sij/mapnik
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

+ avoid creating two coincident vertices (needs more testing)

Browse source
This commit is contained in:
artemp 2013-02-12 15:51:40 +00:00
parent b50330c40e
commit 8b757a1c7e
1 changed files with 50 additions and 49 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

99
deps/agg/include/agg_clip_liang_barsky.h vendored
View file

@ -2,8 +2,8 @@
// 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.
// 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.
//
@ -13,7 +13,7 @@
// http://www.antigrain.com
//----------------------------------------------------------------------------
//
// Liang-Barsky clipping
// Liang-Barsky clipping
//
//----------------------------------------------------------------------------
#ifndef AGG_CLIP_LIANG_BARSKY_INCLUDED
@ -36,7 +36,7 @@ namespace agg
};
//----------------------------------------------------------clipping_flags
// Determine the clipping code of the vertex according to the
// Determine the clipping code of the vertex according to the
// Cyrus-Beck line clipping algorithm
//
// | |
@ -52,7 +52,7 @@ namespace agg
// | |
// clip_box.x1 clip_box.x2
//
//
//
template<class T>
inline unsigned clipping_flags(T x, T y, const rect_base<T>& clip_box)
{
@ -87,7 +87,7 @@ namespace agg
const double nearzero = 1e-30;
double deltax = x2 - x1;
double deltay = y2 - y1;
double deltay = y2 - y1;
double xin;
double xout;
double yin;
@ -95,52 +95,52 @@ namespace agg
double tinx;
double tiny;
double toutx;
double touty;
double touty;
double tin1;
double tin2;
double tout1;
unsigned np = 0;
if(deltax == 0.0)
{
if(deltax == 0.0)
{
// bump off of the vertical
deltax = (x1 > clip_box.x1) ? -nearzero : nearzero;
}
if(deltay == 0.0)
{
// bump off of the horizontal
if(deltay == 0.0)
{
// bump off of the horizontal
deltay = (y1 > clip_box.y1) ? -nearzero : nearzero;
}
if(deltax > 0.0)
{
if(deltax > 0.0)
{
// points to right
xin = clip_box.x1;
xout = clip_box.x2;
}
else
else
{
xin = clip_box.x2;
xout = clip_box.x1;
}
if(deltay > 0.0)
if(deltay > 0.0)
{
// points up
yin = clip_box.y1;
yout = clip_box.y2;
}
else
else
{
yin = clip_box.y2;
yout = clip_box.y1;
}
tinx = (xin - x1) / deltax;
tiny = (yin - y1) / deltay;
if (tinx < tiny)
if (tinx < tiny)
{
// hits x first
tin1 = tinx;
@ -152,10 +152,10 @@ namespace agg
tin1 = tiny;
tin2 = tinx;
}
if(tin1 <= 1.0)
if(tin1 <= 1.0)
{
if(0.0 < tin1)
if(0.0 < tin1)
{
*x++ = (T)xin;
*y++ = (T)yin;
@ -166,21 +166,21 @@ namespace agg
{
toutx = (xout - x1) / deltax;
touty = (yout - y1) / deltay;
tout1 = (toutx < touty) ? toutx : touty;
if(tin2 > 0.0 || tout1 > 0.0)
if(tin2 > 0.0 || tout1 > 0.0)
{
if(tin2 <= tout1)
if(tin2 <= tout1)
{
if(tin2 > 0.0)
if(tin2 > 0.0)
{
if(tinx > tiny)
if(tinx > tiny)
{
*x++ = (T)xin;
*y++ = (T)(y1 + tinx * deltay);
}
else
else
{
*x++ = (T)(x1 + tiny * deltax);
*y++ = (T)yin;
@ -188,34 +188,35 @@ namespace agg
++np;
}
if(tout1 < 1.0)
if(tout1 < 1.0)
{
if(toutx < touty)
if(toutx < touty)
{
*x++ = (T)xout;
*y++ = (T)(y1 + toutx * deltay);
}
else
else
{
*x++ = (T)(x1 + touty * deltax);
*y++ = (T)yout;
}
++np;
}
else
else if(*x != x2 && *y != y2)
{
*x++ = x2;
*y++ = y2;
++np;
}
++np;
}
else
else
{
if(tinx > tiny)
if(tinx > tiny)
{
*x++ = (T)xin;
*y++ = (T)yout;
}
else
else
{
*x++ = (T)xout;
*y++ = (T)yin;
@ -231,8 +232,8 @@ namespace agg
//----------------------------------------------------------------------------
template<class T>
bool clip_move_point(T x1, T y1, T x2, T y2,
const rect_base<T>& clip_box,
bool clip_move_point(T x1, T y1, T x2, T y2,
const rect_base<T>& clip_box,
T* x, T* y, unsigned flags)
{
T bound;
@ -281,14 +282,14 @@ namespace agg
return 0;
}
if((f1 & clipping_flags_x_clipped) != 0 &&
if((f1 & clipping_flags_x_clipped) != 0 &&
(f1 & clipping_flags_x_clipped) == (f2 & clipping_flags_x_clipped))
{
// Fully clipped
return 4;
}
if((f1 & clipping_flags_y_clipped) != 0 &&
if((f1 & clipping_flags_y_clipped) != 0 &&
(f1 & clipping_flags_y_clipped) == (f2 & clipping_flags_y_clipped))
{
// Fully clipped
@ -299,25 +300,25 @@ namespace agg
T ty1 = *y1;
T tx2 = *x2;
T ty2 = *y2;
if(f1)
{
if(!clip_move_point(tx1, ty1, tx2, ty2, clip_box, x1, y1, f1))
if(f1)
{
if(!clip_move_point(tx1, ty1, tx2, ty2, clip_box, x1, y1, f1))
{
return 4;
}
if(*x1 == *x2 && *y1 == *y2)
if(*x1 == *x2 && *y1 == *y2)
{
return 4;
}
ret |= 1;
}
if(f2)
if(f2)
{
if(!clip_move_point(tx1, ty1, tx2, ty2, clip_box, x2, y2, f2))
{
return 4;
}
if(*x1 == *x2 && *y1 == *y2)
if(*x1 == *x2 && *y1 == *y2)
{
return 4;
}