乒乓 Racket 移动得如此之快,以至于在检测到碰撞之前,球在 Racket 内盘旋。问题是用户输入将桨移动了一个像素,所以我不知道如何减慢速度。解决方法是什么?这是代码:
import pygame, sys, os
from pygame import*
from pygame.locals import*
WHITE = (255, 255, 255)
GREEN = (0, 255, 0)
BLUE = (0, 0, 128)
RED = (255,0,0)
os.environ["SDL_VIDEO_CENTERED"]="1"
displaysize=600
DISPLAYSURF = pygame.display.set_mode((displaysize,displaysize))
rectwidth = 50
rectheight= 50
rectposx =0
rectposy =0
class Player(object):
def __init__(self):
self.rect = pygame.rect.Rect((rectposx, rectposy, rectwidth, rectheight))
def handle_keys(self):
key = pygame.key.get_pressed()
dist = 1
if key[pygame.K_LEFT] and (player.rect.x>0):
self.rect.move_ip(-1, 0)
if key[pygame.K_RIGHT] and (player.rect.x<600-rectwidth):
self.rect.move_ip(1, 0)
if key[pygame.K_UP] and (player.rect.y>0):
self.rect.move_ip(0, -1)
if key[pygame.K_DOWN] and (player.rect.y<600-rectheight):
self.rect.move_ip(0, 1)
def draw(self, DISPLAYSURF):
pygame.draw.rect(DISPLAYSURF, BLUE, self.rect)
def postext(self):
pygame.image.load(self.rect).convert_alpha()
pygame.init()
player =Player()
pygame.display.set_caption('Hello World!')
clock=pygame.time.Clock()
fontObj = pygame.font.Font(None,32)
textSurfaceObj = fontObj.render('Hello World!', True, GREEN, BLUE)
#textPosition =
dt=0.1
v = pygame.math.Vector2(5,5)
ballposx=200
ballposy=200
ballrad=10
#DISPLAYSURF.fill(WHITE)
#x=10
#y=10
#dx=5
#rectpos = pygame.Rect(x,y,50,50)
#rect = pygame.draw.rect(DISPLAYSURF, BLUE, rectpos)
pygame.display.update()
running = True
n=0
while running:
for event in pygame.event.get():
if event.type == KEYDOWN:
if event.key == K_ESCAPE:
running = False
if event.type==QUIT:
pygame.quit()
sys.exit
player.handle_keys()
ballposx=ballposx+v[0]*dt
ballposy=ballposy+v[1]*dt
DISPLAYSURF.fill(WHITE)
DISPLAYSURF.blit(textSurfaceObj,(0,0))
player.draw(DISPLAYSURF)
ball=pygame.draw.circle(DISPLAYSURF, GREEN, (int(ballposx),int(ballposy)), ballrad)
rectposx1=player.rect.x
rectposy1=player.rect.y
rectvelx=-(rectposx-rectposx1)/dt
rectvely=-(rectposy-rectposy1)/dt
if ballposx-ballrad<0:
v[0]=-v[0]
if ballposy-ballrad<0:
v[1]=-v[1]
if ballposx+ballrad>600:
v[0]=-v[0]
if ballposy+ballrad>600:
v[1]=-v[1]
if player.rect.colliderect(ball):
pygame.math.Vector2.reflect_ip(v,-v+5*pygame.math.Vector2(rectvelx,rectvely))
#print (player.rect.x, rectposy, ball.x, ball.y)
ballmass=1
rectmass=5
rectposx=rectposx1
rectposy=rectposy1
print (v)
#raise SystemExit("You win!")
pygame.display.update()
clock.tick(120)
最佳答案
有两种策略可以使它无效。
移动球的方式,一旦检测到碰撞,球就会接触到球员但不会与球员相交。例如:
dx = ballposx - player.rect.centerx dy = ballposy - player.rect.centery if abs(dx) > abs(dy): ballposx = player.rect.left-ballrad if dx < 0 else player.rect.right+ballrad else: ballposy = player.rect.top-ballrad if dy < 0 else player.rect.bottom+ballrad
仅当球的运动矢量指向“反对”球的方向时才反射(reflect)球的运动。例如:
if abs(dx) > abs(dy): if (dx < 0 and v[0] > 0) or (dx > 0 and v[0] < 0): v.reflect_ip(pygame.math.Vector2(1, 0)) else: if (dy < 0 and v[1] > 0) or (dy > 0 and v[1] < 0): v.reflect_ip(pygame.math.Vector2(0, 1))
另见 Sometimes the ball doesn't bounce off the paddle in pong game
将这 2 个修复应用到您的代码中,球将正确反射(reflect)在玩家身上。例如:
ball = pygame.Rect((0,0), (ballrad*2, ballrad*2))
ball.center = int(ballposx),int(ballposy)
if player.rect.colliderect(ball):
dx = ballposx - player.rect.centerx
dy = ballposy - player.rect.centery
if abs(dx) > abs(dy):
ballposx = player.rect.left-ballrad if dx < 0 else player.rect.right+ballrad
if (dx < 0 and v[0] > 0) or (dx > 0 and v[0] < 0):
v.reflect_ip(pygame.math.Vector2(1, 0))
else:
ballposy = player.rect.top-ballrad if dy < 0 else player.rect.bottom+ballrad
if (dy < 0 and v[1] > 0) or (dy > 0 and v[1] < 0):
v.reflect_ip(pygame.math.Vector2(0, 1))
如果你想避免玩家将球推出窗外,你需要将球限制在窗口区域并像台球一样将球从窗口边缘反射出去:
min_x, min_y, max_x, max_y = 0, 0, window.get_width(), window.get_height()
ballposx = ballposx + v[0]*dt
ballposy = ballposy + v[1]*dt
if ballposx-ballrad < min_x:
ballposx = ballrad+min_x
v[0]=-v[0]
if ballposy-ballrad < min_y:
ballposy = ballrad+min_y
v[1]=-v[1]
if ballposx + ballrad > max_x:
ballposx = max_x-ballrad
v[0]=-v[0]
if ballposy + ballrad > max_y:
ballposy = max_y-ballrad
v[1]=-v[1]
另见 Use vector2 in pygame. Collide with the window frame and restrict the ball to the rectangular area分别How to make ball bounce off wall with Pygame? .
