我刚开始学习andEngine。我从andEngine的例子中得到了这个代码，我想要一辆汽车沿着线性方向移动。然后我计划通过sensores来控制它。但首先我希望汽车在游戏开始时自动移动。对你们所有人来说这可能是一个非常简单的问题，但我需要你的帮助
public class AndEngineTutorialActivity extends SimpleBaseGameActivity {
// ===========================================================
// Constants
// ===========================================================
private static final int RACETRACK_WIDTH = 64;
private static final int OBSTACLE_SIZE = 16;
private static final int CAR_SIZE = 16;
static final int CAMERA_WIDTH = RACETRACK_WIDTH * 5 ;
static final int CAMERA_HEIGHT = RACETRACK_WIDTH * 3;
// ===========================================================
// Fields
// ===========================================================
private Camera mCamera;
AccelerometerHelper mAccelerometerHelper;
private BitmapTextureAtlas mVehiclesTexture;
private TiledTextureRegion mVehiclesTextureRegion;
private BitmapTextureAtlas mBoxTexture;
private ITextureRegion mBoxTextureRegion;
private BitmapTextureAtlas mRacetrackTexture;
private ITextureRegion mRacetrackStraightTextureRegion;
private ITextureRegion mRacetrackCurveTextureRegion;
/*
private BitmapTextureAtlas mOnScreenControlTexture;
private ITextureRegion mOnScreenControlBaseTextureRegion;
private ITextureRegion mOnScreenControlKnobTextureRegion;
*/
private Scene mScene;
private PhysicsWorld mPhysicsWorld;
private Body mCarBody;
private TiledSprite mCar;
// ===========================================================
// Constructors
// ===========================================================
// ===========================================================
// Getter & Setter
// ===========================================================
// ===========================================================
// Methods for/from SuperClass/Interfaces
// ===========================================================
@Override
public EngineOptions onCreateEngineOptions() {
this.mCamera = new Camera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT);
mAccelerometerHelper = new AccelerometerHelper(this);
//AccelerometerHelper();
return new EngineOptions(true, ScreenOrientation.LANDSCAPE_FIXED, new RatioResolutionPolicy(CAMERA_WIDTH, CAMERA_HEIGHT), this.mCamera);
}
@Override
public void onCreateResources() {
BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/");
this.mVehiclesTexture = new BitmapTextureAtlas(this.getTextureManager(), 128, 16, TextureOptions.BILINEAR);
this.mVehiclesTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(this.mVehiclesTexture, this, "vehicles.png", 0, 0, 6, 1);
this.mVehiclesTexture.load();
this.mRacetrackTexture = new BitmapTextureAtlas(this.getTextureManager(), 128, 256, TextureOptions.REPEATING_NEAREST);
this.mRacetrackStraightTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mRacetrackTexture, this, "racetrack_straight.png", 0, 0);
this.mRacetrackCurveTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mRacetrackTexture, this, "racetrack_curve.png", 0, 128);
this.mRacetrackTexture.load();
/*
this.mOnScreenControlTexture = new BitmapTextureAtlas(this.getTextureManager(), 256, 128, TextureOptions.BILINEAR);
this.mOnScreenControlBaseTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mOnScreenControlTexture, this, "onscreen_control_base.png", 0, 0);
this.mOnScreenControlKnobTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mOnScreenControlTexture, this, "onscreen_control_knob.png", 128, 0);
this.mOnScreenControlTexture.load();
*/
this.mBoxTexture = new BitmapTextureAtlas(this.getTextureManager(), 32, 32, TextureOptions.BILINEAR);
this.mBoxTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mBoxTexture, this, "box.png", 0, 0);
this.mBoxTexture.load();
}
@Override
public Scene onCreateScene() {
this.mEngine.registerUpdateHandler(new FPSLogger());
this.mScene = new Scene();
this.mScene.setBackground(new Background(0, 0, 0));
this.mPhysicsWorld = new FixedStepPhysicsWorld(30, new Vector2(0, 0), false, 8, 1);
this.initRacetrack();
this.initRacetrackBorders();
this.initCar();
this.initObstacles();
// this.initOnScreenControls();
this.mScene.registerUpdateHandler(this.mPhysicsWorld);
return this.mScene;
}
@Override
public void onGameCreated() {
}
// ===========================================================
// Methods
