使用Python和pygame进行矩形碰撞检测

Question

import pygame
import random

red = [255,0,0]
green = [0,255,0]
blue = [0,0,255]
white = [255,255,255]
black = [0,0,0]
UP = [0,-1]
DOWN = [0,1]
LEFT = [-1,0]
RIGHT = [1,0]
NOTMOVING = [0,0]
#constants end
#classes
class collidable:
    x = 0
    y = 0
    w = 0
    h = 0
    rect = pygame.Rect(x,y,w,h)
    color = [0,0,0]
    def __init__(self,x,y,w,h,color):
        self.x = x
        self.y = y
        self.w = w
        self.h = h
        self.color = color
        self.rect = pygame.Rect(x,y,w,h)
    def draw(self):
        pygame.draw.rect(screen,self.color,[self.x,self.y,self.w,self.h],6)

class player:
    x = 0
    y = 0
    speed = 0
    rect = pygame.Rect(x,y,x+20,y+20)
    def __init__(self,x,y,speed):
        self.x = x
        self.y = y
        self.speed = speed
        self.rect = pygame.Rect(self.x,self.y,self.x+20,self.y+20)
    def draw(self):
        if player_moving==LEFT:
        pygame.draw.polygon(screen,black,[(self.x-10,self.y),(self.x+10,self.y-10),(self.x+10,self.y+10)])
        elif player_moving==RIGHT:
            pygame.draw.polygon(screen,black,[(self.x+10,self.y),(self.x-10,self.y-10),(self.x-10,self.y+10)])
        elif player_moving==UP:
            pygame.draw.polygon(screen,black,[(self.x,self.y-10),(self.x+10,self.y+10),(self.x-10,self.y+10)])
        elif player_moving==DOWN:
            pygame.draw.polygon(screen,black,[(self.x,self.y+10),(self.x+10,self.y-10),(self.x-10,self.y-10)])
        else:
            pygame.draw.rect(screen,black,pygame.Rect(self.x-10,self.y-10,20,20),6)
    def setpos(self,x,y):
        self.x = x
        self.y = y
    def move(self,direction):
        self.x = self.x + direction[0]*self.speed
        self.y = self.y + direction[1]*self.speed
#classes end

#globals
pygame.init()
screenSize = [800,600]
screenBGColor = white
screen=pygame.display.set_mode(screenSize)
pygame.display.set_caption("Move the Block")
player = player(screenSize[0]/2,screenSize[1]/2,9)
collidables = []
clock=pygame.time.Clock()
for i in range(10):
    collidables.append(collidable(random.randrange(0,screenSize[0]),random.randrange(0,screenSize[1]),random.randrange(10,200),random.randrange(10,200),blue))

running = True
#globals end

#functions
def render():
    screen.fill(screenBGColor)
    clock.tick(60)
    player.draw()
    for c in collidables:
        c.draw()
    pygame.display.flip()
def tick():                                           #----------------HERE
    for c in collidables:
        if player.rect.colliderect(c.rect):
            player_moving = NOTMOVING
            print("hit")
    player.move(player_moving)

#functions end

#main loop
while running==True:
    for event in pygame.event.get():
        if event.type==pygame.QUIT:
            running = False
        if event.type==pygame.KEYDOWN:
            if event.key==pygame.K_LEFT:
                player_moving = LEFT
            if event.key==pygame.K_RIGHT:
                player_moving = RIGHT
            if event.key==pygame.K_UP:
                player_moving = UP
            if event.key==pygame.K_DOWN:
                player_moving = DOWN
        else:
            player_moving = NOTMOVING
    tick()
    render()
#main loop end

pygame.quit()

我正在尝试制作一个简单的碰撞检测，以在接触可碰撞对象时禁用玩家移动。但无论可碰撞对象位于何处，碰撞都会被触发。我不知道为什么玩家不会移动，这段代码应该只在玩家中心距离可碰撞对象边界10像素时阻止移动。我确信这种方法是错误的，但我想不到其他检查碰撞的方法。

- Kroltan

---

你正在阅读这本书吗：http://inventwithpython.com/？ - yati sagade

你真的指望我们为你调试程序吗？:o - mac

抱歉，我不是那个意思。我确定代码有问题，我需要更好的碰撞检测方法。我的帖子缺少这个，因为我最近的网络速度非常慢，当我不小心按下回车键发送时，它没有取消。 - Kroltan

将 print("hit") 转换为 print("hit")，以查看命中发生的位置（并查看是否不正确）。您的代码似乎很好。 - A.H

@A.H 对不起，我没明白。我是Python的新手，你说的"transforming"是什么意思？ - Kroltan

我的答案对你没用吗？ - A.H

Answer 1

你正在探究所谓的AABB（轴对齐边界框）。你会在角色周围设置一个框，以便检测周围的物体。

以下是一些资源，可能会帮助你了解情况，并提供更好的实现技巧：

http://www.gamasutra.com/view/feature/3426/when_two_hearts_collide_.php

http://www.gamefromscratch.com/post/2012/11/26/GameDev-math-recipes-Collision-detection-using-an-axis-aligned-bounding-box.aspx

