No, there was a sys.MAXINT constant in older versions of python, but now integers are unlimited since int's become long's when they are too large. However, you can set MAXCNT to a very large value, so that your program only stops in the 22th century.


Here's the code I alluded to yesterday...

import sys, pygame, math


xpos = 92
ypos = 0
gravity = 9.8
velocity = 0
# How much of the velocity of the ball is retained on a bounce
bounce = 0.8
win_h = 400

screen = pygame.display.set_mode((200, win_h), 0, 32)
ball = pygame.image.load('box.bmp')
clock = pygame.time.Clock()
size_bott = ball.get_rect().bottom

# The main loop
while True:
    # Test for exit
    for event in pygame.event.get():
        if event.type == pygame.QUIT:

    # The physics
    # Reverse velocity taking into account bounciness if we hit the ground
    if ypos >= (win_h - size_bott) and velocity > 0:
        # Avoid the ball sinking into the ground
        ypos = (win_h - size_bott)
        velocity = -velocity * bounce

    time_passed = clock.tick(60) / 1000.0
    newvelocity = velocity + (gravity * time_passed)
    # Use the average velocity over the period of the frame to change position
    ypos = ypos + int(((velocity + newvelocity) / 2) * time_passed * 160)
    velocity = newvelocity

    # Update the screen
    screen.fill((0, 0, 0))
    screen.blit(ball, (xpos, ypos))

The only change I made was to account for the height of the "box.bmp" dynamically since it was hard coded as 16 pixels before...


Thanks you very much! I understand the code now; I can't do "(ballSpeed[1]/4*3)", but in order for it to work, I must create separate variables for the numbers: "ypos = ypos + int(((velocity + newvelocity) / 2) * time_passed * 160)". A little bit longer math, but it's worth it! Thanks!


For completeness' sake be sure to let us know how you've implemented your changes once you get it working satisfactorily.


I'm still working on it, but I am working on including some code that will let you drag the ball around and throw it (hopefully more than just on the Y axis) and a Tk window that will let you change the gravity, ball weight, etc.

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