extCompGpuComputation.h

//
// Copyright 2017 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_ST_EXT_COMP_GPU_COMPUTATION_H
#define PXR_IMAGING_HD_ST_EXT_COMP_GPU_COMPUTATION_H

#include "pxr/pxr.h"
#include "pxr/imaging/hdSt/api.h"
#include "pxr/imaging/hdSt/extCompGpuComputationResource.h"
#include "pxr/imaging/hdSt/resourceBinder.h"
#include "pxr/imaging/hd/bufferSource.h"
#include "pxr/imaging/hd/computation.h"
#include "pxr/imaging/hd/types.h"
#include "pxr/usd/sdf/path.h"
#include "pxr/base/tf/token.h"
#include "pxr/base/vt/value.h"

#include <memory>
#include <vector>

PXR_NAMESPACE_OPEN_SCOPE

class HdSceneDelegate;
class HdExtComputation;
using HdStGLSLProgramSharedPtr= std::shared_ptr<class HdStGLSLProgram>;
using HdExtComputationPrimvarDescriptorVector =
    std::vector<struct HdExtComputationPrimvarDescriptor>;

using HdStExtCompGpuComputationSharedPtr = 
    std::shared_ptr<class HdStExtCompGpuComputation>;


class HdStExtCompGpuComputation final : public HdComputation {
public:
    HdStExtCompGpuComputation(
            SdfPath const &id,
            HdStExtCompGpuComputationResourceSharedPtr const &resource,
            HdExtComputationPrimvarDescriptorVector const &compPrimvars,
            int dispatchCount,
            int elementCount);

    HDST_API
    static HdStExtCompGpuComputationSharedPtr
    CreateGpuComputation(
        HdSceneDelegate *sceneDelegate,
        HdExtComputation const *sourceComp,
        HdExtComputationPrimvarDescriptorVector const &compPrimvars);

    HDST_API
    virtual ~HdStExtCompGpuComputation() = default;

    HDST_API
    virtual void GetBufferSpecs(HdBufferSpecVector *specs) const override;

    HDST_API
    virtual void Execute(HdBufferArrayRangeSharedPtr const &range,
                         HdResourceRegistry *resourceRegistry) override;

    HDST_API
    int GetDispatchCount() const;

    HDST_API
    virtual int GetNumOutputElements() const override;
    
    HDST_API
    virtual HdStExtCompGpuComputationResourceSharedPtr const &
    GetResource() const;

private:
    SdfPath                                      _id;
    HdStExtCompGpuComputationResourceSharedPtr   _resource;
    HdExtComputationPrimvarDescriptorVector      _compPrimvars;
    int                                          _dispatchCount;
    int                                          _elementCount;

    HdStExtCompGpuComputation()                                        = delete;
    HdStExtCompGpuComputation(const HdStExtCompGpuComputation &)       = delete;
    HdStExtCompGpuComputation &operator = (const HdStExtCompGpuComputation &)
                                                                       = delete;
};


HDST_API
void HdSt_GetExtComputationPrimvarsComputations(
    const SdfPath &id,
    HdSceneDelegate *sceneDelegate,
    HdExtComputationPrimvarDescriptorVector const& allCompPrimvars,
    HdDirtyBits dirtyBits,
    HdBufferSourceSharedPtrVector *sources,
    HdBufferSourceSharedPtrVector *reserveOnlySources,
    HdBufferSourceSharedPtrVector *separateComputationSources,
    HdStComputationSharedPtrVector *computations);

PXR_NAMESPACE_CLOSE_SCOPE

#endif // PXR_IMAGING_HD_ST_EXT_COMP_GPU_COMPUTATION_H