[AndEngine学习教程] 第4节 制作人物动画

转自：/article/8024907.html

1.回顾

在上一节我们制作一个可以变幻的图形,这节将基于上一节的内容,制作一个行走的人物动画.在这里就称它为战士吧!呵呵!!!!

2.新使用到的资源

1.RepeatingSpriteBackground 游戏场景中使用到的背景绘制策略,本节中使用到草坪背景,由于背景大小是可以自动调节的,

不可能绘制一张固定大小的图片来作为背景.一方面占用空间大不说,另一方面背景图片经过缩放后效果也不好



2.PathModifier 为战士设定行走路径.需要说明的是:这里的路径是两点间的直线路径.比如只需要设定起点和终点.战士就会

沿着这两点间的直线进行移动

3.源代码陈述

1.关于RepeatingSpriteBackground ,这是一种重复绘制背景图片的策略,此类继承于SpriteBackground ,有两个构造函数:

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/**
* @param pCameraWidth
* @param pCameraHeight

* @param pTextureManager
* @param pBitmapTextureAtlasSource needs to be a power of two as otherwise the <code>repeating</code> feature doesn't work.
*/
public RepeatingSpriteBackground(finalfloat pCameraWidth,
finalfloat pCameraHeight,
final TextureManager pTextureManager,final IBitmapTextureAt lasSource pBitmapTextureAtlasSource,final VertexBufferObjectManager pVertexBufferObjectManager)throws
IllegalArgumentException {
this(pCameraWidth, pCameraHeight, pTextureManager, pBitmapTextureAtlasSource,1, pVertexBufferObjectManager);

}

public RepeatingSpriteBackground(finalfloat pCameraWidth,
finalfloat pCameraHeight,
final TextureManager pTextureManager,final IBitmapTextureAt lasSource pBitmapTextureAtlasSource,final
float pScale,final VertexBufferObjectManager pVertexBufferObjectManager)throws IllegalArgumentException {

super(null);

this.mScale = pScale;

this.mEntity =
this.loadSprite(pCameraWidth, pCameraHeight, pTextureManager, pBitmapTextureAtlasSource, pVertexBufferObjectManager);
}

/**
* @param pCameraWidth
* @param pCameraHeight
* @param pTextureManager
* @param pBitmapTextureAtlasSource needs to be a power of two as otherwise the <code>repeating</code> feature doesn't work.
*/
public RepeatingSpriteBackground(final float pCameraWidth, final float pCameraHeight, final TextureManager pTextureManager, final IBitmapTextureAt              lasSource pBitmapTextureAtlasSource, final VertexBufferObjectManager pVertexBufferObjectManager) throws IllegalArgumentException {
this(pCameraWidth, pCameraHeight, pTextureManager, pBitmapTextureAtlasSource, 1, pVertexBufferObjectManager);
}

public RepeatingSpriteBackground(final float pCameraWidth, final float pCameraHeight, final TextureManager pTextureManager, final IBitmapTextureAt                 lasSource pBitmapTextureAtlasSource, final float pScale, final VertexBufferObjectManager pVertexBufferObjectManager) throws IllegalArgumentException {
super(null);

this.mScale = pScale;
this.mEntity = this.loadSprite(pCameraWidth, pCameraHeight, pTextureManager, pBitmapTextureAtlasSource, pVertexBufferObjectManager);
}

本例子中使用到的是第一种构造函数,实现形式如下:

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private
static finalint CAMERA_WIDTH=800;
private staticfinal
int CAMERA_HEIGHT=480;
private Camera mCamera;
private RepeatingSpriteBackground mGrassBackground;
private TiledTextureRegion mPlayerTextureRegion;
private BitmapTextureAtlas mTexture;

@Override
public EngineOptions onCreateEngineOptions() {
// TODO Auto-generated method stub

mCamera = new Camera(0,0, CAMERA_WIDTH, CAMERA_HEIGHT);

EngineOptions engineOptions = new EngineOptions(true,ScreenOrientation.LANDSCAPE_SENSOR,new RatioResolutionPolicy(CAMERA_WIDTH,CAMERA_HEIGHT),
mCamera);
return engineOptions;
}

