Source code for espressomd.collision_detection

# Copyright (C) 2010-2022 The ESPResSo project
# This file is part of ESPResSo.
# ESPResSo is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# ESPResSo is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
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from .script_interface import ScriptInterfaceHelper, script_interface_register
from .interactions import BondedInteraction, BondedInteractions
from .code_features import assert_features

[docs]@script_interface_register class CollisionDetection(ScriptInterfaceHelper): """ Interface to the collision detection / dynamic binding. See :ref:`Creating bonds when particles collide` for detailed instructions. This class should not be instantiated by the user. Instead, use the :attr:`~espressomd.system.System.collision_detection` attribute of the system class to access the collision detection. Use method :meth:`~espressomd.collision_detection.CollisionDetection.set_params` to change the parameters of the collision detection. """ _so_name = "CollisionDetection::CollisionDetection" def __init__(self, **kwargs): assert_features("COLLISION_DETECTION") if "sip" in kwargs: super().__init__(**kwargs) return super().__init__() self.set_params(**kwargs) # Do not allow setting of individual attributes def __setattr__(self, *args, **kwargs): raise Exception( "Please set all parameters at once via collision_detection.set_params()")
[docs] def set_params(self, **kwargs): """ Set the parameters for the collision detection See :ref:`Creating bonds when particles collide` for detailed instructions. Parameters ---------- mode : :obj:`str`, {"off", "bind_centers", "bind_at_point_of_collision", "bind_three_particles", "glue_to_surface"} Collision detection mode distance : :obj:`float` Distance below which a pair of particles is considered in the collision detection bond_centers : :obj:`espressomd.interactions.BondedInteraction` Bond to add between the colliding particles bond_vs : :obj:`espressomd.interactions.BondedInteraction` Bond to add between virtual sites (for modes using virtual sites) part_type_vs : :obj:`int` Particle type of the virtual sites being created on collision (virtual sites based modes) part_type_to_be_glued : :obj:`int` particle type for ``"glue_to_surface"`` mode. See user guide. part_type_to_attach_vs_to : :obj:`int` particle type for ``"glue_to_surface"`` mode. See user guide. part_type_after_glueing : :obj:`int` particle type for ``"glue_to_surface"`` mode. See user guide. distance_glued_particle_to_vs : :obj:`float` Distance for ``"glue_to_surface"`` mode. See user guide. bond_three_particles : :obj:`espressomd.interactions.BondedInteraction` First angular bond for the ``"bind_three_particles"`` mode. See user guide three_particle_binding_angle_resolution : :obj:`int` Resolution for the angular bonds (mode ``"bind_three_particles"``). Resolution+1 bonds are needed to accommodate the case of 180 degrees angles """ if "mode" not in kwargs: raise ValueError( "Collision mode must be specified via the 'mode' argument") # Convert bonds to bond ids for name in ["bond_centers", "bond_vs", "bond_three_particle_binding"]: if name in kwargs: if isinstance(kwargs[name], BondedInteraction): kwargs[name] = kwargs[name]._bond_id self.call_method('instantiate', **kwargs)
[docs] def get_parameter(self, name): """Gets a single parameter from the collision detection.""" value = super().get_parameter(name) if name in ["bond_centers", "bond_vs", "bond_three_particle_binding"]: if value == -1: # Not defined value = None else: value = BondedInteractions()[value] return value
[docs] def get_params(self): """Returns the parameters of the collision detection as dict. """ params = {} mode = super().get_parameter("mode") for name in self.call_method("params_for_mode", mode=mode): params[name] = self.get_parameter(name) return params
def __reduce__(self): so_callback, so_callback_args = super().__reduce__() return (CollisionDetection._restore_object, (so_callback, so_callback_args, self.get_params())) @classmethod def _restore_object(cls, so_callback, so_callback_args, state): so = so_callback(*so_callback_args) so.set_params(**state) return so