Permalink
# Conflicts: # TODO.txt # docs/src/news.rst # docs/src/showcase.rst # examples/arrows.py # examples/balls_and_lines.py # examples/constraints.py # examples/copy_and_pickle.py # examples/damped_rotary_spring_pointer.py # examples/deformable.py # examples/flipper.py # examples/index_video.py # examples/newtons_cradle.py # examples/playground.py # examples/pygame_util_demo.py # examples/spiderweb.py # examples/tank.py # pymunk/__init__.py # pymunk/_pickle.py # pymunk/body.py # pymunk/collision_handler.py # pymunk/constraint.py # pymunk/contact_point_set.py # pymunk/space.py # pymunk/tests/__main__.py # pymunk/tests/doctests.py # pymunk/tests/test_space.py # pymunk/vec2d.py
| """A screensaver version of Newton's Cradle with an interactive mode. | |
| """ | |
| __docformat__ = "reStructuredText" | |
| import os | |
| import random | |
| import sys | |
| description = """ | |
| ---- Newton's Cradle ---- | |
| A screensaver version of Newton's Cradle with an interactive mode | |
| /s - Run in fullscreen screensaver mode | |
| /p #### - Display a preview of the screensaver using a window handler | |
| /i - Interactive mode | |
| """ | |
| if len(sys.argv) < 2: | |
| print(description) | |
| sys.exit() | |
| is_interactive = False | |
| display_flags = 0 | |
| if sys.argv[1] == "/p": # preview mode | |
| os.environ["SDL_VIDEODRIVER"] = "windib" | |
| os.environ["SDL_WINDOWID"] = sys.argv[2] | |
| display_size = (100, 100) | |
| is_interactive = False | |
| ### We must set OS env before the pygame imports.. | |
| import pygame | |
| if sys.argv[1] == "/s": # fullscreen screensaver mode | |
| display_size = (0, 0) | |
| is_interactive = False | |
| display_flags = ( | |
| display_flags | pygame.FULLSCREEN | |
| ) # FULLSCREEN) # | DOUBLEBUF | HWSURFACE ) | |
| elif sys.argv[1] == "/i": # interactive | |
| display_size = (600, 600) | |
| is_interactive = True | |
| import pymunk as pm | |
| from pymunk import Vec2d | |
| def drawcircle(image, colour, origin, radius, width=0): | |
| if width == 0: | |
| pygame.draw.circle(image, colour, origin, int(radius)) | |
| else: | |
| if radius > 65534 / 5: | |
| radius = 65534 / 5 | |
| circle = pygame.Surface( | |
| [radius * 2 + width, radius * 2 + width] | |
| ).convert_alpha() | |
| circle.fill([0, 0, 0, 0]) | |
| pygame.draw.circle( | |
| circle, | |
| colour, | |
| [circle.get_width() / 2, circle.get_height() / 2], | |
| radius + (width / 2), | |
| ) | |
| if int(radius - (width / 2)) > 0: | |
| pygame.draw.circle( | |
| circle, | |
| [0, 0, 0, 0], | |
| [circle.get_width() / 2, circle.get_height() / 2], | |
| abs(int(radius - (width / 2))), | |
| ) | |
| image.blit( | |
| circle, | |
| [ | |
| origin[0] - (circle.get_width() / 2), | |
| origin[1] - (circle.get_height() / 2), | |
| ], | |
| ) | |
| def reset_bodies(space): | |
| for body in space.bodies: | |
| body.position = Vec2d(*body.start_position) | |
| body.force = 0, 0 | |
| body.torque = 0 | |
| body.velocity = 0, 0 | |
| body.angular_velocity = 0 | |
| color = pygame.Color( | |
| random.randint(1, 255), random.randint(1, 255), random.randint(1, 255) | |
| ) | |
| for shape in space.shapes: | |
| shape.color = color | |
| def main(): | |
| pygame.init() | |
| screen = pygame.display.set_mode(display_size, display_flags) | |
| width, height = screen.get_size() | |
| def to_pygame(p): | |
| """Small hack to convert pymunk to pygame coordinates""" | |
| return int(p.x), int(-p.y + height) | |
| def from_pygame(p): | |
| return to_pygame(p) | |
| clock = pygame.time.Clock() | |
| running = True | |
| font = pygame.font.Font(None, 16) | |
| ### Physics stuff | |
| space = pm.Space() | |
| space.gravity = (0.0, -1900.0) | |
| space.damping = 0.999 # to prevent it from blowing up. | |
| mouse_body = pm.Body(body_type=pm.Body.KINEMATIC) | |
| bodies = [] | |
| for x in range(-100, 150, 50): | |
| x += width / 2 | |
| offset_y = height / 2 | |
| mass = 10 | |
| radius = 25 | |
| moment = pm.moment_for_circle(mass, 0, radius, (0, 0)) | |
| body = pm.Body(mass, moment) | |
| body.position = (x, -125 + offset_y) | |
| body.start_position = Vec2d(*body.position) | |
| shape = pm.Circle(body, radius) | |
| shape.elasticity = 0.9999999 | |
| space.add(body, shape) | |
| bodies.append(body) | |
| pj = pm.PinJoint(space.static_body, body, (x, 125 + offset_y), (0, 0)) | |
| space.add(pj) | |
| reset_bodies(space) | |
| selected = None | |
| if not is_interactive: | |
| pygame.time.set_timer(pygame.USEREVENT + 1, 70000) # apply force | |
| pygame.time.set_timer(pygame.USEREVENT + 2, 120000) # reset | |
| pygame.event.post(pygame.event.Event(pygame.USEREVENT + 1)) | |
| pygame.mouse.set_visible(False) | |
| while running: | |
| for event in pygame.event.get(): | |
| if event.type == pygame.QUIT: | |
| running = False | |
| elif event.type == pygame.KEYDOWN and event.key == pygame.K_p: | |
| pygame.image.save(screen, "newtons_cradle.png") | |
| if event.type == pygame.USEREVENT + 1: | |
| r = random.randint(1, 4) | |
| for body in bodies[0:r]: | |
| body.apply_impulse_at_local_point((-6000, 0)) | |
| if event.type == pygame.USEREVENT + 2: | |
| reset_bodies(space) | |
| elif ( | |
| event.type == pygame.KEYDOWN | |
| and event.key == pygame.K_r | |
| and is_interactive | |
| ): | |
| reset_bodies(space) | |
| elif ( | |
| event.type == pygame.KEYDOWN | |
| and event.key == pygame.K_f | |
| and is_interactive | |
| ): | |
| r = random.randint(1, 4) | |
| for body in bodies[0:r]: | |
| body.apply_impulse_at_local_point((-6000, 0)) | |
| elif event.type == pygame.MOUSEBUTTONDOWN and is_interactive: | |
| if selected != None: | |
| space.remove(selected) | |
| p = from_pygame(Vec2d(*event.pos)) | |
| hit = space.point_query_nearest(p, 0, pm.ShapeFilter()) | |
| if hit != None: | |
| shape = hit.shape | |
| rest_length = mouse_body.position.get_distance(shape.body.position) | |
| ds = pm.DampedSpring( | |
| mouse_body, shape.body, (0, 0), (0, 0), rest_length, 1000, 10 | |
| ) | |
| space.add(ds) | |
| selected = ds | |
| elif event.type == pygame.MOUSEBUTTONUP and is_interactive: | |
| if selected != None: | |
| space.remove(selected) | |
| selected = None | |
| elif event.type == pygame.KEYDOWN: | |
| running = False | |
| elif event.type == pygame.MOUSEBUTTONDOWN: | |
| running = False | |
| mpos = pygame.mouse.get_pos() | |
| p = from_pygame(Vec2d(*mpos)) | |
| mouse_body.position = p | |
| ### Clear screen | |
| screen.fill(pygame.Color("black")) | |
| ### Draw stuff | |
| for c in space.constraints: | |
| pv1 = c.a.position + c.anchor_a | |
| pv2 = c.b.position + c.anchor_b | |
| p1 = to_pygame(pv1) | |
| p2 = to_pygame(pv2) | |
| pygame.draw.aalines(screen, pygame.Color("lightgray"), False, [p1, p2]) | |
| for ball in space.shapes: | |
| p = to_pygame(ball.body.position) | |
| drawcircle(screen, ball.color, p, int(ball.radius), 0) | |
| # pygame.draw.circle(screen, ball.color, p, int(ball.radius), 0) | |
| ### Update physics | |
| fps = 50 | |
| iterations = 25 | |
| dt = 1.0 / float(fps) / float(iterations) | |
| for x in range(iterations): # 10 iterations to get a more stable simulation | |
| space.step(dt) | |
| ### Flip screen | |
| if is_interactive: | |
| screen.blit( | |
| font.render( | |
| "fps: " + str(clock.get_fps()), True, pygame.Color("white") | |
| ), | |
| (0, 0), | |
| ) | |
| screen.blit( | |
| font.render( | |
| "Press left mouse button and drag to interact", | |
| True, | |
| pygame.Color("darkgrey"), | |
| ), | |
| (5, height - 35), | |
| ) | |
| screen.blit( | |
| font.render( | |
| "Press R to reset, any other key to quit", | |
| True, | |
| pygame.Color("darkgrey"), | |
| ), | |
| (5, height - 20), | |
| ) | |
| pygame.display.flip() | |
| clock.tick(fps) | |
| if __name__ == "__main__": | |
| sys.exit(main()) |