HdEmbreeRenderDelegate Class Reference

Render delegates provide renderer-specific functionality to the render index, the main hydra state management structure. More...

#include <renderDelegate.h>

Inherits HdRenderDelegate.

Public Member Functions
	HdEmbreeRenderDelegate ()
	Render delegate constructor.
	HdEmbreeRenderDelegate (HdRenderSettingsMap const &settingsMap)
	Render delegate constructor.
	~HdEmbreeRenderDelegate () override
	Render delegate destructor.
HdRenderParam *	GetRenderParam () const override
	Return this delegate's render param.
const TfTokenVector &	GetSupportedRprimTypes () const override
	Return a list of which Rprim types can be created by this class's CreateRprim.
const TfTokenVector &	GetSupportedSprimTypes () const override
	Return a list of which Sprim types can be created by this class's CreateSprim.
const TfTokenVector &	GetSupportedBprimTypes () const override
	Return a list of which Bprim types can be created by this class's CreateBprim.
HdResourceRegistrySharedPtr	GetResourceRegistry () const override
	Returns the HdResourceRegistry instance used by this render delegate.
HdRenderSettingDescriptorList	GetRenderSettingDescriptors () const override
	Returns a list of user-configurable render settings.
bool	IsPauseSupported () const override
	Return true to indicate that pausing and resuming are supported.
bool	Pause () override
	Pause background rendering threads.
bool	Resume () override
	Resume background rendering threads.
HdRenderPassSharedPtr	CreateRenderPass (HdRenderIndex *index, HdRprimCollection const &collection) override
	Create a renderpass.
HdInstancer *	CreateInstancer (HdSceneDelegate *delegate, SdfPath const &id) override
	Create an instancer.
void	DestroyInstancer (HdInstancer *instancer) override
	Destroy an instancer created with CreateInstancer.
HdRprim *	CreateRprim (TfToken const &typeId, SdfPath const &rprimId) override
	Create a hydra Rprim, representing scene geometry.
void	DestroyRprim (HdRprim *rPrim) override
	Destroy an Rprim created with CreateRprim.
HdSprim *	CreateSprim (TfToken const &typeId, SdfPath const &sprimId) override
	Create a hydra Sprim, representing scene or viewport state like cameras or lights.
HdSprim *	CreateFallbackSprim (TfToken const &typeId) override
	Create a hydra Sprim using default values, and with no scene graph binding.
void	DestroySprim (HdSprim *sPrim) override
	Destroy an Sprim created with CreateSprim or CreateFallbackSprim.
HdBprim *	CreateBprim (TfToken const &typeId, SdfPath const &bprimId) override
	Create a hydra Bprim, representing data buffers such as textures.
HdBprim *	CreateFallbackBprim (TfToken const &typeId) override
	Create a hydra Bprim using default values, and with no scene graph binding.
void	DestroyBprim (HdBprim *bPrim) override
	Destroy a Bprim created with CreateBprim or CreateFallbackBprim.
void	CommitResources (HdChangeTracker *tracker) override
	This function is called after new scene data is pulled during prim Sync(), but before any tasks (such as draw tasks) are run, and gives the render delegate a chance to transfer any invalidated resources to the rendering kernel.
TfToken	GetMaterialBindingPurpose () const override
	This function tells the scene which material variant to reference.
HdAovDescriptor	GetDefaultAovDescriptor (TfToken const &name) const override
	This function returns the default AOV descriptor for a given named AOV.
VtDictionary	GetRenderStats () const override
	This function allows the renderer to report back some useful statistics that the application can display to the user.

Detailed Description

Render delegates provide renderer-specific functionality to the render index, the main hydra state management structure.

The render index uses the render delegate to create and delete scene primitives, which include geometry and also non-drawable objects. The render delegate is also responsible for creating renderpasses, which know how to draw this renderer's scene primitives.

Primitives in Hydra are split into Rprims (drawables), Sprims (state objects like cameras and materials), and Bprims (buffer objects like textures). The minimum set of primitives a renderer needs to support is one Rprim (so the scene's not empty) and the "camera" Sprim, which is required by HdxRenderTask, the task implementing basic hydra drawing.