// ===========================================================
/*private void initOnScreenControls() {
final AnalogOnScreenControl analogOnScreenControl = new AnalogOnScreenControl(0, CAMERA_HEIGHT - this.mOnScreenControlBaseTextureRegion.getHeight(), this.mCamera, this.mOnScreenControlBaseTextureRegion, this.mOnScreenControlKnobTextureRegion, 0.1f, this.getVertexBufferObjectManager(), new IAnalogOnScreenControlListener() {
@Override
public void onControlChange(final BaseOnScreenControl pBaseOnScreenControl, final float pValueX, final float pValueY) {
final Body carBody = AndEngineTutorialActivity.this.mCarBody;
final Vector2 velocity = Vector2Pool.obtain(pValueX * 5, pValueY * 5);
carBody.setLinearVelocity(velocity);
Vector2Pool.recycle(velocity);
final float rotationInRad = (float)Math.atan2(-pValueX, pValueY);
carBody.setTransform(carBody.getWorldCenter(), rotationInRad);
AndEngineTutorialActivity.this.mCar.setRotation(MathUtils.radToDeg(rotationInRad));
}
@Override
public void onControlClick(final AnalogOnScreenControl pAnalogOnScreenControl) {
/* Nothing. */
//}
/* });
analogOnScreenControl.getControlBase().setBlendFunction(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE_MINUS_SRC_ALPHA);
analogOnScreenControl.getControlBase().setAlpha(0.5f);
// analogOnScreenControl.getControlBase().setScaleCenter(0, 128);
// analogOnScreenControl.getControlBase().setScale(0.75f);
// analogOnScreenControl.getControlKnob().setScale(0.75f);
analogOnScreenControl.refreshControlKnobPosition();
this.mScene.setChildScene(analogOnScreenControl);
}*/
private void initCar() {
this.mCar = new TiledSprite(20, 20, CAR_SIZE, CAR_SIZE, this.mVehiclesTextureRegion, this.getVertexBufferObjectManager());
this.mCar.setCurrentTileIndex(0);
final FixtureDef carFixtureDef = PhysicsFactory.createFixtureDef(1, 0.5f, 0.5f);
this.mCarBody = PhysicsFactory.createBoxBody(this.mPhysicsWorld, this.mCar, BodyType.DynamicBody, carFixtureDef);
this.mPhysicsWorld.registerPhysicsConnector(new PhysicsConnector(this.mCar, this.mCarBody, true, false));
this.mScene.attachChild(this.mCar);
}
private void initObstacles() {
this.addObstacle(CAMERA_WIDTH / 2, RACETRACK_WIDTH / 2);
this.addObstacle(CAMERA_WIDTH / 2, RACETRACK_WIDTH / 2);
this.addObstacle(CAMERA_WIDTH / 2, CAMERA_HEIGHT - RACETRACK_WIDTH / 2);
this.addObstacle(CAMERA_WIDTH / 2, CAMERA_HEIGHT - RACETRACK_WIDTH / 2);
}
private void addObstacle(final float pX, final float pY) {
final Sprite box = new Sprite(pX, pY, OBSTACLE_SIZE, OBSTACLE_SIZE, this.mBoxTextureRegion, this.getVertexBufferObjectManager());
final FixtureDef boxFixtureDef = PhysicsFactory.createFixtureDef(0.1f, 0.5f, 0.5f);
final Body boxBody = PhysicsFactory.createBoxBody(this.mPhysicsWorld, box, BodyType.DynamicBody, boxFixtureDef);
boxBody.setLinearDamping(10);
boxBody.setAngularDamping(10);
this.mPhysicsWorld.registerPhysicsConnector(new PhysicsConnector(box, boxBody, true, true));
this.mScene.attachChild(box);
}
private void initRacetrack() {
/* Straights. */
{
final ITextureRegion racetrackHorizontalStraightTextureRegion = this.mRacetrackStraightTextureRegion.deepCopy();
racetrackHorizontalStraightTextureRegion.setTextureWidth(3 * this.mRacetrackStraightTextureRegion.getWidth());
final ITextureRegion racetrackVerticalStraightTextureRegion = this.mRacetrackStraightTextureRegion;
/* Top Straight */
this.mScene.attachChild(new Sprite(RACETRACK_WIDTH, 0, 3 * RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackHorizontalStraightTextureRegion, this.getVertexBufferObjectManager()));
/* Bottom Straight */
this.mScene.attachChild(new Sprite(RACETRACK_WIDTH, CAMERA_HEIGHT - RACETRACK_WIDTH, 3 * RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackHorizontalStraightTextureRegion, this.getVertexBufferObjectManager()));
/* Left Straight */
final Sprite leftVerticalStraight = new Sprite(0, RACETRACK_WIDTH, RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackVerticalStraightTextureRegion, this.getVertexBufferObjectManager());
leftVerticalStraight.setRotation(90);
this.mScene.attachChild(leftVerticalStraight);
/* Right Straight */
final Sprite rightVerticalStraight = new Sprite(CAMERA_WIDTH - RACETRACK_WIDTH, RACETRACK_WIDTH, RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackVerticalStraightTextureRegion, this.getVertexBufferObjectManager());
