PxSceneDesc Class Reference
[Physics]

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

#include <PxSceneDesc.h>

Collaboration diagram for PxSceneDesc:

[legend]

List of all members.

Public Member Functions
PX_INLINE	PxSceneDesc (const PxTolerancesScale &scale)
	constructor sets to default (no gravity, no ground plane, collision detection on).
PX_INLINE void	setToDefault (const PxTolerancesScale &scale)
	(re)sets the structure to the default (no gravity, no ground plane, collision detection on).
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.
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.
PxSceneLimits	limits
	Expected scene limits.
PxReal	sweepEpsilonDistance
	A small epsilon value used for swept collision detection.
PxReal	contactCorrelationDistance
	Two contacts are considered to be identical if their distance is below this value.
PxReal	bounceThresholdVelocity
	A contact with a relative velocity below this will not bounce. A typical value for simulation stability is about 0.2 * gravity.
PxSceneFlags	flags
	Flags used to select scene options.
pxtask::CpuDispatcher *	cpuDispatcher
	The CPU task dispatcher for the scene.
pxtask::GpuDispatcher *	gpuDispatcher
	The GPU task dispatcher for the scene.
pxtask::SpuDispatcher *	spuDispatcher
	The SPU task dispatcher for the scene.
PxPruningStructure::Enum	staticStructure
	Defines the structure used to store static objects.
PxPruningStructure::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 thread.
PxReal	sweptIntegrationLinearSpeedFactor
	Setting to determine how fast an object has to translate to perform swept integration.
PxReal	sweptIntegrationAngularSpeedFactor
	Setting to determine how fast an object has to rotate to perform swept integration.
PxU32	nbContactDataBlocks
	Setting to determine how many 16K blocks are initially reserved to store contact, friction, and contact cache data. Memory blocks, each 16K, will be automatically allocated from the user allocator when the scene is instantiated. The initial number of 16K allocations is controlled by nbContactDataBlocks. In the case that the scene is sufficiently complex that all 16K blocks are used, contacts will be dropped and a warning passed to the error stream.
PxU32	maxNbContactDataBlocks
	Setting to determine how many 16K blocks are reserved to store contact, friction, and contact cache data. Memory blocks, each 16K, will be automatically allocated from the user allocator when the scene is instantiated. The maximum number of 16K allocations is controlled by maxNbContactDataBlocks. In the case that the scene is sufficiently complex that all 16K blocks are used, contacts will be dropped and a warning passed to the error stream.
PxU32	contactReportStreamBufferSize
	Size of the contact report stream (in bytes).

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Detailed Description

Descriptor class for scenes. See PxScene.

See also:

PxScene PxPhysics.createScene

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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, inf)
Default: 2

See also:

PxMaterial

Referenced by isValid().

PxReal PxSceneDesc::contactCorrelationDistance

Two contacts are considered to be identical if their distance is below this value.

Making this too small may make contact generation unstable.

Range: [0, inf)
Default: 0.025 * lengthScale

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, inf)

Referenced by isValid().

pxtask::CpuDispatcher* PxSceneDesc::cpuDispatcher

The CPU task dispatcher for the scene.

Platform:

• PC SW: Yes
• PS3 : Yes
• XB360: Yes
• WII : Yes

See pxtask::CpuDispatcher

Referenced by isValid().

PxPruningStructure::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 PxPruningStructure::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 PxPruningStructure::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: [5, inf]
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

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.

Platform:

• PC SW: Yes
• PS3 : Yes
• XB360: Yes
• WII : Yes

See also:

PxSceneFlag PxSceneFlags

pxtask::GpuDispatcher* PxSceneDesc::gpuDispatcher

The GPU task dispatcher for the scene.

Platform:

• PC GPU: Yes
• PC SW : Not applicable
• PS3 : Not applicable
• XB360 : Not applicable
• WII : Not applicable

See pxtask::GpuDispatcher

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().

PxU32 PxSceneDesc::maxNbContactDataBlocks

Setting to determine how many 16K blocks are reserved to store contact, friction, and contact cache data. Memory blocks, each 16K, will be automatically allocated from the user allocator when the scene is instantiated. The maximum number of 16K allocations is controlled by maxNbContactDataBlocks. In the case that the scene is sufficiently complex that all 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 or (ii) to opt to not increase the memory requirements of physx and accept some dropped contacts.

Default: 65536, or 256 on PS3

Range: [0, inf)

See also:

nbContactDataBlocks PxScene::setNbContactDataBlocks

Referenced by isValid().

PxU32 PxSceneDesc::nbContactDataBlocks

Setting to determine how many 16K blocks are initially reserved to store contact, friction, and contact cache data. Memory blocks, each 16K, will be automatically allocated from the user allocator when the scene is instantiated. The initial number of 16K allocations is controlled by nbContactDataBlocks. In the case that the scene is sufficiently complex that all 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 or (ii) to opt to not increase the memory requirements of physx and accept some dropped contacts.

Default: 0, or 256 on PS3

Range: [0, inf)

See also:

PxPhysics::createScene PxScene::setNbContactDataBlocks

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 thread.

Default: 32

Platform:

• PC SW: Yes
• PS3 : Not applicable
• XB360: Yes
• WII : Yes

See also:

PxScene.setSolverBatchSize() PxScene.getSolverBatchSize()

pxtask::SpuDispatcher* PxSceneDesc::spuDispatcher

The SPU task dispatcher for the scene.

Platform:

• PC SW: Not applicable
• PS3 : Yes
• XB360: Not applicable
• WII : Not applicable

See pxtask::SpuDispatcher

PxPruningStructure::Enum PxSceneDesc::staticStructure

Defines the structure used to store static objects.

Note:

Only PxPruningStructure::eSTATIC_AABB_TREE and PxPruningStructure::eDYNAMIC_AABB_TREE are allowed here.

Referenced by isValid().

PxReal PxSceneDesc::sweepEpsilonDistance

A small epsilon value used for swept collision detection.

See also:

PxTolerancesScale Default: 0.01 * lengthScale

Referenced by isValid().

PxReal PxSceneDesc::sweptIntegrationAngularSpeedFactor

Setting to determine how fast an object has to rotate to perform swept integration.

Default: 2

See also:

sweptIntegrationLinearSpeedFactor

Referenced by isValid().

PxReal PxSceneDesc::sweptIntegrationLinearSpeedFactor

Setting to determine how fast an object has to translate to perform swept integration.

For a pair of objects for which swept integration is enabled (see PxPairFlag::eSWEPT_INTEGRATION_LINEAR) swept integration will still be skipped if for both objects the below formula evaluates to false:

isMovingFast = smallest < (linearVelocity.magnitude() * a + angularVelocity.magnitude() * b * largest )*dt

Where

smallest = bounds.halfDimensions().smallestDimension() largest = bounds.halfDimensions().largestDimension()

a = sweptIntegrationLinearSpeedFactor b = sweptIntegrationAngularSpeedFactor

a and b default to two because an object must only move half it's size to be considered fast, and this accounts for it.

Default: 2

See also:

sweptIntegrationAngularSpeedFactor

Referenced by isValid().

void* PxSceneDesc::userData

Will be copied to PxScene::userData.

Default: NULL

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

• PxSceneDesc.h