PxSceneDesc Class Reference
[Physics]

Descriptor class for scenes. See PxScene. More...

#include <PxSceneDesc.h>

Collaboration diagram for PxSceneDesc:


Public Member Functions
PX_INLINE	PxSceneDesc (const PxTolerancesScale &scale)
	constructor sets to default.
PX_INLINE void	setToDefault (const PxTolerancesScale &scale)
	(re)sets the structure to the default.
PX_INLINE bool	isValid () const
	Returns true if the descriptor is valid.
Public Attributes
PxVec3	gravity
	Gravity vector.
PxSimulationEventCallback *	simulationEventCallback
	Possible notification callback.
PxContactModifyCallback *	contactModifyCallback
	Possible asynchronous callback for contact modification.
PxCCDContactModifyCallback *	ccdContactModifyCallback
	Possible asynchronous callback for contact modification.
const void *	filterShaderData
	Shared global filter data which will get passed into the filter shader.
PxU32	filterShaderDataSize
	Size (in bytes) of the shared global filter data filterShaderData.
PxSimulationFilterShader	filterShader
	The custom filter shader to use for collision filtering.
PxSimulationFilterCallback *	filterCallback
	A custom collision filter callback which can be used to implement more complex filtering operations which need access to the simulation state, for example.
PxBroadPhaseType::Enum	broadPhaseType
	Selects the broad-phase algorithm to use.
PxBroadPhaseCallback *	broadPhaseCallback
	Broad-phase callback.
PxSceneLimits	limits
	Expected scene limits.
PxFrictionType::Enum	frictionType
	Selects the friction algorithm to use for simulation.
PxReal	bounceThresholdVelocity
	A contact with a relative velocity below this will not bounce. A typical value for simulation. stability is about 0.2 * gravity.
PxReal	frictionOffsetThreshold
	A threshold of contact separation distance used to decide if a contact point will experience friction forces.
PxReal	ccdMaxSeparation
	A threshold for speculative CCD. Used to control whether bias, restitution or a combination of the two are used to resolve the contacts.
PxReal	solverOffsetSlop
	A slop value used to zero contact offsets from the body's COM on an axis if the offset along that axis is smaller than this threshold. Can be used to compensate for small numerical errors in contact generation.
PxSceneFlags	flags
	Flags used to select scene options.
PxCpuDispatcher *	cpuDispatcher
	The CPU task dispatcher for the scene.
PxGpuDispatcher *	gpuDispatcher
	The GPU task dispatcher for the scene.
PxPruningStructureType::Enum	staticStructure
	Defines the structure used to store static objects.
PxPruningStructureType::Enum	dynamicStructure
	Defines the structure used to store dynamic objects.
PxU32	dynamicTreeRebuildRateHint
	Hint for how much work should be done per simulation frame to rebuild the pruning structure.
void *	userData
	Will be copied to PxScene::userData.
PxU32	solverBatchSize
	Defines the number of actors required to spawn a separate rigid body solver island task chain.
PxU32	nbContactDataBlocks
	Setting to define the number of 16K blocks that will be initially reserved to store contact, friction, and contact cache data. This is the number of 16K memory blocks that will be automatically allocated from the user allocator when the scene is instantiated. Further 16k memory blocks may be allocated during the simulation up to maxNbContactDataBlocks.
PxU32	maxNbContactDataBlocks
	Setting to define the maximum number of 16K blocks that can be allocated to store contact, friction, and contact cache data. As the complexity of a scene increases, the SDK may require to allocate new 16k blocks in addition to the blocks it has already allocated. This variable controls the maximum number of blocks that the SDK can allocate.
PxReal	maxBiasCoefficient
	The maximum bias coefficient used in the constraint solver.
PxU32	contactReportStreamBufferSize
	Size of the contact report stream (in bytes).
PxU32	ccdMaxPasses
	Maximum number of CCD passes.
PxReal	wakeCounterResetValue
	The wake counter reset value.
PxBounds3	sanityBounds
	The bounds used to sanity check user-set positions of actors and articulation links.
PxgDynamicsMemoryConfig	gpuDynamicsConfig
	The pre-allocations performed in the GPU dynamics pipeline.
PxU32	gpuMaxNumPartitions
	Limitation for the partitions in the GPU dynamics pipeline. This variable must be power of 2. A value greater than 32 is currently not supported. Range: (1, 32) .
PxU32	gpuComputeVersion
	Defines which compute version the GPU dynamics should target. DO NOT MODIFY.

