def __init__(self):
super(Liquid, self).__init__()
self.per_particle_mass = self.total_mass / self.num_particles
ground = self.world.CreateStaticBody(shapes=[
b2PolygonShape(box=[5.0, 0.5]),
b2PolygonShape(box=[1.0, 0.2, (0, 4), -0.2]),
b2PolygonShape(box=[1.5, 0.2, (-1.2, 5.2), -1.5]),
b2PolygonShape(box=[0.5, 50.0, (5, 0), 0.0]),
b2PolygonShape(box=[0.5, 3.0, (-8, 0), 0.0]),
b2PolygonShape(box=[2.0, 0.1, (-6, -2.8), 0.1]),
b2CircleShape(radius=0.5, pos=(-.5, -4)),
])
cx = 0
cy = 25
box_width = 2.0
box_height = 20.0
self.liquid = []
for i in range(self.num_particles):
self.createDroplet(
(b2Random(cx - box_width * 0.5, cx + box_width * 0.5),
b2Random(cy - box_height * 0.5, cy + box_height * 0.5)))
self.createBoxSurfer()
if hasattr(self, 'settings'):
self.settings.enableSubStepping = False
def __init__(self):
super(Liquid, self).__init__()
self.per_particle_mass = self.total_mass / self.num_particles
ground = self.world.CreateStaticBody(
shapes=[
b2PolygonShape(box=[5.0, 0.5]),
b2PolygonShape(box=[1.0, 0.2, (0, 4), -0.2]),
b2PolygonShape(box=[1.5, 0.2, (-1.2, 5.2), -1.5]),
b2PolygonShape(box=[0.5, 50.0, (5, 0), 0.0]),
b2PolygonShape(box=[0.5, 3.0, (-8, 0), 0.0]),
b2PolygonShape(box=[2.0, 0.1, (-6, -2.8), 0.1]),
b2CircleShape(radius=0.5, pos=(-.5, -4)),
]
)
cx = 0
cy = 25
box_width = 2.0
box_height = 20.0
self.liquid = []
for i in range(self.num_particles):
self.createDroplet((b2Random(cx - box_width * 0.5,
cx + box_width * 0.5),
b2Random(cy - box_height * 0.5,
cy + box_height * 0.5)))
self.createBoxSurfer()
if hasattr(self, 'settings'):
self.settings.enableSubStepping = False
def step_cloth(world, cloth, wind, body_size, segment_count, distance_joints,
wind_dir=(1, 1), wind_rand=0.0, distance_factor=1.45):
segment_w, segment_h = segment_count
body_spacing_w = body_size * 2
if wind:
for x in range(segment_w):
w = (b2Random(wind_dir[0] - wind_rand / 2.0,
wind_dir[0] + wind_rand / 2.0),
b2Random(wind_dir[1] - wind_rand / 2.0,
wind_dir[1] + wind_rand / 2.0))
cloth[x][-1].linearVelocity += w
# If any two points are too far from one another, find the joint connecting
# them and destroy it.
check_segments = []
for y in range(segment_h):
for x in range(segment_w):
if y > 0:
check_segments.append((cloth[x][y], cloth[x][y - 1]))
if x <= segment_w - 2:
check_segments.append((cloth[x][y], cloth[x + 1][y]))
thresh = body_spacing_w * distance_factor
for c1, c2 in check_segments:
if (c1.worldCenter - c2.worldCenter).length <= thresh:
continue
for joint in distance_joints:
if ((joint.bodyA == c1 and joint.bodyB == c2) or
(joint.bodyA == c2 and joint.bodyB == c1)):
world.DestroyJoint(joint)
distance_joints.remove(joint)
break
def step_cloth(world, cloth, wind, body_size, segment_count, distance_joints,
wind_dir=(1, 1), wind_rand=0.0, distance_factor=1.45):
segment_w, segment_h = segment_count
body_spacing_w = body_size * 2
if wind:
for x in range(segment_w):
w = (b2Random(wind_dir[0] - wind_rand / 2.0,
wind_dir[0] + wind_rand / 2.0),
b2Random(wind_dir[1] - wind_rand / 2.0,
wind_dir[1] + wind_rand / 2.0))
