Question

Basically, I’ve wanted to get back into Python, so I decided to make a small game in pygame, where there is a bouncy ball which you need to keep bouncing in the air. The problem is that when I use the functions clock.tick() and clock.get_time(), get_time should return the time passed in milliseconds, but it passes time in milliseconds*10.

My code:

GRAVITY = 10

def move(self, delta):
    self.x+= (self.vx * delta)
    self.y+= (self.vy * delta)

def speed(self, delta):
    self.vy += (GRAVITY * delta)

clock.tick()

while True:
    clock.tick()
    delta = (clock.get_time() / 100) #should be /1000
    ball.move(delta)
    ball.speed(delta)

It works smoothly like in real world when its /100, but works really slow then its /1000.

Answer 1

I think part of the problem might be truncation from dividing by “1000” instead of “1000.0”. You can verify clock.tick is working with this:

import pygame
pygame.init()
i = 0
clock = pygame.time.Clock()
while i < 10: # Just run a few cycles to check the output
    res = clock.tick(1) # Caps framerate to 1 fps
    print res # This should print out 1000
    i += 1

Note that clock.tick already returns the delta and is normally used to cap the framerate. If left uncapped, you might have a really high FPS, giving a small delta and, when divided by an int, isn’t larger than 1 so you rarely get a number at all.

Also, make sure you have all your units right, that you really want to be converting to seconds