Detailed Description

Descriptor class for scenes. See PxScene.

This struct must be initialized with the same PxTolerancesScale values used to initialize PxPhysics.

See also:: PxScene PxPhysics.createScene PxTolerancesScale

Member Data Documentation

PxReal PxSceneDesc::bounceThresholdVelocity

A contact with a relative velocity below this will not bounce. A typical value for simulation. stability is about 0.2 * gravity.

Range: [0, PX_MAX_F32)
Default: 0.2 * PxTolerancesScale::speed

See also:: PxMaterial

Referenced by isValid().

PxBroadPhaseCallback* PxSceneDesc::broadPhaseCallback

Broad-phase callback.

This callback will be associated with the client PX_DEFAULT_CLIENT. Please use PxScene::setBroadPhaseCallback() to register callbacks for other clients.

Default: NULL

See also:: PxBroadPhaseCallback

PxBroadPhaseType::Enum PxSceneDesc::broadPhaseType

Selects the broad-phase algorithm to use.

Default: PxBroadPhaseType::eSAP

See also:: PxBroadPhaseType

PxCCDContactModifyCallback* PxSceneDesc::ccdContactModifyCallback

Possible asynchronous callback for contact modification.

Default: NULL

See also:: PxContactModifyCallback PxScene.setContactModifyCallback() PxScene.getContactModifyCallback()

PxU32 PxSceneDesc::ccdMaxPasses

Maximum number of CCD passes.

The CCD performs multiple passes, where each pass every object advances to its time of first impact. This value defines how many passes the CCD system should perform.

Note:: The CCD system is a multi-pass best-effort conservative advancement approach. After the defined number of passes has been completed, any remaining time is dropped.
This defines the maximum number of passes the CCD can perform. It may perform fewer if additional passes are not necessary.

Default: 1 Range: [1, PX_MAX_U32]

PxReal PxSceneDesc::ccdMaxSeparation

A threshold for speculative CCD. Used to control whether bias, restitution or a combination of the two are used to resolve the contacts.

Note:: This only has any effect on contacting pairs where one of the bodies has PxRigidBodyFlag::eENABLE_SPECULATIVE_CCD raised.

Range: [0, PX_MAX_F32)
Default: 0.04 * PxTolerancesScale::length

Referenced by isValid().

PxContactModifyCallback* PxSceneDesc::contactModifyCallback

Possible asynchronous callback for contact modification.

Default: NULL

See also:: PxContactModifyCallback PxScene.setContactModifyCallback() PxScene.getContactModifyCallback()

PxU32 PxSceneDesc::contactReportStreamBufferSize

Size of the contact report stream (in bytes).

The contact report stream buffer is used during the simulation to store all the contact reports. If the size is not sufficient, the buffer will grow by a factor of two. It is possible to disable the buffer growth by setting the flag PxSceneFlag::eDISABLE_CONTACT_REPORT_BUFFER_RESIZE. In that case the buffer will not grow but contact reports not stored in the buffer will not get sent in the contact report callbacks.

Default: 8192

Range: (0, PX_MAX_U32]

Referenced by isValid().

PxCpuDispatcher* PxSceneDesc::cpuDispatcher

The CPU task dispatcher for the scene.

See PxCpuDispatcher, PxScene::getCpuDispatcher

Referenced by isValid().

PxPruningStructureType::Enum PxSceneDesc::dynamicStructure

Defines the structure used to store dynamic objects.

PxU32 PxSceneDesc::dynamicTreeRebuildRateHint

Hint for how much work should be done per simulation frame to rebuild the pruning structure.

