Add code for collisions and explosions

This does the dumbest thing. Collision is on rects. The debris
explodes mostly logically (some bug in generating new particles)

asteroids.py

@@ -13,6 +13,9 @@ def spawn_bullet(ship, rng, objects):
 
 def spawn_asteroid(ship, rng, objects, *, pos=None, size=None, num=1):
 
+    if size != None and size < 0:
+        return
+
     if not pos:
 
         # Get a random position in the space (away from the ship)
@@ -23,9 +26,11 @@ def spawn_asteroid(ship, rng, objects, *, pos=None, size=None, num=1):
 
         cx += r*np.cos(theta)
         cy += r*np.sin(theta)
+        max_vel = 0.01
 
     else:
         cx,cy = pos
+        max_vel = 0.5
 
     for i in range(num):
 
@@ -36,15 +41,15 @@ def spawn_asteroid(ship, rng, objects, *, pos=None, size=None, num=1):
         theta = 2*constants.PI * rng.random()
         x = r*np.cos(theta) + cx
         y = r*np.sin(theta) + cy
-        vx = (2*rng.random() -1) * 0.01
-        vy = (2*rng.random() -1) * 0.01
+        vx = (2*rng.random() -1) * max_vel
+        vy = (2*rng.random() -1) * max_vel
         omega = (2*rng.random() -1) * 0.1
         objects.add( Debris(size=size, x=x, y=y, vx=vx, vy=vy, omega=omega))
-
 
 def main():
 
     pygame.init()
+    pygame.mixer.init()
 
     pygame.display.set_caption('BWasteroids')
     screen = pygame.display.set_mode((constants.SCREEN_WIDTH,constants.SCREEN_HEIGHT), flags=pygame.SCALED)
@@ -126,6 +131,20 @@ def main():
 
         # Simulate()
         objects.update(tick)
+
+        # Check for collisions
+        collisions = pygame.sprite.groupcollide(objects, objects, False, False)
+
+        for c1 in collisions:
+            for c2 in collisions[c1]:
+                if c1 in objects and c2 in objects:
+                    if c1 != c2:
+                        if isinstance(c1, Bullet) and isinstance(c2, Debris):
+                            objects.remove(c2)
+                            spawn_asteroid(ship, rng, objects, pos=(c2.x, c2.y), size=(c2.size-1), num=rng.integers(1,4))
+                            c2.kill()
+                            del c2
+                            objects.remove(c1)
 
         # render()
         rects = objects.draw(screen)

bullet.py

@@ -7,6 +7,8 @@ class Bullet(physics.PhysicsObject):
 
     def __init__(self, ship):
 
+        self.name = 'Bullet'
+
         d = constants.BULLET_SPAWN_RADIUS
         x = ship.x + d*np.cos(constants.DEG_TO_RAD*ship.angle)
         y = ship.y + d*np.sin(constants.DEG_TO_RAD*ship.angle)
@@ -22,6 +24,10 @@ def __init__(self, ship):
         self.rect = pygame.Rect(x,y,5,5)
         self.visible = 1
 
+        col_surface = self.image.copy()
+        pygame.draw.circle(col_surface, pygame.Color("white"), col_surface.get_rect().center, 2, 0)
+        self.mask = pygame.mask.from_surface(col_surface)
+
         self.base_color = pygame.Color("#adff2fff")
         self.life = constants.FIRE_LIFETIME
 

debris.py

@@ -11,6 +11,8 @@ def __init__(self, size, x=0.0, y=0.0, vx=0.0, vy=0.0, angle=90.0, omega=0.0):
 
         super().__init__(x=x, y=y, vx=vx, vy=vy, angle=angle)
 
+        self.name = "Debris"
+
         self.omega = omega
 
         self.size = size
@@ -20,15 +22,25 @@ def __init__(self, size, x=0.0, y=0.0, vx=0.0, vy=0.0, angle=90.0, omega=0.0):
         self.image = pygame.Surface([px,px], flags=pygame.SRCALPHA)
         self.rect = pygame.Rect(x,y,px,px)
         self.visible = 1
-
+        
         self.base_images = [ pygame.Surface([px,px], flags=pygame.SRCALPHA) for i in range(360) ]
+        self.mask = None
+        self.collision_masks = [ None for i in range(360) ]
+
         self.init_base_image(px)
 
         self.explosion_sound = pygame.mixer.Sound("sounds/explosion.wav")
         self.explosion_channel = pygame.mixer.Channel(constants.EXPLOSION_CHANNEL)
 
+    def kill(self):
+
+        if not self.explosion_channel.get_busy():
+            self.explosion_channel.play(self.explosion_sound, loops=0)
+
     def init_base_image(self, px):
 
+        # Creates the initial images and the collision masks
+
         # Pick 3 vertices of a 16-gon. Pull them into the center
         NUM_DENTS = 4
         NUM_PIECES = 15
@@ -59,15 +71,19 @@ def init_base_image(self, px):
 
                 pts.append( (x,y) )
 
-            pygame.draw.aalines(self.base_images[n], pygame.Color("#bc8f8fff"), True, pts)
-            pygame.draw.aalines(self.base_images[n], pygame.Color("#bc8f8fff"), True, pts)
+            #pygame.draw.aalines(self.base_images[n], pygame.Color("#bc8f8fff"), True, pts)
+            #pygame.draw.aalines(self.base_images[n], pygame.Color("#bc8f8fff"), True, pts)
+            pygame.draw.polygon(self.base_images[n], pygame.Color("#d2b48cff"), pts, 0)
+            self.collision_masks[n] = pygame.mask.from_surface(self.base_images[n])
 
     def update(self, tick):
 
         super().update(tick)
 
         self.angle += self.omega * tick
 
-        self.image = self.base_images[ int(np.round(self.angle)) % 360 ]
+        idx = int(np.round(self.angle)) % 360
+        self.image = self.base_images[ idx ]
+        self.mask = self.collision_masks[idx]
 
         self.dirty = 1

physics.py

@@ -9,12 +9,16 @@ def __init__(self, x=0.0, y=0.0, vx=0.0, vy=0.0, angle=0):
 
         pygame.sprite.DirtySprite.__init__(self)
 
+        self.name = 'N/A'
+
         self.x = x
         self.y = y
         self.vx = vx
         self.vy = vy
         self.angle = angle
 
+        self.mask = None
+
     def update(self, tick):
 
         self.x += self.vx * tick/1000.0

ship.py

@@ -9,6 +9,8 @@ def __init__(self, x=0.0, y=0.0, vx=0.0, vy=0.0, angle=90.0):
 
         super().__init__(x=x, y=y, vx=vx, vy=vy, angle=angle)
 
+        self.name = 'Ship'
+
         self.lives = 3
 
         self.firing = False