niPrototypePropagatingSceneIndex.h

//
// Copyright 2022 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "Apache License")
// with the following modification; you may not use this file except in
// compliance with the Apache License and the following modification to it:
// Section 6. Trademarks. is deleted and replaced with:
//
// 6. Trademarks. This License does not grant permission to use the trade
//    names, trademarks, service marks, or product names of the Licensor
//    and its affiliates, except as required to comply with Section 4(c) of
//    the License and to reproduce the content of the NOTICE file.
//
// You may obtain a copy of the Apache License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the Apache License with the above modification is
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the Apache License for the specific
// language governing permissions and limitations under the Apache License.
//
#ifndef PXR_USD_IMAGING_USD_IMAGING_NI_PROTOTYPE_PROPAGATING_SCENE_INDEX_H
#define PXR_USD_IMAGING_USD_IMAGING_NI_PROTOTYPE_PROPAGATING_SCENE_INDEX_H
 
#include "pxr/usdImaging/usdImaging/api.h"
 
#include "pxr/imaging/hd/dataSourceHash.h"
#include "pxr/imaging/hd/filteringSceneIndex.h"
 
PXR_NAMESPACE_OPEN_SCOPE
 
TF_DECLARE_REF_PTRS(HdMergingSceneIndex);
 
TF_DECLARE_REF_PTRS(UsdImagingNiPrototypePropagatingSceneIndex);
 
class UsdImagingNiPrototypePropagatingSceneIndex final
                                : public HdFilteringSceneIndexBase
{
public:
    using SceneIndexAppendCallback =
        std::function<
            HdSceneIndexBaseRefPtr(const HdSceneIndexBaseRefPtr &inputScene)>;
 
    // instanceDataSourceNames are the names of the data sources of a native
    // instance prim that need to have the same values for the instances to
    // be aggregated. A copy of these data sources is bundled into the
    // prim data source for the binding scope.
    //
    // When propagating a prototype by inserting the scene index isolating
    // that prototype into the merging scene index implementing this scene
    // index, we also call sceneIndexAppendCallback.
    //
    // The use case is for the UsdImagingDrawModeSceneIndex.
    //
    USDIMAGING_API
    static UsdImagingNiPrototypePropagatingSceneIndexRefPtr New(
        HdSceneIndexBaseRefPtr const &inputSceneIndex,
        const TfTokenVector &instanceDataSourceNames,
        const SceneIndexAppendCallback &sceneIndexAppendCallback);
 
    USDIMAGING_API
    ~UsdImagingNiPrototypePropagatingSceneIndex() override;
 
    USDIMAGING_API
    HdSceneIndexPrim GetPrim(const SdfPath &primPath) const override;
 
    USDIMAGING_API
    SdfPathVector GetChildPrimPaths(const SdfPath &primPath) const override;
 
    USDIMAGING_API
    std::vector<HdSceneIndexBaseRefPtr> GetInputScenes() const override;
 
private:
    class _SceneIndexCache;
    using _SceneIndexCacheSharedPtr =
        std::shared_ptr<_SceneIndexCache>;
 
    class _MergingSceneIndexEntry;
    using _MergingSceneIndexEntryUniquePtr =
        std::unique_ptr<_MergingSceneIndexEntry>;
 
    friend class _InstanceAggregationSceneIndexObserver;
    class _InstanceAggregationSceneIndexObserver : public HdSceneIndexObserver
    {
    public:
        _InstanceAggregationSceneIndexObserver(
            UsdImagingNiPrototypePropagatingSceneIndex * owner);
 
        void PrimsAdded(
            const HdSceneIndexBase &sender,
            const AddedPrimEntries &entries) override;
        void PrimsDirtied(
            const HdSceneIndexBase &sender,
            const DirtiedPrimEntries &entries) override;
        void PrimsRemoved(
            const HdSceneIndexBase &sender,
            const RemovedPrimEntries &entries) override;
        void PrimsRenamed(
            const HdSceneIndexBase &sender,
            const RenamedPrimEntries &entries) override;
 
    private:
        UsdImagingNiPrototypePropagatingSceneIndex * const _owner;
    };
 
    friend class _MergingSceneIndexObserver;
    class _MergingSceneIndexObserver : public HdSceneIndexObserver
    {
    public:
        _MergingSceneIndexObserver(
            UsdImagingNiPrototypePropagatingSceneIndex * owner);
 
        void PrimsAdded(
            const HdSceneIndexBase &sender,
            const AddedPrimEntries &entries) override;
        void PrimsDirtied(
            const HdSceneIndexBase &sender,
            const DirtiedPrimEntries &entries) override;
        void PrimsRemoved(
            const HdSceneIndexBase &sender,
            const RemovedPrimEntries &entries) override;
        void PrimsRenamed(
            const HdSceneIndexBase &sender,
            const RenamedPrimEntries &entries) override;
        
    private:
        UsdImagingNiPrototypePropagatingSceneIndex * const _owner;
    };
 
    // Use prototypeName to instantiate for "scene root".
    static UsdImagingNiPrototypePropagatingSceneIndexRefPtr _New(
        const TfToken &prototypeName,
        HdContainerDataSourceHandle const &prototypeRootOverlayDs,
        _SceneIndexCacheSharedPtr const &cache);
 
    UsdImagingNiPrototypePropagatingSceneIndex(
        const TfToken &prototypeName,
        HdContainerDataSourceHandle const &prototypeRootOverlayDs,
        _SceneIndexCacheSharedPtr const &cache);
 
    void _Populate(HdSceneIndexBaseRefPtr const &instanceAggregationSceneIndex);
    void _AddPrim(const SdfPath &primPath);
    void _RemovePrim(const SdfPath &primPath);
 
    const TfToken _prototypeName;
    const HdDataSourceHashType _prototypeRootOverlayDsHash;
    _SceneIndexCacheSharedPtr const _cache;
 
    HdMergingSceneIndexRefPtr _mergingSceneIndex;
 
    std::map<SdfPath, _MergingSceneIndexEntryUniquePtr>
        _instancersToMergingSceneIndexEntry;
 
    HdSceneIndexBaseRefPtr _instanceAggregationSceneIndex;
 
    _InstanceAggregationSceneIndexObserver
        _instanceAggregationSceneIndexObserver;
    _MergingSceneIndexObserver _mergingSceneIndexObserver;
};
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif