pygame function appears to be being ignored
Question
I'm building a relatively simple programme to test collision detection, it's all working fine at the moment except one thing, I'm trying to make the background colour change randomly, the only issue is that it appears to be completely skipping the function to do this;
import pygame
from pygame.locals import *
import random, math, time, sys
pygame.init()
Surface = pygame.display.set_mode((800,600))
backgroundr = int(random.random()*255)+1
backgroundg = int(random.random()*255)+1
backgroundb = int(random.random()*255)+1
Circles = []
class Circle:
def __init__(self):
self.radius = int(random.random()*50) + 1
self.x = random.randint(self.radius, 800-self.radius)
self.y = random.randint(self.radius, 600-self.radius)
self.speedx = 0.5*(random.random()+1.0)
self.speedy = 0.5*(random.random()+1.0)
self.r = int(random.random()*255)+1
self.g = int(random.random()*255)+1
self.b = int(random.random()*255)+1
## self.mass = math.sqrt(self.radius)
for x in range(int(random.random()*30) + 1):
Circles.append(Circle())
def CircleCollide(C1,C2):
C1Speed = math.sqrt((C1.speedx**2)+(C1.speedy**2))
XDiff = -(C1.x-C2.x)
YDiff = -(C1.y-C2.y)
if XDiff > 0:
if YDiff > 0:
Angle = math.degrees(math.atan(YDiff/XDiff))
XSpeed = -C1Speed*math.cos(math.radians(Angle))
YSpeed = -C1Speed*math.sin(math.radians(Angle))
elif YDiff < 0:
Angle = math.degrees(math.atan(YDiff/XDiff))
XSpeed = -C1Speed*math.cos(math.radians(Angle))
YSpeed = -C1Speed*math.sin(math.radians(Angle))
elif XDiff < 0:
if YDiff > 0:
Angle = 180 + math.degrees(math.atan(YDiff/XDiff))
XSpeed = -C1Speed*math.cos(math.radians(Angle))
YSpeed = -C1Speed*math.sin(math.radians(Angle))
elif YDiff < 0:
Angle = -180 + math.degrees(math.atan(YDiff/XDiff))
XSpeed = -C1Speed*math.cos(math.radians(Angle))
YSpeed = -C1Speed*math.sin(math.radians(Angle))
elif XDiff == 0:
if YDiff > 0:
Angle = -90
else:
Angle = 90
XSpeed = C1Speed*math.cos(math.radians(Angle))
YSpeed = C1Speed*math.sin(math.radians(Angle))
elif YDiff == 0:
if XDiff < 0:
Angle = 0
else:
Angle = 180
XSpeed = C1Speed*math.cos(math.radians(Angle))
YSpeed = C1Speed*math.sin(math.radians(Angle))
C1.speedx = XSpeed
C1.speedy = YSpeed
C1.r = int(random.random()*255)+1
C1.g = int(random.random()*255)+1
C1.b = int(random.random()*255)+1
C2.r = int(random.random()*255)+1
C2.g = int(random.random()*255)+1
C2.b = int(random.random()*255)+1
def ColourCheck():
checknumber = int(random.random()*50)+1
if checknumber == 50:
backgroundr = int(random.random()*255)+1
backgroundg = int(random.random()*255)+1
backgroundb = int(random.random()*255)+1
def Move():
for Circle in Circles:
Circle.x += Circle.speedx
Circle.y += Circle.speedy
def CollisionDetect():
for Circle in Circles:
if Circle.x < Circle.radius or Circle.x > 800-Circle.radius:
Circle.speedx *= -1
Circle.r = int(random.random()*255)+1
Circle.g = int(random.random()*255)+1
Circle.b = int(random.random()*255)+1
if Circle.y < Circle.radius or Circle.y > 600-Circle.radius:
Circle.speedy *= -1
Circle.r = int(random.random()*255)+1
Circle.g = int(random.random()*255)+1
Circle.b = int(random.random()*255)+1
for Circle in Circles:
for Circle2 in Circles:
if Circle != Circle2:
if math.sqrt( ((Circle.x-Circle2.x)**2) + ((Circle.y-Circle2.y)**2) ) <= (Circle.radius+Circle2.radius):
CircleCollide(Circle,Circle2)
def Draw():
Surface.fill((backgroundr,backgroundg,backgroundb))
for Circle in Circles:
pygame.draw.circle(Surface,(Circle.r,Circle.g,Circle.b),(int(Circle.x),int(600-Circle.y)),Circle.radius)
pygame.display.flip()
def GetInput():
keystate = pygame.key.get_pressed()
for event in pygame.event.get():
if event.type == QUIT or keystate[K_ESCAPE]:
pygame.quit(); sys.exit()
def main():
while True:
ColourCheck()
GetInput()
Move()
CollisionDetect()
Draw()
if __name__ == '__main__': main()
it's the ColourCheck
function that's being ignored, any ideas why?
Solution
I believe backgroundr, backgroundg, and backgroundb are local variables to your ColourCheck() function.
If you're determined to use global variables, try this at the top of your file:
global backgroundr;
global backgroundg;
global backgroundb;
backgroundr = int(random.random()*255)+1
backgroundg = int(random.random()*255)+1
backgroundb = int(random.random()*255)+1
and this in your function:
def ColourCheck():
global backgroundr;
global backgroundg;
global backgroundb;
checknumber = int(random.random()*50)+1
if checknumber == 50:
backgroundr = int(random.random()*255)+1
backgroundg = int(random.random()*255)+1
backgroundb = int(random.random()*255)+1
OTHER TIPS
Move()
, CollisionDetect()
, and Draw()
all refer to Circles
, but don't declare it global. Try adding a global Circles
line to the beginning of each function. Also, I'd recommend changing your variables to lower-case; not only does an initial cap typically indicate a class in Python, but you're actually generating (insignificant) collisions between the Circle
variable and the Circle
class.
For example:
circles = []
# ...
for x in range(int(random.random()*30) + 1):
circles.append(Circle())
# ...
def Move():
global circles
for circle in circles:
circle.x += circle.speedx
circle.y += circle.speedy
# ...
Edit:
And as Nathan notes, your backgroundX
variables also need to be declared global in ColorCheck()
and Draw()
.
You might consider wrapping all of these functions into a Game
class (or some such), to avoid working with so many globals.