#include <PhysicsSettings.h>

Public Attributes
JPH_OVERRIDE_NEW_DELETE int	mMaxInFlightBodyPairs = 16384

int	mStepListenersBatchSize = 8
	How many PhysicsStepListeners to notify in 1 batch.

int	mStepListenerBatchesPerJob = 1
	How many step listener batches are needed before spawning another job (set to INT_MAX if no parallelism is desired)

float	mBaumgarte = 0.2f
	Baumgarte stabilization factor (how much of the position error to 'fix' in 1 update) (unit: dimensionless, 0 = nothing, 1 = 100%)

float	mSpeculativeContactDistance = 0.02f

float	mPenetrationSlop = 0.02f
	How much bodies are allowed to sink into each other (unit: meters)

float	mLinearCastThreshold = 0.75f
	Fraction of its inner radius a body must move per step to enable casting for the LinearCast motion quality.

float	mLinearCastMaxPenetration = 0.25f
	Fraction of its inner radius a body may penetrate another body for the LinearCast motion quality.

float	mManifoldToleranceSq = 1.0e-6f
	Max squared distance to use to determine if two points are on the same plane for determining the contact manifold between two shape faces (unit: meter^2)

float	mMaxPenetrationDistance = 0.2f
	Maximum distance to correct in a single iteration when solving position constraints (unit: meters)

float	mBodyPairCacheMaxDeltaPositionSq = Square(0.001f)
	Maximum relative delta position for body pairs to be able to reuse collision results from last frame (units: meter^2)

float	mBodyPairCacheCosMaxDeltaRotationDiv2 = 0.99984769515639123915701155881391f
	Maximum relative delta orientation for body pairs to be able to reuse collision results from last frame, stored as cos(max angle / 2)

float	mContactNormalCosMaxDeltaRotation = 0.99619469809174553229501040247389f
	Maximum angle between normals that allows manifolds between different sub shapes of the same body pair to be combined.

float	mContactPointPreserveLambdaMaxDistSq = Square(0.01f)
	Maximum allowed distance between old and new contact point to preserve contact forces for warm start (units: meter^2)

uint	mNumVelocitySteps = 10

uint	mNumPositionSteps = 2
	Number of solver position iterations to run.

float	mMinVelocityForRestitution = 1.0f

float	mTimeBeforeSleep = 0.5f
	Time before object is allowed to go to sleep (unit: seconds)

float	mPointVelocitySleepThreshold = 0.03f

bool	mDeterministicSimulation = true
	By default the simulation is deterministic, it is possible to turn this off by setting this setting to false. This will make the simulation run faster but it will no longer be deterministic.

These variables are mainly for debugging purposes, they allow turning on/off certain subsystems. You probably want to leave them alone.
bool	mConstraintWarmStart = true
	Whether or not to use warm starting for constraints (initially applying previous frames impulses)

bool	mUseBodyPairContactCache = true
	Whether or not to use the body pair cache, which removes the need for narrow phase collision detection when orientation between two bodies didn't change.

bool	mUseManifoldReduction = true
	Whether or not to reduce manifolds with similar contact normals into one contact manifold (see description at Body::SetUseManifoldReduction)

bool	mUseLargeIslandSplitter = true
	If we split up large islands into smaller parallel batches of work (to improve performance)

bool	mAllowSleeping = true
	If objects can go to sleep or not.

bool	mCheckActiveEdges = true
	When false, we prevent collision against non-active (shared) edges. Mainly for debugging the algorithm.

Member Data Documentation

◆ mAllowSleeping

bool PhysicsSettings::mAllowSleeping = true

If objects can go to sleep or not.

◆ mBaumgarte

float PhysicsSettings::mBaumgarte = 0.2f

Baumgarte stabilization factor (how much of the position error to 'fix' in 1 update) (unit: dimensionless, 0 = nothing, 1 = 100%)

◆ mBodyPairCacheCosMaxDeltaRotationDiv2

float PhysicsSettings::mBodyPairCacheCosMaxDeltaRotationDiv2 = 0.99984769515639123915701155881391f

Maximum relative delta orientation for body pairs to be able to reuse collision results from last frame, stored as cos(max angle / 2)

cos(2 degrees / 2)

◆ mBodyPairCacheMaxDeltaPositionSq

float PhysicsSettings::mBodyPairCacheMaxDeltaPositionSq = Square(0.001f)

Maximum relative delta position for body pairs to be able to reuse collision results from last frame (units: meter^2)

1 mm

◆ mCheckActiveEdges

bool PhysicsSettings::mCheckActiveEdges = true

When false, we prevent collision against non-active (shared) edges. Mainly for debugging the algorithm.

