/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2014 Robert Osfield
 * Copyright (C) 2012 David Callu
 * std::vector specialization : Pawel Ksiezopolski
 *
 * This library is open source and may be redistributed and/or modified under
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * OpenSceneGraph Public License for more details.
*/

#ifndef OSG_BUFFERTEMPLATE
#define OSG_BUFFERTEMPLATE 1

#include <osg/BufferObject>
#include <vector>

namespace osg
{

/** Template buffer class to be used with a struct as template parameter.
  * This class is usefull to send C++ structures on the GPU (e.g. for uniform blocks) but be carefull to the alignments rules on the GPU side !
  */
template <typename T>
class BufferTemplate : public BufferData
{
    public:
        BufferTemplate():
            BufferData(),
            _data(T())
        {}

        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
        BufferTemplate(const BufferTemplate<T>& bt,const CopyOp& copyop=CopyOp::SHALLOW_COPY):
            osg::BufferData(bt,copyop),
            _data(bt._data)
        {}

        virtual bool isSameKindAs(const Object* obj) const { return dynamic_cast<const BufferTemplate<T>*>(obj)!=NULL; }
        virtual const char* libraryName() const { return "osg"; }
        virtual const char* className() const { return "BufferTemplate<T>"; }

        virtual Object* cloneType() const { return new BufferTemplate<T>(); }
        virtual Object* clone(const CopyOp& copyop) const { return new BufferTemplate<T>(*this,copyop); }

        virtual const GLvoid*   getDataPointer() const { return &_data; }
        virtual unsigned int    getTotalDataSize() const  { return sizeof(T); }
        
        const T& getData() const { return _data; }
        T&       getData() { return _data; }
        void     setData(const T& data) { _data = data; dirty(); }

    protected:
        virtual ~BufferTemplate() {};

    private:
        T _data;
};

/** BufferTemplate specialization for std::vector
 */
template <typename T>
class BufferTemplate< std::vector<T> > : public BufferData
{
    public:
        BufferTemplate():
            BufferData(),
            _data()
        {}

        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
        BufferTemplate(const BufferTemplate< std::vector<T> >& bt,const CopyOp& copyop=CopyOp::SHALLOW_COPY):
            osg::BufferData(bt,copyop),
            _data(bt._data)
        {}

        virtual bool isSameKindAs(const Object* obj) const { return dynamic_cast<const BufferTemplate< std::vector<T> >*>(obj)!=NULL; }
        virtual const char* libraryName() const { return "osg"; }
        virtual const char* className() const { return "BufferTemplate<std::vector<T> >"; }

        virtual Object* cloneType() const { return new BufferTemplate< std::vector<T> >(); }
        virtual Object* clone(const CopyOp& copyop) const { return new BufferTemplate< std::vector<T> >(*this,copyop); }

        virtual const GLvoid*   getDataPointer() const { return &_data[0]; }
        virtual unsigned int    getTotalDataSize() const  { return _data.size() * sizeof(T); }
        
        const std::vector<T>&   getData() const { return _data; }
        std::vector<T>&         getData() { return _data; }
        void                    setData(const std::vector<T>& data) { _data = data; dirty(); }

    protected:
        virtual ~BufferTemplate() {};

    private:
        std::vector<T> _data;
};

}

#endif