mapnik/agg/include/agg_span_allocator.h
2006-01-31 23:09:52 +00:00

74 lines
2.4 KiB
C++

//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.4
// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
//
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//
//----------------------------------------------------------------------------
// Contact: mcseem@antigrain.com
// mcseemagg@yahoo.com
// http://www.antigrain.com
//----------------------------------------------------------------------------
#ifndef AGG_SPAN_ALLOCATOR_INCLUDED
#define AGG_SPAN_ALLOCATOR_INCLUDED
#include "agg_basics.h"
namespace agg
{
//----------------------------------------------------------span_allocator
template<class ColorT> class span_allocator
{
public:
typedef ColorT color_type;
//--------------------------------------------------------------------
~span_allocator()
{
delete [] m_span;
}
//--------------------------------------------------------------------
span_allocator() :
m_max_span_len(0),
m_span(0)
{
}
//--------------------------------------------------------------------
AGG_INLINE color_type* allocate(unsigned span_len)
{
if(span_len > m_max_span_len)
{
// To reduce the number of reallocs we align the
// span_len to 256 color elements.
// Well, I just like this number and it looks reasonable.
//-----------------------
delete [] m_span;
span_len = ((span_len + 255) >> 8) << 8;
m_span = new color_type[m_max_span_len = span_len];
}
return m_span;
}
AGG_INLINE color_type* span() { return m_span; }
AGG_INLINE unsigned max_span_len() const { return m_max_span_len; }
private:
//--------------------------------------------------------------------
span_allocator(const span_allocator<ColorT>&);
const span_allocator<ColorT>& operator = (const span_allocator<ColorT>&);
unsigned m_max_span_len;
color_type* m_span;
};
}
#endif