◆ mConstraintWarmStart

bool PhysicsSettings::mConstraintWarmStart = true

Whether or not to use warm starting for constraints (initially applying previous frames impulses)

◆ mContactNormalCosMaxDeltaRotation

float PhysicsSettings::mContactNormalCosMaxDeltaRotation = 0.99619469809174553229501040247389f

Maximum angle between normals that allows manifolds between different sub shapes of the same body pair to be combined.

cos(5 degree)

◆ mContactPointPreserveLambdaMaxDistSq

float PhysicsSettings::mContactPointPreserveLambdaMaxDistSq = Square(0.01f)

Maximum allowed distance between old and new contact point to preserve contact forces for warm start (units: meter^2)

1 cm

◆ mDeterministicSimulation

bool PhysicsSettings::mDeterministicSimulation = true

By default the simulation is deterministic, it is possible to turn this off by setting this setting to false. This will make the simulation run faster but it will no longer be deterministic.

◆ mLinearCastMaxPenetration

float PhysicsSettings::mLinearCastMaxPenetration = 0.25f

Fraction of its inner radius a body may penetrate another body for the LinearCast motion quality.

◆ mLinearCastThreshold

float PhysicsSettings::mLinearCastThreshold = 0.75f

Fraction of its inner radius a body must move per step to enable casting for the LinearCast motion quality.

◆ mManifoldToleranceSq

float PhysicsSettings::mManifoldToleranceSq = 1.0e-6f

Max squared distance to use to determine if two points are on the same plane for determining the contact manifold between two shape faces (unit: meter^2)

◆ mMaxInFlightBodyPairs

JPH_OVERRIDE_NEW_DELETE int PhysicsSettings::mMaxInFlightBodyPairs = 16384

Size of body pairs array, corresponds to the maximum amount of potential body pairs that can be in flight at any time. Setting this to a low value will use less memory but slow down simulation as threads may run out of narrow phase work.

◆ mMaxPenetrationDistance

float PhysicsSettings::mMaxPenetrationDistance = 0.2f

Maximum distance to correct in a single iteration when solving position constraints (unit: meters)

◆ mMinVelocityForRestitution

float PhysicsSettings::mMinVelocityForRestitution = 1.0f

Minimal velocity needed before a collision can be elastic. If the relative velocity between colliding objects in the direction of the contact normal is lower than this, the restitution will be zero regardless of the configured value. This lets an object settle sooner. Must be a positive number. (unit: m)

◆ mNumPositionSteps

uint PhysicsSettings::mNumPositionSteps = 2

Number of solver position iterations to run.

◆ mNumVelocitySteps

uint PhysicsSettings::mNumVelocitySteps = 10

Number of solver velocity iterations to run Note that this needs to be >= 2 in order for friction to work (friction is applied using the non-penetration impulse from the previous iteration)

◆ mPenetrationSlop

float PhysicsSettings::mPenetrationSlop = 0.02f

How much bodies are allowed to sink into each other (unit: meters)

◆ mPointVelocitySleepThreshold

float PhysicsSettings::mPointVelocitySleepThreshold = 0.03f

To detect if an object is sleeping, we use 3 points:

The center of mass.
The centers of the faces of the bounding box that are furthest away from the center. The movement of these points is tracked and if the velocity of all 3 points is lower than this value, the object is allowed to go to sleep. Must be a positive number. (unit: m/s)

◆ mSpeculativeContactDistance

float PhysicsSettings::mSpeculativeContactDistance = 0.02f

Radius around objects inside which speculative contact points will be detected. Note that if this is too big you will get ghost collisions as speculative contacts are based on the closest points during the collision detection step which may not be the actual closest points by the time the two objects hit (unit: meters)

◆ mStepListenerBatchesPerJob

int PhysicsSettings::mStepListenerBatchesPerJob = 1

How many step listener batches are needed before spawning another job (set to INT_MAX if no parallelism is desired)

◆ mStepListenersBatchSize

int PhysicsSettings::mStepListenersBatchSize = 8

How many PhysicsStepListeners to notify in 1 batch.

◆ mTimeBeforeSleep

float PhysicsSettings::mTimeBeforeSleep = 0.5f

Time before object is allowed to go to sleep (unit: seconds)

◆ mUseBodyPairContactCache

bool PhysicsSettings::mUseBodyPairContactCache = true

Whether or not to use the body pair cache, which removes the need for narrow phase collision detection when orientation between two bodies didn't change.

◆ mUseLargeIslandSplitter

bool PhysicsSettings::mUseLargeIslandSplitter = true

If we split up large islands into smaller parallel batches of work (to improve performance)

◆ mUseManifoldReduction

bool PhysicsSettings::mUseManifoldReduction = true

Whether or not to reduce manifolds with similar contact normals into one contact manifold (see description at Body::SetUseManifoldReduction)

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

Jolt/Physics/PhysicsSettings.h

Public Attributes