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# -*- encoding=utf-8 -*-
## Omega is the super-class that orchestrates the whole program.
## It holds the entire simulation (MetaBody), takes care of loading/saving,
## starting/stopping the simulation, loads plugins and more.
o = Omega() # for advaned folks: this creates default MetaBody as well
## Engines are called consecutively at each iteration. Their order matters.
##
## Some of them work by themselves (GlobalEngine, PartialEngine - the difference of these two is unimportant).
##
## MetaEngines act as dispatchers and based on the type of objects they operate on, different EngineUnits are called.
o.engines = [
## Resets forces and momenta the act on bodies
ForceResetter(),
## associates bounding volume - in this case, AxisAlignedBoundingBox (Aabb) - to each body.
## Using bounding boxes created, find possible body collisions.
## These possible collisions are inserted in O.interactions container (Scene::interactions in c++).
InsertionSortCollider([
Bo1_Sphere_Aabb(),
Bo1_Box_Aabb(),
]),
InteractionLoop(
## Decide whether the potential collisions are real; if so, create geometry information about each potential collision.
## Here, the decision about which EngineUnit to use depends on types of _both_ bodies.
## Note that there is no EngineUnit for box-box collision. They are not implemented.
[Ig2_Sphere_Sphere_ScGeom(), Ig2_Box_Sphere_ScGeom()],
## Create physical information about the interaction.
## This may consist in deriving contact rigidity from elastic moduli of each body, for example.
## The purpose is that the contact may be "solved" without reference to related bodies,
## only with the information contained in contact geometry and physics.
[Ip2_FrictMat_FrictMat_FrictPhys()],
## "Solver" of the contact, also called (consitutive) law.
## Based on the information in interaction physics and geometry, it applies corresponding forces on bodies in interaction.
[Law2_ScGeom_FrictPhys_CundallStrack()]
),
## Apply gravity: all bodies will have gravity applied on them.
## Note the engine parameter 'gravity', a vector that gives the acceleration.
## Forces acting on bodies are damped to artificially increase energy dissipation in simulation.
## (In this model, the restitution coefficient of interaction is 1, which is not realistic.)
## This MetaEngine acts on all PhysicalActions and selects the right EngineUnit base on type of the PhysicalAction.
#
# note that following 4 engines (till the end) can be replaced by an optimized monolithic version:
NewtonIntegrator(damping=0.1, gravity=[0, 0, -9.81])
]
## The yade.utils module contains some handy functions, like yade.utils.box and yade.utils.sphere.
## After this import, they will be accessible as utils.box and utils.sphere.
### UPDATE: utils is loaded automatically, no longer need to import
#from yade import utils
## create bodies in the simulation: one box in the origin and one floating above it.
##
## The box:
## * extents: half-size of the box. [.5,.5,.5] is unit cube
## * center: position of the center of the box
## * dynamic: it is not dynamic, i.e. will not move during simulation, even if forces are applied to it
o.bodies.append(box(center=[0, 0, 0], extents=[.5, .5, .5], color=[0, 0, 1], fixed=True))
## The sphere
##
## * First two arguments are radius and center, respectively. They are used as "positional arguments" here:
## python will deduce based on where they are what they mean.
##
## It could also be written without using sphere - see gui/py/utils.py for the code of the sphere function
o.bodies.append(sphere([0, 0, 2], 1, color=[0, 1, 0]))
## Estimate timestep from p-wave speed and multiply it by safety factor of .2
o.dt = .01 * PWaveTimeStep()
## Save the scene to file, so that it can be loaded later. Supported extension are: .xml, .xml.gz, .xml.bz2.
o.save('/tmp/a.xml.bz2')
#o.run(100000); o.wait(); print o.iter/o.realtime,'iterations/sec'
def onBodySelect(id):
print("Selected:", id)
highlightNone()
for i in O.interactions.withBody(id):
O.bodies[i.id2 if i.id1 == id else i.id1].shape.highlight = True
print(i.id1, i.id2, i.phys, i.geom)
try:
from yade import qt
qt.View()
qt.Controller()
except ImportError:
pass
O.run(20000)
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