当球击中桨的边缘时，如何增加球的速度然后 return 回到原来的速度？

Question

如何提高球击中球拍边缘时的速度，然后return回到原来的速度？在这个乒乓球游戏中，我希望我的球在击中球拍边缘时加快速度，然后 return 在击中球拍中间时恢复到正常速度。我评论了一些 "if statements" 因为我试过它们但它们没有用。我使用的语言是 "processing"

Answer 1

你的代码有点乱，但我设法找到了解决你问题的方法。我注意到球的速度总是 "MIN_SPEED" 因为这就是你在弹跳方法中每次循环迭代对球位置的影响在查看代码后，我注意到在方法 "paddleBounce()" 中检测到与桨的碰撞，所以我去了那里并影响 MIN_SPEED 更高的值“8”作为示例，并完成我在绘图事件中添加了一个 lerp 版本，使 MIN_SPEED 的值以非线性方式缓慢回到“5”（因此它看起来平滑且良好）

这是最终代码：

 //size of the ball
int ballSize;

//position of the ball
float ballPositionX; 
float ballPositionY; 

//speed of the ball
float ballSpeedX, ballSpeedY;

//size of the paddles
final int PADDLE_WIDTH = (20);
final int PADDLE_HEIGHT = (100);

//coordinates of the LEFT paddle
float keyPaddleY;
float keyPaddleX;

//coordinates of the RIGHT paddle
float mousePaddleX ;
float mousePaddleY;

//score of keyboard
int keyScore = 0;

//score of mouse
int mouseScore = 0;

//movement of the ball
boolean moveDown = true;
boolean moveRight = true;

//gameover
boolean gameOver, moveNewSpeed;

//paddle speed
int paddleSpeed;

 float MIN_SPEED = 3;
final int MAX_SPEED = 6;



void setup () {

  size (500, 500);
  background (#FF7C00);
  frameRate (60);
  ballPositionX = width/2;
  ballPositionY = height/2;

  ballSpeedX = 3;
  ballSpeedY = 3;

  keyPaddleY= 200;
  keyPaddleX = 20;

  mousePaddleX= width - 40;
  mousePaddleY = 200;

  ballSize = 20;

  keyScore = 0;
  mouseScore = 0;

  paddleSpeed = 4;
}

void draw () {

  MIN_SPEED = lerp(MIN_SPEED,3,0.07);


  background (#FF7C00);
  drawGame ();
  bounce ();
  scoreCount ();
  paddleBounce ();
  gameover ();
  canvasBounce ();

  if (keyPressed) {

    if (keyCode == UP) {

      keyPaddleY = keyPaddleY - paddleSpeed;
    }

    /*if ((keyPaddleY == 0) || (keyPaddleY == height )) {

      paddleSpeed = 0;

    }*/ 

    if (keyCode == DOWN) {

      keyPaddleY = keyPaddleY + paddleSpeed;
    }
  }

  /*if ((mousePaddleY == 0) || (mousePaddleY == height )) {

      paddleSpeed = 0;

    }*/

  if (mousePressed) {

    if (mouseButton == LEFT ) {

      mousePaddleY = mousePaddleY - paddleSpeed;
    } 

    if (mouseButton == RIGHT ) {

      mousePaddleY = mousePaddleY + paddleSpeed;
    }
  }
}//VOID BRAC
void drawGame () {

  drawScore ();
  defaultBall ();


  //the ball
  fill ( 255);
  strokeWeight (2);
  ellipse (ballPositionX, ballPositionY, ballSize, ballSize);

  fill (255);
  strokeWeight (0.8);
  //the left paddle, which is controlled by the keyboard
  rect (keyPaddleX, keyPaddleY, PADDLE_WIDTH, PADDLE_HEIGHT);

  //the right paddle, which is controlled by the mouse
  rect (mousePaddleX, mousePaddleY, PADDLE_WIDTH, PADDLE_HEIGHT);
}

void drawScore() {

  textSize(20);

  String toPrint = "Keyboard: " + keyScore;

  text(toPrint, width/4-textWidth(toPrint)/2, 50);

  toPrint = "Mouse: "+ mouseScore;

  text(toPrint, width*3/4-textWidth(toPrint)/2, 50);
}

/*this funtion puts the ball back into the centre of the screen when it fails to hit either
 the paddle or the top or the bottom of the screen 
 */
void defaultBall () {

  if ((ballPositionX < -ballSize/2) || (ballPositionX > width + ballSize)) {

    ballPositionX = width/2;
    ballPositionY = height/2;
  }
}

void scoreCount () {

  if (ballPositionX  < -ballSize/2) {

    mouseScore = mouseScore + 1;
  }

  if (ballPositionX > width + ballSize) {

    keyScore =  keyScore + 1;
  }
}


void bounce () {
  //bouncing off the top and bottom of the screen  
  if (moveDown) {

    ballPositionY += MIN_SPEED +(sin(QUARTER_PI));
  } else {

    ballPositionY -= MIN_SPEED + (sin(QUARTER_PI));
  }

  if (moveRight) {

    ballPositionX += MIN_SPEED + (sin(HALF_PI + QUARTER_PI));

  } else {

    ballPositionX -= MIN_SPEED + (sin(-PI));
  }

  /*if (moveNewSpeed) {

   ballPositionX = ballPositionX + MAX_SPEED + (sin(QUARTER_PI));
   } else {

   ballPositionX = ballPositionX - MAX_SPEED + (cos(QUARTER_PI));
   }
  */
}

void paddleBounce () {


  if (ballPositionX <= (keyPaddleX + PADDLE_WIDTH + ballSize/2) && ballPositionY < (keyPaddleY + 100) && ballPositionY > (keyPaddleY) && ballPositionX > keyPaddleX  ) {

    moveRight = true;
    MIN_SPEED = 8;


