Table of Contents

Class SolidBody2D

Namespace
Gravitas
Assembly
Gravitas.dll

Represents deterministic pure 2D body state owned by one world context.

public sealed class SolidBody2D : IRecordable
Inheritance
SolidBody2D
Implements
IRecordable
Inherited Members

Constructors

SolidBody2D(IMatterAgent, LSCollider2D)

Creates a pure 2D body bound to a host agent and collider.

public SolidBody2D(IMatterAgent agent, LSCollider2D collider)

Parameters

agent IMatterAgent
collider LSCollider2D

Fields

OnGrounded

Raised when grounded state changes.

public Action<bool>? OnGrounded

Field Value

Action<bool>

Properties

Active

Gets whether the body is initialized and registered.

public bool Active { get; }

Property Value

bool

Agent

Gets the host agent that owns this body.

public IMatterAgent Agent { get; }

Property Value

IMatterAgent

AngularAcceleration

Gets the accumulated yaw acceleration.

public Fixed64 AngularAcceleration { get; }

Property Value

Fixed64

AngularSpeed

Gets the absolute yaw speed.

public Fixed64 AngularSpeed { get; }

Property Value

Fixed64

AngularVelocity

Gets the signed yaw velocity.

public Fixed64 AngularVelocity { get; }

Property Value

Fixed64

CanRotate

Gets whether solver-side response may rotate this pure 2D body around its yaw axis.

public bool CanRotate { get; }

Property Value

bool

CanTranslate

Gets whether solver-side response may translate this pure 2D body.

public bool CanTranslate { get; }

Property Value

bool

Collider

Gets the runtime 2D collider attached to this body.

public LSCollider2D Collider { get; }

Property Value

LSCollider2D

Context

Gets the world context supplied by the host agent.

public GravitasWorldContext Context { get; }

Property Value

GravitasWorldContext

ContinuousCollisionMode

Selects the deterministic tunneling guard used when this pure 2D body commits frame movement.

public ContinuousCollisionMode ContinuousCollisionMode { get; set; }

Property Value

ContinuousCollisionMode

Exceptions

ArgumentOutOfRangeException

The value is not a declared continuous-collision mode.

DynamicId

Gets the ephemeral simulated-body slot, or -1 for a static or unregistered body.

public int DynamicId { get; }

Property Value

int

EffectiveInverseMass

Gets the inverse mass that should be used by pure 2D and mixed response.

public Fixed64 EffectiveInverseMass { get; }

Property Value

Fixed64

EffectiveInverseMomentOfInertia

Gets the inverse scalar moment that should be used by pure 2D angular response.

public Fixed64 EffectiveInverseMomentOfInertia { get; }

Property Value

Fixed64

FreezeAxes

Gets or sets the planar translational and yaw rotational degrees of freedom frozen for pure 2D solver response, integration, CCD, and rotational CCD.

public BodyFreezeAxes2D FreezeAxes { get; set; }

Property Value

BodyFreezeAxes2D

Gravity

Gets or sets the planar gravity acceleration applied to this body.

public Vector2d Gravity { get; set; }

Property Value

Vector2d

GravityScale

Multiplies this body's planar gravity vector. Zero disables body-authored gravity acceleration.

public Fixed64 GravityScale { get; set; }

Property Value

Fixed64

GroundDownDistanceOnAir

Probe distance used while the body is airborne.

public Fixed64 GroundDownDistanceOnAir { get; set; }

Property Value

Fixed64

GroundMinNormalDot

Minimum dot product between a candidate support normal and resolved up direction.

public Fixed64 GroundMinNormalDot { get; set; }

Property Value

Fixed64

GroundNormal

Gets the current support normal in the X/Z simulation plane.

public Vector2d GroundNormal { get; }

Property Value

Vector2d

GroundPoint

Gets the current support point in the X/Z simulation plane.

public Vector2d GroundPoint { get; }

Property Value

Vector2d

Exceptions

InvalidOperationException

No grounded point is available or the conceptual contact point is outside the scalar range.

GroundProbeMode

Selects the pure 2D query primitive used when probing for planar support.

public GroundProbeMode2D GroundProbeMode { get; set; }

Property Value

GroundProbeMode2D

GroundProbeRadius

Optional explicit radius for swept-circle support probes. A zero value derives the radius from the collider.

public Fixed64 GroundProbeRadius { get; set; }

Property Value

Fixed64

GroundUpDirection

Gets or sets the fallback support up direction in the X/Z simulation plane.

public Vector2d GroundUpDirection { get; set; }

Property Value

Vector2d

GroundedDistanceRay

Probe distance used while the body is already grounded.

public Fixed64 GroundedDistanceRay { get; set; }

Property Value

Fixed64

GroundingMode

Selects whether Gravitas owns planar support detection or preserves host-supplied state.

public GroundingMode GroundingMode { get; }

Property Value

GroundingMode

HasGroundPoint

Gets whether the current support point can be represented in the X/Z simulation plane.

public bool HasGroundPoint { get; }

Property Value

bool

InverseMass

Gets the reciprocal mass, or zero when the mass is non-positive.

