我正在研究pygame教程，目前我正在试图弄清楚如何选择一个圆球，这是一个球击中另一个球，而球又击倒了一个球。当球击中盒子时，盒子敲击工作正常。但是，当我添加鼠标移动时，我可以再次选择球并将其放置在相同的位置，以便再次击中它以便盒子再次敲击。球只是向后滚动而没有射击第二个球来敲击盒子。这是以前的代码，它可以用一个球击中另一个球而不用鼠标移动，即不允许选择和拖动球。
import pygame
from pygame.locals import *
from pygame.color import *
import pymunk as pm
from pymunk import Vec2d
import sys
from random import randint
def to_pygame(p):
"""Small hack to convert pymunk to pygame coordinates"""
return int(p[0]), int(-p[1]+600)
def draw_ball(screen, ball, colour):
r = ball.radius
rot = ball.body.rotation_vector
p = to_pygame(ball.body.position)
p2 = Vec2d(rot.x, -rot.y) * r * 0.9
pygame.draw.line(screen, THECOLORS["red"], p, p+p2)
pygame.draw.circle(screen, colour, p, int(r), 3)
def add_ball(space, x=0, y=130):
mass = 1.3
radius = 20
inertia = pm.moment_for_circle(mass, 0, radius, (0,0))
body = pm.Body(mass, inertia)
body.position = (x,y)
shape = pm.Circle(body, radius, (0,0))
shape.friction = 10.0
shape.elasticity = 1.0
space.add(body, shape)
return shape
def add_box(space, size, pos, mass=0.3):
points = [(-size, -size), (-size, size), (size,size), (size, -size)]
moment = pm.moment_for_poly(int(mass), points, (0,0))
body = pm.Body(mass, moment)
body.position = pos
shape = pm.Poly(body, points, (0,0))
shape.friction = 1
space.add(body,shape)
return shape
def draw_box(screen, box):
ps = box.get_points()
ps.append(ps[0])
newps = [to_pygame(x) for x in ps]
pygame.draw.polygon(screen, THECOLORS["blue"], newps, 3)
def main():
pygame.init()
screen = pygame.display.set_mode((600, 600))
pygame.display.set_caption("Impulsive balls")
clock = pygame.time.Clock()
balls = []
space = pm.Space()
space.gravity = (0.0, -300.0)
# ground
body = pm.Body()
shape = pm.Segment(body, (0,100), (450,100), .0)
shape.friction = 6.0
space.add(shape)
# hidden ramp
body = pm.Body()
slope = pm.Segment(body, (0,100), (180,150), .0)
space.add(slope)
balls.append(add_ball(space, 10, 130))
balls.append(add_ball(space, 100, 150))
#joint = pm.PinJoint(balls[0].body, balls[1].body)
#joint.distance = 90
mass = 1.0
size = 20
box = add_box(space, size, (400,100+size), mass)
count = 0
while 1:
space.step(1/30.0)
clock.tick(30)
for event in pygame.event.get():
if event.type == QUIT:
pygame.quit()
sys.exit(0)
elif event.type == KEYDOWN:
if event.key == K_ESCAPE:
pygame.quit()
sys.exit(0)
if count == 10:
pm.Body.apply_impulse(balls[0].body, (450,0))
screen.fill(THECOLORS["white"])
pygame.draw.line(screen, THECOLORS["red"], to_pygame((0,100)), to_pygame((450,100)), 3)
pygame.draw.line(screen, THECOLORS["red"], to_pygame((0,100)), to_pygame((180,150)), 3)
draw_box(screen, box)
for ball in balls:
draw_ball(screen, ball, THECOLORS["green"])
pygame.display.flip()
count += 1
if __name__ == '__main__':
main()
这是我添加鼠标移动代码的第二个版本
import pygame
from pygame.locals import *
from pygame.color import *
import pymunk as pm
from pymunk import Vec2d
import sys
from random import randint
def to_pygame(p):
"""Small hack to convert pymunk to pygame coordinates"""
return int(p[0]), int(-p[1]+600)
def from_pygame(p):
return to_pygame(p)
def draw_ball(screen, ball, colour):
r = ball.radius
rot = ball.body.rotation_vector
p = to_pygame(ball.body.position)
p2 = Vec2d(rot.x, -rot.y) * r * 0.9
pygame.draw.line(screen, THECOLORS["blue"], p, p+p2)
pygame.draw.circle(screen, colour, p, int(r), 3)
def add_ball(space, x=0, y=130):
mass = 1.3 #1.5
radius = 20
inertia = pm.moment_for_circle(mass, 0, radius, (0,0))
body = pm.Body(mass, inertia)
body.position = (x,y)
shape = pm.Circle(body, radius, (0,0))
shape.friction = 10.0
shape.elasticity = 1.0
space.add(body, shape)
return shape
def add_box(space, size, pos, mass=0.3):
points = [(-size, -size), (-size, size), (size,size), (size, -size)]
moment = pm.moment_for_poly(int(mass), points, (0,0))
body = pm.Body(mass, moment)
body.position = pos
shape = pm.Poly(body, points, (0,0))
shape.friction = 1
space.add(body,shape)
return shape
def draw_box(screen, box):
ps = box.get_points()
ps.append(ps[0])
newps = [to_pygame(x) for x in ps]
pygame.draw.polygon(screen, THECOLORS["blue"], newps, 3)
def main():
pygame.init()
screen = pygame.display.set_mode((600, 600))
pygame.display.set_caption("Impulsive balls")
clock = pygame.time.Clock()
body = []
selected = None
balls = []
space = pm.Space()
space.gravity = (0.0, -300.0)
