superdex::RigidActorParams Struct Reference

Parameters to create a rigid body actor. More...

#include <mochi_structs.h>

Inheritance diagram for superdex::RigidActorParams:

Public Member Functions
bool	operator== (RigidActorParams const &) const =default

Public Attributes
std::optional< Real3 >	angularVelocity
	Optional initial angular velocity in world frame [rad/s], zero otherwise.
ActorBoundaryElementType	boundaryElementType = ActorBoundaryElementType::Default
	Finite element type for boundary discretization.
std::optional< BoundarySubsamplingParams >	boundarySubsampling
	Optional subsampling for boundary integrals such as contact.
std::optional< Real3 >	centerOfMass
	Position [m] of the center of mass in the actor's local frame.
ColliderType	colliderType = ColliderType::Auto
	Collision detection geometry.
ContactParams	contact
	Contact mechanics parameters.
std::optional< real >	density
	Uniform density [kg/m³] of the actor.
bool	hasGravity = true
	If true, actor is affected by gravity.
bool	isStatic = false
	If true, actor will be static (fixed in space).
DynamicString	layer
	Contact layer name for filtering contacts between actors.
std::optional< Real3 >	linearVelocity
	Optional initial linear velocity of the center of mass in world frame [m/s], zero otherwise.
std::optional< real >	mass
	Total mass [kg] of the actor.
std::optional< Real6 >	momentOfInertia
	Moment of inertia tensor [kg·m²] at the center of mass in the actor's local frame.
DynamicString	name
	Optional actor name.
GridSdfParams	sdf
	Parameters used to construct a grid-based Signed Distance Field (SDF) if the shape doesn't already have one.
ShapeHandle	shape
	Shape handle defining the actor's geometry and other metadata.
TransformRT	worldFromLocal
	Initial rotation and translation of the actor's local frame with respect to world frame.

Detailed Description

Parameters to create a rigid body actor.

Rigid actors behave as rigid bodies with 6 degrees of freedom (3 translational, 3 rotational). They can be static (fixed in space) or dynamic (affected by forces and collisions).

Note

Also used to create links in articulated bodies.

See also

Scene::CreateRigidActor, ArticulatedActorParams

Definition at line 118 of file mochi_structs.h.

Member Function Documentation

operator==()

bool superdex::RigidActorParams::operator== ( RigidActorParams const & ) const

default

Member Data Documentation

angularVelocity

std::optional<Real3> superdex::RigidActorParams::angularVelocity

Optional initial angular velocity in world frame [rad/s], zero otherwise.

Note

Not valid for static rigid actors or articulated links.

See also

Actor::GetAngularVelocity, Actor::SetVelocity

Definition at line 151 of file mochi_structs.h.

boundaryElementType

ActorBoundaryElementType superdex::RigidActorParams::boundaryElementType = ActorBoundaryElementType::Default

Finite element type for boundary discretization.

Note

Affects accuracy and performance of contact and boundary integrals.

See also

ActorBoundaryElementType

Definition at line 145 of file mochi_structs.h.

boundarySubsampling

std::optional<BoundarySubsamplingParams> superdex::RigidActorParams::boundarySubsampling

Optional subsampling for boundary integrals such as contact.

Note

Reduces computational cost by using fewer sample points.

For best performance, combine subsampling with boundaryElementType = ActorBoundaryElementType::P1Q1.

See also

BoundarySubsamplingParams

Definition at line 147 of file mochi_structs.h.

centerOfMass

std::optional<Real3> superdex::RigidActorParams::centerOfMass

Position [m] of the center of mass in the actor's local frame.

Note

If not set, computed automatically from geometry.

Usually combined with explicit momentOfInertia.

See also

momentOfInertia

Definition at line 141 of file mochi_structs.h.

colliderType

ColliderType superdex::RigidActorParams::colliderType = ColliderType::Auto

Collision detection geometry.

Note

Determines how OTHER actors detect contact with this actor. It does not affect how this actor detects contact with other actors.

See also

ColliderType

Definition at line 127 of file mochi_structs.h.

contact

ContactParams superdex::RigidActorParams::contact

Contact mechanics parameters.

See also

ContactParams

Definition at line 131 of file mochi_structs.h.

density

std::optional<real> superdex::RigidActorParams::density

Uniform density [kg/m³] of the actor.

