shaderGenerator.h

//
// Copyright 2020 Pixar
//
// Licensed under the terms set forth in the LICENSE.txt file available at
// https://openusd.org/license.
//
 
#ifndef PXR_IMAGING_HGI_SHADERGENERATOR_H
#define PXR_IMAGING_HGI_SHADERGENERATOR_H
 
#include "pxr/pxr.h"
#include "pxr/imaging/hgi/api.h"
#include "pxr/imaging/hgi/enums.h"
 
#include <iosfwd>
#include <string>
 
PXR_NAMESPACE_OPEN_SCOPE
 
struct HgiShaderFunctionDesc;
 
class HgiShaderGenerator
{
public:
    HGI_API
    virtual ~HgiShaderGenerator();
 
    // Execute shader generation.
    HGI_API
    void Execute();
 
    // Return generated shader source.
    HGI_API
    const char *GetGeneratedShaderCode() const;
 
protected:
    HGI_API
    explicit HgiShaderGenerator(const HgiShaderFunctionDesc &descriptor);
 
    HGI_API
    virtual void _Execute(std::ostream &ss) = 0;
 
    HGI_API
    const char *_GetShaderCodeDeclarations() const;
 
    HGI_API
    const char *_GetShaderCode() const;
 
    HGI_API
    HgiShaderStage _GetShaderStage() const;
 
private:
    const HgiShaderFunctionDesc &_descriptor;
 
    // This is used if the descriptor does not specify a string
    // to be used as the destination for generated output.
    std::string _localGeneratedShaderCode;
 
    HgiShaderGenerator() = delete;
    HgiShaderGenerator & operator=(const HgiShaderGenerator&) = delete;
    HgiShaderGenerator(const HgiShaderGenerator&) = delete;
};
 
PXR_NAMESPACE_CLOSE_SCOPE
 
#endif