Arrow Keys

Lesson 5 of 40 in Coddy's Make Games with Pygame course.

To move the square, keep its position in variables and draw it there every frame. Change the variables and the next frame shows the square somewhere else.

pygame.key.get_pressed() tells you which keys are held down right now. Index it with a key constant such as pygame.K_RIGHT: the result is True while that key is down.

x = 100

while running:
    # events
    keys = pygame.key.get_pressed()
    if keys[pygame.K_RIGHT]:
        x += 4
    # fill, then draw at x

Hold Right and the square moves 4 pixels in every frame, 240 pixels a second at 60 frames a second. The arrow keys are K_LEFT, K_RIGHT, K_UP and K_DOWN. Up means a smaller y.

Make the variables before the loop. A variable set inside the loop starts over on every frame.

Challenge

Easy

Move the square with the arrow keys:

Before the loop, make x, y = 220, 160 and speed = 4.
In the loop, after the events, read the keys with pygame.key.get_pressed(). Each held arrow changes x or y by speed.
Draw the square at (x, y, 40, 40).

Try it yourself

import pygame

pygame.init()
screen = pygame.display.set_mode((480, 360))
pygame.display.set_caption("Move the Square")
clock = pygame.time.Clock()

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    screen.fill((30, 30, 46))
    pygame.draw.rect(screen, (255, 196, 0), (220, 160, 40, 40))
    pygame.display.flip()
    clock.tick(60)

pygame.quit()