为什么此代码仅记录某些冲突而不是全部冲突?

时间:2019-04-22 22:09:52

标签: python pygame collision-detection

嗨,我有一个游戏代码,其中有许多水果从天上掉下来,底部的青蛙必须设法抓住它们。当他抓到一个分数时,分数上升。这仅在青蛙与某些水果而不是所有水果碰撞时才发生。分数在某个点之后无缘无故地随机开始无休止地增加。这是大多数代码,因为我不确定错误将在哪里:

import pygame, sys, time, random
from pygame.locals import *
from math import fabs
######### constants ##########
jumpvel=20
fallingspeed=1
running= True
blue= [129,183 ,253]
pink=[255,174,201]
textcolour= [255,255,255]
x=700//2
y=1000//2
score=0

thingylist= ['fruit1.bmp','fruit2.bmp','fruit3.bmp','fruit4.bmp','fruit5.bmp','fruit1.bmp','fruit2.bmp','fruit3.bmp','fruit4.bmp','fruit5.bmp','naughty1.bmp','naughty2.bmp','naughty3.bmp',]
all_things=[]
for i in range (12):
    new_thing_image=pygame.image.load(thingylist[(random.randrange(0,12))])
    new_thing_image.set_colorkey(pink)
    new_thing_rect=new_thing_image.get_rect()
    new_thing_rect.x=random.randrange(0,950)
    new_thing_rect.y=-random.randrange(50,500)
    all_things.append([new_thing_image,new_thing_rect])

def checkCollision (frog_rect,all_things,score):
    collides_with=None
    for thing_image, thing_rect in all_things:
        if frog_rect.colliderect(thing_rect):
            collides_with=True
    if collides_with == True:
        score= score+100
    return collides_with,score

######## initialising screen#########        
pygame.init()
gamedisplay=pygame.display.set_mode((1000,600)) #making the screen
pygame.display.set_caption('frog')
clock=pygame.time.Clock()# frames per second
bg=pygame.image.load('actual clouds.bmp').convert()


############ initialising sprites##############
frog= pygame.image.load('actual frog.bmp')
frog.set_colorkey(blue)
frog_rect=frog.get_rect()
frog_rect.centerx=(x)
frog_rect.centery=(y)

##########drawing things#############
def drawThings (all_things):
    for item in all_things:
        new_thing_image, new_thing_rect= item
        gamedisplay.blit(new_thing_image, (new_thing_rect.x, new_thing_rect.y))

#########update display function###########
def update(x,y,all_things,score):
    gamedisplay.blit(bg,[0,0])
    gamedisplay.blit(frog,(x,y))
    for thing in range (len(all_things)):
        new_thing_rect=all_things[i][1]
        #thing_rect.y=thing_rect.y+fallingspeed
        new_thing_rect.y+= fallingspeed
    drawThings(all_things)
    label=font.render("score "+ str(score) ,1,textcolour)
    gamedisplay.blit(label,(750,10))
    gamedisplay.blit(heart1,(750,50))
    gamedisplay.blit(heart2,(850,50))
    gamedisplay.blit(heart2,(800,50))
    pygame.display.update()
    pygame.time.delay(50)

while running == True:
    gamedisplay.blit(bg,[0,0])
    gamedisplay.blit(frog,(x,y))
    drawThings(all_things)
    label=font.render("score "+ str(score) ,1,textcolour)
    gamedisplay.blit(label,(750,10))
    pygame.display.flip()
    pygame.event.pump()
    key=pygame.key.get_pressed()
    for item in all_things:
        new_thing_image, new_thing_rect= item
        new_thing_rect.y+= fallingspeed
        if new_thing_rect.y >450:
            new_thing_rect.x=random.randrange(0,950)
            new_thing_rect.y=-random.randrange(50,500)
    ############collision detection##########
    detect,score =checkCollision (frog_rect, all_things,score)

    update(x,y,all_things,score)

分数每次与任何下降的果粒发生碰撞时都应该增加,而不仅仅是某些分数,而不仅仅是开始不停地随机增加。任何帮助将不胜感激谢谢你!

1 个答案:

答案 0 :(得分:0)

基于代码段-该代码段不包含青蛙位置更新代码,因此我认为存在以下问题:

  • 得分随机增加
  • 冲突并不总是有效

这是因为碰撞矩形只为青蛙的起始位置定义了一次,但从未随青蛙的位置变化而更新。

############ initialising sprites##############
frog= pygame.image.load('actual frog.bmp')
frog.set_colorkey(blue)
frog_rect=frog.get_rect()
frog_rect.centerx=(x)       # <-- rect only ever updated here!
frog_rect.centery=(y)

这将导致所描述的症状,因为通过碰撞矩形掉落的得分对象(水果?)会增加得分(看似随机),并且当青蛙仍在其原始位置上方时,碰撞会完美地起作用。如果青蛙部分在直肠上方,它将有些起作用,并且一旦青蛙移开起始位置直肠就完全不起作用。

该问题的解决方案是每当更新青蛙位置的frog_rectx时更新矩形y的坐标。这可以通过在frog_rect.centerx函数中设置frog_rect.centeryupdate()来实现:

def update(x, y, all_things, score ):
    frog_rect.x = x
    frog_rect.y = y

使用.centerx.centery坐标初始化青蛙的rect,但是在x,y绘制青蛙,因此碰撞rect也开始偏离中心。因此,最好也更新初始化函数:

frog_rect=frog.get_rect()
frog_rect.x = x
frog_rect.y = y