Must be positive if provided.

Note

Setting both density and mass is not recommended. If both are set, mass takes precedence and density is ignored.

If only density is set, mass is computed automatically from volume.

If neither is set, kDefaultDensity is used.

See also

mass

Definition at line 137 of file mochi_structs.h.

hasGravity

bool superdex::RigidActorParams::hasGravity = true

If true, actor is affected by gravity.

See also

Scene::SetGravity

Definition at line 135 of file mochi_structs.h.

isStatic

bool superdex::RigidActorParams::isStatic = false

If true, actor will be static (fixed in space).

If false, actor will be dynamic.

Definition at line 129 of file mochi_structs.h.

layer

DynamicString superdex::RigidActorParams::layer

Contact layer name for filtering contacts between actors.

See also

Scene::EnableLayerContactAsymmetric, Scene::EnableLayerContactSymmetric, Scene::EnableActorContactAsymmetric, Scene::EnableActorContactSymmetric

Definition at line 121 of file mochi_structs.h.

linearVelocity

std::optional<Real3> superdex::RigidActorParams::linearVelocity

Optional initial linear velocity of the center of mass in world frame [m/s], zero otherwise.

Note

Not valid for static rigid actors or articulated links.

See also

Actor::GetLinearVelocity, Actor::SetVelocity

Definition at line 149 of file mochi_structs.h.

mass

std::optional<real> superdex::RigidActorParams::mass

Total mass [kg] of the actor.

Must be positive if provided.

Note

Setting both mass and density is not recommended. If both are set, mass takes precedence and density is ignored.

If only mass is set, density is computed automatically from volume.

See also

density

Definition at line 139 of file mochi_structs.h.

momentOfInertia

std::optional<Real6> superdex::RigidActorParams::momentOfInertia

Moment of inertia tensor [kg·m²] at the center of mass in the actor's local frame.

Stored as [ixx, ixy, ixz, iyy, iyz, izz] using negative tensor notation:

    [ixx, ixy, ixz]   [ +∫(y²+z²)dm,  -∫(xy)dm,    -∫(xz)dm    ]
I = [ixy, iyy, iyz] = [ -∫(xy)dm,     +∫(x²+z²)dm, -∫(yz)dm    ]
    [ixz, iyz, izz]   [ -∫(xz)dm,     -∫(yz)dm,    +∫(x²+y²)dm ]

Note

Uses negative tensor notation consistent with e.g. robotics URDF files.

Many CAD tools (e.g., Solidworks) use positive tensor notation requiring negation of off-diagonal terms. See https://www.mathworks.com/help/sm/ug/specify-custom-inertia.html.

Must be finite. A finite but physically invalid tensor (negative principal moments or one violating the triangle inequality) is accepted with a warning, not rejected.

If not set, computed automatically from geometry and density.

Usually combined with explicit centerOfMass.

See also

centerOfMass

Definition at line 143 of file mochi_structs.h.

name

DynamicString superdex::RigidActorParams::name

Optional actor name.

Uniqueness of names is not enforced.

Definition at line 119 of file mochi_structs.h.

sdf

GridSdfParams superdex::RigidActorParams::sdf

Parameters used to construct a grid-based Signed Distance Field (SDF) if the shape doesn't already have one.

Note

Ignored if colliderType is not ColliderType::Sdf.

Ignored if the shape already has a grid-based SDF.

Definition at line 133 of file mochi_structs.h.

shape

ShapeHandle superdex::RigidActorParams::shape

Shape handle defining the actor's geometry and other metadata.

Note

A shape can be shared by multiple actors, even actors in different scenes.

Dynamic rigid actors require a shape with a surface mesh.

See also

ShapeHandle, Context::LoadShapeFromFile

Definition at line 123 of file mochi_structs.h.

worldFromLocal

TransformRT superdex::RigidActorParams::worldFromLocal

Initial rotation and translation of the actor's local frame with respect to world frame.

Note

The actor's center of mass may be located elsewhere, since it is not necessarily at the origin of the actor's local coordinate frame.

See also

centerOfMass

Definition at line 125 of file mochi_structs.h.

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The documentation for this struct was generated from the following files:

• mochi_structs.h
• mochi_physics.generated.dox