mapnik/agg/src/agg_trans_double_path.cpp
2006-01-31 23:09:52 +00:00

273 lines
7.9 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
//----------------------------------------------------------------------------
#include "agg_math.h"
#include "agg_trans_double_path.h"
namespace agg
{
//------------------------------------------------------------------------
trans_double_path::trans_double_path() :
m_kindex1(0.0),
m_kindex2(0.0),
m_base_length(0.0),
m_base_height(1.0),
m_status1(initial),
m_status2(initial),
m_preserve_x_scale(true)
{
}
//------------------------------------------------------------------------
void trans_double_path::reset()
{
m_src_vertices1.remove_all();
m_src_vertices2.remove_all();
m_kindex1 = 0.0;
m_kindex1 = 0.0;
m_status1 = initial;
m_status2 = initial;
}
//------------------------------------------------------------------------
void trans_double_path::move_to1(double x, double y)
{
if(m_status1 == initial)
{
m_src_vertices1.modify_last(vertex_dist(x, y));
m_status1 = making_path;
}
else
{
line_to1(x, y);
}
}
//------------------------------------------------------------------------
void trans_double_path::line_to1(double x, double y)
{
if(m_status1 == making_path)
{
m_src_vertices1.add(vertex_dist(x, y));
}
}
//------------------------------------------------------------------------
void trans_double_path::move_to2(double x, double y)
{
if(m_status2 == initial)
{
m_src_vertices2.modify_last(vertex_dist(x, y));
m_status2 = making_path;
}
else
{
line_to2(x, y);
}
}
//------------------------------------------------------------------------
void trans_double_path::line_to2(double x, double y)
{
if(m_status2 == making_path)
{
m_src_vertices2.add(vertex_dist(x, y));
}
}
//------------------------------------------------------------------------
double trans_double_path::finalize_path(vertex_storage& vertices)
{
unsigned i;
double dist;
double d;
vertices.close(false);
if(vertices.size() > 2)
{
if(vertices[vertices.size() - 2].dist * 10.0 <
vertices[vertices.size() - 3].dist)
{
d = vertices[vertices.size() - 3].dist +
vertices[vertices.size() - 2].dist;
vertices[vertices.size() - 2] =
vertices[vertices.size() - 1];
vertices.remove_last();
vertices[vertices.size() - 2].dist = d;
}
}
dist = 0;
for(i = 0; i < vertices.size(); i++)
{
vertex_dist& v = vertices[i];
d = v.dist;
v.dist = dist;
dist += d;
}
return (vertices.size() - 1) / dist;
}
//------------------------------------------------------------------------
void trans_double_path::finalize_paths()
{
if(m_status1 == making_path && m_src_vertices1.size() > 1 &&
m_status2 == making_path && m_src_vertices2.size() > 1)
{
m_kindex1 = finalize_path(m_src_vertices1);
m_kindex2 = finalize_path(m_src_vertices2);
m_status1 = ready;
m_status2 = ready;
}
}
//------------------------------------------------------------------------
double trans_double_path::total_length1() const
{
if(m_base_length >= 1e-10) return m_base_length;
return (m_status1 == ready) ?
m_src_vertices1[m_src_vertices1.size() - 1].dist :
0.0;
}
//------------------------------------------------------------------------
double trans_double_path::total_length2() const
{
if(m_base_length >= 1e-10) return m_base_length;
return (m_status2 == ready) ?
m_src_vertices2[m_src_vertices2.size() - 1].dist :
0.0;
}
//------------------------------------------------------------------------
void trans_double_path::transform1(const vertex_storage& vertices,
double kindex, double kx,
double *x, double* y) const
{
double x1 = 0.0;
double y1 = 0.0;
double dx = 1.0;
double dy = 1.0;
double d = 0.0;
double dd = 1.0;
*x *= kx;
if(*x < 0.0)
{
// Extrapolation on the left
//--------------------------
x1 = vertices[0].x;
y1 = vertices[0].y;
dx = vertices[1].x - x1;
dy = vertices[1].y - y1;
dd = vertices[1].dist - vertices[0].dist;
d = *x;
}
else
if(*x > vertices[vertices.size() - 1].dist)
{
// Extrapolation on the right
//--------------------------
unsigned i = vertices.size() - 2;
unsigned j = vertices.size() - 1;
x1 = vertices[j].x;
y1 = vertices[j].y;
dx = x1 - vertices[i].x;
dy = y1 - vertices[i].y;
dd = vertices[j].dist - vertices[i].dist;
d = *x - vertices[j].dist;
}
else
{
// Interpolation
//--------------------------
unsigned i = 0;
unsigned j = vertices.size() - 1;
if(m_preserve_x_scale)
{
unsigned k;
for(i = 0; (j - i) > 1; )
{
if(*x < vertices[k = (i + j) >> 1].dist)
{
j = k;
}
else
{
i = k;
}
}
d = vertices[i].dist;
dd = vertices[j].dist - d;
d = *x - d;
}
else
{
i = unsigned(*x * kindex);
j = i + 1;
dd = vertices[j].dist - vertices[i].dist;
d = ((*x * kindex) - i) * dd;
}
x1 = vertices[i].x;
y1 = vertices[i].y;
dx = vertices[j].x - x1;
dy = vertices[j].y - y1;
}
*x = x1 + dx * d / dd;
*y = y1 + dy * d / dd;
}
//------------------------------------------------------------------------
void trans_double_path::transform(double *x, double *y) const
{
if(m_status1 == ready && m_status2 == ready)
{
if(m_base_length > 1e-10)
{
*x *= m_src_vertices1[m_src_vertices1.size() - 1].dist /
m_base_length;
}
double x1 = *x;
double y1 = *y;
double x2 = *x;
double y2 = *y;
double dd = m_src_vertices2[m_src_vertices2.size() - 1].dist /
m_src_vertices1[m_src_vertices1.size() - 1].dist;
transform1(m_src_vertices1, m_kindex1, 1.0, &x1, &y1);
transform1(m_src_vertices2, m_kindex2, dd, &x2, &y2);
*x = x1 + *y * (x2 - x1) / m_base_height;
*y = y1 + *y * (y2 - y1) / m_base_height;
}
}
}