Hit Flash

Part of the Sound and Game Feel section of Coddy's Pygame journey. Lesson 13 of 23.

When you hit an enemy, the game should show it at once, even before a health bar changes. The usual way is a hit flash: for a few frames the enemy is drawn all white.

It takes one counter, the frames left to flash. A hit sets it; each frame lowers it:

flash = 0
...
# a hit
hp -= 1
flash = 6
...
# every frame
if flash > 0:
    flash -= 1

When drawing, the counter picks the colour:

if flash > 0:
    pygame.draw.rect(screen, (255, 255, 255), enemy)
else:
    pygame.draw.rect(screen, (220, 80, 80), enemy)

Six frames is a tenth of a second: long enough to see, short enough that the next hit can flash again. The player can tell at a glance that the attack landed.

A sprite with an image can flash the same way: keep a white copy of its image, or fill a copy with white, and blit that while the counter runs. Many games flash the player red when they take damage, with the same counter.

Challenge

Easy

Space hits the red enemy and lowers its HP. Make each hit flash:

Make flash = 0 before the loop.
On a hit, set flash = 6.
Each frame, lower flash by 1 while it is above 0.
Draw the enemy white (255, 255, 255) while flash is above 0, red otherwise.

Try it yourself

import pygame

pygame.init()
screen = pygame.display.set_mode((480, 360))
pygame.display.set_caption("Training Dummy")
clock = pygame.time.Clock()
font = pygame.font.Font(None, 32)

hit_sound = pygame.mixer.Sound("assets/sounds/hit.ogg")
player = pygame.Rect(120, 150, 60, 60)
enemy = pygame.Rect(300, 150, 60, 60)
hp = 5

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN and event.key == pygame.K_SPACE and hp > 0:
            hp -= 1
            hit_sound.play()

    screen.fill((30, 30, 46))
    pygame.draw.rect(screen, (80, 160, 255), player)
    if hp > 0:
        pygame.draw.rect(screen, (220, 80, 80), enemy)
    label = font.render(f"Enemy HP: {hp}", True, (240, 240, 240))
    screen.blit(label, (300, 110))
    pygame.display.flip()
    clock.tick(60)

pygame.quit()