# ground
body = pm.Body()
shape = pm.Segment(body, (0,100), (450,100), .0)
shape.friction = 6.0
space.add(shape)
# hidden ramp
body = pm.Body()
slope = pm.Segment(body, (0,100), (180,150), .0)
space.add(slope)
balls.append(add_ball(space, 10, 130))
balls.append(add_ball(space, 100, 150))
#joint = pm.PinJoint(balls[0].body, balls[1].body)
#joint.distance = 90
mass = 1.0
size = 20
box = add_box(space, size, (400,100+size), mass)
count = 0
while 1:
space.step(1/30.0)
clock.tick(30)
for event in pygame.event.get():
if event.type == QUIT:
pygame.quit()
sys.exit(0)
elif event.type == KEYDOWN:
if event.key == K_ESCAPE:
pygame.quit()
sys.exit(0)
if count == 10:
pm.Body.apply_impulse(balls[0].body, (450,0))
if event.key == K_p:
balls[0].body.apply_impulse((450,0))
if event.key == K_s:
balls[0].body.apply_impulse((-450,0))
elif event.type == MOUSEBUTTONDOWN:
p = from_pygame(Vec2d(event.pos))
selected = space.point_query_first(p)
elif event.type == MOUSEBUTTONUP:
if selected != None:
selected = None
elif event.type == MOUSEMOTION:
if selected != None:
selected.body.position = from_pygame(event.pos)
screen.fill(THECOLORS["white"])
pygame.draw.line(screen, THECOLORS["red"], to_pygame((0,100)), to_pygame((450,100)), 3)
pygame.draw.line(screen, THECOLORS["red"], to_pygame((0,100)), to_pygame((180,150)), 3)
draw_box(screen, box)
for ball in balls:
draw_ball(screen, ball, THECOLORS["green"])
pygame.display.flip()
count += 1
if __name__ == '__main__':
main()
另外，我怎样才能将球放在同一个位置，以便我可以拖动它并推动另一个球来敲击球而不是让球回滚，所以稍后我可以再次选择击球并放置它在没有回滚的球旁边
答案 0 :(得分：1)
对于你的第一个问题，球没有在第二个文件中射击。问题是您已将该代码放入事件块中，该事件块仅在触发外部事件时发生（例如按下某个键）。要修复它，需要将该块移出for循环，如下所示：
...
while 1:
space.step(1/30.0)
clock.tick(30)
for event in pygame.event.get():
if event.type == QUIT:
pygame.quit()
sys.exit(0)
elif event.type == KEYDOWN:
if event.key == K_ESCAPE:
pygame.quit()
sys.exit(0)
if event.key == K_p:
balls[0].body.apply_impulse((450,0))
if event.key == K_s:
balls[0].body.apply_impulse((-450,0))
elif event.type == MOUSEBUTTONDOWN:
p = from_pygame(Vec2d(event.pos))
selected = space.point_query_first(p)
elif event.type == MOUSEBUTTONUP:
if selected != None:
selected = None
elif event.type == MOUSEMOTION:
if selected != None:
selected.body.position = from_pygame(event.pos)
if count == 10:
pm.Body.apply_impulse(balls[0].body, (450,0))
...
为防止球移动，我建议将球放在平地上。我对main进行了以下更改以显示我的意思。请注意，我禁用了球的射击，以便您可以看到球保持在原位。我还建议您在屏幕上放置一些看不见的墙壁，以防止所有物体卡在框架内。
...
def main():
pygame.init()
screen = pygame.display.set_mode((600, 600))
pygame.display.set_caption("Impulsive balls")
clock = pygame.time.Clock()
body = []
selected = None
balls = []
space = pm.Space()
space.gravity = (0.0, -300.0)
# ground
body = pm.Body()
shape = pm.Segment(body, (0,100), (450,100), .0)
shape.friction = 6.0
space.add(shape)
# hidden ramp
body = pm.Body()
slope = pm.Segment(body, (20,100), (180,150), .0)
space.add(slope)
body = pm.Body()
slopetop = pm.Segment(body, (180,150), (190,150), .0)
space.add(slopetop)
balls.append(add_ball(space, 10, 130))
balls.append(add_ball(space, 185, 170))
#joint = pm.PinJoint(balls[0].body, balls[1].body)
#joint.distance = 90
mass = 1.0
size = 20
box = add_box(space, size, (400,100+size), mass)
count = 0
while 1:
space.step(1/30.0)
clock.tick(30)
for event in pygame.event.get():
if event.type == QUIT:
pygame.quit()
sys.exit(0)
elif event.type == KEYDOWN:
if event.key == K_ESCAPE:
pygame.quit()
sys.exit(0)
if event.key == K_p:
balls[0].body.apply_impulse((450,0))
if event.key == K_s:
balls[0].body.apply_impulse((-450,0))
elif event.type == MOUSEBUTTONDOWN:
p = from_pygame(Vec2d(event.pos))
selected = space.point_query_first(p)
elif event.type == MOUSEBUTTONUP:
if selected != None:
selected = None
elif event.type == MOUSEMOTION:
if selected != None:
selected.body.position = from_pygame(event.pos)
if count == 10 and 0:
pm.Body.apply_impulse(balls[0].body, (450,0))
screen.fill(THECOLORS["white"])
pygame.draw.line(screen, THECOLORS["red"], to_pygame((0,100)), to_pygame((450,100)), 3)
pygame.draw.line(screen, THECOLORS["red"], to_pygame((20,100)), to_pygame((180,150)), 3)
pygame.draw.line(screen, THECOLORS["red"], to_pygame((180,150)), to_pygame((190,150)), 3)
draw_box(screen, box)
for ball in balls:
draw_ball(screen, ball, THECOLORS["green"])
pygame.display.flip()
count += 1
...