collectionExpressionEvaluator.h

//
// Copyright 2024 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/license.
//
 
#ifndef PXR_IMAGING_HD_COLLECTION_EXPRESSION_EVALUATOR_H
#define PXR_IMAGING_HD_COLLECTION_EXPRESSION_EVALUATOR_H
 
#include "pxr/pxr.h"
 
#include "pxr/imaging/hd/api.h"
 
#include "pxr/base/tf/declarePtrs.h"
 
#include "pxr/usd/sdf/pathExpressionEval.h"
#include "pxr/usd/sdf/predicateLibrary.h"
 
#include <vector>
 
PXR_NAMESPACE_OPEN_SCOPE
 
class HdSceneIndexBase;
struct HdSceneIndexPrim;
class SdfPathExpression;
 
using SdfPathVector = std::vector<class SdfPath>;
 
TF_DECLARE_WEAK_AND_REF_PTRS(HdSceneIndexBase);
 
using HdCollectionPredicateLibrary =
    SdfPredicateLibrary<const HdSceneIndexPrim &>;
 
class HdCollectionExpressionEvaluator
{
public:
    HdCollectionExpressionEvaluator() = default;
 
    HD_API
    HdCollectionExpressionEvaluator(
        const HdSceneIndexBaseRefPtr &sceneIndex,
        const SdfPathExpression &expr);
 
    HD_API
    HdCollectionExpressionEvaluator(
        const HdSceneIndexBaseRefPtr &sceneIndex,
        const SdfPathExpression &expr,
        const HdCollectionPredicateLibrary &predicateLib);
 
    bool IsEmpty() const {
        return !_sceneIndex || _eval.IsEmpty();
    }
 
    HdSceneIndexBaseRefPtr
    GetSceneIndex() const {
        return _sceneIndex;
    }
 
    HD_API
    SdfPredicateFunctionResult
    Match(const SdfPath &path) const;
 
    HD_API
    void
    PopulateAllMatches(
        const SdfPath &rootPath,
        SdfPathVector * const result) const;
    
    enum MatchKind {
        MatchAll,
        ShallowestMatches,
        ShallowestMatchesAndAllDescendants
    };
 
    HD_API
    void
    PopulateMatches(
        const SdfPath &rootPath,
        MatchKind matchKind,
        SdfPathVector * const result) const;
 
private:
    HdSceneIndexBaseRefPtr _sceneIndex;
 
    using _PrimEvaluator = SdfPathExpressionEval<const HdSceneIndexPrim &>;
    _PrimEvaluator _eval;
};
 
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif // PXR_IMAGING_HD_COLLECTION_EXPRESSION_EVALUATOR_H