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//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.3
// 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_INTERPOLATOR_PERSP_INCLUDED
#define AGG_SPAN_INTERPOLATOR_PERSP_INCLUDED
#include "agg_trans_perspective.h"
#include "agg_dda_line.h"
namespace agg
{
//===========================================span_interpolator_persp_exact
template<unsigned SubpixelShift = 8>
class span_interpolator_persp_exact
{
public:
typedef trans_perspective trans_type;
typedef trans_perspective::iterator_x iterator_type;
enum
{
subpixel_shift = SubpixelShift,
subpixel_size = 1 << subpixel_shift
};
//--------------------------------------------------------------------
span_interpolator_persp_exact() {}
//--------------------------------------------------------------------
// Arbitrary quadrangle transformations
span_interpolator_persp_exact(const double* src, const double* dst)
{
quad_to_quad(src, dst);
}
//--------------------------------------------------------------------
// Direct transformations
span_interpolator_persp_exact(double x1, double y1,
double x2, double y2,
const double* quad)
{
rect_to_quad(x1, y1, x2, y2, quad);
}
//--------------------------------------------------------------------
// Reverse transformations
span_interpolator_persp_exact(const double* quad,
double x1, double y1,
double x2, double y2)
{
quad_to_rect(quad, x1, y1, x2, y2);
}
//--------------------------------------------------------------------
// Set the transformations using two arbitrary quadrangles.
void quad_to_quad(const double* src, const double* dst)
{
m_trans_dir.quad_to_quad(src, dst);
m_trans_inv.quad_to_quad(dst, src);
}
//--------------------------------------------------------------------
// Set the direct transformations, i.e., rectangle -> quadrangle
void rect_to_quad(double x1, double y1, double x2, double y2,
const double* quad)
{
double src[8];
src[0] = src[6] = x1;
src[2] = src[4] = x2;
src[1] = src[3] = y1;
src[5] = src[7] = y2;
quad_to_quad(src, quad);
}
//--------------------------------------------------------------------
// Set the reverse transformations, i.e., quadrangle -> rectangle
void quad_to_rect(const double* quad,
double x1, double y1, double x2, double y2)
{
double dst[8];
dst[0] = dst[6] = x1;
dst[2] = dst[4] = x2;
dst[1] = dst[3] = y1;
dst[5] = dst[7] = y2;
quad_to_quad(quad, dst);
}
//--------------------------------------------------------------------
// Check if the equations were solved successfully
bool is_valid() const { return m_trans_dir.is_valid(); }
//----------------------------------------------------------------
void begin(double x, double y, unsigned len)
{
m_iterator = m_trans_dir.begin(x, y, 1.0);
double xt = m_iterator.x;
double yt = m_iterator.y;
double dx;
double dy;
const double delta = 1/double(subpixel_size);
dx = xt + delta;
dy = yt;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sx1 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
dx = xt;
dy = yt + delta;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sy1 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
x += len;
xt = x;
yt = y;
m_trans_dir.transform(&xt, &yt);
dx = xt + delta;
dy = yt;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sx2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
dx = xt;
dy = yt + delta;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sy2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
m_scale_x = dda2_line_interpolator(sx1, sx2, len);
m_scale_y = dda2_line_interpolator(sy1, sy2, len);
}
//----------------------------------------------------------------
void resynchronize(double xe, double ye, unsigned len)
{
// Assume x1,y1 are equal to the ones at the previous end point
int sx1 = m_scale_x.y();
int sy1 = m_scale_y.y();
// Calculate transformed coordinates at x2,y2
double xt = xe;
double yt = ye;
m_trans_dir.transform(&xt, &yt);
const double delta = 1/double(subpixel_size);
double dx;
double dy;
// Calculate scale by X at x2,y2
dx = xt + delta;
dy = yt;
m_trans_inv.transform(&dx, &dy);
dx -= xe;
dy -= ye;
int sx2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Calculate scale by Y at x2,y2
dx = xt;
dy = yt + delta;
m_trans_inv.transform(&dx, &dy);
dx -= xe;
dy -= ye;
int sy2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Initialize the interpolators
m_scale_x = dda2_line_interpolator(sx1, sx2, len);
m_scale_y = dda2_line_interpolator(sy1, sy2, len);
}
//----------------------------------------------------------------
void operator++()
{
++m_iterator;
++m_scale_x;
++m_scale_y;
}
//----------------------------------------------------------------
void coordinates(int* x, int* y) const
{
*x = int(m_iterator.x * subpixel_size + 0.5);
*y = int(m_iterator.y * subpixel_size + 0.5);
}
//----------------------------------------------------------------
void local_scale(int* x, int* y)
{
*x = m_scale_x.y();
*y = m_scale_y.y();
}
//----------------------------------------------------------------
void transform(double* x, double* y) const
{
m_trans_dir.transform(x, y);
}
private:
trans_type m_trans_dir;
trans_type m_trans_inv;
iterator_type m_iterator;
dda2_line_interpolator m_scale_x;
dda2_line_interpolator m_scale_y;
};
//============================================span_interpolator_persp_lerp
template<unsigned SubpixelShift = 8>
class span_interpolator_persp_lerp
{
public:
typedef trans_perspective trans_type;
enum
{
subpixel_shift = SubpixelShift,
subpixel_size = 1 << subpixel_shift
};
//--------------------------------------------------------------------
span_interpolator_persp_lerp() {}
//--------------------------------------------------------------------
// Arbitrary quadrangle transformations
span_interpolator_persp_lerp(const double* src, const double* dst)
{
quad_to_quad(src, dst);
}
//--------------------------------------------------------------------
// Direct transformations
span_interpolator_persp_lerp(double x1, double y1,
double x2, double y2,
const double* quad)
{
rect_to_quad(x1, y1, x2, y2, quad);
}
//--------------------------------------------------------------------
// Reverse transformations
span_interpolator_persp_lerp(const double* quad,
double x1, double y1,
double x2, double y2)
{
quad_to_rect(quad, x1, y1, x2, y2);
}
//--------------------------------------------------------------------
// Set the transformations using two arbitrary quadrangles.
void quad_to_quad(const double* src, const double* dst)
{
m_trans_dir.quad_to_quad(src, dst);
m_trans_inv.quad_to_quad(dst, src);
}
//--------------------------------------------------------------------
// Set the direct transformations, i.e., rectangle -> quadrangle
void rect_to_quad(double x1, double y1, double x2, double y2,
const double* quad)
{
double src[8];
src[0] = src[6] = x1;
src[2] = src[4] = x2;
src[1] = src[3] = y1;
src[5] = src[7] = y2;
quad_to_quad(src, quad);
}
//--------------------------------------------------------------------
// Set the reverse transformations, i.e., quadrangle -> rectangle
void quad_to_rect(const double* quad,
double x1, double y1, double x2, double y2)
{
double dst[8];
dst[0] = dst[6] = x1;
dst[2] = dst[4] = x2;
dst[1] = dst[3] = y1;
dst[5] = dst[7] = y2;
quad_to_quad(quad, dst);
}
//--------------------------------------------------------------------
// Check if the equations were solved successfully
bool is_valid() const { return m_trans_dir.is_valid(); }
//----------------------------------------------------------------
void begin(double x, double y, unsigned len)
{
// Calculate transformed coordinates at x1,y1
double xt = x;
double yt = y;
m_trans_dir.transform(&xt, &yt);
int x1 = int(xt * subpixel_size);
int y1 = int(yt * subpixel_size);
double dx;
double dy;
const double delta = 1/double(subpixel_size);
// Calculate scale by X at x1,y1
dx = xt + delta;
dy = yt;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sx1 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Calculate scale by Y at x1,y1
dx = xt;
dy = yt + delta;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sy1 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Calculate transformed coordinates at x2,y2
x += len;
xt = x;
yt = y;
m_trans_dir.transform(&xt, &yt);
int x2 = int(xt * subpixel_size);
int y2 = int(yt * subpixel_size);
// Calculate scale by X at x2,y2
dx = xt + delta;
dy = yt;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sx2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Calculate scale by Y at x2,y2
dx = xt;
dy = yt + delta;
m_trans_inv.transform(&dx, &dy);
dx -= x;
dy -= y;
int sy2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Initialize the interpolators
m_coord_x = dda2_line_interpolator(x1, x2, len);
m_coord_y = dda2_line_interpolator(y1, y2, len);
m_scale_x = dda2_line_interpolator(sx1, sx2, len);
m_scale_y = dda2_line_interpolator(sy1, sy2, len);
}
//----------------------------------------------------------------
void resynchronize(double xe, double ye, unsigned len)
{
// Assume x1,y1 are equal to the ones at the previous end point
int x1 = m_coord_x.y();
int y1 = m_coord_y.y();
int sx1 = m_scale_x.y();
int sy1 = m_scale_y.y();
// Calculate transformed coordinates at x2,y2
double xt = xe;
double yt = ye;
m_trans_dir.transform(&xt, &yt);
int x2 = int(xt * subpixel_size);
int y2 = int(yt * subpixel_size);
const double delta = 1/double(subpixel_size);
double dx;
double dy;
// Calculate scale by X at x2,y2
dx = xt + delta;
dy = yt;
m_trans_inv.transform(&dx, &dy);
dx -= xe;
dy -= ye;
int sx2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Calculate scale by Y at x2,y2
dx = xt;
dy = yt + delta;
m_trans_inv.transform(&dx, &dy);
dx -= xe;
dy -= ye;
int sy2 = int(subpixel_size/sqrt(dx*dx + dy*dy)) >> subpixel_shift;
// Initialize the interpolators
m_coord_x = dda2_line_interpolator(x1, x2, len);
m_coord_y = dda2_line_interpolator(y1, y2, len);
m_scale_x = dda2_line_interpolator(sx1, sx2, len);
m_scale_y = dda2_line_interpolator(sy1, sy2, len);
}
//----------------------------------------------------------------
void operator++()
{
++m_coord_x;
++m_coord_y;
++m_scale_x;
++m_scale_y;
}
//----------------------------------------------------------------
void coordinates(int* x, int* y) const
{
*x = m_coord_x.y();
*y = m_coord_y.y();
}
//----------------------------------------------------------------
void local_scale(int* x, int* y)
{
*x = m_scale_x.y();
*y = m_scale_y.y();
}
//----------------------------------------------------------------
void transform(double* x, double* y) const
{
m_trans_dir.transform(x, y);
}
private:
trans_type m_trans_dir;
trans_type m_trans_inv;
dda2_line_interpolator m_coord_x;
dda2_line_interpolator m_coord_y;
dda2_line_interpolator m_scale_x;
dda2_line_interpolator m_scale_y;
};
}
#endif
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