cloth[x][-1].linearVelocity += w
# If any two points are too far from one another, find the joint connecting
# them and destroy it.
check_segments = []
for y in range(segment_h):
for x in range(segment_w):
if y > 0:
check_segments.append((cloth[x][y], cloth[x][y - 1]))
if x <= segment_w - 2:
check_segments.append((cloth[x][y], cloth[x + 1][y]))
thresh = body_spacing_w * distance_factor
for c1, c2 in check_segments:
if (c1.worldCenter - c2.worldCenter).length <= thresh:
continue
for joint in distance_joints:
if ((joint.bodyA == c1 and joint.bodyB == c2) or
(joint.bodyA == c2 and joint.bodyB == c1)):
world.DestroyJoint(joint)
distance_joints.remove(joint)
break
def create_cloth(world, segment_count, body_size, position=(0, 30),
group_index=-1, bar_height=0.5, base_hz=15,
base_damping=0.11, density=0.2):
segment_w, segment_h = segment_count
body_spacing_w = body_size * 2
total_w = body_spacing_w * segment_w
position = b2Vec2(*position)
# The static bar at the top which holds the cloth
bar = world.CreateStaticBody(position=position)
bar.CreatePolygonFixture(box=(total_w / 2.0 + body_spacing_w,
bar_height / 2.0),
groupIndex=group_index)
box_fixture = b2FixtureDef(shape=b2CircleShape(radius=body_size),
groupIndex=group_index, density=density)
weld_joints = []
distance_joints = []
cloth = [[None] * segment_h for x in range(segment_w)]
for y in range(segment_h):
pos = position - (total_w / 2.0, y * body_spacing_w)
for x in range(segment_w):
pos += (body_spacing_w, 0.0)
body = world.CreateDynamicBody(position=pos, fixtures=box_fixture)
cloth[x][y] = body
if y == 0:
joint = world.CreateWeldJoint(bodyA=body, bodyB=bar,
anchor=body.position)
weld_joints.append(joint)
connect_bodies = []
for y in range(segment_h):
for x in range(segment_w):
if x <= segment_w - 2:
left_body = cloth[x][y]
right_body = cloth[x + 1][y]
connect_bodies.append((left_body, right_body))
if y > 0:
left_body = cloth[x][y]
right_body = cloth[x][y - 1]
connect_bodies.append((left_body, right_body))
for bodyA, bodyB in connect_bodies:
joint = world.CreateDistanceJoint(
bodyA=bodyA,
bodyB=bodyB,
anchorA=bodyA.position,
anchorB=bodyB.position,
frequencyHz=base_hz + b2Random(0, base_hz / 2.0),
dampingRatio=base_damping + b2Random(0.01, base_damping),
)
distance_joints.append(joint)
return cloth, weld_joints, distance_joints
def create_cloth(world, segment_count, body_size, position=(0, 30),
group_index=-1, bar_height=0.5, base_hz=15,
base_damping=0.11, density=0.2):
segment_w, segment_h = segment_count
body_spacing_w = body_size * 2
total_w = body_spacing_w * segment_w
position = b2Vec2(*position)
# The static bar at the top which holds the cloth
bar = world.CreateStaticBody(position=position)
bar.CreatePolygonFixture(box=(total_w / 2.0 + body_spacing_w,
bar_height / 2.0),
groupIndex=group_index)
box_fixture = b2FixtureDef(shape=b2CircleShape(radius=body_size),
groupIndex=group_index, density=density)
weld_joints = []
distance_joints = []
cloth = [[None] * segment_h for x in range(segment_w)]
for y in range(segment_h):
pos = position - (total_w / 2.0, y * body_spacing_w)
for x in range(segment_w):
pos += (body_spacing_w, 0.0)
body = world.CreateDynamicBody(position=pos, fixtures=box_fixture)
cloth[x][y] = body
if y == 0:
joint = world.CreateWeldJoint(bodyA=body, bodyB=bar,
anchor=body.position)
weld_joints.append(joint)
connect_bodies = []
for y in range(segment_h):
for x in range(segment_w):
if x <= segment_w - 2:
left_body = cloth[x][y]
right_body = cloth[x + 1][y]
connect_bodies.append((left_body, right_body))
if y > 0:
left_body = cloth[x][y]
right_body = cloth[x][y - 1]
connect_bodies.append((left_body, right_body))
for bodyA, bodyB in connect_bodies:
joint = world.CreateDistanceJoint(
bodyA=bodyA,
bodyB=bodyB,
anchorA=bodyA.position,
anchorB=bodyB.position,
frequencyHz=base_hz + b2Random(0, base_hz / 2.0),
dampingRatio=base_damping + b2Random(0.01, base_damping),
)
distance_joints.append(joint)
return cloth, weld_joints, distance_joints
def generate(self):
lower = (-8, -8)
upper = (8, 8)
self.verts = verts = []
for i in range(b2_maxPolygonVertices):
x = 10.0 * b2Random(0.0, 10.0)
y = 10.0 * b2Random(0.0, 10.0)
# Clamp onto a square to help create collinearities.
# This will stress the convex hull algorithm.
verts.append(b2Clamp((x, y), lower, upper))
def generate(self):
lower = (-8, -8)
upper = (8, 8)
self.verts = verts = []
for i in range(b2_maxPolygonVertices):
x = 10.0 * b2Random(0.0, 10.0)
y = 10.0 * b2Random(0.0, 10.0)
# Clamp onto a square to help create collinearities.
# This will stress the convex hull algorithm.
verts.append(b2Clamp((x, y), lower, upper))
def checkBounds(self):
self.hash = None
to_remove = [
drop for drop in self.liquid if drop.position.y < self.fluid_miny]
for drop in to_remove:
self.liquid.remove(drop)
self.world.DestroyBody(drop)
self.createDroplet(
(0.0 + b2Random(-0.6, 0.6), 15.0 + b2Random(-2.3, 2.0)))
if self.surfer.position.y < -15:
self.world.DestroyBody(self.surfer)
self.createBoxSurfer()
def LaunchRandomBomb(self):
"""
Create a new bomb and launch it at the testbed.
