OsgProgram.h

// This file is a part of the OpenSurgSim project.
// Copyright 2013-2016, SimQuest Solutions Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef SURGSIM_GRAPHICS_OSGPROGRAM_H
#define SURGSIM_GRAPHICS_OSGPROGRAM_H

#include "SurgSim/Graphics/Program.h"

#include <osg/Program>
#include <osg/StateSet>

#include <string>
#include <memory>
#include <array>

namespace SurgSim
{
namespace Framework
{
class ApplicationData;
}

namespace Graphics
{

SURGSIM_STATIC_REGISTRATION(OsgProgram);

class OsgProgram : public Program
{
public:
    OsgProgram();

    SURGSIM_CLASSNAME(SurgSim::Graphics::OsgProgram);

    bool hasVertexShader() const override;

    void clearVertexShader() override;

    bool loadVertexShader(const std::string& filePath) override;

    void setVertexShaderSource(const std::string& source) override;

    bool getVertexShaderSource(std::string* source) const override;

    bool hasGeometryShader() const override;

    void clearGeometryShader() override;

    bool loadGeometryShader(const std::string& filePath) override;

    void setGeometryShaderSource(const std::string& source) override;

    bool getGeometryShaderSource(std::string* source) const override;

    bool hasFragmentShader() const override;

    void clearFragmentShader() override;

    bool loadFragmentShader(const std::string& filePath) override;

    void setFragmentShaderSource(const std::string& source) override;

    bool getFragmentShaderSource(std::string* source) const override;

    void setGlobalScope(bool val) override;

    bool isGlobalScope() const override;

    osg::ref_ptr<osg::Program> getOsgProgram() const;

    void addToStateSet(osg::StateSet* stateSet);

    void removeFromStateSet(osg::StateSet* stateSet);

private:
    osg::ref_ptr<osg::Program> m_program;

    // Type of shader, internal use only
    enum ShaderType
    {
        SHADER_TYPE_VERTEX = 0,
        SHADER_TYPE_FRAGMENT,
        SHADER_TYPE_GEOMETRY,
        SHADER_TYPE_COUNT
    };

    std::array<osg::ref_ptr<osg::Shader>, SHADER_TYPE_COUNT> m_osgShaders;

    bool hasShader(int shaderType) const;

    void clearShader(int shaderType);

    bool loadShaderSource(const std::string& filePath, int shaderType);

    virtual void setShaderSource(const std::string& source, int shaderType);

    virtual bool getShaderSource(int shaderType, std::string* source) const;

    osg::ref_ptr<osg::Shader> getOrCreateOsgShader(int shaderType);

    bool m_globalScope;

protected:

    bool doLoad(const std::string& filePath) override;

};

std::shared_ptr<SurgSim::Graphics::OsgProgram> loadProgram(const SurgSim::Framework::ApplicationData& data,
        const std::string& name);

std::shared_ptr<SurgSim::Graphics::OsgProgram> loadProgram(const SurgSim::Framework::ApplicationData& data,
        const std::string& vertexShaderName, const std::string& fragmentShaderName);

};  // namespace Graphics

};  // namespace SurgSim

#endif  // SURGSIM_GRAPHICS_OSGPROGRAM_H