HdSceneIndexPlugin Class Reference

A scene index plugin bundles one or more (typically filtering) scene indices together and enables their runtime discovery and participation in the scene index graph construction process. More...

#include <sceneIndexPlugin.h>

Inheritance diagram for HdSceneIndexPlugin:

Public Member Functions
HD_API HdSceneIndexBaseRefPtr	AppendSceneIndex (const std::string &renderInstanceId, const HdSceneIndexBaseRefPtr &inputScene, const HdContainerDataSourceHandle &inputArgs)
HD_API bool	IsEnabled (const HdContainerDataSourceHandle &inputArgs) const
	Returns true if the plugin is enabled, in the sense that it should be consulted for its contribution to the scene index chain via AppendSceneIndex.

Protected Member Functions
virtual HD_API HdSceneIndexBaseRefPtr	_AppendSceneIndex (const HdSceneIndexBaseRefPtr &inputScene, const HdContainerDataSourceHandle &inputArgs)
	Subclasses implement this to instantiate one or more scene indicies which take the provided scene as input.
virtual HD_API HdSceneIndexBaseRefPtr	_AppendSceneIndex (const std::string &renderInstanceId, const HdSceneIndexBaseRefPtr &inputScene, const HdContainerDataSourceHandle &inputArgs)
	Subclasses implement this to instantiate one or more scene indicies which take the provided scene as input.
virtual HD_API bool	_IsEnabled (const HdContainerDataSourceHandle &inputArgs) const
	Subclasses implement this to indicate whether the plugin is enabled.

Detailed Description

A scene index plugin bundles one or more (typically filtering) scene indices together and enables their runtime discovery and participation in the scene index graph construction process.

Scene index plugins leverage the Plug system and are required to have a corresponding entry in the plugInfo.json file in the library directory they are housed in. They are managed by the HdSceneIndexPluginRegistry.

The JSON entry for a scene index plugin should have the following structure:

"MySceneIndexPlugin": {
    "bases": ["HdSceneIndexPlugin"],
 
    # Mandatory fields for "hydra plugins" due to HfPluginRegistry.
    "displayName": "My Awesome Plugin", # Unused currently.
    "priority": 0, # Not relevant for scene index plugins.
 
    # Filtering fields that specify which renderers and apps the plugin
    # is relevant for. The empty string "" indicates "all".
    #
    "loadWithRenderer": ["rendererA", "rendererB"], # Mandatory.
    "loadWithApps": ["appA", "appB"], # Optional, defaults to "" (all).
 
    # Fields that specify tags and tag-based ordering constraints for the
    # plugin. These fields provide an alternative and improvement to the
    # insertion phase/order based constraints of the C++ registration API.
    # These constraints are considered when the ordering policy used by the 
    # HdSceneIndexPluginRegistry is "Hybrid" or "JsonMetadataOnly".
 
    "tags": ["tagA", "tagB"], # Optional. The plugin typename serves as an
                              # implicit tag.
    "ordering": { # Optional.
 
       # Tags or plugin typenames that this plugin should be ordered after.
        "after": ["PluginTypeName1", "Tag3"],
 
        # Tags or plugin typenames that this plugin should be ordered before.
        "before": ["PluginTypeName2", "Tag4"],
 
        # The tags above partition the plugins into three groups (indicated
        # by [] below):
        # [afterTags] -> [... -> "MySceneIndexPlugin" -> ...] -> [beforeTags]
        # The insertion position specifies the ordering of this plugin 
        # within the middle group of plugins, with the options:
        # - "firstAfter": insert as early as possible, after the afterTags.
        # - "lastBefore": insert as late as possible, before the beforeTags.
        # - "doesNotMatter": insert in any position within the middle group.
        # The default is "doesNotMatter".
        "position": "firstAfter"
    }
}

See also

HdSceneIndexPluginRegistry

HdSceneIndexPluginRegistry::PluginOrderingPolicy

HdSceneIndexPluginRegistry::RegisterSceneIndexForRenderer

Definition at line 76 of file sceneIndexPlugin.h.

Member Function Documentation

_AppendSceneIndex() [1/2]

virtual HD_API HdSceneIndexBaseRefPtr _AppendSceneIndex ( const HdSceneIndexBaseRefPtr &  inputScene, const HdContainerDataSourceHandle &  inputArgs  )

protectedvirtual

Subclasses implement this to instantiate one or more scene indicies which take the provided scene as input.

The return value should be the final scene created – or the inputScene itself if nothing is created.

Reimplemented in HdGpSceneIndexPlugin, HdPrman_DependencySceneIndexPlugin, HdPrman_MatFiltSceneIndexPlugin, HdPrman_PortalLightResolvingSceneIndexPlugin, HdPrman_TetMeshConversionSceneIndexPlugin, and HdsiDebuggingSceneIndexPlugin.

_AppendSceneIndex() [2/2]

virtual HD_API HdSceneIndexBaseRefPtr _AppendSceneIndex ( const std::string &  renderInstanceId, const HdSceneIndexBaseRefPtr &  inputScene, const HdContainerDataSourceHandle &  inputArgs  )

protectedvirtual

Subclasses implement this to instantiate one or more scene indicies which take the provided scene as input.

The return value should be the final scene created – or the inputScene itself if nothing is created.

Callers can override this method if they want to get the render instance ID in addition to the input scene and arguments. Callers should only override one of the two _AppendSceneIndex overrides: if both are overridden, only this override will be called.

_IsEnabled()

virtual HD_API bool _IsEnabled ( const HdContainerDataSourceHandle &  inputArgs ) const

protectedvirtual

Subclasses implement this to indicate whether the plugin is enabled.

This is preferable to using env guards to gate registration and scene index instatiation in _AppendSceneIndex.

Base implementation returns true.

Reimplemented in HdGpSceneIndexPlugin, and HdsiDebuggingSceneIndexPlugin.

IsEnabled()

HD_API bool IsEnabled

(

const HdContainerDataSourceHandle &

inputArgs

)

const

Returns true if the plugin is enabled, in the sense that it should be consulted for its contribution to the scene index chain via AppendSceneIndex.

Current implementation simply delegates to _IsEnabled; this may change in the future to first consult inputArgs (e.g. to check a data source that provides the plugin IDs to disable) before calling _IsEnabled.

See also

HdSceneIndexPluginRegistry::AppendSceneIndex.

---

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

• pxr/imaging/hd/sceneIndexPlugin.h