"""
import pymunk
+import pymunk.pygame_util
+import pygame.draw
+
+from .constants import SCREEN_SIZE, LIGHT_CATEGORY
+
+LIGHT_FILTER = pymunk.ShapeFilter(
+ mask=pymunk.ShapeFilter.ALL_MASKS ^ LIGHT_CATEGORY,
+ categories=LIGHT_CATEGORY)
+
+
+def screen_rays(pos):
+ """ An iterable that returns ordered rays from pos to the edge of the
+ screen, starting with the edge point (0, 0) and continuing clockwise
+ in pymunk coordinates.
+ """
+ w, h = SCREEN_SIZE
+ left, right, bottom, top = 0, w, 0, h
+ for y in range(h):
+ yield pymunk.Vec2d(left, y)
+ for x in range(w):
+ yield pymunk.Vec2d(x, top)
+ for y in range(top, -1, -1):
+ yield pymunk.Vec2d(right, y)
+ for x in range(right, -1, -1):
+ yield pymunk.Vec2d(x, bottom)
+
+
+def calculate_ray_polys(space, body, position):
+ position = pymunk.Vec2d(position)
+ vertices = [position]
+ ray_polys = []
+ for ray in screen_rays(position):
+ info = space.segment_query_first(position, ray, 1, LIGHT_FILTER)
+ point = ray if info is None else info.point
+ vertices.append(point)
+ if len(vertices) > 3:
+ trial_poly = pymunk.Poly(None, vertices)
+ trial_poly.update(pymunk.Transform.identity())
+ query_prev = trial_poly.point_query(vertices[-2])
+ query_pos = trial_poly.point_query(position)
+ if query_prev.distance < -0.01 or query_pos.distance < -0.01:
+ new_poly = pymunk.Poly(body, vertices[:-1])
+ vertices = [position, vertices[-1]]
+ ray_polys.append(new_poly)
+ if len(vertices) > 2:
+ ray_polys.append(pymunk.Poly(body, vertices))
+ print "NUM POLYS: ", len(ray_polys)
+ return ray_polys
class BaseLight(object):
self.colour = colour
self.position = position
- def add_to_space(self, space):
- space.remove(self.body, **self.body.shapes())
- shapes = self.determine_ray_polys(space)
- space.add(self.body, **shapes)
+ def add(self, space):
+ if self.body.space is not None:
+ space.remove(self.body, *self.body.shapes)
+ shapes = self.shapes_for_ray_polys(
+ calculate_ray_polys(space, self.body, self.position))
+ for shape in shapes:
+ shape.filter = LIGHT_FILTER
+ space.add(self.body, *shapes)
- def determine_ray_polys(self, space):
+ def shapes_for_ray_polys(self, space):
raise NotImplementedError(
"Lights should implement .determine_ray_polys.")
super(SpotLight, self).__init__(colour, position)
self.direction = direction
self.spread = spread
+ self.i = 0
+
+ def shapes_for_ray_polys(self, ray_polys):
+ return ray_polys
+
+ def render(self, surface):
+ subsurface = surface.copy()
+ pygame.draw.circle(
+ surface, (255, 255, 0),
+ pymunk.pygame_util.to_pygame(self.position, surface), 5)
+ for shape in self.body.shapes:
+ pygame_poly = [
+ pymunk.pygame_util.to_pygame(v, surface) for v in
+ shape.get_vertices()]
+ pygame.draw.polygon(
+ subsurface, (200, 200, 200), pygame_poly, 0)
+ pygame.draw.aalines(
+ subsurface, (200, 200, 200), True, pygame_poly, 1)
+ subsurface.set_alpha(200)
+ surface.blit(subsurface, (0, 0), None)
class Lamp(BaseLight):