@Override
public void onCreateResources(
OnCreateResourcesCallback pOnCreateResourcesCallback)
throws Exception {
// TODO Auto-generated method stub

this.mTexture =
new BitmapTextureAtlas(getTextureManager(),
128, 128, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
this.mPlayerTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(mTexture,this,"player.png",0,0,3,4);

this.mGrassBackground =new RepeatingSpriteBackground(CAMERA_WIDTH, CAMERA_HEIGHT, getTextureManager(), AssetBitmapTextureAtlasSource.create(getAssets(),"background_grass.png"),
getVertexBufferObjectManager());

mTexture.load();
pOnCreateResourcesCallback.onCreateResourcesFinished();
}

private static final int CAMERA_WIDTH=800;
private static final int CAMERA_HEIGHT=480;
private Camera mCamera;
private RepeatingSpriteBackground mGrassBackground;
private TiledTextureRegion mPlayerTextureRegion;
private BitmapTextureAtlas mTexture;

@Override
public EngineOptions onCreateEngineOptions() {
// TODO Auto-generated method stub
mCamera = new Camera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT);
EngineOptions engineOptions = new EngineOptions(true,ScreenOrientation.LANDSCAPE_SENSOR, new RatioResolutionPolicy(CAMERA_WIDTH,CAMERA_HEIGHT), mCamera);
return engineOptions;
}

@Override
public void onCreateResources(
OnCreateResourcesCallback pOnCreateResourcesCallback)
throws Exception {
// TODO Auto-generated method stub
this.mTexture = new BitmapTextureAtlas(getTextureManager(), 128, 128, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
this.mPlayerTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(mTexture, this,"player.png", 0,0,3, 4);
this.mGrassBackground = new RepeatingSpriteBackground(CAMERA_WIDTH, CAMERA_HEIGHT, getTextureManager(), AssetBitmapTextureAtlasSource.create(getAssets(), "background_grass.png"), getVertexBufferObjectManager());

mTexture.load();
pOnCreateResourcesCallback.onCreateResourcesFinished();
}

然后在onCreateScene(OnCreateSceneCallback pOnCreateSceneCallback)函数中实现

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Scene mScene = new Scene();
mScene.setBackground(mGrassBackground);
pOnCreateSceneCallback.onCreateSceneFinished(mScene);

Scene mScene = new Scene();
mScene.setBackground(mGrassBackground);
pOnCreateSceneCallback.onCreateSceneFinished(mScene);

这样就把重复是的背景放置完成.

3.重点介绍

本例中用到一个72x128大小,3列4行的精灵战士



因此动画的创建方式为:

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final AnimatedSprite player =new AnimatedSprite(10,10,
48,64, mPlayerTextureRegion, getVertexBufferObjectManager());
mScene.attachChild(player);

final AnimatedSprite  player = new AnimatedSprite(10, 10, 48, 64, mPlayerTextureRegion, getVertexBufferObjectManager());
mScene.attachChild(player);

这样就把战士般到了屏幕上,但是此时,战士还不会动,为了让它动起来可要花费点力气的.呵呵!.有什么办法呢?就是给战士注册监听实体,

由于本例子要求的是战士按照设定路径移动,自然想到AndEngine中的Path类,定义一个可以围绕整个屏幕的path路线:

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final Path path =
new Path(5).to(10,10).to(10, CAMERA_HEIGHT -74).to(CAMERA_WIDTH-58,
CAMERA_HEIGHT -74).to(CAMERA_WIDTH-58,10).to(10,10);

final Path path = new Path(5).to(10, 10).to(10, CAMERA_HEIGHT - 74).to(CAMERA_WIDTH-58, CAMERA_HEIGHT - 74).to(CAMERA_WIDTH-58, 10).to(10, 10);

每个to函数为Path添加一个路径,最终形成一个从屏幕左上角->左下角->右下角->右上角->左上角的封闭路径.

