首页 > 解决方案 > 我可以让一个函数在一个列表中返回多个值吗?

问题描述

这是我的圈子课:

class circle:
    def __init__(self):
        self.x = random.randint(10, SW-10)
        self.y = random.randint(10, SH-10)
        self.radius = random.randint(5, 50)
        self.color =  (random.randint(1, 255),random.randint(1, 255), random.randint(1, 255))

    def draw(self):
        pygame.draw.circle(d, (self.color), (self.x, self.y), self.radius)

    def move(self):
        self.x = X
        self.y = Y

在这个圈子课程中,我通过做一个用户圈子user = circle()和通过做 20 个随机圈子

circles = list()
for i in range(20):
   circles.append(circle())`

这是我的cilsion检测:

def circle_collision(cir1, cir2):
    a = abs(cir2.x - cir1.x)**2
    b = abs(cir2.y - cir1.y)**2
    distance = math.sqrt((a) + (b))
    if  distance < cir1.radius + cir2.radius:
        return True
    else:
        return False

我的问题是我不能将列表circles作为我的碰撞检测参数之一传递,但我也希望程序检测user = circle()圆何时与任何其他随机圆发生碰撞。最初,我尝试这样做来解决我的问题:

def foo():
    for i in range(len(circles)):
        result = circles[i]
    return result

while True我希望这能返回列表中的每个项目,这样我就可以在循环内调用碰撞检测,如下所示:

collided = circle_collision(user, foo())

但是该foo函数只返回一个值,因此碰撞检测只能检测到一个圆圈。我该怎么做才能collision_detection检查每个圆圈?有没有办法让函数返回多个值?还是我必须完全改变我的逻辑?感谢您的帮助。

这是我的整个程序供参考。

import pygame, math, os, random

os.environ["SDL_VIDEO_CENTERED"]="1"
pygame.init()

win = pygame.display
win.set_caption("A lot a circles")
SW = 1200
SH = 600
d = win.set_mode((SW, SH))
pygame.time.Clock().tick(60)

def write(size, text, x, y):
    font = pygame.font.SysFont("Aeiral", size)
    text = font.render(text, True, (0, 0, 0))
    d.blit(text, (x, y))

def circle_collision(cir1, cir2):
    a = abs(cir2.x - cir1.x)**2
    b = abs(cir2.y - cir1.y)**2
    distance = math.sqrt((a) + (b))
    if  distance < cir1.radius + cir2.radius:
        return True
    else:
        return False

class circle:
    def __init__(self):
        self.x = random.randint(10, SW-10)
        self.y = random.randint(10, SH-10)
        self.radius = random.randint(5, 50)
        self.color =  (random.randint(1, 255),random.randint(1, 255), random.randint(1, 255))

    def draw(self):
        pygame.draw.circle(d, (self.color), (self.x, self.y), self.radius)

    def move(self):
        self.x = X
        self.y = Y

user = circle()

def foo():
    for i in range(len(circles)):
        result = circles[i]
    return result

circles = list()
for i in range(20):
   circles.append(circle())

mainloop = True
while mainloop:
    X, Y = pygame.mouse.get_pos()
    d.fill((98, 98, 98))
    for i in circles:
        i.draw()
    user.draw()
    user.move()
    write(user.radius, "USER", user.x - user.radius + 2, user.y - 7)
    collided = circle_collision(user, foo())
    if collided == True:
        user.color = (255, 0, 0)
    if collided == False:
        user.color = (255, 255, 255)

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            mainloop = False

    win.flip()

pygame.quit()
quit()

标签: pythonlistpygame

解决方案


您必须添加另一个函数,该函数评估一个圆是否与列表中的一个圆发生碰撞,并使用碰撞的圆创建一个新列表:

def circles_collision(cir1, cirlist):
    collidlist = []
    for cir2 in cirlist:
        if circle_collision(cir1, cir2):
            collidlist.append(cir2)
    return collidlist

甚至更短:

def circles_collision(cir1, cirlist):
    return [cir2 for cir2 in cirlist if circle_collision(cir1, cir2)]

测试是否collidelistany元素:

collidelist = circles_collision(user, circles)
if any(collidelist):
    user.color = (255, 0, 0)
else:
    user.color = (255, 255, 255) 

如果您只想评估是否有任何圆圈发生碰撞,那么您根本不需要列表和单独的函数:

if any(circle_collision(user, circle) for circle in circles):  
    user.color = (255, 0, 0)
else:
    user.color = (255, 255, 255)

推荐阅读