"""
p = b2Vec2(b2Random(-15.0, 15.0), 30.0)
v = -5.0 * p
self.LaunchBomb(p, v)
def checkBounds(self):
self.hash = None
to_remove = [
drop for drop in self.liquid if drop.position.y < self.fluid_miny
]
for drop in to_remove:
self.liquid.remove(drop)
self.world.DestroyBody(drop)
self.createDroplet(
(0.0 + b2Random(-0.6, 0.6), 15.0 + b2Random(-2.3, 2.0)))
if self.surfer.position.y < -15:
self.world.DestroyBody(self.surfer)
self.createBoxSurfer()
def LaunchRandomBomb(self):
"""
Create a new bomb and launch it at the testbed.
"""
p = b2Vec2(b2Random(-15.0, 15.0), 30.0)
v = -5.0 * p
self.LaunchBomb(p, v)
def Launch(self):
self.body.transform = [(0, 4), 0]
self.body.linearVelocity = (0, 0)
self.body.angularVelocity = 0
self.x = b2Random()
self.bullet.transform = [(self.x, 10), 0]
self.bullet.linearVelocity = (0, -50)
self.bullet.angularVelocity = 0
def Launch(self):
self.body.transform = [(0, 4), 0]
self.body.linearVelocity = (0, 0)
self.body.angularVelocity = 0
self.x = b2Random()
self.bullet.transform = [(self.x, 10), 0]
self.bullet.linearVelocity = (0, -50)
self.bullet.angularVelocity = 0
def __init__(self):
super(CollisionProcessing, self).__init__()
# Tell the framework we're going to use contacts, so keep track of them
# every Step.
self.using_contacts = True
# Ground body
world = self.world
ground = world.CreateBody(
shapes=b2EdgeShape(vertices=[(-50, 0), (50, 0)],)
)
xlow, xhi = -5, 5
ylow, yhi = 2, 35
random_vector = lambda: b2Vec2(
b2Random(xlow, xhi), b2Random(ylow, yhi))
# Small triangle
triangle = b2FixtureDef(
shape=b2PolygonShape(vertices=[(-1, 0), (1, 0), (0, 2)]),
density=1,
)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=triangle,
)
# Large triangle (recycle definitions)
triangle.shape.vertices = [
2.0 * b2Vec2(v) for v in triangle.shape.vertices]
tri_body = world.CreateBody(type=b2_dynamicBody,
position=random_vector(),
fixtures=triangle,
fixedRotation=True, # <--
)
# note that the large triangle will not rotate
# Small box
box = b2FixtureDef(
shape=b2PolygonShape(box=(1, 0.5)),
density=1,
restitution=0.1,
)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=box,
)
# Large box
box.shape.box = (2, 1)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=box,
)
# Small circle
circle = b2FixtureDef(
shape=b2CircleShape(radius=1),
density=1,
)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=circle,
)
# Large circle
circle.shape.radius *= 2
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=circle,
)
def createBoxSurfer(self):
self.surfer = self.world.CreateDynamicBody(position=(0, 25))
self.surfer.CreatePolygonFixture(
density=1,
box=(b2Random(0.3, 0.7), b2Random(0.3, 0.7)),
)
def createBoxSurfer(self):
self.surfer = self.world.CreateDynamicBody(position=(0, 25))
self.surfer.CreatePolygonFixture(
density=1,
box=(b2Random(0.3, 0.7), b2Random(0.3, 0.7)),
)
def __init__(self):
super(CollisionProcessing, self).__init__()
# Tell the framework we're going to use contacts, so keep track of them
# every Step.
self.using_contacts = True
# Ground body
world = self.world
ground = world.CreateBody(shapes=b2EdgeShape(vertices=[(-50,
0), (50,
0)], ))
xlow, xhi = -5, 5
ylow, yhi = 2, 35
random_vector = lambda: b2Vec2(b2Random(xlow, xhi), b2Random(
ylow, yhi))
# Small triangle
triangle = b2FixtureDef(
shape=b2PolygonShape(vertices=[(-1, 0), (1, 0), (0, 2)]),
density=1,
)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=triangle,
)
# Large triangle (recycle definitions)
triangle.shape.vertices = [
2.0 * b2Vec2(v) for v in triangle.shape.vertices
]
tri_body = world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=triangle,
fixedRotation=True, # <--
)
# note that the large triangle will not rotate
# Small box
box = b2FixtureDef(
shape=b2PolygonShape(box=(1, 0.5)),
density=1,
restitution=0.1,
)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=box,
)
# Large box
box.shape.box = (2, 1)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=box,
)
# Small circle
circle = b2FixtureDef(
shape=b2CircleShape(radius=1),
density=1,
)
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=circle,
)
# Large circle
circle.shape.radius *= 2
world.CreateBody(
type=b2_dynamicBody,
position=random_vector(),
fixtures=circle,
)