  }


  if (ballPositionX >= (mousePaddleX - ballSize/2) && ballPositionY > (mousePaddleY) && ballPositionY < (mousePaddleY + 100) && ballPositionX < mousePaddleX ) {

    moveRight = false;
    MIN_SPEED = 8;


  }

  /*if (ballPositionX == keyPaddleX + PADDLE_WIDTH && ballPositionY == keyPaddleY + PADDLE_WIDTH ) {

   moveNewSpeed  = false;  

   } 

   if (ballPositionX == mousePaddleX && ballPositionY == mousePaddleY) {

   moveNewSpeed = true;

   }   

   */

}

void canvasBounce () {

  if (ballPositionY < ballSize/2) {

    moveDown = true;
  }

  if (ballPositionY > height - ballSize/2) {

    moveDown = false;
  }

}

void gameover () {

  if (gameOver) {

    ballSpeedX = 0;
    ballSpeedY = 0;
    paddleSpeed = 0;
    ballPositionX = width/2;
    ballPositionY = height/2;

    textSize(50);

    fill (random(255), random(255), random (255));

    String toPrint = "GAME OVER!!";

    text(toPrint, width/2-textWidth(toPrint)/2, height/2);
  }

  if (keyScore == 11 || mouseScore == 11) {

    gameOver = true;
  } else {

    gameOver = false;
  }
}

Answer 2

I want my ball to increase its speed when it hits the edge of a paddle and then return back to its normal speed when it hits the middle of the paddle

添加一个保存当前速度的变量：

final int MIN_SPEED = 3;
final int MAX_SPEED = 6;
float currentSpeed = (float)MIN_SPEED;

在函数 bounce:

中使用此变量代替 MIN_SPEED

void bounce () {
    //bouncing off the top and bottom of the screen  
    if (moveDown) {
        ballPositionY += currentSpeed +(sin(QUARTER_PI));
    } else {
        ballPositionY -= currentSpeed + (sin(QUARTER_PI));
    }

    if (moveRight) {
        ballPositionX += currentSpeed + (sin(HALF_PI + QUARTER_PI));

    } else {
        ballPositionX -= currentSpeed + (sin(-PI));
    }
}

要评估球是否击中面板的中间，您必须计算球拍到球拍中心的距离。如果球拍距离中心很远（一直未达到 MAX_SPEED），请提高速度，如果球拍靠近中心，则将速度重置为 MIN_SPEED：

void paddleBounce () {

    boolean hitMousePaddleX = ballPositionX >= (mousePaddleX - ballSize/2) && ballPositionX < mousePaddleX;
    boolean hitMousePaddleY = ballPositionY > (mousePaddleY) && ballPositionY < (mousePaddleY + PADDLE_HEIGHT);
    if (hitMousePaddleX && hitMousePaddleY) {

        float distToMidMouse = abs(ballPositionY - (mousePaddleY + PADDLE_HEIGHT/2));
        if ( distToMidMouse < 20.0 ) {
            currentSpeed = MIN_SPEED;
        } else if (currentSpeed < MAX_SPEED) {
            if (currentSpeed < MAX_SPEED) {
                currentSpeed += 0.5;
            }
        } 

        moveRight = false;
    }

    boolean hitKeyPaddleX = ballPositionX <= (keyPaddleX + PADDLE_WIDTH + ballSize/2) && ballPositionX > keyPaddleX;
    boolean hitKeyPaddleY = ballPositionY < (keyPaddleY + PADDLE_HEIGHT) && ballPositionY > keyPaddleY;
    if (hitKeyPaddleX && hitKeyPaddleY) {

        float distToMidKey = abs(ballPositionY - (keyPaddleY + PADDLE_HEIGHT/2));
        if ( distToMidKey < 20.0 ) {
            currentSpeed = MIN_SPEED;
        } else {
            if (currentSpeed < MAX_SPEED) {
                currentSpeed += 0.5;
            }
        }   

        moveRight = true;
    }
}

如果游戏中有新球，速度不会重置为MIN_SPEED：

void scoreCount () {

    if (ballPositionX  < -ballSize/2) {

    mouseScore += 1;
    currentSpeed = MIN_SPEED;
    }

    if (ballPositionX > width + ballSize) {

    keyScore +=  1;
    currentSpeed = MIN_SPEED;
    }
}

屁股增加你可以通过增加速度来给球着色：

void drawGame () {

    drawScore ();
    defaultBall ();

    //the ball
    float fSpeed = 1.0 - (currentSpeed - MIN_SPEED) / (MAX_SPEED - MIN_SPEED);
    fill(255, 255*fSpeed, 255*fSpeed);
    strokeWeight (2);
    ellipse (ballPositionX, ballPositionY, ballSize, ballSize);

    fill (255);
    strokeWeight (0.8);
    //the left paddle, which is controlled by the keyboard
    rect (keyPaddleX, keyPaddleY, PADDLE_WIDTH, PADDLE_HEIGHT);

    //the right paddle, which is controlled by the mouse
    rect (mousePaddleX, mousePaddleY, PADDLE_WIDTH, PADDLE_HEIGHT);
}

当球击中桨的边缘时，如何增加球的速度然后 return 回到原来的速度？

How to increase the speed of the ball when it hits the edge of a paddle and then return back to original speed?

processing