#!/usr/bin/env python
import pygame
import sys # needed to quit gracefully
#import pygame.draw
N_PIXELS_TO_MOVE = 5 # how many pixels to
move on each keypress
FRAMES_PER_SECOND = 30 # How fast to draw -
this says draw every 30th of a second
def main():
pygame.init()
clock = pygame.time.Clock() # added to
allow things to slow down
screen = pygame.display.set_mode((640,
480))
pygame.display.set_caption('pygame
test')
# You don't need this. screen.fill
below does this for you.
#s = pygame.Surface(screen.get_size(),
pygame.SRCALPHA, 32)
# Pick a starting X, Y location for the
circle
circleX = 0
circleY = 0
while True:
# You don't need this
#screen.blit(s, (0, 0))
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit() # quit pygame
sys.exit() # quit the
program
if event.type == pygame.KEYDOWN:
if event.key ==
pygame.K_ESCAPE or event.unicode == 'q':
pygame.quit()
sys.exit()
# If user presses left,
right, up, or down, change the appropriate coordinate
elif event.key ==
pygame.K_LEFT:
circleX = circleX -
N_PIXELS_TO_MOVE
elif event.key ==
pygame.K_RIGHT:
circleX = circleX +
N_PIXELS_TO_MOVE
elif event.key ==
pygame.K_UP:
circleY = circleY -
N_PIXELS_TO_MOVE
elif event.key ==
pygame.K_DOWN:
circleY = circleY +
N_PIXELS_TO_MOVE
# Now do all the drawing, first the
background (fill)
screen.fill((0, 0, 0))
# Then draw the circle at the
circle's coordinates
pygame.draw.circle(screen, (255,
255, 255, 255), (circleX, circleY), 50)
pygame.display.flip() # or:
pygame.display.update()
clock.tick(FRAMES_PER_SECOND) #
make PyGame wait the correct amount
if __name__ == '__main__':
main()