A render delegate can report which prim types it supports via GetSupportedRprimTypes() (and Sprim, Bprim), and well-behaved applications won't call CreateRprim() (Sprim, Bprim) for prim types that aren't supported. The core hydra prim types are "mesh", "basisCurves", and "points", but a custom render delegate and a custom scene delegate could add support for other prims such as implicit surfaces or volumes.

HdEmbree Rprims create embree geometry objects in the render delegate's top-level embree scene; and HdEmbree's render pass draws by casting rays into the top-level scene. The renderpass writes to renderbuffers, which are then composited into the GL framebuffer.

The render delegate also has a hook for the main hydra execution algorithm (HdEngine::Execute()): between HdRenderIndex::SyncAll(), which pulls new scene data, and execution of tasks, the engine calls back to CommitResources(). This can be used to commit GPU buffers, or as a place to schedule a final BVH build (though Embree doesn't currenlty use it). Importantly, no scene updates are processed after CommitResources().

Definition at line 84 of file renderDelegate.h.

Constructor & Destructor Documentation

HdEmbreeRenderDelegate() [1/2]

HdEmbreeRenderDelegate

(

)

Render delegate constructor.

This method creates the RTC device and scene, and links embree error handling to hydra error handling.

HdEmbreeRenderDelegate() [2/2]

HdEmbreeRenderDelegate

(

HdRenderSettingsMap const &

settingsMap

)

Render delegate constructor.

This method creates the RTC device and scene, and links embree error ahndling to hydra error handling. It also populates initial render settings.

~HdEmbreeRenderDelegate()

~HdEmbreeRenderDelegate ( )

override

Render delegate destructor.

This method destroys the RTC device and scene.

Member Function Documentation

CommitResources()

void CommitResources ( HdChangeTracker *  tracker )

override

This function is called after new scene data is pulled during prim Sync(), but before any tasks (such as draw tasks) are run, and gives the render delegate a chance to transfer any invalidated resources to the rendering kernel.

Parameters

tracker

The change tracker passed to prim Sync().

CreateBprim()

HdBprim * CreateBprim ( TfToken const &  typeId, SdfPath const &  bprimId  )

override

Create a hydra Bprim, representing data buffers such as textures.

Parameters

typeId	The bprim type to create. This must be one of the types from GetSupportedBprimTypes().
bprimId	The scene graph ID of this bprim, used when pulling data from a scene delegate.

Returns

An embree bprim object.

CreateFallbackBprim()

HdBprim * CreateFallbackBprim ( TfToken const &  typeId )

override

Create a hydra Bprim using default values, and with no scene graph binding.

Parameters

typeId

The bprim type to create. This must be one of the types from GetSupportedBprimTypes().

Returns

An embree fallback bprim object.

CreateFallbackSprim()

HdSprim * CreateFallbackSprim ( TfToken const &  typeId )

override

Create a hydra Sprim using default values, and with no scene graph binding.

Parameters

typeId

The sprim type to create. This must be one of the types from GetSupportedSprimTypes().

Returns

An embree fallback sprim object.

CreateInstancer()

HdInstancer * CreateInstancer ( HdSceneDelegate *  delegate, SdfPath const &  id  )

override

Create an instancer.

Hydra instancers store data needed for an instanced object to draw itself multiple times.

Parameters

delegate	The scene delegate providing data for this instancer.
id	The scene graph ID of this instancer, used when pulling data from a scene delegate.

Returns

An embree instancer object.

CreateRenderPass()

HdRenderPassSharedPtr CreateRenderPass ( HdRenderIndex *  index, HdRprimCollection const &  collection  )

override

Create a renderpass.

Hydra renderpasses are responsible for drawing a subset of the scene (specified by the "collection" parameter) to the current framebuffer. This class creates objects of type HdEmbreeRenderPass, which draw using embree's raycasting API.

Parameters

index	The render index this renderpass will be bound to.
collection	A specifier for which parts of the scene should be drawn.

