Lesson 14: Handling Player Input

Topics Covered:

• Detecting keyboard input in Pygame
• Moving objects based on key presses
• Basic game loop structure

Detecting Keyboard Input

Pygame lets you detect when keys are pressed or released using event handling.

for event in pygame.event.get():
    if event.type == pygame.KEYDOWN:
        if event.key == pygame.K_LEFT:
            print("Left arrow pressed")
        elif event.key == pygame.K_RIGHT:
            print("Right arrow pressed")

Moving an Object with the Keyboard

import pygame
import sys

pygame.init()

width, height = 640, 480
screen = pygame.display.set_mode((width, height))
pygame.display.set_caption("Move the Square")

x, y = 300, 220  # Starting position
speed = 5        # Movement speed
square_size = 50

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

    keys = pygame.key.get_pressed()
    if keys[pygame.K_LEFT]:
        x -= speed
    if keys[pygame.K_RIGHT]:
        x += speed
    if keys[pygame.K_UP]:
        y -= speed
    if keys[pygame.K_DOWN]:
        y += speed

    screen.fill((0, 0, 0))  # Clear screen with black
    pygame.draw.rect(screen, (0, 255, 0), (x, y, square_size, square_size))  # Draw square
    pygame.display.flip()  # Update screen

pygame.quit()
sys.exit()

Activity: Control the Square

• Use arrow keys to move the square around the window
• Try changing the speed and size of the square
• Prevent the square from moving outside the window edges (challenge)