SPHEntity（光滑粒子流体动力学实体）#

class genesis.engine.entities.sph_entity.SPHEntity(scene, solver, material, morph, surface, particle_size, idx, particle_start, name: str | None = None)[source]#

Bases: ParticleEntity

SPH-based particle entity.

Parameters:

  • scene (Scene) – The simulation scene.

  • solver (Solver) – The solver handling the simulation logic.

  • material (Material) – Material properties (e.g., density, stiffness).

  • morph (Morph) – Morphological configuration.

  • surface (Surface) – Surface constraints or geometry.

  • particle_size (float) – The size of each particle.

  • idx (int) – Index of this entity in the scene.

  • particle_start (int) – Start index for the particles belonging to this entity.

init_sampler()[source]#

Initialize the particle sampler based on the material’s sampling method.

Raises:

GenesisException – If the sampler is not one of the supported types: ‘regular’, ‘pbs’, or ‘pbs-sdf_res’.

add_grad_from_state(state)[source]#

Apply gradients from a given state.

Parameters:

state (SPHEntityState) – The state from which to compute gradients.

get_frame(f: <gstaichi._lib.core.gstaichi_python.DataTypeCxx object at 0x10917d0f0>, pos: NdarrayType(dtype=None, ndim=None, layout=Layout.AOS, needs_grad=None), vel: NdarrayType(dtype=None, ndim=None, layout=Layout.AOS, needs_grad=None))[source]#

Retrieve particle positions and velocities for the given frame.

Parameters:

  • f (int) – Frame index.

  • pos (ndarray) – Output array for positions (n_envs, n_particles, 3).

  • vel (ndarray) – Output array for velocities (n_envs, n_particles, 3).

get_state()[source]#

Get the current state of the SPHEntity including positions, velocities, .

Returns:

state – The current particle state for the entity.

Return type:

SPHEntityState

set_particles_pos(poss, particles_idx_local=None, envs_idx=None)[source]#

Set the position of some particles.

Parameters:

  • poss (torch.Tensor, shape (M, N, 3)) – Target position of each particle.

  • particles_idx_local (torch.Tensor, shape (M, N)) – Index of the particles relative to this entity. If None, all particles will be considered. Defaults to None.

  • envs_idx (torch.Tensor, shape (M,)) – The indices of the environments to set. If None, all environments will be considered. Defaults to None.

get_particles_pos(envs_idx=None)[source]#

Retrieve current particle positions from the solver.

Parameters:

envs_idx (None | int | array_like, shape (M,), optional) – The indices of the environments to set. If None, all environments will be considered. Defaults to None.

Returns:

poss – Tensor of particle positions.

Return type:

torch.Tensor, shape (M, n_particles, 3)

get_position(envs_idx=None)[source]#
set_particles_vel(vels, particles_idx_local=None, envs_idx=None)[source]#

Set the velocity of some particles.

Parameters:

  • vels (torch.Tensor, shape (M, N, 3)) – Target velocity of each particle.

  • particles_idx_local (torch.Tensor, shape (M, N)) – Index of the particles relative to this entity. If None, all particles will be considered. Defaults to None.

  • envs_idx (torch.Tensor, shape (M,)) – The indices of the environments to set. If None, all environments will be considered. Defaults to None.

get_particles_vel(envs_idx=None)[source]#

Retrieve current particle velocities from the solver.

Parameters:

envs_idx (None | int | array_like, shape (M,), optional) – The indices of the environments to set. If None, all environments will be considered. Defaults to None.

Returns:

poss – Tensor of particle velocities, shape (M, n_particles, 3).

Return type:

torch.Tensor

set_particles_active(actives, particles_idx_local=None, envs_idx=None)[source]#

Set the velocity of some particles.

Parameters:

  • actives (torch.Tensor, shape (M, N, 3)) – Activeness boolean flags for each particle.

  • particles_idx_local (torch.Tensor, shape (M, N)) – Index of the particles relative to this entity. If None, all particles will be considered. Defaults to None.

  • envs_idx (torch.Tensor, shape (M,)) – The indices of the environments to set. If None, all environments will be considered. Defaults to None.

get_particles_active(envs_idx=None)[source]#

Retrieve current particle activeness boolean flags from the solver.

Parameters:

envs_idx (None | int | array_like, shape (M,), optional) – The indices of the environments to set. If None, all environments will be considered. Defaults to None.

Returns:

poss – Tensor of particle activeness boolean flags.

Return type:

torch.Tensor, shape (M, n_particles, 3)