如何在发生碰撞时显示爆炸图像？

Question

我不知道为什么没有发生爆炸效果。
其他图都画得很好，唯独爆炸图不行

explosion = pygame.image.load(os.path.join(image_path, "explosion.png"))
explosion_size = explosion.get_rect().size
explosion_width = explosion_size[0]

for missile_idx, missile_val in enumerate(missiles):
    missile_pos_x = missile_val[0]
    missile_pos_y = missile_val[1]

    #weapon information upgrade
    missile_rect = missile.get_rect()
    missile_rect.left = missile_pos_x
    missile_rect.top = missile_pos_y

    if missile_rect.colliderect(rock_rect):
        explosion_sound.play()
        **explosion_pos_x = missile_pos_x
        explosion_pos_y = missile_pos_y
        screen.blit(explosion,(explosion_pos_x,explosion_pos_y))**
        del(rock)
        del(missiles)
        missiles = []

        # missile position coordination
        missiles = [[m[0], m[1] - missile_speed] for m in missiles]

        # top missile elimination
        missiles = [[m[0], m[1]] for m in missiles if m[1]>0]

Answer 1

爆炸只显示一小会儿。使用

pygame.time.get_ticks()

返回自调用

pygame.init()

以来的毫秒数。计算必须删除爆炸图像之后的时间点。将爆炸的坐标和结束时间点添加到列表的头部 (

explosionList 

)。在主应用程序循环中绘制爆炸。从列表尾部删除过期的爆炸：

explosionList = []

while run:
    current_time = pygame.time.get_ticks()
    # [...]

    for missile_idx, missile_val in enumerate(missiles)
        # [...]

        if missile_rect.colliderect(rock_rect):
            explosion_sound.play()

            explosion_pos_x = missile_pos_x
            explosion_pos_y = missile_pos_y
            end_time = current_time + 2000 # 2000 milliseconds = 2 seconds
            explosionList.insert(0, (end_time, explosion_pos_x, explosion_pos_y))

            # [...]

    for i in range(len(explosionList)):
        if current_time < explosionList[i][0]:
            screen.blit(explosion, (explosionList[i][1], explosionList[i][2]))
        else:
            explosionList = explosionList[:i]
            break
    
    # [...]

使用此算法可以管理多次爆炸。

参见时间、定时器事件和时钟

---

最小示例 PYGBAG 演示

import pygame
pygame.init()
window = pygame.display.set_mode((210, 210))

def create_rectangles():
    global rectangles
    w, h = window.get_size()
    rectangles = []
    for x in range(0, w - 60, 60):
        for y in range(0, h - 60, 60):
            rectangles.append(pygame.Rect(x + 30, y + 30, 30, 30))

create_rectangles()
hit_list = []
fade_out_time = 3000

run = True
while run:
    current_time = pygame.time.get_ticks()
    
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

    point = pygame.mouse.get_pos()
    collideindex = pygame.Rect(point, (1, 1)).collidelist(rectangles)
    if collideindex >= 0:
        end_time = current_time + fade_out_time
        hit_list.insert(0, (end_time, rectangles[collideindex].center))
        del rectangles[collideindex]
    if not hit_list and not rectangles:
        create_rectangles()

    window.fill(0)
    for r in rectangles:
        pygame.draw.rect(window, (255, 0, 0), r)
    for i in range(len(hit_list)):
        delta_time = hit_list[i][0] - current_time
        if delta_time > 0:
            radius = round(30 * delta_time / fade_out_time)
            pygame.draw.circle(window, (255, 255, 0), hit_list[i][1], radius)
        else:
            hit_list = hit_list[:i]
            break
    pygame.display.flip()

Answer 2

如果你想显示爆炸图像一段时间，这个方法可能很有用。

explosion_list = [] # list for explosion effect
running = True
while running:
     start_time = pygame.time.get_ticks() # add time for explosion effect

     for missile_idx, missile_val in enumerate(missiles):
         missile_pos_x = missile_val[0]
         missile_pos_y = missile_val[1]

         #weapon information upgrade
         missile_rect = missile.get_rect()
         missile_rect.left = missile_pos_x
         missile_rect.top = missile_pos_y

         if missile_rect.colliderect(rock_rect):
             explosion_sound.play()
             explosion_pos_x = missile_pos_x
             explosion_pos_y = missile_pos_y
             explosion_time = start_time + 2000 # 1000 milliseconds = 2 seconds
             **explosion_list.insert(0, (explosion_time, explosion_pos_x, explosion_pos_y))**
             del(rock)
             del(missiles)
             missiles = []
            
             # missile position coordination
             missiles = [[m[0], m[1] - missile_speed] for m in missiles]

             # top missile elimination
             missiles = [[m[0], m[1]] for m in missiles if m[1]>0]
                        
             **for i in range(len(explosion_list)):
                 if start_time < explosion_time:
                    pygame.display.update()
                    screen.blit(explosion, (explosion_pos_x - 30, explosion_pos_y - 30))
                    pygame.time.delay(10)**
                    else:
                         explosion_list = explosion_list[:i]