Отскок в игре

This red block will bounce up when it lands:

bounce

Another feature we need to add is bounce property.

bounce The property indicates whether the component will bounce when it falls to the ground due to gravity.

bounce The value of the property must be a number. 0 means that the component will not bounce at all, and 1 will make the component bounce back to the starting position after descending.

instance

function component(width, height, color, x, y, type) {
  this.type = type;
  this.width = width;
  this.height = height;
  this.x = x;
  this.y = y;
  this.speedX = 0;
  this.speedY = 0;
  this.gravity = 0.1;
  this.gravitySpeed = 0;
  this.bounce = 0.6;
  this.update = function() {
    ctx = myGameArea.context;
    ctx.fillStyle = color;
    ctx.fillRect(this.x, this.y, this.width, this.height);
  }
  this.newPos = function() {
    this.gravitySpeed += this.gravity;
    this.x += this.speedX;
    this.y += this.speedY + this.gravitySpeed;
    this.hitBottom();
  }
  this.hitBottom = function() {
    var rockbottom = this.gamearea.canvas.height - this.height;
    if (this.y > rockbottom) {
      this.y = rockbottom;
      this.gravitySpeed = -(this.gravitySpeed * this.bounce);
    }
  }
}

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