(11)、andengine之CardinalSplineMoveModifier创建出一个W形

import org.andengine.engine.camera.Camera;
import org.andengine.engine.options.EngineOptions;
import org.andengine.engine.options.ScreenOrientation;
import org.andengine.engine.options.resolutionpolicy.RatioResolutionPolicy;
import org.andengine.entity.modifier.CardinalSplineMoveModifier;
import org.andengine.entity.modifier.CardinalSplineMoveModifier.CardinalSplineMoveModifierConfig;
import org.andengine.entity.modifier.DelayModifier;
import org.andengine.entity.modifier.LoopEntityModifier;
import org.andengine.entity.modifier.ParallelEntityModifier;
import org.andengine.entity.modifier.RotationModifier;
import org.andengine.entity.modifier.SequenceEntityModifier;
import org.andengine.entity.primitive.Rectangle;
import org.andengine.entity.scene.Scene;
import org.andengine.entity.scene.background.Background;
import org.andengine.entity.util.FPSLogger;
import org.andengine.ui.activity.SimpleBaseGameActivity;
import org.andengine.util.math.MathUtils;
import org.andengine.util.modifier.ease.EaseLinear;

import android.util.DisplayMetrics;
/**
 * CardinalSplineMoveModifier（基数样条移动修改器）。
 * demo的效果是依靠矩形的运动创造出一个W形
 */
public class CardinalSplineMoveModifierWActivity extends SimpleBaseGameActivity
{
 private static int winWidth = 854;
 private static int winHeight = 480;
 
 private static final float RECTANGLE_SIZE = 25.0f;
 
 //时间(秒)
 private static final float DURATION = 4.0f;
 
 private static float[][] controlPointXy;

 @Override
 public EngineOptions onCreateEngineOptions()
 {
  setScreenDisplay();
  Camera camera = new Camera(0, 0, winWidth, winHeight);
  return new EngineOptions
  (
   true,
   ScreenOrientation.LANDSCAPE_FIXED,
   new RatioResolutionPolicy(winWidth, winHeight),
   camera
  );
 }

 @Override
 protected void onCreateResources()
 {

 }

 @Override
 protected Scene onCreateScene()
 {
  this.mEngine.registerUpdateHandler(new FPSLogger());
  Scene scene = new Scene();
  scene.setBackground(new Background(0, 0, 0));
  
  //创建并添加矩形
  for (int j = 0; j < 400; j++)
  {
   createRectangle(scene);
  }
  
  return scene;
 }
 
 private void createRectangle(Scene scene)
 {
  Rectangle rectangle = new Rectangle(-RECTANGLE_SIZE, -RECTANGLE_SIZE, RECTANGLE_SIZE, RECTANGLE_SIZE, this.getVertexBufferObjectManager());
 // rectangle.setBlendFunction(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE);
  //设置矩形颜色(使用了引擎的随机数)
  rectangle.setColor(MathUtils.random(0.0f, 1.0f), MathUtils.random(0.0f, 1.0f), MathUtils.random(0.0f, 1.0f), 0.5f);
  //控制点的配置(记录了控制点和张力，CardinalSplineMoveModifier根据配置改变路径)
  CardinalSplineMoveModifierConfig cardinalSplineMoveModifierConfig = new CardinalSplineMoveModifierConfig(controlPointXy.length, MathUtils.random(-1.0f, 1.0f));
  //填充(设置)控制点
  for (int i = 0; i < controlPointXy.length; i++)
  {
   cardinalSplineMoveModifierConfig.setControlPoint(i, controlPointXy[i][0], controlPointXy[i][1]);
  }
  SequenceEntityModifier sequenceEntityModifier = new SequenceEntityModifier
  (
   new DelayModifier(MathUtils.random(0.0f, DURATION)),
   //无限循环，跑完一遍,然后重复跑
   new LoopEntityModifier
   (
    new ParallelEntityModifier
    (
     new CardinalSplineMoveModifier(DURATION, cardinalSplineMoveModifierConfig, EaseLinear.getInstance()),
     new RotationModifier(DURATION, 45, 315)
    )
   )
  );
  
  //注册实体修改器
  rectangle.registerEntityModifier(sequenceEntityModifier);
  
  scene.attachChild(rectangle);
 }

 /**
  * 设置屏幕大小
  */
 private void setScreenDisplay()
 {
  DisplayMetrics displayMetrics = new DisplayMetrics();
  getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
  winWidth = displayMetrics.widthPixels;
  winHeight = displayMetrics.heightPixels;
  
  //控制点的x,y
  controlPointXy = new float[][]
  {
   {1.0f*(winWidth/4)-RECTANGLE_SIZE/2 , 1.0f*(winHeight/4)-RECTANGLE_SIZE/2},
   {1.5f*(winWidth/4)-RECTANGLE_SIZE/2 , 3.0f*(winHeight/4)-RECTANGLE_SIZE/2},
   {2.0f*(winWidth/4)-RECTANGLE_SIZE/2 , 2.0f*(winHeight/4)-RECTANGLE_SIZE/2},
   {2.5f*(winWidth/4)-RECTANGLE_SIZE/2 , 3.0f*(winHeight/4)-RECTANGLE_SIZE/2},
   {3.0f*(winWidth/4)-RECTANGLE_SIZE/2 , 1.0f*(winHeight/4)-RECTANGLE_SIZE/2}
  };
  
 }

}