = false;
}
override public function dispose():void
{
//TODO:
}
}
}BindingTag即是绑定在指定骨骼上的容器，假如你想绑定武器或特效， 只要将他们addChild到该BindingTag就可以了。 下面看怎样将BindingTag集成到Away3D里面。 为AnimatorBase添加Exit_Frame事件，至于为什么要加这个Exit_Frame事件，后面再来解释。 分别在start()以及stop()方法里添加、移除Exit_Frame事件
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if(!_broadcaster.hasEventListener(Event.EXIT_FRAME))
_broadcaster.addEventListener(Event.ENTER_FRAME, onExitFrame);
if(_broadcaster.hasEventListener(Event.EXIT_FRAME))
_broadcaster.removeEventListener(Event.EXIT_FRAME, onExitFrame);
protected function onExitFrame(event:Event):void
{ //Override
} |
为SkeletonAnimator添加addBindingTagByName，addBindingTagByIndex方法 以及复写onExitFrame
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/** * 绑定至通过名字指定的骨骼上
* @param boneName
* @return
*
*/ public function addBindingTagByName(boneName:String):BindingTag
{
var boneIndex : int = globalPose.jointPoseIndexFromName(boneName);
if(boneIndex<0)//骨骼不存在
return null;
return addBindingTagByIndex(boneIndex);
}
/**
* 绑定至通过骨骼索引指定的骨骼上
* @param boneIndex
* @return
*
*/ public function addBindingTagByIndex(boneIndex:int):BindingTag
{
var bindingTag:BindingTag = new BindingTag(this, boneIndex);
for(var i:int = 0; i < _owners.length; i++)
{
_owners[i].addChild(bindingTag);//将bindingTag添加至骨骼对应的Mesh
}
if(!_bindingTags)_bindingTags = new Vector.<BindingTag>();
_bindingTags.push(bindingTag);
return bindingTag;
}
override protected function onExitFrame(event:Event):void
{
if(_bindingTags && _bindingTags.length)
{
for (var i:int = 0; i < _bindingTags.length; i++)
{
_bindingTags[i].notifyBindingTransformChange();
}
}
}
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到这里就已经代码已经都修改添加完成了，下面来说下为什么要在Exit_Frame事件中通知 BindingTag更新.骨骼的更新是在skeletonAnimatior的updateGlobalProperties方法中 进行的，他的更新是在引擎执行完traverse后执行的，所以为了保证每次执行traverse时都能让 BindingTag根据骨骼更新，需在Exit_Frame时通知，否则BindingTag的更新总会延迟一帧， 从而导致跟随出现错位问题。