当我尝试将TweenLite与Bitmap一起使用时，我遇到以下问题：
将TweenLite应用于位图（tempScore.bitmap）时出现奇怪的错误消息。 GetBounds有效。位图具有透明度。有谁知道为什么它不起作用？任何帮助赞赏。感谢：。）
使用getBounds-Method时，我得到了这个：
tempScore.bitmap.getBounds(this)(x=2.35, y=-0.45, w=25, h=18)
这是错误消息：
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at com.greensock.plugins::TransformAroundPointPlugin/onInitTween()
at com.greensock.plugins::TransformAroundCenterPlugin/onInitTween()
at com.greensock::TweenLite/init()
at com.greensock::TweenLite/renderTime()
at com.greensock.core::SimpleTimeline/renderTime()
at com.greensock::TweenLite$/updateAll()
我导入和激活的库看起来像这样：
import com.greensock.*;
import com.greensock.TweenLite;
import com.greensock.plugins.TweenPlugin;
import com.greensock.plugins.TransformAroundCenterPlugin;
import com.greensock.plugins.TransformAroundPointPlugin;
import com.greensock.easing.*;
import com.greensock.plugins.AutoAlphaPlugin;
import com.greensock.plugins.ColorTransformPlugin;
import com.greensock.plugins.ColorMatrixFilterPlugin;
TweenPlugin.activate([TransformAroundCenterPlugin, TransformAroundPointPlugin, ColorTransformPlugin,
ColorMatrixFilterPlugin]);
这是我尝试在tempScore上使用TweenLite的部分：
var scoreTextLength:int = scoreManager.scores.length - 1;
for (var counter:int = scoreTextLength; counter >= 0; counter--)
{
tempScore = scoreManager.scores[counter];
tempScore.startDelay = true;
TweenLite.to(tempScore.bitmap, 2, {transformAroundCenter: {scale:2}});
trace("tempScore.bitmap.getBounds(this)" + tempScore.bitmap.getBounds(this));
if (tempScore.update())
{
disposeScore(counter);
}
}
到目前为止，我可以看到getBounds值正常。我的游戏基于游戏框架。里面有一个渲染器。 如果我错了，可以称我为白痴，但框架和tweenlite的渲染器是否可能相互影响？
TweenLite与其他类似对象（如tempAsteroid）存在问题。使用copyPixels（blitting-method）将大量对象绘制到画布上。
tempScore是一个Score-object。 Score对象基于BasicBlitArrayObject。否则，此对象扩展EventDispatcher。我希望这些小信息有所帮助。
这是用于管理tempScore的外观和属性的scoreManager：
package com.cosmicward.src.classes
{
import flash.display.*;
import flash.text.*;
import flash.geom.*;
import com.framework_mod.src.BlitArrayAsset;
public class ScoreManager
{
public var scoreBitmapData:BitmapData;
public var scoreBitmap:Bitmap;
public var scoreAnimationFrames:Array = [];
public var scores:Array;
public var tempScore:Score;
private var textfield:TextField = new TextField();
private var textFormat:TextFormat = new TextFormat();
private var $textWidth:int;
private var $textHeight:int;
private var rec:Rectangle;
public var scoreCount:int;
public var scoreCountTwo:int;
public var scoreCountThree:int;
private var drawingCanvas:Shape = new Shape();
private var point0:Point = new Point(0, 0);
public function ScoreManager()
{
}
public function createScoreLook(textWidth:int, textHeight:int, text:String, textFormat:TextFormat):void {
var tempBlitArrayAsset:BlitArrayAsset = new BlitArrayAsset();
scoreBitmapData = new BitmapData(textWidth, textHeight, true, 0x00000000);
var font:ArialBold = new ArialBold();
textFormat.font = "ArialBold";
textFormat.font = font.fontName;
Font.registerFont(ArialBold);
textfield.embedFonts = true;
textfield.blendMode = BlendMode.LAYER;
//textfield.autoSize = TextFieldAutoSize.LEFT;
textfield.defaultTextFormat = textFormat;
textfield.setTextFormat(textFormat);
textfield.selectable = false;
textfield.text = text;
trace("drawingCanvas.height =" + drawingCanvas.height);
trace("drawingCanvas.width =" + drawingCanvas.width);
scoreBitmapData.draw(textfield);/
$textWidth = textWidth;
$textHeight = textHeight;
//*** end look
}
