def randomSystem(n, connect="stick"):
global euler, collisions, screen
w, h = screen.get_size()
size = min(w, h)
positions = N.random.random(3 * n) * size / 2.0 + size / 3.0
positions[2::3] = 0.0
velocities = N.random.random(3 * n) * 10.0 - 5.0
velocities[2::3] = 0.0
masses = N.random.random(n) * 10.0 + 5.0
psystem = ParticleSystem(positions, velocities, masses)
psystem.collisions = collisions
psystem.euler = euler
psystem.makePin(0)
psystem.makePin(n - 1)
for i in range(0, psystem.n - 3, 3):
psystem.makeTriangle(i, i + 1, i + 2)
if connect == "spring":
psystem.computeForces.append(("spring", i + 2, i + 3, 1.0, 100.0))
else:
psystem.constraints.append(
("stick", i + 2, i + 3, psystem.dist(i + 2, i + 3)))
for i in range(psystem.n):
psystem.computeForces.append(("drag", i, 0.1))
psystem.computeForces.append(("constant", 0, N.array(
(1.0, 0.0, 0.0)), 1.0))
psystem.computeForces.append(("constant", n - 1, N.array(
(1.0, 0.0, 0.0)), -1.0))
return psystem
def curtainSystem(n=12):
global euler, collisions, screen
n
w, h = screen.get_size()
xstep = w / float(n)
ystep = h / float(n)
positions = []
velocities = []
masses = []
for j in range(n):
for i in range(n):
positions.extend([i * xstep, j * ystep, 0.0])
velocities.extend([0.0, 0.0, 0.0])
masses.append(5.0)
psystem = ParticleSystem(positions, velocities, masses)
down = N.array((0.0, 1.0, 0.0))
for j in range(n):
for i in range(n):
p1 = i + j * n
psystem.makeConstant(p1, down, 32.0)
p2 = i + (j + 1) * n
p3 = (i + 1) + j * n
p4 = (i + 1) + (j + 1) * n
if j + 1 < n:
psystem.makeStick(p1, p2)
if i + 1 < n:
psystem.makeStick(p1, p3)
psystem.setVel((n / 2) * n - 1,
N.array((1000 + N.random.random() * 1000.0, 0.0, 0.0)))
for i in range(n):
psystem.makePin(i)
return psystem
def triangleSystem():
global euler, collisions, screen
w, h = screen.get_size()
tris = [
0.1, 0.4, 0.0, 0.1, 0.1, 0.0, 0.4, 0.1, 0.0, 0.6, 0.1, 0.0, 0.9, 0.1,
0.0, 0.9, 0.4, 0.0, 0.9, 0.6, 0.0, 0.9, 0.9, 0.0, 0.6, 0.9, 0.0, 0.4,
0.9, 0.0, 0.1, 0.9, 0.0, 0.1, 0.6, 0.0
]
scale = [float(w), float(h), 0.0] * int(len(tris) / 3)
positions = N.array(tris) * N.array(scale)
n = len(positions) / 3
velocities = N.random.random(3 * n) * 10.0 - 5.0
velocities[2::3] = 0.0
masses = N.array([16.0, 4.0, 4.0] * int(n / 3)) + N.random.random(n) * 4.0
N.random.shuffle(masses)
psystem = ParticleSystem(positions, velocities, masses)
psystem.collisions = collisions
psystem.euler = euler
for i in range(0, 12, 3):
psystem.constraints.append(
("triangle", i + 0, i + 1, i + 2, psystem.dist(i + 0, i + 1),
psystem.dist(i + 1, i + 2), psystem.dist(i + 2, i + 0)))
springk = 0.1
springl = 0.25
psystem.computeForces.append(
("spring", 2, 3, springk, psystem.dist(2, 3) * springl))
psystem.computeForces.append(
("spring", 5, 6, springk, psystem.dist(5, 6) * springl))
psystem.computeForces.append(
("spring", 8, 9, springk, psystem.dist(8, 9) * springl))
if True:
psystem.computeForces.append(
("spring", 11, 0, springk, psystem.dist(11, 0) * springl))
else:
psystem.constraints.append(("stick", 11, 0, psystem.dist(11, 0)))
for i in range(psystem.n):
if True:
psystem.computeForces.append(("drag", i, 0.075))
psystem.makePin(0)
return psystem
def gridSystem(n=8):
global euler, collisions, screen
w, h = screen.get_size()
xstep = w / float(n)
ystep = h / float(n)
positions = []
velocities = []
masses = []
for i in range(n):
for j in range(n):
positions.extend([i * xstep, j * ystep, 0.0])
velocities.extend([0.0, 0.0, 0.0])
masses.append(5.0 + N.random.random())
psystem = ParticleSystem(positions, velocities, masses)
for i in range(n):
for j in range(n):
p1 = i + j * n
p2 = i + (j + 1) * n
p3 = (i + 1) + j * n
p4 = (i + 1) + (j + 1) * n
if j + 1 < n:
psystem.computeForces.append(
("spring", p1, p2, 1.0, psystem.dist(p1, p2) * 1))
if i + 1 < n:
psystem.computeForces.append(
("spring", p1, p3, 1.0, psystem.dist(p1, p3) * 1))
if i + 1 < n and j + 1 < n:
psystem.computeForces.append(
("spring", p2, p3, 1.0, psystem.dist(p2, p3)))
psystem.computeForces.append(
("spring", p1, p4, 1.0, psystem.dist(p1, p4)))
#for i in range(n):
#psystem.setVel(i, N.array((8.0, 8.0, 0.0)))
#psystem.setVel(i+n, N.array((0.0, -10.0, 0.0)))
psystem.incPos(n * n - 1, N.array((30.0, 30.0, 0.0)))
return psystem
