requestImpl.h

//
// Copyright 2025 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/license.
//
#ifndef PXR_EXEC_EXEC_REQUEST_IMPL_H
#define PXR_EXEC_EXEC_REQUEST_IMPL_H
 
#include "pxr/pxr.h"
 
#include "pxr/exec/exec/api.h"
#include "pxr/exec/exec/request.h"
#include "pxr/exec/exec/valueOverride.h"
 
#include "pxr/base/tf/bits.h"
#include "pxr/base/tf/pxrTslRobinMap/robin_map.h"
#include "pxr/exec/ef/timeInterval.h"
#include "pxr/exec/vdf/maskedOutput.h"
#include "pxr/exec/vdf/types.h"
 
#include <memory>
#include <vector>
 
PXR_NAMESPACE_OPEN_SCOPE
 
class EfLeafNode;
class EfTime;
struct Exec_AttributeValueInvalidationResult;
class Exec_CacheView;
struct Exec_DisconnectedInputsInvalidationResult;
struct Exec_MetadataInvalidationResult;
class Exec_TimeChangeInvalidationResult;
class Exec_ValueExtractor;
class ExecSystem;
class ExecValueKey;
template <typename> class TfSpan;
class VdfRequest;
class VdfSchedule;
 
class Exec_RequestImpl
{
public:
    void DidInvalidateComputedValues(
        const Exec_AttributeValueInvalidationResult &invalidationResult);
 
    void DidInvalidateComputedValues(
        const Exec_MetadataInvalidationResult &invalidationResult);
 
    void DidInvalidateComputedValues(
        const Exec_DisconnectedInputsInvalidationResult &invalidationResult);
 
    void DidInvalidateUnknownValues();
 
    void DidChangeTime(
        const Exec_TimeChangeInvalidationResult &invalidationResult);
 
    void Expire();
 
protected:
    EXEC_API
    Exec_RequestImpl(
        ExecSystem *system,
        ExecRequestComputedValueInvalidationCallback &&valueCallback,
        ExecRequestTimeChangeInvalidationCallback &&timeCallback);
 
    Exec_RequestImpl(const Exec_RequestImpl&) = delete;
    Exec_RequestImpl& operator=(const Exec_RequestImpl&) = delete;
 
    EXEC_API
    ~Exec_RequestImpl();
 
    EXEC_API
    void _Compile(TfSpan<const ExecValueKey> valueKeys);
 
    EXEC_API
    void _Schedule();
 
    EXEC_API
    Exec_CacheView _Compute();
 
    EXEC_API
    Exec_CacheView _ComputeWithOverrides(
        ExecValueOverrideVector &&valueOverrides);
 
    EXEC_API
    bool _RequiresCompilation() const;
 
    EXEC_API
    void _ExpireIndices(const ExecRequestIndexSet &expired);
 
    EXEC_API
    void _Discard();
 
private:
    // Ensures the _leafNodeToIndex map is up-to-date.
    void _BuildLeafNodeToIndexMap(
        TfSpan<const ExecValueKey> valueKeys,
        const std::vector<const EfLeafNode*> &leafNodes);
 
    // Turns invalid leaf nodes into a set of requested - and not previously
    // invalidated - indices.
    // 
    void _InvalidateLeafOutputs(
        bool isNewlyInvalidInterval,
        TfSpan<const VdfNode *const> leafNodes,
        ExecRequestIndexSet *invalidIndices);
 
    // Resets the schedule if any there are any topological network edits to 
    // leaf nodes that are referenced in this request. 
    //
    void _InvalidateScheduleForLeafNodes(
        TfSpan<const VdfNode *const> disconnectedLeafNodes);
 
private:
    // The system that issued this request.
    ExecSystem *_system;
 
    // The compiled leaf output.
    std::vector<VdfMaskedOutput> _leafOutputs;
 
    // Value extractors corresponding to each requested value.
    std::vector<Exec_ValueExtractor> _extractors;
 
    // Maps leaf nodes to their index in the array of valueKeys the request
    // was built with.
    pxr_tsl::robin_map<VdfId, size_t> _leafNodeToIndex;
 
    // The compute request to cache values with.
    std::unique_ptr<VdfRequest> _computeRequest;
 
    // The schedule to cache values with.
    std::unique_ptr<VdfSchedule> _schedule;
 
    // The combined time interval for which invalidation has been sent out.
    EfTimeInterval _lastInvalidatedInterval;
 
    // The combined set of indices for which invalidation has been sent out.
    TfBits _lastInvalidatedIndices;
 
    // The invalidation callback to invoke when computed values change.
    ExecRequestComputedValueInvalidationCallback _valueCallback;
 
    // The invalidation callback to invoke when time changes.
    ExecRequestTimeChangeInvalidationCallback _timeCallback;
};
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif