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//----------------------------------------------------------------------------
// Anti-Grain Geometry (AGG) - Version 2.5
// A high quality rendering engine for C++
// Copyright (C) 2002-2006 Maxim Shemanarev
// Contact: mcseem@antigrain.com
// mcseemagg@yahoo.com
// http://antigrain.com
//
// AGG is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// AGG 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
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with AGG; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
// MA 02110-1301, USA.
//----------------------------------------------------------------------------
#ifndef AGG_RASTERIZER_SL_CLIP_INCLUDED
#define AGG_RASTERIZER_SL_CLIP_INCLUDED
#include "agg_clip_liang_barsky.h"
namespace agg
{
//--------------------------------------------------------poly_max_coord_e
enum poly_max_coord_e
{
poly_max_coord = (1 << 30) - 1 //----poly_max_coord
};
//------------------------------------------------------------ras_conv_int
struct ras_conv_int
{
typedef int coord_type;
static AGG_INLINE int mul_div(double a, double b, double c)
{
return iround(a * b / c);
}
static int xi(int v) { return v; }
static int yi(int v) { return v; }
static int upscale(double v) { return iround(v * poly_subpixel_scale); }
static int downscale(int v) { return v; }
};
//--------------------------------------------------------ras_conv_int_sat
struct ras_conv_int_sat
{
typedef int coord_type;
static AGG_INLINE int mul_div(double a, double b, double c)
{
return saturation<poly_max_coord>::iround(a * b / c);
}
static int xi(int v) { return v; }
static int yi(int v) { return v; }
static int upscale(double v)
{
return saturation<poly_max_coord>::iround(v * poly_subpixel_scale);
}
static int downscale(int v) { return v; }
};
//---------------------------------------------------------ras_conv_int_3x
struct ras_conv_int_3x
{
typedef int coord_type;
static AGG_INLINE int mul_div(double a, double b, double c)
{
return iround(a * b / c);
}
static int xi(int v) { return v * 3; }
static int yi(int v) { return v; }
static int upscale(double v) { return iround(v * poly_subpixel_scale); }
static int downscale(int v) { return v; }
};
//-----------------------------------------------------------ras_conv_dbl
struct ras_conv_dbl
{
typedef double coord_type;
static AGG_INLINE double mul_div(double a, double b, double c)
{
return a * b / c;
}
static int xi(double v) { return iround(v * poly_subpixel_scale); }
static int yi(double v) { return iround(v * poly_subpixel_scale); }
static double upscale(double v) { return v; }
static double downscale(int v) { return v / double(poly_subpixel_scale); }
};
//--------------------------------------------------------ras_conv_dbl_3x
struct ras_conv_dbl_3x
{
typedef double coord_type;
static AGG_INLINE double mul_div(double a, double b, double c)
{
return a * b / c;
}
static int xi(double v) { return iround(v * poly_subpixel_scale * 3); }
static int yi(double v) { return iround(v * poly_subpixel_scale); }
static double upscale(double v) { return v; }
static double downscale(int v) { return v / double(poly_subpixel_scale); }
};
//------------------------------------------------------rasterizer_sl_clip
template<class Conv> class rasterizer_sl_clip
{
public:
typedef Conv conv_type;
typedef typename Conv::coord_type coord_type;
typedef rect_base<coord_type> rect_type;
//--------------------------------------------------------------------
rasterizer_sl_clip() :
m_clip_box(0,0,0,0),
m_x1(0),
m_y1(0),
m_f1(0),
m_clipping(false)
{}
//--------------------------------------------------------------------
void reset_clipping()
{
m_clipping = false;
}
//--------------------------------------------------------------------
void clip_box(coord_type x1, coord_type y1, coord_type x2, coord_type y2)
{
m_clip_box = rect_type(x1, y1, x2, y2);
m_clip_box.normalize();
m_clipping = true;
}
//--------------------------------------------------------------------
void move_to(coord_type x1, coord_type y1)
{
m_x1 = x1;
m_y1 = y1;
if(m_clipping) m_f1 = clipping_flags(x1, y1, m_clip_box);
}
private:
//------------------------------------------------------------------------
template<class Rasterizer>
AGG_INLINE void line_clip_y(Rasterizer& ras,
coord_type x1, coord_type y1,
coord_type x2, coord_type y2,
unsigned f1, unsigned f2) const
{
f1 &= 10;
f2 &= 10;
if((f1 | f2) == 0)
{
// Fully visible
ras.line(Conv::xi(x1), Conv::yi(y1), Conv::xi(x2), Conv::yi(y2));
}
else
{
if(f1 == f2)
{
// Invisible by Y
return;
}
coord_type tx1 = x1;
coord_type ty1 = y1;
coord_type tx2 = x2;
coord_type ty2 = y2;
if(f1 & 8) // y1 < clip.y1
{
tx1 = x1 + Conv::mul_div(m_clip_box.y1-y1, x2-x1, y2-y1);
ty1 = m_clip_box.y1;
}
if(f1 & 2) // y1 > clip.y2
{
tx1 = x1 + Conv::mul_div(m_clip_box.y2-y1, x2-x1, y2-y1);
ty1 = m_clip_box.y2;
}
if(f2 & 8) // y2 < clip.y1
{
tx2 = x1 + Conv::mul_div(m_clip_box.y1-y1, x2-x1, y2-y1);
ty2 = m_clip_box.y1;
}
if(f2 & 2) // y2 > clip.y2
{
tx2 = x1 + Conv::mul_div(m_clip_box.y2-y1, x2-x1, y2-y1);
ty2 = m_clip_box.y2;
}
ras.line(Conv::xi(tx1), Conv::yi(ty1),
Conv::xi(tx2), Conv::yi(ty2));
}
}
public:
//--------------------------------------------------------------------
template<class Rasterizer>
void line_to(Rasterizer& ras, coord_type x2, coord_type y2)
{
if(m_clipping)
{
unsigned f2 = clipping_flags(x2, y2, m_clip_box);
if((m_f1 & 10) == (f2 & 10) && (m_f1 & 10) != 0)
{
// Invisible by Y
m_x1 = x2;
m_y1 = y2;
m_f1 = f2;
return;
}
coord_type x1 = m_x1;
coord_type y1 = m_y1;
unsigned f1 = m_f1;
coord_type y3, y4;
unsigned f3, f4;
switch(((f1 & 5) << 1) | (f2 & 5))
{
case 0: // Visible by X
line_clip_y(ras, x1, y1, x2, y2, f1, f2);
break;
case 1: // x2 > clip.x2
y3 = y1 + Conv::mul_div(m_clip_box.x2-x1, y2-y1, x2-x1);
f3 = clipping_flags_y(y3, m_clip_box);
line_clip_y(ras, x1, y1, m_clip_box.x2, y3, f1, f3);
line_clip_y(ras, m_clip_box.x2, y3, m_clip_box.x2, y2, f3, f2);
break;
case 2: // x1 > clip.x2
y3 = y1 + Conv::mul_div(m_clip_box.x2-x1, y2-y1, x2-x1);
f3 = clipping_flags_y(y3, m_clip_box);
line_clip_y(ras, m_clip_box.x2, y1, m_clip_box.x2, y3, f1, f3);
line_clip_y(ras, m_clip_box.x2, y3, x2, y2, f3, f2);
break;
case 3: // x1 > clip.x2 && x2 > clip.x2
line_clip_y(ras, m_clip_box.x2, y1, m_clip_box.x2, y2, f1, f2);
break;
case 4: // x2 < clip.x1
y3 = y1 + Conv::mul_div(m_clip_box.x1-x1, y2-y1, x2-x1);
f3 = clipping_flags_y(y3, m_clip_box);
line_clip_y(ras, x1, y1, m_clip_box.x1, y3, f1, f3);
line_clip_y(ras, m_clip_box.x1, y3, m_clip_box.x1, y2, f3, f2);
break;
case 6: // x1 > clip.x2 && x2 < clip.x1
y3 = y1 + Conv::mul_div(m_clip_box.x2-x1, y2-y1, x2-x1);
y4 = y1 + Conv::mul_div(m_clip_box.x1-x1, y2-y1, x2-x1);
f3 = clipping_flags_y(y3, m_clip_box);
f4 = clipping_flags_y(y4, m_clip_box);
line_clip_y(ras, m_clip_box.x2, y1, m_clip_box.x2, y3, f1, f3);
line_clip_y(ras, m_clip_box.x2, y3, m_clip_box.x1, y4, f3, f4);
line_clip_y(ras, m_clip_box.x1, y4, m_clip_box.x1, y2, f4, f2);
break;
case 8: // x1 < clip.x1
y3 = y1 + Conv::mul_div(m_clip_box.x1-x1, y2-y1, x2-x1);
f3 = clipping_flags_y(y3, m_clip_box);
line_clip_y(ras, m_clip_box.x1, y1, m_clip_box.x1, y3, f1, f3);
line_clip_y(ras, m_clip_box.x1, y3, x2, y2, f3, f2);
break;
case 9: // x1 < clip.x1 && x2 > clip.x2
y3 = y1 + Conv::mul_div(m_clip_box.x1-x1, y2-y1, x2-x1);
y4 = y1 + Conv::mul_div(m_clip_box.x2-x1, y2-y1, x2-x1);
f3 = clipping_flags_y(y3, m_clip_box);
f4 = clipping_flags_y(y4, m_clip_box);
line_clip_y(ras, m_clip_box.x1, y1, m_clip_box.x1, y3, f1, f3);
line_clip_y(ras, m_clip_box.x1, y3, m_clip_box.x2, y4, f3, f4);
line_clip_y(ras, m_clip_box.x2, y4, m_clip_box.x2, y2, f4, f2);
break;
case 12: // x1 < clip.x1 && x2 < clip.x1
line_clip_y(ras, m_clip_box.x1, y1, m_clip_box.x1, y2, f1, f2);
break;
}
m_f1 = f2;
}
else
{
ras.line(Conv::xi(m_x1), Conv::yi(m_y1),
Conv::xi(x2), Conv::yi(y2));
}
m_x1 = x2;
m_y1 = y2;
}
private:
rect_type m_clip_box;
coord_type m_x1;
coord_type m_y1;
unsigned m_f1;
bool m_clipping;
};
//---------------------------------------------------rasterizer_sl_no_clip
class rasterizer_sl_no_clip
{
public:
typedef ras_conv_int conv_type;
typedef int coord_type;
rasterizer_sl_no_clip() : m_x1(0), m_y1(0) {}
void reset_clipping() {}
void clip_box(coord_type /*x1*/, coord_type /*y1*/, coord_type /*x2*/, coord_type /*y2*/) {}
void move_to(coord_type x1, coord_type y1) { m_x1 = x1; m_y1 = y1; }
template<class Rasterizer>
void line_to(Rasterizer& ras, coord_type x2, coord_type y2)
{
ras.line(m_x1, m_y1, x2, y2);
m_x1 = x2;
m_y1 = y2;
}
private:
int m_x1, m_y1;
};
// -----rasterizer_sl_clip_int
// -----rasterizer_sl_clip_int_sat
// -----rasterizer_sl_clip_int_3x
// -----rasterizer_sl_clip_dbl
// -----rasterizer_sl_clip_dbl_3x
//------------------------------------------------------------------------
typedef rasterizer_sl_clip<ras_conv_int> rasterizer_sl_clip_int;
typedef rasterizer_sl_clip<ras_conv_int_sat> rasterizer_sl_clip_int_sat;
typedef rasterizer_sl_clip<ras_conv_int_3x> rasterizer_sl_clip_int_3x;
typedef rasterizer_sl_clip<ras_conv_dbl> rasterizer_sl_clip_dbl;
typedef rasterizer_sl_clip<ras_conv_dbl_3x> rasterizer_sl_clip_dbl_3x;
}
#endif
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