我正在使用Pymunk生成在框架中弹跳的球的视频。要渲染框架,我运行:
import pygame
from pymunk.pygame_util import DrawOptions
screen = pygame.display.set_mode((500, 500))
draw_options = DrawOptions(screen)
# define `space` with six balls
# ...
space.debug_draw(draw_options)
给出以下输出:
我们可以看到,它从球的中心到边缘画了一条黑线;我想这是为了指示每个球的旋转。
我不想画这条线:即显式传递一个标志以防止pygame绘制它,或将这条线的颜色指定为与球的其余部分相同。
有人知道怎么做吗?
答案 0 :(得分:2)
# pylint: disable=
方法实际上应该主要用于调试。我通常为我的物理对象创建精灵子类,并为它们提供Pymunk实体和形状作为属性。然后,我可以通过将debug_draw
方法中的self.rect
设置为身体坐标,并使用它来旋转图像来更新update
。
import math
import random
import pygame as pg
import pymunk as pm
from pymunk import Vec2d
def flipy(p):
"""Convert chipmunk physics to pygame coordinates."""
return Vec2d(p[0], -p[1]+800)
class Entity(pg.sprite.Sprite):
def __init__(self, pos, space, radius, mass=1):
super().__init__()
# The surface is a bit bigger, so that the circle fits better.
self.orig_image = pg.Surface((radius*2+2, radius*2+2), pg.SRCALPHA)
self.image = self.orig_image
# Draw a circle onto the image.
pg.draw.circle(
self.image,
pg.Color(random.randrange(256),
random.randrange(256),
random.randrange(256)),
(radius+1, radius+1), # +1 looks a bit better.
radius)
self.rect = self.image.get_rect(topleft=pos)
# Create a Pymunk body and a shape and add them to the space.
moment = pm.moment_for_circle(mass, radius, radius)
self.body = pm.Body(mass, moment)
self.shape = pm.Circle(self.body, radius)
self.shape.friction = .1
self.shape.elasticity = .99
self.body.position = pos
self.space = space
self.space.add(self.body, self.shape)
def update(self):
# Update the rect because it's used to blit the image.
self.rect.center = flipy(self.body.position)
# Use the body's angle to rotate the image.
self.image = pg.transform.rotozoom(self.orig_image, math.degrees(self.body.angle), 1)
self.rect = self.image.get_rect(center=self.rect.center)
if self.rect.left < 0 or self.rect.right > 1280 or self.rect.y > 790:
self.space.remove(self.body, self.shape)
self.kill()
class Game:
def __init__(self):
pg.init()
self.screen = pg.display.set_mode((1280, 800))
self.done = False
self.clock = pg.time.Clock()
# Pymunk stuff
self.space = pm.Space()
self.space.gravity = Vec2d(0.0, -900.0)
self.space.damping = .9
self.static_lines = [
pm.Segment(self.space.static_body, flipy((60.0, 780.0)), flipy((650.0, 780.0)), .0),
pm.Segment(self.space.static_body, flipy((650.0, 780.0)), flipy((1218.0, 660.0)), .0)
]
for lin in self.static_lines:
lin.friction = 0.2
lin.elasticity = 0.99
self.space.add(self.static_lines)
self.all_sprites = pg.sprite.Group()
def run(self):
while not self.done:
self.dt = self.clock.tick(60) / 1000
self.handle_events()
self.run_logic()
self.draw()
self.current_fps = self.clock.get_fps()
pg.quit()
def handle_events(self):
for event in pg.event.get():
if event.type == pg.QUIT:
self.done = True
elif event.type == pg.MOUSEBUTTONDOWN:
if event.button == 1: # Left mouse button.
# Spawn an entity.
radius = random.randrange(20, 50)
self.all_sprites.add(Entity(flipy(pg.mouse.get_pos()), self.space, radius))
if pg.mouse.get_pressed()[2]: # Right mouse button.
radius = random.randrange(20, 50)
self.all_sprites.add(Entity(flipy(pg.mouse.get_pos()), self.space, radius))
def run_logic(self):
self.space.step(1/60)
self.all_sprites.update()
def draw(self):
self.screen.fill(pg.Color(140, 120, 110))
self.all_sprites.draw(self.screen) # Draw the images of all sprites.
# Draw the static lines.
for line in self.static_lines:
body = line.body
p1 = flipy(body.position + line.a.rotated(body.angle))
p2 = flipy(body.position + line.b.rotated(body.angle))
pg.draw.lines(self.screen, pg.Color('lightgray'), False, (p1, p2), 5)
pg.display.flip()
if __name__ == '__main__':
Game().run()
我还试图找到一种方法来隐藏debug_draw
创建的这些方向/旋转线,并发现这些线在draw_options.shape_outline_color
中是彩色的,圆圈使用draw_options.shape_dynamic_color
默认。因此,当您设置
draw_options.shape_outline_color = draw_options.shape_dynamic_color
圆圈完全是蓝色的。但是,如果为每个形状指定特定的color
,它仍将使用蓝色作为线条。
使用draw_options.flags
属性,我只能完全关闭碰撞点或形状,而不能关闭线条:
# This is how you can turn off the collision points.
draw_options.flags ^= draw_options.DRAW_COLLISION_POINTS
# Stops drawing the constraints.
draw_options.flags ^= draw_options.DRAW_CONSTRAINTS
# Stops drawing all shapes.
draw_options.flags ^= draw_options.DRAW_SHAPES