I'm currently following along a tutorial to get a better understanding of pygame. What I'm trying to do now is make this program that currently spawns 100 random circles (balls) actually bounce off each-other when they come in contact/collide.
As of now I have it detecting if the two circles collide and bounce (sorta) off each-other. I looked around and found many posts asking somewhat the same question but the thing I kept noticing is that a lot of them require certain attributes that each ball has (velocity, radius, etc..) which I don't really have. What I have now is when it detects a collision it simply swaps the x and y's of the balls to create a bounce affect, the issue is that it seems very buggy and a lot of the circles start spazzing out.
So I'm wondering if I need to add more attributes to each individual ball or am incorrectly swapping the x and y's? I'm not entirely sure if I'm on the right track or if I'm just overthinking this since all I'm trying to do is create a very simple bounce affect where they all just have a constant speed.
code that I'm using to create the bounce :
for i in range(0, len(ball_list)): for j in range(i + 1, len(ball_list)): if pygame.Vector2(ball_list[i].x, ball_list[i].y).distance_to( pygame.Vector2(ball_list[j].x, ball_list[j].y)) <= 25: ball_list[i].x, ball_list[j].x = ball_list[j].x, ball_list[i].x ball_list[i].y, ball_list[j].y = ball_list[j].y, ball_list[i].y
import pygame import random # Define some colors BLACK = (0, 0, 0) SCREEN_WIDTH = 1000 SCREEN_HEIGHT = 1000 BALL_SIZE = 25 class Ball: """ Class to keep track of a ball's location and vector. """ def __init__(self): self.x = 0 self.y = 0 self.change_x = 0 self.change_y = 0 self.color = None def make_ball(): """ Function to make a new, random ball. """ ball = Ball() # Starting position of the ball. # Take into account the ball size so we don't spawn on the edge. ball.x = random.randrange(BALL_SIZE, SCREEN_WIDTH - BALL_SIZE) ball.y = random.randrange(BALL_SIZE, SCREEN_HEIGHT - BALL_SIZE) # Speed and direction of rectangle ball.change_x = random.randrange(-2, 3) ball.change_y = random.randrange(-2, 3) ball.color = (random.randrange(256), random.randrange(256), random.randrange(256)) return ball def main(): """ This is our main program. """ pygame.init() # Set the height and width of the screen size = [SCREEN_WIDTH, SCREEN_HEIGHT] screen = pygame.display.set_mode(size) pygame.display.set_caption("Bouncing Balls") # Loop until the user clicks the close button. done = False # Used to manage how fast the screen updates clock = pygame.time.Clock() ball_list =  ball = make_ball() ball_list.append(ball) for i in range(100): ball = make_ball() ball_list.append(ball) # -------- Main Program Loop ----------- while not done: # --- Event Processing for event in pygame.event.get(): if event.type == pygame.QUIT: done = True elif event.type == pygame.KEYDOWN: # Space bar! Spawn a new ball. if event.key == pygame.K_SPACE: ball = make_ball() ball_list.append(ball) # --- Logic for ball in ball_list: # Move the ball's center ball.x += ball.change_x ball.y += ball.change_y # Bounce the ball if needed if ball.y > SCREEN_HEIGHT - BALL_SIZE or ball.y < BALL_SIZE: ball.change_y *= -1 if ball.x > SCREEN_WIDTH - BALL_SIZE or ball.x < BALL_SIZE: ball.change_x *= -1 for i in range(0, len(ball_list)): for j in range(i + 1, len(ball_list)): if pygame.Vector2(ball_list[i].x, ball_list[i].y).distance_to( pygame.Vector2(ball_list[j].x, ball_list[j].y)) <= 25: ball_list[i].x, ball_list[j].x = ball_list[j].x, ball_list[i].x ball_list[i].y, ball_list[j].y = ball_list[j].y, ball_list[i].y # --- Drawing # Set the screen background screen.fill(BLACK) # Draw the balls for ball in ball_list: pygame.draw.circle(screen, ball.color, [ball.x, ball.y], BALL_SIZE) # --- Wrap-up # Limit to 60 frames per second clock.tick(60) # Go ahead and update the screen with what we've drawn. pygame.display.flip() # Close everything down pygame.quit() if __name__ == "__main__": main()