public Fixed64 InverseMass { get; }

Property Value

Fixed64

InverseMomentOfInertia

Gets the reciprocal yaw moment of inertia.

public Fixed64 InverseMomentOfInertia { get; }

Property Value

Fixed64

IsDynamic

Gets whether the solver controls this body.

public bool IsDynamic { get; }

Property Value

bool

IsGrounded

Gets whether this body currently has planar support.

public bool IsGrounded { get; }

Property Value

bool

IsKinematic

Gets whether the host controls this body's pose.

public bool IsKinematic { get; }

Property Value

bool

IsPositionFullyFrozen

Gets whether both planar translation axes are frozen.

public bool IsPositionFullyFrozen { get; }

Property Value

bool

IsRotationFullyFrozen

Gets whether pure 2D yaw rotation is frozen.

public bool IsRotationFullyFrozen { get; }

Property Value

bool

IsSleeping

Gets whether the body is sleeping.

public bool IsSleeping { get; }

Property Value

bool

IsStatic

Gets whether this body is excluded from per-frame motion.

public bool IsStatic { get; }

Property Value

bool

LastContinuousCollisionToiIterationCount

Gets the number of continuous-collision impacts consumed by the most recent 2D late simulation step.

public int LastContinuousCollisionToiIterationCount { get; }

Property Value

int

LastContinuousCollisionToiIterationLimitReached

Gets whether the most recent 2D late simulation step reached the configured continuous-collision TOI iteration limit.

public bool LastContinuousCollisionToiIterationLimitReached { get; }

Property Value

bool

LastGroundedPosition

Gets the body position captured when the current support state was accepted.

public Vector2d LastGroundedPosition { get; }

Property Value

Vector2d

LinearSpeed

Gets the magnitude of LinearVelocity.

public Fixed64 LinearSpeed { get; }

Property Value

Fixed64

LinearVelocity

Gets the authoritative planar linear velocity.

public Vector2d LinearVelocity { get; }

Property Value

Vector2d

LocalCenterOfMassOffset

Gets or sets the authoritative body-local center-of-mass offset in the X/Z simulation plane.

public Vector2d LocalCenterOfMassOffset { get; set; }

Property Value

Vector2d

Mass

Gets or sets the body mass used to derive solver mass properties.

public Fixed64 Mass { get; set; }

Property Value

Fixed64

MomentOfInertia

Gets the scalar moment of inertia around the yaw axis.

public Fixed64 MomentOfInertia { get; }

Property Value

Fixed64

MotionType

Gets this body's explicit solver-controlled, host-controlled, or static runtime role.

public BodyMotionType MotionType { get; }

Property Value

BodyMotionType

Position

Gets the authoritative planar X/Z position.

public Vector2d Position { get; }

Property Value

Vector2d

Rotation

Gets the authoritative yaw rotation.

public Fixed64 Rotation { get; }

Property Value

Fixed64

SleepAngularSpeedThreshold

Angular speed at or below which the body can count toward sleeping.

public Fixed64 SleepAngularSpeedThreshold { get; set; }

Property Value

Fixed64

SleepEnabled

Enables deterministic sleep evaluation for this body. Disabling sleep wakes a sleeping body immediately.

public bool SleepEnabled { get; set; }

Property Value

bool

SleepFrameThreshold

Number of consecutive fixed frames below sleep thresholds required before the body sleeps.

public int SleepFrameThreshold { get; set; }

Property Value

int

SleepLinearSpeedThreshold

Linear speed at or below which the body can count toward sleeping.

public Fixed64 SleepLinearSpeedThreshold { get; set; }

Property Value

Fixed64

UseGravityDerivedGroundUpDirection

Gets or sets whether non-zero planar gravity defines the support up direction.

public bool UseGravityDerivedGroundUpDirection { get; set; }

Property Value

bool

WasGrounded

Gets whether this body was grounded before the latest authoritative grounding refresh or manual grounding change.

public bool WasGrounded { get; }

Property Value

bool

WorldCenterOfMass

Gets the authoritative world-space center of mass in the X/Z simulation plane.

public Vector2d WorldCenterOfMass { get; }

Property Value

Vector2d

Exceptions

InvalidOperationException

The center lies outside the representable coordinate domain. Use TryGetWorldCenterOfMass(out Vector2d) when that is possible.

Methods

AddAngularImpulse(Fixed64)

Applies an immediate yaw-velocity change derived from the supplied angular impulse and inverse moment of inertia. The impulse is expressed in mass-distance-squared-per-time units and does not apply a time-step factor.

public void AddAngularImpulse(Fixed64 impulse)

Parameters

impulse Fixed64

The signed yaw impulse applied to the body.

AddForce(Vector2d)

Queues a planar force in mass-distance-per-time-squared units for integration during the next fixed step.

public void AddForce(Vector2d force)

Parameters

force Vector2d

The X/Z-plane force to apply.

