if (sheep.vx < 0 && sheepRect.left < obstacleRect.right && sheepRect.right > obstacleRect.right) {
              sheep.x += obstacleRect.right - sheepRect.left;
            }
            if (sheep.vy > 0 && sheepRect.bottom > obstacleRect.top && sheepRect.top < obstacleRect.top) {
              sheep.y -= sheepRect.bottom - obstacleRect.top;
            }
            if (sheep.vy < 0 && sheepRect.top < obstacleRect.bottom && sheepRect.bottom > obstacleRect.bottom) {
              sheep.y += obstacleRect.bot