# import pygame module in this program
import pygame
# activate the pygame library .
# initiate pygame and give permission
# to use pygame's functionality.
pygame.init()
# create the display surface object
# of specific dimension..e(500, 500).
win = pygame.display.set_mode((500, 500))
# set the pygame window name
pygame.display.set_caption("Moving rectangle")
# object current co-ordinates
x = 200
y = 200
# dimensions of the object
width = 20
height = 20
# velocity / speed of movement
vel = 10
# Indicates pygame is running
run = True
# infinite loop
while run:
# creates time delay of 10ms
pygame.time.delay(10)
# iterate over the list of Event objects
# that was returned by pygame.event.get() method.
for event in pygame.event.get():
# if event object type is QUIT
# then quitting the pygame
# and program both.
if event.type == pygame.QUIT:
# it will make exit the while loop
run = False
# stores keys pressed
keys = pygame.key.get_pressed()
# if left arrow key is pressed
if keys[pygame.K_LEFT] and x>0:
# decrement in x co-ordinate
x -= vel
# if left arrow key is pressed
if keys[pygame.K_RIGHT] and x<500-width:
# increment in x co-ordinate
x += vel
# if left arrow key is pressed
if keys[pygame.K_UP] and y>0:
# decrement in y co-ordinate
y -= vel
# if left arrow key is pressed
if keys[pygame.K_DOWN] and y<500-height:
# increment in y co-ordinate
y += vel
# completely fill the surface object
# with black colour
win.fill((0, 0, 0))
# drawing object on screen which is rectangle here
pygame.draw.rect(win, (255, 0, 0), (x, y, width, height))
# it refreshes the window
pygame.display.update()
# closes the pygame window
pygame.quit()