Parameters describing a single rigid link within an articulated actor. More...

#include <mochi_structs.h>

Inheritance diagram for superdex::ArticulatedLinkParams:

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

Public Attributes
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 link 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, the link actor will be affected by gravity.
DynamicString	layer
	Contact layer name for filtering contacts between actors.
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
	Link local name.
TransformRT	parentJointFromLink
	Rotation and translation of the link with respect to the parent joint.
int	parentLink = -1
	Index of the parent link in ArticulatedActorParams::links, or -1 for the root.
ShapeHandle	shape
	Shape handle defining the actor's geometry and other metadata.

Detailed Description

Parameters describing a single rigid link within an articulated actor.

Each link is a rigid body in the articulation's kinematic tree. Mirrors RigidActorParams for the per-link rigid-body properties (shape, mass, inertia, contact), and adds tree-structure fields (parentLink, parentJointFromLink). Pose and velocity at creation time come from the articulated body, not from per-link fields.

See also: ArticulatedActorParams, ArticulatedJointParams, RigidActorParams

Definition at line 201 of file mochi_structs.h.

Member Function Documentation

◆ operator==()

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

default

Member Data Documentation

◆ boundaryElementType

ActorBoundaryElementType superdex::ArticulatedLinkParams::boundaryElementType = ActorBoundaryElementType::Default

Finite element type for boundary discretization.

Note: Affects accuracy and performance of contact and boundary integrals.

Definition at line 214 of file mochi_structs.h.

◆ boundarySubsampling

std::optional<BoundarySubsamplingParams> superdex::ArticulatedLinkParams::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.

Definition at line 215 of file mochi_structs.h.

◆ centerOfMass

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

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

Note: If not set, computed automatically from geometry.; Usually combined with explicit momentOfInertia.

See also: momentOfInertia

Definition at line 212 of file mochi_structs.h.

◆ colliderType

ColliderType superdex::ArticulatedLinkParams::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.

Definition at line 207 of file mochi_structs.h.

◆ contact

ContactParams superdex::ArticulatedLinkParams::contact

Contact mechanics parameters.

Definition at line 208 of file mochi_structs.h.

◆ density

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

Uniform density [kg/m³] of the actor.

Must be positive if provided.

Note: Specify either density or mass, but not both.; If density is set, mass is computed automatically from volume (and vice versa).; If neither is set, kDefaultDensity is used.

See also: mass

Definition at line 210 of file mochi_structs.h.

◆ hasGravity

bool superdex::ArticulatedLinkParams::hasGravity = true

If true, the link actor will be affected by gravity.

See also: Scene::SetGravity

Definition at line 209 of file mochi_structs.h.

◆ layer

DynamicString superdex::ArticulatedLinkParams::layer

Contact layer name for filtering contacts between actors.

See also: Scene::EnableLayerContactAsymmetric, Scene::EnableLayerContactSymmetric, Scene::EnableActorContactAsymmetric, Scene::EnableActorContactSymmetric

Definition at line 206 of file mochi_structs.h.

◆ mass

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

Total mass [kg] of the actor.

Must be positive if provided.

Note: Specify either mass or density, but not both.; If mass is set, density is computed automatically from volume (and vice versa).

See also: density

Definition at line 211 of file mochi_structs.h.

◆ momentOfInertia

std::optional<Real6> superdex::ArticulatedLinkParams::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 213 of file mochi_structs.h.

◆ name

DynamicString superdex::ArticulatedLinkParams::name

Link local name.

Note: Must be unique among links of the same articulated actor. For soft-skinned actors, it must also not collide with nested soft actor local names.; Must not contain forward slash, backslash, or embedded NUL characters, which are reserved for hierarchy paths or incompatible with actor path formatting.; If left empty, a unique default name (e.g., "link_0", "link_1", ...) is assigned automatically.; In the scene the corresponding actor is named "articulatedActorName/linkLocalName". If the articulated actor name is empty, link actors use "unnamed_articulation/linkLocalName".

Definition at line 202 of file mochi_structs.h.

◆ parentJointFromLink

TransformRT superdex::ArticulatedLinkParams::parentJointFromLink

Rotation and translation of the link with respect to the parent joint.

Warning: The rotation must be identity. Non-identity rotations are not supported yet.

Definition at line 204 of file mochi_structs.h.

◆ parentLink

int superdex::ArticulatedLinkParams::parentLink = -1

Index of the parent link in ArticulatedActorParams::links, or -1 for the root.

Note: Links must be listed in parent-first order: parentLink < i for the i-th link.; The root link (index 0) must have parentLink == -1.

Definition at line 203 of file mochi_structs.h.

◆ shape

ShapeHandle superdex::ArticulatedLinkParams::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 links require a shape with a surface mesh when link contact is enabled. An articulated actor enables link contact when no skin shape is provided. A soft-skinned actor enables link contact when SoftSkinnedActorParams::enableCollidingLinks is true.

See also: ShapeHandle, Context::LoadShapeFromFile

Definition at line 205 of file mochi_structs.h.

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

Public Member Functions

Public Attributes