其他各种平台实现

阅读这些！我曾经在碰撞检测方面挣扎了一段时间，这些确实很有帮助。

- Rhompus

Answer 2

好的，基本上，你是对的。你的程序很好，但是：

• 在pygame文档中： 矩形 = (PosX，PosY，宽度，高度)

所以，你的代码（差异）：

- self.rect = pygame.Rect(self.x,self.y,self.x+20,self.y+20)
+ self.rect = pygame.Rect(self.x,self.y,self.20,self.20)

还有：

  def move(self,direction):
      self.x = self.x + direction[0]*self.speed
      self.y = self.y + direction[1]*self.speed
+     self.rect = pygame.Rect(self.x,self.y,self.20,self.20)

你的代码还有一个小问题。例如，在你的 tick() 函数中，你使用了 player_moving，但是在第一次迭代中，这个变量根本不存在。

以下是可以运行的代码：

import pygame
import random

red = [255,0,0]
green = [0,255,0]
blue = [0,0,255]
white = [255,255,255]
black = [0,0,0]
UP = [0,-1]
DOWN = [0,1]
LEFT = [-1,0]
RIGHT = [1,0]
NOTMOVING = [0,0]
#constants end
#classes
class collidable:
    x = 0
    y = 0
    w = 0
    h = 0
    rect = pygame.Rect(x,y,w,h)
    color = [0,0,0]
    def __init__(self,x,y,w,h,color):
        self.x = x
        self.y = y
        self.w = w
        self.h = h
        self.color = color
        self.rect = pygame.Rect(x,y,w,h)
    def draw(self):
        pygame.draw.rect(screen,self.color,[self.x,self.y,self.w,self.h],6)

class player:
    x = 0
    y = 0
    speed = 0
    rect = pygame.Rect(x,y,20,20)
    def __init__(self,x,y,speed):
        self.x = x
        self.y = y
        self.speed = speed
        self.rect = pygame.Rect(self.x,self.y,20,20)
    def draw(self):
        if player_moving==LEFT:
                pygame.draw.polygon(screen,black,[(self.x-10,self.y),(self.x+10,self.y-10),(self.x+10,self.y+10)])
        elif player_moving==RIGHT:
            pygame.draw.polygon(screen,black,[(self.x+10,self.y),(self.x-10,self.y-10),(self.x-10,self.y+10)])
        elif player_moving==UP:
            pygame.draw.polygon(screen,black,[(self.x,self.y-10),(self.x+10,self.y+10),(self.x-10,self.y+10)])
        elif player_moving==DOWN:
            pygame.draw.polygon(screen,black,[(self.x,self.y+10),(self.x+10,self.y-10),(self.x-10,self.y-10)])
        else:
            pygame.draw.rect(screen,black,pygame.Rect(self.x-10,self.y-10,20,20),6)
    def setpos(self,x,y):
        self.x = x
        self.y = y
    def move(self,direction):
        self.x = self.x + direction[0]*self.speed
        self.y = self.y + direction[1]*self.speed
        self.rect = pygame.Rect(self.x,self.y,20,20)
#classes end

#globals
pygame.init()
screenSize = [800,600]
screenBGColor = white
screen=pygame.display.set_mode(screenSize)
pygame.display.set_caption("Move the Block")
player = player(screenSize[0]/2,screenSize[1]/2,9)
collidables = []
clock=pygame.time.Clock()
for i in range(10):
    collidables.append(collidable(random.randrange(0,screenSize[0]),random.randrange(0,screenSize[1]),random.randrange(10,200),random.randrange(10,200),blue))

running = True
#globals end
player_moving = NOTMOVING
#functions
def render():
    screen.fill(screenBGColor)
    clock.tick(60)
    player.draw()
    for c in collidables:
        c.draw()
    pygame.display.flip()
def tick(player_moving):                                           #----------------HERE
    for c in collidables:
        if player.rect.colliderect(c.rect):
            player_moving = NOTMOVING
            print("hit"+str(c.rect)+" with "+str(player.rect))
    player.move(player_moving)

#functions end

#main loop
while running==True:
    for event in pygame.event.get():
        if event.type==pygame.QUIT:
            running = False
        if event.type==pygame.KEYDOWN:
            if event.key==pygame.K_LEFT:
                player_moving = LEFT
            if event.key==pygame.K_RIGHT:
                player_moving = RIGHT
            if event.key==pygame.K_UP:
                player_moving = UP
            if event.key==pygame.K_DOWN:
                player_moving = DOWN
        else:
            player_moving = NOTMOVING
    tick(player_moving)
    render()
#main loop end

pygame.quit()

- A.H