rightVerticalStraight.setRotation(90);
this.mScene.attachChild(rightVerticalStraight);
}
/* Edges */
{
final ITextureRegion racetrackCurveTextureRegion = this.mRacetrackCurveTextureRegion;
/* Upper Left */
final Sprite upperLeftCurve = new Sprite(0, 0, RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackCurveTextureRegion, this.getVertexBufferObjectManager());
upperLeftCurve.setRotation(90);
this.mScene.attachChild(upperLeftCurve);
/* Upper Right */
final Sprite upperRightCurve = new Sprite(CAMERA_WIDTH - RACETRACK_WIDTH, 0, RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackCurveTextureRegion, this.getVertexBufferObjectManager());
upperRightCurve.setRotation(180);
this.mScene.attachChild(upperRightCurve);
/* Lower Right */
final Sprite lowerRightCurve = new Sprite(CAMERA_WIDTH - RACETRACK_WIDTH, CAMERA_HEIGHT - RACETRACK_WIDTH, RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackCurveTextureRegion, this.getVertexBufferObjectManager());
lowerRightCurve.setRotation(270);
this.mScene.attachChild(lowerRightCurve);
/* Lower Left */
final Sprite lowerLeftCurve = new Sprite(0, CAMERA_HEIGHT - RACETRACK_WIDTH, RACETRACK_WIDTH, RACETRACK_WIDTH, racetrackCurveTextureRegion, this.getVertexBufferObjectManager());
this.mScene.attachChild(lowerLeftCurve);
}
}
private void initRacetrackBorders() {
final VertexBufferObjectManager vertexBufferObjectManager = this.getVertexBufferObjectManager();
final Rectangle bottomOuter = new Rectangle(0, CAMERA_HEIGHT - 2, CAMERA_WIDTH, 2, vertexBufferObjectManager);
final Rectangle topOuter = new Rectangle(0, 0, CAMERA_WIDTH, 2, vertexBufferObjectManager);
final Rectangle leftOuter = new Rectangle(0, 0, 2, CAMERA_HEIGHT, vertexBufferObjectManager);
final Rectangle rightOuter = new Rectangle(CAMERA_WIDTH - 2, 0, 2, CAMERA_HEIGHT, vertexBufferObjectManager);
final Rectangle bottomInner = new Rectangle(RACETRACK_WIDTH, CAMERA_HEIGHT - 2 - RACETRACK_WIDTH, CAMERA_WIDTH - 2 * RACETRACK_WIDTH, 2, vertexBufferObjectManager);
final Rectangle topInner = new Rectangle(RACETRACK_WIDTH, RACETRACK_WIDTH, CAMERA_WIDTH - 2 * RACETRACK_WIDTH, 2, vertexBufferObjectManager);
final Rectangle leftInner = new Rectangle(RACETRACK_WIDTH, RACETRACK_WIDTH, 2, CAMERA_HEIGHT - 2 * RACETRACK_WIDTH, vertexBufferObjectManager);
final Rectangle rightInner = new Rectangle(CAMERA_WIDTH - 2 - RACETRACK_WIDTH, RACETRACK_WIDTH, 2, CAMERA_HEIGHT - 2 * RACETRACK_WIDTH, vertexBufferObjectManager);
final FixtureDef wallFixtureDef = PhysicsFactory.createFixtureDef(0, 0.5f, 0.5f);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, bottomOuter, BodyType.StaticBody, wallFixtureDef);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, topOuter, BodyType.StaticBody, wallFixtureDef);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, leftOuter, BodyType.StaticBody, wallFixtureDef);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, rightOuter, BodyType.StaticBody, wallFixtureDef);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, bottomInner, BodyType.StaticBody, wallFixtureDef);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, topInner, BodyType.StaticBody, wallFixtureDef);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, leftInner, BodyType.StaticBody, wallFixtureDef);
PhysicsFactory.createBoxBody(this.mPhysicsWorld, rightInner, BodyType.StaticBody, wallFixtureDef);
this.mScene.attachChild(bottomOuter);
this.mScene.attachChild(topOuter);
this.mScene.attachChild(leftOuter);
this.mScene.attachChild(rightOuter);
this.mScene.attachChild(bottomInner);
this.mScene.attachChild(topInner);
this.mScene.attachChild(leftInner);
this.mScene.attachChild(rightInner);
}
// ===========================================================
// Inner and Anonymous Classes
// ===========================================================
}
答案 0 :(得分：1)
carBody.setLinearVelocity(velocity);
您已编辑的位。你已经宣称车身在物理世界是动态的，但它需要一个速度或一个力来施加它来移动它。
你可以使用
施加一个力或impulecarBody.mBody.applyForce(forceX, forceY, pointX, pointY);
carBody.mBody.applyLinearImpulse(impulseX, impulseY, pointX, pointY)
因此，确定您想要应用的矢量的方向和幅度，并在车体启动并注册到物理世界后执行此操作。
另外，你提到恒速 - 为了确保汽车没有任何线性阻尼，即
carBody.setLinearDamping(0.0f);
否则它会在行进距离上减慢。