java - 在Android应用程序中定义位图的大小

Question

我的 Android 游戏的 Sprite 在各处弹跳，但在屏幕的右侧和底部边缘/墙壁上， Sprite 在弹跳之前会稍微消失。

我知道这与位图的大小有关，并且它位于下面的 Sprite 类中，但我不知道需要修改什么。

这是 Sprite 类:

public class Sprite extends AppCompatActivity {

private static final int BMP_ROWS = 4;
private static final int BMP_COLUMNS = 3;
//x,y position of sprite - initial position (0,50)
private int x = 0;
private int y = 0;
private int xSpeed = 5;//Horizontal increment of position (speed)
private int ySpeed = 5;// Vertical increment of position (speed)
private GameView gameView;
private Bitmap spritebmp;
private int currentFrame = 0;
//Width and Height of the Sprite image
private int bmp_width;
private int bmp_height;
// Needed for new random coordinates.
private Random random = new Random();

private SoundPool mySound;
int zapSoundId;

public Sprite(GameView gameView) {
    this.gameView = gameView;
    spritebmp = BitmapFactory.decodeResource(gameView.getResources(),
            R.drawable.bad4);
    this.bmp_width = spritebmp.getWidth() / BMP_COLUMNS;
    this.bmp_height = spritebmp.getHeight() / BMP_ROWS;
    xSpeed = random.nextInt(15) + 1;
    ySpeed = random.nextInt(15) + 1;
    x = random.nextInt(gameView.getWidth() - bmp_width);
    y = random.nextInt(gameView.getHeight() - bmp_height);


}

public Sprite(GameView gameView, Bitmap bmp) {

        spritebmp.recycle();
}

//update the position of the sprite
public void update() {
    x = x + xSpeed;
    y = y + ySpeed;
    bounce();

    //y = random.nextInt(gameView.getWidth());
    //wrapAround(); //Adjust motion of sprite.
}

private void bounce() {
    if (x <= 0 || x >= gameView.getWidth() ) {
        xSpeed = xSpeed * -1;
    }
    if (y <= 0 || y >= gameView.getHeight() ) {
        ySpeed = ySpeed * -1;
    }
    currentFrame = ++currentFrame % BMP_COLUMNS;

}

public void draw(Canvas canvas) {

    update();
    int srcX = currentFrame * bmp_width;
    int srcY;
    if (xSpeed > 0) {
        srcY = 0 * bmp_height;
    }
    else {
        srcY = 1 * bmp_height;
    }
    // Create Rect around the source image to be drawn
    Rect src = new Rect(srcX, srcY, srcX + bmp_width, srcY + bmp_height);
    // Rect for destination image
    Rect dst = new Rect(x, y, x + bmp_width, y + bmp_height);
    //
    // Draw the image frame
    canvas.drawBitmap(spritebmp, src, dst, null);

}


// Checks if the sprite was touched
public boolean wasItTouched(float ex, float ey) {
    boolean touched = false;
    if ((x <= ex) && (ex < x + bmp_width) &&
            (y <= ey) && (ey < y + bmp_height)) {
        touched = true;
    }


    return touched;

}

}

非常感谢任何帮助。

谢谢

Answer 1

我已经修复了它。

我需要将'this.bmp_width'和'this.bmp_height'添加到我的bounce()方法中。

private void bounce() {
    if (x <= 0 || x + this.bmp_width >= gameView.getWidth() ) {
        xSpeed = xSpeed * -1;
    }
    if (y <= 0 || y + this.bmp_height >= gameView.getHeight() ) {
        ySpeed = ySpeed * -1;
    }
    currentFrame = ++currentFrame % BMP_COLUMNS;

}