public function createScores(xPos:Number, yPos:Number, stopAnimation:int = 5,
scoreDelay:int = 10, scoreLife:int = 40):void {
var tempScore:Score = new Score(5, 1315, 5, 995);
tempScore.bitmapData = scoreBitmapData;
scoreBitmap = new Bitmap(tempScore.bitmapData);
tempScore.bitmap = scoreBitmap;
tempScore.x = xPos;
tempScore.y = yPos;
tempScore.life = scoreLife;
tempScore.lifeCount = 0;
tempScore.widthObject = $textWidth;
tempScore.heightObject = $textHeight;
tempScore._delay = scoreDelay;
tempScore.delayCount = 0;
tempScore.nextX = tempScore.x;
tempScore.nextY = tempScore.y;
scores.push(tempScore);
}
}
}
以下是BasicBlitArrayObject的一些代码（tempScore依赖于它（即Score-object）：
package com.framework_mod.src
{
import flash.display.BitmapData;
import flash.geom.Point;
import flash.events.EventDispatcher;
import flash.geom.Rectangle;
import flash.display.Bitmap;
public class BasicBlitArrayObject extends EventDispatcher{
public var x:Number = 0;
public var y:Number = 0;
public var nextX:Number = 0;
public var nextY:Number = 0;
public var dx:Number = 0;
public var dy:Number = 0;
public var frame:int = 0;
public var bitmapData:BitmapData;
public var bitmap:Bitmap;
public var animationList:Array = [];
public var testList:Array = [];
public var point:Point = new Point(0, 0);
public var speed:Number = 0;
public var xMax:int = 0;
public var yMax:int = 0;
public var xMin:int = 0;
public var yMin:int = 0;
public var aniType:int = 1;
public var health:int = 0;
public var _size:int = 0;
public var score:int = 0;
public var _damage:int = 0;
public var count:int = 0;
public var bitmapSize:int = 0;
public var life:int = 0;
public var lifeCount:int = 0;
public var startCount:Boolean;
public var _delay:int = 0;
public var delayCount:int = 0;
public var startDelay:Boolean;
public var _stop:int;
public var stopAni:Boolean;
public var stopAniCount:int = 0;
public var _type:int = 0;
public var shield:int = 0;
public var healthPoints:int = 0;
public var widthObject:int;
public var heightObject:int;
public var boost:Number;
public var boostLfe:int;
public var weaponLfe:int;
public var _projXAdjust:Number;
public var _projYAdjust:Number;
public var number:int;
public var _offset:int;
public var marked:Boolean;
public var objMove:Boolean;
public var removeObj:Boolean;
public var finished:Boolean;
public function BasicBlitArrayObject(xMin:int, xMax:int, yMin:int, yMax:int)
{
this.xMin = xMin;
this.xMax = xMax;
this.yMin = yMin;
this.yMax = yMax;
//trace("basicblittarrayobject");
}
public function updateFrame(inc:int, aniType:int = 1):void
{
frame += inc;
switch (aniType) {
case 1:
if (frame > animationList.length - 1){
frame = 0;
}
bitmapData = animationList[frame];
break;
case 2:
if (frame > animationList.length - 1){
frame = 0;
}
bitmapData = animationList[1][frame];
break;
}
}
public function render(canvasBitmapData:BitmapData):void {
x = nextX;
y = nextY;
point.x = x;
point.y = y;
canvasBitmapData.copyPixels(bitmapData, bitmapData.rect, point);
}
public function dispose():void {
bitmapData.dispose();
bitmapData = null;
bitmap = null;
animationList = null;
point = null;
}
}
}
答案 0 :(得分：1)
我认为这个问题很简单，但决议却不是。您尝试转换的对象是blitted。所以他们没有加入舞台。所以对象的stage属性为null。 我怀疑TransformAroundPoint插件正在尝试使用对象的stage属性，这就是抛出你正在看到的空对象错误。 要查看一个简单的示例，请创建一个非常简单的文件。 创建两个位图，向舞台添加一个，不添加另一个。 将补间应用于舞台实例，它将起作用。 然后将补间应用到场外实例，你应该得到你在游戏中得到的同样的错误。
您需要做的是自己处理变换。不要使用TweenLite围绕某个点旋转，而是自己动手。 幸运的是，Stack Overflow已经在该主题上有一个很棒的主题！ Rotate around a point that is not (0,0)