How to call CPP from Fortran

I need to call a DLL coded in C++ from my Fortran. The methods I need to call are object-oriented, and described in .h files. Here is the first 50 or so lines from one of the .h files:

#ifndef BBE_PVTT_BLACK_OIL_FLUID_H

	#define BBE_PVTT_BLACK_OIL_FLUID_H
#include <PVTT/API/Model/Dll.h>

	#include <PVTT/API/Common/PVTTEnum.h>

	#include <PVTT/API/Common/PVTTBlackOilEnum.h>

	#include <PVTT/API/Common/BlackOilImpurities.h>

	#include <PVTT/API/Common/BlackOilComposition.h>
#include <string>
namespace BBE { namespace PVTT { namespace Common {

	  class ErrorReport;

	} } }
namespace BBE { namespace PVTT { namespace Impl { namespace Command {

	  class BlackOilFluidCommand;

	} } } }
namespace BBE { namespace PVTT { namespace Model {
  class BBE_PVTT_API_MODEL_DECL BlackOilFluid

	  {

	  public:

	   

	    BlackOilFluid(const std::string& name="");

	    BlackOilFluid(const BlackOilFluid&);

	    BlackOilFluid& operator=(const BlackOilFluid&);

	    ~BlackOilFluid();
    bool operator==(const BlackOilFluid&) const;

	    bool operator!=(const BlackOilFluid&) const;
    std::string GetName() const;

	    void SetName(const std::string& name);
    // Set properties

	    void SetOilAPI(double OilAPI);  // setting oil API sets oil specific gravity and vice versa

	    void SetOilSpecificGravity(double OilSpecificGravity);

	    void SetGasSpecificGravity(double value, BBE::PVTT::Common::pvtEnumGasSpecGravCondition conditions= BBE::PVTT::Common::pvtCONDITION_STD);

	    void SetSeparatorConditions(double separatorPressure, double separatorTemperature);

	    void SetWaterSpecificGravity(double waterSpecificGravity);

	    void SetWaterSalinity(double weightPercent);

	    void SetImpurities(const BBE::PVTT::Common::BlackOilImpurities& impurities);

	    void SetGasComposition(const BBE::PVTT::Common::BlackOilComposition& composition);

	    void SetGasPpcTpc(double Ppc, double Tpc);

	    void SetStockTankRelativeVolumes( double gas, double oil, double water );

	    void SetDeadOilViscosityCoefficientA( double coeffA );

	    void SetDeadOilViscosityCoefficientB( double coeffB );

	    void SetGasSpecificHeatCapacity( double gasCp );

	    void SetOilSpecificHeatCapacity( double oilCp );

	    void SetWaterSpecificHeatCapacity( double waterCp );

	    void SetGasThermalConductivity( double gasTc );

	    void SetOilThermalConductivity( double oilTc );

	    void SetWaterThermalConductivity( double waterTc );

	    void SetSpecificLatentHeatOfVaporization( double specificLatentHeatOfVaporization );

Ideally, I would like to wind up with Object-oriented Fortran code, where a call to one of the above methods uses standard Fortran 2003 syntax, somethig like

      call fluid%SetOilApi(35.0d0)
      call fluid%SetSeparatorConditions(1d6,320d0)

To make this happen, I realize I need to create a Fortran INTERFACE definition to describe all the methods I need to call. But I have no real idea what this would look like ... or even if it is possible at all. Any pointers and/or advice to get me started, please?

Qolin