当检测到碰撞时,球员的位置必须受到限制,以便球可以发生在寡妇边界和球员之间:
if abs(dx) > abs(dy):
if dx < 0:
ballposx = max(player.rect.left-ballrad, ballrad+min_x)
player.rect.left = int(ballposx)+ballrad
else:
ballposx = min(player.rect.right+ballrad, max_x-ballrad)
player.rect.right = int(ballposx)-ballrad
有了这些变化,球甚至可以被“挤压”在窗口边缘和球员之间:
最小的例子:
import pygame
class Player(object):
def __init__(self, x, y, w, h):
self.rect = pygame.rect.Rect(x, y, w, h)
def handle_keys(self):
key = pygame.key.get_pressed()
if key[pygame.K_LEFT]:
self.rect.left = max(20, self.rect.left - 1)
if key[pygame.K_RIGHT]:
self.rect.right = min(window.get_height() - 20, self.rect.right + 1)
if key[pygame.K_UP]:
self.rect.top = max(20, self.rect.top - 1)
if key[pygame.K_DOWN]:
self.rect.bottom = min(window.get_width() - 20, self.rect.bottom + 1)
def draw(self, surface):
pygame.draw.rect(surface, (0, 0, 128), self.rect)
pygame.init()
window = pygame.display.set_mode((240, 240))
clock=pygame.time.Clock()
player = Player(20, 20, 50, 50)
v, vel = pygame.math.Vector2(1, 1), 0.5
ballPosX, ballPosY, ballRadius = 120, 120, 10
run = True
while run:
clock.tick(120)
for event in pygame.event.get():
if event.type==pygame.QUIT:
run = False
player.handle_keys()
min_x, min_y, max_x, max_y = 20, 20, window.get_width()-20, window.get_height()-20
ballPosX += v[0] * vel
ballPosY += v[1] * vel
if ballPosX - ballRadius < min_x:
ballPosX = ballRadius + min_x
v[0] = -v[0]
if ballPosY - ballRadius < min_y:
ballPosY = ballRadius + min_y
v[1] = -v[1]
if ballPosX + ballRadius > max_x:
ballPosX = max_x - ballRadius
v[0] = -v[0]
if ballPosY + ballRadius > max_y:
ballPosY = max_y - ballRadius
v[1] = -v[1]
ball = pygame.Rect((0,0), (ballRadius*2, ballRadius*2))
ball.center = int(ballPosX),int(ballPosY)
if player.rect.colliderect(ball):
dx = ballPosX - player.rect.centerx
dy = ballPosY - player.rect.centery
if abs(dx) > abs(dy):
if dx < 0:
ballPosX = max(player.rect.left-ballRadius, ballRadius+min_x)
player.rect.left = int(ballPosX)+ballRadius
else:
ballPosX = min(player.rect.right+ballRadius, max_x-ballRadius)
player.rect.right = int(ballPosX)-ballRadius
if (dx < 0 and v[0] > 0) or (dx > 0 and v[0] < 0):
v.reflect_ip(pygame.math.Vector2(1, 0))
else:
if dy < 0:
ballPosY = max(player.rect.top-ballRadius, ballRadius+min_y)
player.rect.top = int(ballPosY)+ballRadius
else:
ballPosY = min(player.rect.bottom+ballRadius, max_y-ballRadius)
player.rect.bottom = int(ballPosY)-ballRadius
ballPosY = player.rect.top-ballRadius if dy < 0 else player.rect.bottom+ballRadius
if (dy < 0 and v[1] > 0) or (dy > 0 and v[1] < 0):
v.reflect_ip(pygame.math.Vector2(0, 1))
window.fill((255, 255, 255))
pygame.draw.rect(window, (255,0,0), (18, 18, 203, 203), 2)
player.draw(window)
pygame.draw.circle(window, (0, 255, 0), (round(ballPosX), round(ballPosY)), ballRadius)
pygame.display.update()
pygame.quit()
exit()
关于python - 如何避免 PyGame 中圆形和矩形之间的小故障碰撞?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/58139771/