This parameter gives a hint on the distribution of the workload for rebuilding the dynamic AABB tree pruning structure PxPruningStructureType::eDYNAMIC_AABB_TREE. It specifies the desired number of simulation frames the rebuild process should take. Higher values will decrease the workload per frame but the pruning structure will get more and more outdated the longer the rebuild takes (which can make scene queries less efficient).

Note:: Only used for PxPruningStructureType::eDYNAMIC_AABB_TREE pruning structure.
This parameter gives only a hint. The rebuild process might still take more or less time depending on the number of objects involved.

Range: [4, PX_MAX_U32)
Default: 100

Referenced by isValid().

PxSimulationFilterCallback* PxSceneDesc::filterCallback

A custom collision filter callback which can be used to implement more complex filtering operations which need access to the simulation state, for example.

Default: NULL

See also:: PxSimulationFilterCallback

PxSimulationFilterShader PxSceneDesc::filterShader

The custom filter shader to use for collision filtering.

Note:: This parameter is compulsory. If you don't want to define your own filter shader you can use the default shader PxDefaultSimulationFilterShader which can be found in the PhysX extensions library.

See also:: PxSimulationFilterShader

Referenced by isValid().

const void* PxSceneDesc::filterShaderData

Shared global filter data which will get passed into the filter shader.

Note:: The provided data will get copied to internal buffers and this copy will be used for filtering calls.

Default: NULL

See also:: PxSimulationFilterShader PxScene::setFilterShaderData()

Referenced by isValid().

PxU32 PxSceneDesc::filterShaderDataSize

Size (in bytes) of the shared global filter data filterShaderData.

Default: 0

See also:: PxSimulationFilterShader filterShaderData

Referenced by isValid().

PxSceneFlags PxSceneDesc::flags

Flags used to select scene options.

See also:: PxSceneFlag PxSceneFlags

Referenced by isValid().

PxReal PxSceneDesc::frictionOffsetThreshold

A threshold of contact separation distance used to decide if a contact point will experience friction forces.

Note:

If the separation distance of a contact point is greater than the threshold then the contact point will not experience friction forces.

If the aggregated contact offset of a pair of shapes is large it might be desirable to neglect friction for contact points whose separation distance is sufficiently large that the shape surfaces are clearly separated.

This parameter can be used to tune the separation distance of contact points at which friction starts to have an effect.

Range: [0, PX_MAX_F32)
Default: 0.04 * PxTolerancesScale::length

Referenced by isValid().

PxFrictionType::Enum PxSceneDesc::frictionType

Selects the friction algorithm to use for simulation.

Note:: frictionType cannot be modified after the first call to any of PxScene::simulate, PxScene::solve and PxScene::collide

See also:: PxFrictionType Default: PxFrictionType::ePATCH
PxScene::setFrictionType, PxScene::getFrictionType

PxU32 PxSceneDesc::gpuComputeVersion

Defines which compute version the GPU dynamics should target. DO NOT MODIFY.

PxGpuDispatcher* PxSceneDesc::gpuDispatcher

The GPU task dispatcher for the scene.

Platform specific: Applies to PC GPU only.

See PxGpuDispatcher, PxScene::getGpuDispatcher

PxgDynamicsMemoryConfig PxSceneDesc::gpuDynamicsConfig

The pre-allocations performed in the GPU dynamics pipeline.

PxU32 PxSceneDesc::gpuMaxNumPartitions

Limitation for the partitions in the GPU dynamics pipeline. This variable must be power of 2. A value greater than 32 is currently not supported. Range: (1, 32)
.

Referenced by isValid().

PxVec3 PxSceneDesc::gravity

Gravity vector.

Range: force vector
Default: Zero

See also:: PxScene.setGravity()

When setting gravity, you should probably also set bounce threshold.

PxSceneLimits PxSceneDesc::limits

Expected scene limits.

See also:: PxSceneLimits

Referenced by isValid().

PxReal PxSceneDesc::maxBiasCoefficient

The maximum bias coefficient used in the constraint solver.

