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 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
