SoAutoMap.h

/*=======================================================================
** VSG_COPYRIGHT_TAG
**=======================================================================*/
/*=======================================================================
** Author      : David Beilloin (Aug 2013)
**=======================================================================*/
 
#if !defined(_SO_AUTO_MAP_H_)
#define _SO_AUTO_MAP_H_
 
#include <Inventor/devices/SoLocalCpuBufferObject.h>
 
template<typename T>
class SoAutoMap
{
public:
 
  SoAutoMap(SoBufferObject* bufferObject, SoBufferObject::AccessMode accessMode)
    :m_bufferObject(bufferObject)
  {
    m_bufferObject->map(&m_cpuBufferObject,accessMode);
    m_pointer = static_cast<T*>(m_cpuBufferObject.map(accessMode));
    m_arraySize = bufferObject->getSize()/sizeof(T);
  }
 
  ~SoAutoMap()
  {
    m_cpuBufferObject.unmap();
    m_bufferObject->unmap(&m_cpuBufferObject);
  }
 
  T& operator[](const size_t i)
  {
    assert(i<m_arraySize);
    return (m_pointer[i]);
  }
 
  const T& operator[](const size_t i) const
  {
    assert(i<m_arraySize);
    return (m_pointer[i]);
  }
 
  size_t getSize() const
  { return m_arraySize; }
 
private:
  // private default constructor to avoid copy by reference
  SoAutoMap(){}
 
  // cpu bufferobject to keep track of the current mapping
  SoLocalCpuBufferObject m_cpuBufferObject;
 
  // keep track of the source mapped buffer object
  SoBufferObject* m_bufferObject;
 
  // keep track of the pointer target of the mapping
  T* m_pointer;
  
  // keep track of the buffer size in number of element
  size_t m_arraySize;
};
 
#endif // _SO_AUTO_MAP_H_