Add very hack'ish rotating light via pymunk thing

[tabakrolletjie.git] / tabakrolletjie / lights.py

diff --git a/tabakrolletjie/lights.py b/tabakrolletjie/lights.py
index 92b66e0a8d4b91907fdec632724e00b0ffa9fba8..52031419611eff93d23f0c68e6daf221520d05c0 100644 (file)
--- a/tabakrolletjie/lights.py
+++ b/tabakrolletjie/lights.py
@@ -1,23 +1,93 @@
 """ May it be a light for you in dark places, when all other lights go out.
 """
 
+import time
+
 import pymunk
+import pymunk.pygame_util
+import pygame.draw
+
+from .constants import SCREEN_SIZE, LIGHT_CATEGORY, DEBUG
+
+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
+    step = 1
+    for y in range(0, h, step):
+        yield pymunk.Vec2d(left, y)
+    for x in range(0, w, step):
+        yield pymunk.Vec2d(x, top)
+    for y in range(top, -1, -step):
+        yield pymunk.Vec2d(right, y)
+    for x in range(right, -1, -step):
+        yield pymunk.Vec2d(x, bottom)
+
+
+def calculate_ray_polys(space, body, position):
+    start_time = time.time()
+    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)
+            else:
+                vertices = trial_poly.get_vertices() + [point]
+    if len(vertices) > 2:
+        ray_polys.append(pymunk.Poly(body, vertices))
+    end_time = time.time()
+    if DEBUG:
+        print(
+            "calculate_ray_polys: %d polys, %g seconds" %
+            (len(ray_polys), end_time - start_time))
+    return ray_polys
 
 
 class BaseLight(object):
     """ Common light functionality. """
 
+    COLOURS = {
+        "red": (255, 0, 0),
+        "green": (0, 255, 0),
+        "blue": (0, 255, 255),
+        "yellow": (255, 255, 0),
+        "white": (255, 255, 255),
+    }
+
     def __init__(self, colour, position):
         self.body = pymunk.Body(0, 0, pymunk.body.Body.STATIC)
         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.")
 
@@ -37,6 +107,29 @@ class SpotLight(BaseLight):
         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):
+        pygame.draw.circle(
+            surface, (255, 255, 0),
+            pymunk.pygame_util.to_pygame(self.position, surface), 5)
+
+    def render_light(self, surface):
+        subsurface = surface.copy()
+        light_colour = self.COLOURS[self.colour]
+        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, light_colour, pygame_poly, 0)
+            pygame.draw.aalines(
+                subsurface, light_colour, True, pygame_poly, 1)
+        subsurface.set_alpha(50)
+        surface.blit(subsurface, (0, 0), None)
 
 
 class Lamp(BaseLight):