def Advance(self, time_delta):
for obj in self.game_objects_list:
obj.Reset()
for obj in self.game_objects_list:
obj.AccumulateForces(self)
# Create a slight breeze that tries to keep everything in view.
center = Vector()
count = 0.0
for obj in self.game_objects_list:
if isinstance(obj, Node):
center += obj.position
count += 1.0
if count > 0.0:
center /= count
wind_force = center.Normalize() * -self.wind_force_mag
for obj in self.game_objects_list:
if isinstance(obj, Node):
obj.net_force += wind_force
for obj in self.game_objects_list:
obj.Advance(time_delta, self)
self.game_objects_list = [
obj for obj in self.game_objects_list if obj.alive
]
if not self.game_over:
pressed_keys = pygame.key.get_pressed()
move_rate = 30.0
if pressed_keys[pygame.K_UP]:
self.next_node.position.y += move_rate * time_delta
if pressed_keys[pygame.K_DOWN]:
self.next_node.position.y -= move_rate * time_delta
if pressed_keys[pygame.K_LEFT]:
self.next_node.position.x -= move_rate * time_delta
if pressed_keys[pygame.K_RIGHT]:
self.next_node.position.x += move_rate * time_delta
mouse_pos = pygame.mouse.get_pos()
if 0 <= mouse_pos[0] < self.screen.get_width(
) and 0 <= mouse_pos[1] < self.screen.get_height():
space_pos = self.SpaceFromScreen(mouse_pos)
self.next_node.position = space_pos
self.game_time_remaining -= time_delta
if self.game_time_remaining <= 0.0:
self.game_over = True
class Node(GameObject):
def __init__(self, position, color, mass=1.0):
super().__init__()
self.color = color
self.position = position
self.velocity = Vector()
self.mass = mass
self.net_force = Vector()
self.about_to_explode = False
self.explosion_time_remaining = 2.0
self.chain_number = 0
def Reset(self):
self.net_force = Vector()
def AccumulateForces(self, game):
'''
distance = self.position.Length()
force = self.position.Normalize() * -(self.mass * game.origin_mass / (distance * distance))
force = self._CheckForce(force)
self.net_force += force
'''
if self.velocity.Length() > 0.1:
air_resistance_force = self.velocity.Normalize(
) * -game.air_resistance
self.net_force += air_resistance_force
def Advance(self, time_delta, game):
acceleration = self.net_force / self.mass
self.velocity += acceleration * time_delta
self.position += self.velocity * time_delta
if self.about_to_explode:
self.explosion_time_remaining -= time_delta
if self.explosion_time_remaining <= 0.0:
self.alive = False
from explosion import Explosion
game.AddObject(
Explosion(self.position, self.mass / 2.0, self.color,
self.chain_number))
game.score += self.chain_number * int(self.mass)
if self.position.Length() > game.kill_radius:
self.alive = False
def Draw(self, game, placing=False):
center = game.SpaceToScreen(self.position)
radius = int(self.mass / 5.0)
pygame.draw.circle(game.screen, self.color, center, radius)
if self.about_to_explode:
color = (random.randint(0, 255), random.randint(0, 255),
random.randint(0, 255))
pygame.draw.circle(game.screen, color, center, radius, 2)
if placing:
node_list = game.FindAttachmentNodes()
for node in node_list:
posA = game.SpaceToScreen(node.position)
posB = game.SpaceToScreen(self.position)
color = (255, 255, 255)
pygame.draw.line(game.screen, color, posA, posB, 2)
def DrawSortKey(self):
return 2
