pygame - How to detect touch screen clicks in python?

Question

How can I detect if an image has been touched in pygame on a touch screen? I have searched but I can not find how to detect if a particular image is touched.

Answer 1

To detect if an image has been touched, you can use the MOUSEBUTTONDOWN event. See Pygame mouse clicking detection.

Load the image with pygame.image.load(). Crate the bounding rectangle (pygame.Rect). Create a pygame.Mask from the image with pygame.mask.from_surface:

image = pygame.image.load('image.png').convert_alpha()
image _rect = image.get_rect(topleft = (x, y))
image_mask = pygame.mask.from_surface(image)

Use the MOUSEBUTTONDOWN event to detect if the mouse is clicked in the rectangular area of the image. Check if the corresponding bit in the image mask is set:

for event in pygame.event.get():
    if event.type == pygame.MOUSEBUTTONDOWN:
        image_x, image_y = event.pos[0] - image_rect.x, event.pos[1] - image_rect.y
        if image_rect.collidepoint(event.pos) and image_mask.get_at((image_x, image_y)):
            print("touched")

---

Minimal example:

import pygame

pygame.init()
window = pygame.display.set_mode((400, 400))
font = pygame.font.SysFont(None, 100)
clock = pygame.time.Clock()
text = font.render("Text", True, (255, 255, 0))

bomb = pygame.image.load('Bomb-256.png').convert_alpha()
bomb_rect = bomb.get_rect(center = window.get_rect().center)
bomb_mask = pygame.mask.from_surface(bomb)
click_count = 0
click_text = font.render('touch: ' + str(click_count), True, "black")

run = True
while run:
    clock.tick(60)
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False 
        if event.type == pygame.MOUSEBUTTONDOWN:
            image_x, image_y = event.pos[0] - bomb_rect.x, event.pos[1] - bomb_rect.y
            if bomb_rect.collidepoint(event.pos) and bomb_mask.get_at((image_x, image_y)):
                click_count += 1
                click_text = font.render('touch: ' + str(click_count), True, "black")

    window.fill((255, 255, 255))
    window.blit(bomb, bomb_rect)
    window.blit(click_text, click_text.get_rect(topleft = (20, 20)))
    pygame.display.flip()

pygame.quit()
exit()