haiku/headers/libs/agg/agg_span_interpolator_trans.h

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//----------------------------------------------------------------------------
// 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
//----------------------------------------------------------------------------
//
// Horizontal span interpolator for use with an arbitrary transformer
// The efficiency highly depends on the operations done in the transformer
//
//----------------------------------------------------------------------------
#ifndef AGG_SPAN_INTERPOLATOR_TRANS_INCLUDED
#define AGG_SPAN_INTERPOLATOR_TRANS_INCLUDED
#include "agg_basics.h"
namespace agg
{
//=================================================span_interpolator_trans
template<class Transformer, unsigned SubpixelShift = 8>
class span_interpolator_trans
{
public:
typedef Transformer trans_type;
enum subpixel_scale_e
{
subpixel_shift = SubpixelShift,
subpixel_scale = 1 << subpixel_shift
};
//--------------------------------------------------------------------
span_interpolator_trans() {}
span_interpolator_trans(const trans_type& trans) : m_trans(&trans) {}
span_interpolator_trans(const trans_type& trans,
double x, double y, unsigned) :
m_trans(&trans)
{
begin(x, y, 0);
}
//----------------------------------------------------------------
const trans_type& transformer() const { return *m_trans; }
void transformer(const trans_type& trans) { m_trans = &trans; }
//----------------------------------------------------------------
void begin(double x, double y, unsigned)
{
m_x = x;
m_y = y;
m_trans->transform(&x, &y);
m_ix = iround(x * subpixel_scale);
m_iy = iround(y * subpixel_scale);
}
//----------------------------------------------------------------
void operator++()
{
m_x += 1.0;
double x = m_x;
double y = m_y;
m_trans->transform(&x, &y);
m_ix = iround(x * subpixel_scale);
m_iy = iround(y * subpixel_scale);
}
//----------------------------------------------------------------
void coordinates(int* x, int* y) const
{
*x = m_ix;
*y = m_iy;
}
private:
const trans_type* m_trans;
double m_x;
double m_y;
int m_ix;
int m_iy;
};
}
#endif