When geometric errors are found in the constraint solver, either as a result of shapes penetrating or joints becoming separated or violating limits, a bias is introduced in the solver position iterations to correct these errors. This bias is proportional to 1/dt, meaning that the bias becomes increasingly strong as the time-step passed to PxScene::simulate(...) becomes smaller. This coefficient allows the application to restrict how large the bias coefficient is, to reduce how violent error corrections are. This can improve simulation quality in cases where either variable time-steps or extremely small time-steps are used.

Default: PX_MAX_F32

Range [0, PX_MAX_F32]

PxU32 PxSceneDesc::maxNbContactDataBlocks

Setting to define the maximum number of 16K blocks that can be allocated to store contact, friction, and contact cache data. As the complexity of a scene increases, the SDK may require to allocate new 16k blocks in addition to the blocks it has already allocated. This variable controls the maximum number of blocks that the SDK can allocate.

In the case that the scene is sufficiently complex that all the permitted 16K blocks are used, contacts will be dropped and a warning passed to the error stream.

If a warning is reported to the error stream to indicate the number of 16K blocks is insufficient for the scene complexity then the choices are either (i) re-tune the number of 16K data blocks until a number is found that is sufficient for the scene complexity, (ii) to simplify the scene or (iii) to opt to not increase the memory requirements of physx and accept some dropped contacts.

Default: 65536

Range: [0, PX_MAX_U32]

See also:: nbContactDataBlocks PxScene::setNbContactDataBlocks

Referenced by isValid().

PxU32 PxSceneDesc::nbContactDataBlocks

Setting to define the number of 16K blocks that will be initially reserved to store contact, friction, and contact cache data. This is the number of 16K memory blocks that will be automatically allocated from the user allocator when the scene is instantiated. Further 16k memory blocks may be allocated during the simulation up to maxNbContactDataBlocks.

Note:: This value cannot be larger than maxNbContactDataBlocks because that defines the maximum number of 16k blocks that can be allocated by the SDK.

Default: 0

Range: [0, PX_MAX_U32]

See also:: PxPhysics::createScene PxScene::setNbContactDataBlocks

Referenced by isValid().

PxBounds3 PxSceneDesc::sanityBounds

The bounds used to sanity check user-set positions of actors and articulation links.

These bounds are used to check the position values of rigid actors inserted into the scene, and positions set for rigid actors already within the scene.

Range: any valid PxBounds3
Default: (-PX_MAX_BOUNDS_EXTENTS, PX_MAX_BOUNDS_EXTENTS) on each axis

Referenced by isValid().

PxSimulationEventCallback* PxSceneDesc::simulationEventCallback

Possible notification callback.

This callback will be associated with the client PX_DEFAULT_CLIENT. Please use PxScene::setSimulationEventCallback() to register callbacks for other clients.

Default: NULL

See also:: PxSimulationEventCallback PxScene.setSimulationEventCallback() PxScene.getSimulationEventCallback()

PxU32 PxSceneDesc::solverBatchSize

Defines the number of actors required to spawn a separate rigid body solver island task chain.

This parameter defines the minimum number of actors required to spawn a separate rigid body solver task chain. Setting a low value will potentially cause more task chains to be generated. This may result in the overhead of spawning tasks can become a limiting performance factor. Setting a high value will potentially cause fewer islands to be generated. This may reduce thread scaling (fewer task chains spawned) and may detrimentally affect performance if some bodies in the scene have large solver iteration counts because all constraints in a given island are solved by the maximum number of solver iterations requested by any body in the island.

Default: 128

See also:: PxScene.setSolverBatchSize() PxScene.getSolverBatchSize()

PxReal PxSceneDesc::solverOffsetSlop

A slop value used to zero contact offsets from the body's COM on an axis if the offset along that axis is smaller than this threshold. Can be used to compensate for small numerical errors in contact generation.

Range: [0, PX_MAX_F32)
Default: 0.0

PxPruningStructureType::Enum PxSceneDesc::staticStructure

Defines the structure used to store static objects.