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
whole-code:
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()
Read more here: https://stackoverflow.com/questions/66270255/how-to-make-circles-bounce-of-each-other-with-the-same-speed
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