AddLinearImpulse(Vector2d)

Applies an X/Z-plane linear impulse immediately as a velocity change. The impulse is expressed in mass-distance-per-time units and does not advance the fixed-step simulation or apply a time-step factor.

public void AddLinearImpulse(Vector2d impulse)

Parameters

impulse Vector2d

The planar linear impulse to apply.

AddTorque(Fixed64)

Queues a yaw torque in mass-distance-squared-per-time-squared units for integration during the next fixed step.

public void AddTorque(Fixed64 torque)

Parameters

torque Fixed64

The signed yaw torque applied to the body.

CheckGround()

Forces an immediate automatic support probe when Gravitas owns grounding.

public void CheckGround()

ClearManualGrounding()

Clears host-owned planar grounded state while leaving automatic support disabled.

public void ClearManualGrounding()

Deactivate()

Removes this body and its collider from the pure 2D runtime service.

public void Deactivate()

GetLocalPoint(Vector2d)

Gets a body-local point from the authoritative 2D body pose and committed collider scale.

public Vector2d GetLocalPoint(Vector2d point)

Parameters

point Vector2d

Returns

Vector2d

GetWorldPoint(Vector2d)

Gets a world-space point from the authoritative 2D body pose and committed collider scale.

public Vector2d GetWorldPoint(Vector2d point)

Parameters

point Vector2d

Returns

Vector2d

Initialize(Vector2d, Fixed64, BodyMotionType)

Initializes and registers the body at an authoritative planar pose.

public void Initialize(Vector2d position, Fixed64 rotation = default, BodyMotionType motionType = BodyMotionType.Dynamic)

Parameters

position Vector2d
rotation Fixed64
motionType BodyMotionType

RecordData(IChronicler)

Records or restores deterministic body state through Chronicler.

public void RecordData(IChronicler chronicler)

Parameters

chronicler IChronicler

ResetCenterOfMassFromCollider()

Clears an explicit center-of-mass override and derives the offset from the bound collider again.

public void ResetCenterOfMassFromCollider()

ResetPosition(Vector2d, Fixed64)

Resets authoritative 2D pose and clears accumulated linear/angular motion for deterministic fixture reuse.

public void ResetPosition(Vector2d position = default, Fixed64 rotation = default)

Parameters

position Vector2d

The new X/Z-plane position.

rotation Fixed64

The new yaw rotation in radians.

SetManualGrounding(Vector2d, Vector2d)

Sets host-owned planar grounded state for manual support sources such as deterministic tilemaps.

public void SetManualGrounding(Vector2d groundPoint, Vector2d groundNormal)

Parameters

groundPoint Vector2d
groundNormal Vector2d

SetMotionType(BodyMotionType)

Changes this registered body's runtime role between fixed-step transactions.

public void SetMotionType(BodyMotionType motionType)

Parameters

motionType BodyMotionType

Remarks

The transition preserves body, collider, pair, joint, and host identity, but clears incompatible motion, sleep, CCD, and solver-cache state before repartitioning. Freeze axes remain independent of the selected role.

Exceptions

ArgumentOutOfRangeException

motionType is undefined.

InvalidOperationException

The body is not currently registered, its context registration has been reset, or a simulation transaction or callback is active.

SetPosition(Vector2d)

Sets the authoritative planar position and refreshes collider state.

public void SetPosition(Vector2d position)

Parameters

position Vector2d

SetRotation(Fixed64)

Sets the authoritative yaw rotation and refreshes collider state.

public void SetRotation(Fixed64 rotation)

Parameters

rotation Fixed64

Sleep()

Puts an eligible body to sleep and clears its motion.

public void Sleep()

TryGetGroundPoint(out Vector2d)

Attempts to get the current support point.

public bool TryGetGroundPoint(out Vector2d point)

Parameters

point Vector2d

Returns

bool

TryGetLocalPoint(Vector2d, out Vector2d)

Attempts to get a body-local point from the authoritative 2D body pose and committed collider scale.

public bool TryGetLocalPoint(Vector2d point, out Vector2d result)

Parameters

point Vector2d
result Vector2d

Returns

bool

TryGetWorldCenterOfMass(out Vector2d)

Attempts to materialize the authoritative world-space center of mass without saturation.

public bool TryGetWorldCenterOfMass(out Vector2d center)

Parameters

center Vector2d

Returns

bool

TryGetWorldPoint(Vector2d, out Vector2d)

Attempts to get a world-space point from the authoritative 2D body pose and committed collider scale.

public bool TryGetWorldPoint(Vector2d point, out Vector2d result)

Parameters

point Vector2d
result Vector2d

Returns

bool

UseAutomaticGrounding(bool)

Returns grounded-state ownership to Gravitas and optionally refreshes support immediately.

public void UseAutomaticGrounding(bool checkGroundImmediately = true)

Parameters

checkGroundImmediately bool

UseManualGrounding(bool)

Gives the host ownership of grounded state and disables automatic support refresh.

public void UseManualGrounding(bool clearGrounding = true)

Parameters

clearGrounding bool

Wake()

Wakes the body and resumes collision participation.

public void Wake()
Edit this page