// Function to bounce balls against rectangle function bounce_rect(ball, rect) { let half_scale = scale * 0.5 let ul_corner = [rect.x, rect.y] let lr_corner = [rect.x + rect.wid, rect.y + rect.height] // if ball inside of rectangle if ( (ball.x - ball.r) > ul_corner[0] && (ball.y - ball.r) > ul_corner[1] && (ball.x + ball.r) < lr_corner[0] && (ball.y + ball.r) < lr_corner[1]) { // if a hit from right side --> move right if (ball.x - ball.r < rect.x + half_scale){ ball.dx = Math.abs(ball.dx) } // if a hit from left side --> move left if (ball.x + ball.r > lr_corner[0] - half_scale){ ball.dx = - Math.abs(ball.dx) } // if a hit from bottom side --> move down if (ball.y - ball.r < rect.y + half_scale){ ball.dy = speed } // if a hit from top side --> move up if (ball.y + ball.r > lr_corner[1] - half_scale){ ball.dy = -speed } } // When outside and hitting from top or bottom else if ((ball.x - ball.r > rect.x - half_scale && ball.x + ball.r < lr_corner[0] + half_scale)){ // move up if (ball.y + ball.r > rect.y - half_scale && ball.y < rect.y - half_scale){ ball.dy = -speed } // move down if (ball.y - ball.r < lr_corner[1] + half_scale && ball.y > lr_corner[1] + half_scale){ ball.dy = speed } } // when it's outside of the rectangle and on the same horizontal level else if (ball.y + ball.r < lr_corner[1] && ball.y - ball.r > rect.y) { // if a hit from right side --> move right if (ball.x - ball.r < lr_corner[0] + half_scale && ball.x > lr_corner[1]){ ball.dx = Math.abs(ball.dx) } // if a hit from left side --> move left if (ball.x + ball.r > rect.x - half_scale && ball.x < rect.x) { ball.dx = - Math.abs(ball.dx) } } return ball }