有了以上基础,当然是添加基于Path类修改器啦.

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PathModifier pathModifier = new PathModifier(30.0f, path,new IPathModifierListener(){

@Override

public void onPathStarted(PathModifier pPathModifier,
IEntity pEntity) {
// TODO Auto-generated method stub

}

@Override
public void onPathWaypointStarted(PathModifier pPathModifier,
IEntity pEntity, int pWaypointIndex) {
// TODO Auto-generated method stub
switch(pWaypointIndex) {

case 0:
player.animate(new long[]{200,200,
200},6,
8,true);

break;
case 1:
player.animate(newlong[]{200,200,
200},3,
5,true);

break;
case 2:
player.animate(new long[]{200,200,
200},0,
2,true);

break;
case 3:
player.animate(newlong[]{200,200,
200},9,
11,true);

break;
}
}

@Override
public void onPathWaypointFinished(PathModifier pPathModifier,
IEntity pEntity, int pWaypointIndex) {
// TODO Auto-generated method stub

}

@Override

public void onPathFinished(PathModifier pPathModifier,
IEntity pEntity) {
// TODO Auto-generated method stub

}

},EaseSineInOut.getInstance());

PathModifier pathModifier = new PathModifier(30.0f, path, new IPathModifierListener(){

@Override
public void onPathStarted(PathModifier pPathModifier,
IEntity pEntity) {
// TODO Auto-generated method stub

}

@Override
public void onPathWaypointStarted(PathModifier pPathModifier,
IEntity pEntity, int pWaypointIndex) {
// TODO Auto-generated method stub
switch(pWaypointIndex) {
case 0:
player.animate(new long[]{200, 200, 200}, 6, 8, true);
break;
case 1:
player.animate(new long[]{200, 200, 200}, 3, 5, true);
break;
case 2:
player.animate(new long[]{200, 200, 200}, 0, 2, true);
break;
case 3:
player.animate(new long[]{200, 200, 200}, 9, 11, true);
break;
}
}

@Override
public void onPathWaypointFinished(PathModifier pPathModifier,
IEntity pEntity, int pWaypointIndex) {
// TODO Auto-generated method stub

}

@Override
public void onPathFinished(PathModifier pPathModifier,
IEntity pEntity) {
// TODO Auto-generated method stub

}

},EaseSineInOut.getInstance());

战士行走动作的变化是一个基础动画,所以需要Animate方法.但是战士在每个位置脸朝向不一样的,所以到了每个拐点的开始处都

需要修改动画的脸部朝向,这样就更加逼真点.从图片可以看出他们的对应关系.需要说明的是player.animate()函数:

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public void animate(finallong[] pFrameDurations,
finalint pFirstTileIndex,
finalint pLastTileIndex,
finalboolean pLoop) {

this.animate(pFrameDurations, pFirstTileIndex, pLastTileIndex, pLoop,null);

}

public void animate(final long[] pFrameDurations, final int pFirstTileIndex, final int pLastTileIndex, final boolean pLoop) {
this.animate(pFrameDurations, pFirstTileIndex, pLastTileIndex, pLoop, null);
}

各个参数的含义为:(战士图片中可以看出:有4组动作,每组动作为3个画面)

pFrameDurations:连续播放3个画面,三个long数据为每个动画的播放时间间隔,单位为毫秒;

pFirstTileIndex:动画的其起始列,按照"Z"字形排列计数.

pLastTileIndex:动画的结束序列,按照"Z"字形排列计数.

pLoop:是否循环播放

为了让战士行走路径也能循环,在PathModifier的基础上增加LoopEntityModifier

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LoopEntityModifier loopModifier = new LoopEntityModifier(pathModifier, -1);

LoopEntityModifier loopModifier = new LoopEntityModifier(pathModifier, -1);

有了loopModifier,当然是把它绑定到player上啦

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player.registerEntityModifier(loopModifier);

player.registerEntityModifier(loopModifier);

至此,整个设计任务完成了,下面看看运行的结果图片:







本例子源代码:http://download.csdn.net/detail/cen616899547/4705911