Returns

An embree renderpass object.

CreateRprim()

HdRprim * CreateRprim ( TfToken const &  typeId, SdfPath const &  rprimId  )

override

Create a hydra Rprim, representing scene geometry.

This class creates embree-specialized geometry containers like HdEmbreeMesh which map scene data to embree scene graph objects.

Parameters

typeId	The rprim type to create. This must be one of the types from GetSupportedRprimTypes().
rprimId	The scene graph ID of this rprim, used when pulling data from a scene delegate.

Returns

An embree rprim object.

CreateSprim()

HdSprim * CreateSprim ( TfToken const &  typeId, SdfPath const &  sprimId  )

override

Create a hydra Sprim, representing scene or viewport state like cameras or lights.

Parameters

typeId	The sprim type to create. This must be one of the types from GetSupportedSprimTypes().
sprimId	The scene graph ID of this sprim, used when pulling data from a scene delegate.

Returns

An embree sprim object.

DestroyBprim()

void DestroyBprim ( HdBprim *  bPrim )

override

Destroy a Bprim created with CreateBprim or CreateFallbackBprim.

Parameters

bPrim

The bprim to be destroyed.

DestroyInstancer()

void DestroyInstancer ( HdInstancer *  instancer )

override

Destroy an instancer created with CreateInstancer.

Parameters

instancer

The instancer to be destroyed.

DestroyRprim()

void DestroyRprim ( HdRprim *  rPrim )

override

Destroy an Rprim created with CreateRprim.

Parameters

rPrim

The rprim to be destroyed.

DestroySprim()

void DestroySprim ( HdSprim *  sPrim )

override

Destroy an Sprim created with CreateSprim or CreateFallbackSprim.

Parameters

sPrim

The sprim to be destroyed.

GetDefaultAovDescriptor()

HdAovDescriptor GetDefaultAovDescriptor ( TfToken const &  name ) const

override

This function returns the default AOV descriptor for a given named AOV.

This mechanism lets the renderer decide things like what format a given AOV will be written as.

Parameters

name	The name of the AOV whose descriptor we want.

Returns

A descriptor specifying things like what format the AOV output buffer should be.

GetMaterialBindingPurpose()

TfToken GetMaterialBindingPurpose ( ) const

inlineoverride

This function tells the scene which material variant to reference.

Embree doesn't currently use materials but raytraced backends generally specify "full".

Returns

A token specifying which material variant this renderer prefers.

Definition at line 224 of file renderDelegate.h.

GetRenderParam()

HdRenderParam * GetRenderParam ( ) const

override

Return this delegate's render param.

Returns

A shared instance of HdEmbreeRenderParam.

GetRenderSettingDescriptors()

HdRenderSettingDescriptorList GetRenderSettingDescriptors ( ) const

override

Returns a list of user-configurable render settings.

This is a reflection API for the render settings dictionary; it need not be exhaustive, but can be used for populating application settings UI.

GetRenderStats()

VtDictionary GetRenderStats ( ) const

override

This function allows the renderer to report back some useful statistics that the application can display to the user.

GetResourceRegistry()

HdResourceRegistrySharedPtr GetResourceRegistry ( ) const

override

Returns the HdResourceRegistry instance used by this render delegate.

GetSupportedBprimTypes()

const TfTokenVector & GetSupportedBprimTypes ( ) const

override

Return a list of which Bprim types can be created by this class's CreateBprim.

GetSupportedRprimTypes()

const TfTokenVector & GetSupportedRprimTypes ( ) const

override

Return a list of which Rprim types can be created by this class's CreateRprim.

GetSupportedSprimTypes()

const TfTokenVector & GetSupportedSprimTypes ( ) const

override

Return a list of which Sprim types can be created by this class's CreateSprim.

IsPauseSupported()

bool IsPauseSupported ( ) const

override

Return true to indicate that pausing and resuming are supported.

Pause()

bool Pause ( )

override

Pause background rendering threads.

Resume()

bool Resume ( )

override

Resume background rendering threads.

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

• pxr/imaging/hdEmbree/renderDelegate.h