import pygame, sys, os
from pygame.locals import *

# Initialize all Pygame modules.
pygame.init( )

# Sets up a window 640x480. Returns a surface, in this case, the surface we will use as the display.
Screen = pygame.display.set_mode( ( 640, 480 ), HWSURFACE | DOUBLEBUF )
# Sets the title to "Simple Draw".
pygame.display.set_caption( 'Simple Draw' )

Drawing = 0

def DrawPixels( ):
	if Drawing == 1:
		BeginPos = pygame.mouse.get_pos( )
		SincePos = pygame.mouse.get_rel( )
		EndPos = ( BeginPos[0] + SincePos[0], BeginPos[1] + SincePos[1] )
		
		pygame.draw.aaline( Screen, ( 255, 255, 255 ), BeginPos, EndPos )	
		pygame.display.flip( )
	
def input( events ):
	for event in events:
		if event.type == QUIT:
			sys.exit( 0 );
		if event.type == MOUSEBUTTONDOWN:
			Drawing = 1
		if event.type == MOUSEBUTTONUP:
			Drawing = 0
			
# Basic Input Loop
while True:
	input( pygame.event.get( ) )
	DrawPixels( )