vertexAdjacency.h

//
// Copyright 2016 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_IMAGING_HD_VERTEX_ADJACENCY_H
#define PXR_IMAGING_HD_VERTEX_ADJACENCY_H

#include "pxr/pxr.h"
#include "pxr/imaging/hd/api.h"
#include "pxr/imaging/hd/version.h"
#include "pxr/imaging/hd/bufferArrayRange.h"
#include "pxr/imaging/hd/bufferSource.h"
#include "pxr/imaging/hd/computation.h"

#include "pxr/base/vt/array.h"

#include <memory>

PXR_NAMESPACE_OPEN_SCOPE


using Hd_VertexAdjacencySharedPtr = 
    std::shared_ptr<class Hd_VertexAdjacency>;
using Hd_AdjacencyBuilderComputationSharedPtr = 
    std::shared_ptr<class Hd_AdjacencyBuilderComputation>;
using Hd_AdjacencyBuilderComputationPtr = 
    std::weak_ptr<class Hd_AdjacencyBuilderComputation>;

class HdMeshTopology;

class Hd_VertexAdjacency final {
public:
    HD_API
    Hd_VertexAdjacency();

    HD_API
    ~Hd_VertexAdjacency();

    HD_API
    bool BuildAdjacencyTable(HdMeshTopology const *topology);

    HD_API
    HdBufferSourceSharedPtr GetSharedAdjacencyBuilderComputation(
        HdMeshTopology const *topology);

    void SetAdjacencyRange(HdBufferArrayRangeSharedPtr const &range) {
        _adjacencyRange = range;
    }

    HdBufferArrayRangeSharedPtr const &GetAdjacencyRange() const {
        return _adjacencyRange;
    }

    int GetNumPoints() const {
        return _numPoints;
    }

    VtIntArray const &GetAdjacencyTable() const {
        return _adjacencyTable;
    }

private:
    int _numPoints;
    VtIntArray _adjacencyTable;

    // adjacency buffer range
    HdBufferArrayRangeSharedPtr _adjacencyRange;

    // weak ptr of adjacency builder used for dependent computations
    Hd_AdjacencyBuilderComputationPtr _sharedAdjacencyBuilder;
};

class Hd_AdjacencyBuilderComputation : public HdNullBufferSource {
public:
    HD_API
    Hd_AdjacencyBuilderComputation(Hd_VertexAdjacency *adjacency,
                                   HdMeshTopology const *topology);
    HD_API
    virtual bool Resolve() override;

protected:
    HD_API
    virtual bool _CheckValid() const override;

private:
    Hd_VertexAdjacency *_adjacency;
    HdMeshTopology const *_topology;
};

class Hd_AdjacencyBufferSource : public HdComputedBufferSource {
public:
    HD_API
    Hd_AdjacencyBufferSource(
        Hd_VertexAdjacency const *adjacency,
        HdBufferSourceSharedPtr const &adjacencyBuilder);

    // overrides
    HD_API
    virtual void GetBufferSpecs(HdBufferSpecVector *specs) const override;
    HD_API
    virtual bool Resolve() override;

protected:
    HD_API
    virtual bool _CheckValid() const override;

private:
    Hd_VertexAdjacency const *_adjacency;
    HdBufferSourceSharedPtr const _adjacencyBuilder;
};


PXR_NAMESPACE_CLOSE_SCOPE

#endif  // PXR_IMAGING_HD_VERTEX_ADJACENCY_H