//----------------------------------------------------------------------------
// 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.
//----------------------------------------------------------------------------
//
// Adaptation for 32-bit screen coordinates (scanline32_p) has been sponsored by
// Liberty Technology Systems, Inc., visit http://lib-sys.com
//
// Liberty Technology Systems, Inc. is the provider of
// PostScript and PDF technology for software developers.
//
//----------------------------------------------------------------------------
#ifndef AGG_SCANLINE_P_INCLUDED
#define AGG_SCANLINE_P_INCLUDED
#include "agg_array.h"
namespace agg
{
//=============================================================scanline_p8
//
// This is a general purpose scaline container which supports the interface
// used in the rasterizer::render(). See description of scanline_u8
// for details.
//
//------------------------------------------------------------------------
class scanline_p8
{
public:
typedef scanline_p8 self_type;
typedef int8u cover_type;
typedef int16 coord_type;
//--------------------------------------------------------------------
struct span
{
coord_type x;
coord_type len; // If negative, it's a solid span, covers is valid
const cover_type* covers;
};
typedef span* iterator;
typedef const span* const_iterator;
scanline_p8() :
m_last_x(0x7FFFFFF0),
m_covers(),
m_cover_ptr(0),
m_spans(),
m_cur_span(0)
{
}
//--------------------------------------------------------------------
void reset(int min_x, int max_x)
{
unsigned max_len = max_x - min_x + 3;
if(max_len > m_spans.size())
{
m_spans.resize(max_len);
m_covers.resize(max_len);
}
m_last_x = 0x7FFFFFF0;
m_cover_ptr = &m_covers[0];
m_cur_span = &m_spans[0];
m_cur_span->len = 0;
}
//--------------------------------------------------------------------
void add_cell(int x, unsigned cover)
{
*m_cover_ptr = (cover_type)cover;
if(x == m_last_x+1 && m_cur_span->len > 0)
{
m_cur_span->len++;
}
else
{
m_cur_span++;
m_cur_span->covers = m_cover_ptr;
m_cur_span->x = (int16)x;
m_cur_span->len = 1;
}
m_last_x = x;
m_cover_ptr++;
}
//--------------------------------------------------------------------
void add_cells(int x, unsigned len, const cover_type* covers)
{
memcpy(m_cover_ptr, covers, len * sizeof(cover_type));
if(x == m_last_x+1 && m_cur_span->len > 0)
{
m_cur_span->len += (int16)len;
}
else
{
m_cur_span++;
m_cur_span->covers = m_cover_ptr;
m_cur_span->x = (int16)x;
m_cur_span->len = (int16)len;
}
m_cover_ptr += len;
m_last_x = x + len - 1;
}
//--------------------------------------------------------------------
void add_span(int x, unsigned len, unsigned cover)
{
if(x == m_last_x+1 &&
m_cur_span->len < 0 &&
cover == *m_cur_span->covers)
{
m_cur_span->len -= (int16)len;
}
else
{
*m_cover_ptr = (cover_type)cover;
m_cur_span++;
m_cur_span->covers = m_cover_ptr++;
m_cur_span->x = (int16)x;
m_cur_span->len = (int16)(-int(len));
}
m_last_x = x + len - 1;
}
//--------------------------------------------------------------------
void finalize(int y)
{
m_y = y;
}
//--------------------------------------------------------------------
void reset_spans()
{
m_last_x = 0x7FFFFFF0;
m_cover_ptr = &m_covers[0];
m_cur_span = &m_spans[0];
m_cur_span->len = 0;
}
//--------------------------------------------------------------------
int y() const { return m_y; }
unsigned num_spans() const { return unsigned(m_cur_span - &m_spans[0]); }
const_iterator begin() const { return &m_spans[1]; }
private:
scanline_p8(const self_type&);
const self_type& operator = (const self_type&);
int m_last_x;
int m_y;
pod_array<cover_type> m_covers;
cover_type* m_cover_ptr;
pod_array<span> m_spans;
span* m_cur_span;
};
//==========================================================scanline32_p8
class scanline32_p8
{
public:
typedef scanline32_p8 self_type;
typedef int8u cover_type;
typedef int32 coord_type;
struct span
{
span() {}
span(coord_type x_, coord_type len_, const cover_type* covers_) :
x(x_), len(len_), covers(covers_) {}
coord_type x;
coord_type len; // If negative, it's a solid span, covers is valid
const cover_type* covers;
};
typedef pod_bvector<span, 4> span_array_type;
//--------------------------------------------------------------------
class const_iterator
{
public:
const_iterator(const span_array_type& spans) :
m_spans(spans),
m_span_idx(0)
{}
const span& operator*() const { return m_spans[m_span_idx]; }
const span* operator->() const { return &m_spans[m_span_idx]; }
void operator ++ () { ++m_span_idx; }
private:
const span_array_type& m_spans;
unsigned m_span_idx;
};
//--------------------------------------------------------------------
scanline32_p8() :
m_max_len(0),
m_last_x(0x7FFFFFF0),
m_covers(),
m_cover_ptr(0)
{
}
//--------------------------------------------------------------------
void reset(int min_x, int max_x)
{
unsigned max_len = max_x - min_x + 3;
if(max_len > m_covers.size())
{
m_covers.resize(max_len);
}
m_last_x = 0x7FFFFFF0;
m_cover_ptr = &m_covers[0];
m_spans.remove_all();
}
//--------------------------------------------------------------------
void add_cell(int x, unsigned cover)
{
*m_cover_ptr = cover_type(cover);
if(x == m_last_x+1 && m_spans.size() && m_spans.last().len > 0)
{
m_spans.last().len++;
}
else
{
m_spans.add(span(coord_type(x), 1, m_cover_ptr));
}
m_last_x = x;
m_cover_ptr++;
}
//--------------------------------------------------------------------
void add_cells(int x, unsigned len, const cover_type* covers)
{
memcpy(m_cover_ptr, covers, len * sizeof(cover_type));
if(x == m_last_x+1 && m_spans.size() && m_spans.last().len > 0)
{
m_spans.last().len += coord_type(len);
}
else
{
m_spans.add(span(coord_type(x), coord_type(len), m_cover_ptr));
}
m_cover_ptr += len;
m_last_x = x + len - 1;
}
//--------------------------------------------------------------------
void add_span(int x, unsigned len, unsigned cover)
{
if(x == m_last_x+1 &&
m_spans.size() &&
m_spans.last().len < 0 &&
cover == *m_spans.last().covers)
{
m_spans.last().len -= coord_type(len);
}
else
{
*m_cover_ptr = cover_type(cover);
m_spans.add(span(coord_type(x), -coord_type(len), m_cover_ptr++));
}
m_last_x = x + len - 1;
}
//--------------------------------------------------------------------
void finalize(int y)
{
m_y = y;
}
//--------------------------------------------------------------------
void reset_spans()
{
m_last_x = 0x7FFFFFF0;
m_cover_ptr = &m_covers[0];
m_spans.remove_all();
}
//--------------------------------------------------------------------
int y() const { return m_y; }
unsigned num_spans() const { return m_spans.size(); }
const_iterator begin() const { return const_iterator(m_spans); }
private:
scanline32_p8(const self_type&);
const self_type& operator = (const self_type&);
unsigned m_max_len;
int m_last_x;
int m_y;
pod_array<cover_type> m_covers;
cover_type* m_cover_ptr;
span_array_type m_spans;
};
}
#endif
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