mapnik/agg/include/agg_bounding_rect.h

117 lines
3.5 KiB
C
Raw Permalink Normal View History

2006-01-31 23:09:52 +00:00
//----------------------------------------------------------------------------
// 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
//----------------------------------------------------------------------------
//
// bounding_rect function template
//
//----------------------------------------------------------------------------
#ifndef AGG_BOUNDING_RECT_INCLUDED
#define AGG_BOUNDING_RECT_INCLUDED
#include "agg_basics.h"
namespace agg
{
//-----------------------------------------------------------bounding_rect
template<class VertexSource, class GetId, class CoordT>
bool bounding_rect(VertexSource& vs, GetId& gi,
unsigned start, unsigned num,
CoordT* x1, CoordT* y1, CoordT* x2, CoordT* y2)
{
unsigned i;
double x;
double y;
bool first = true;
*x1 = CoordT(1);
*y1 = CoordT(1);
*x2 = CoordT(0);
*y2 = CoordT(0);
for(i = 0; i < num; i++)
{
vs.rewind(gi[start + i]);
unsigned cmd;
while(!is_stop(cmd = vs.vertex(&x, &y)))
{
if(is_vertex(cmd))
{
if(first)
{
*x1 = CoordT(x);
*y1 = CoordT(y);
*x2 = CoordT(x);
*y2 = CoordT(y);
first = false;
}
else
{
if(CoordT(x) < *x1) *x1 = CoordT(x);
if(CoordT(y) < *y1) *y1 = CoordT(y);
if(CoordT(x) > *x2) *x2 = CoordT(x);
if(CoordT(y) > *y2) *y2 = CoordT(y);
}
}
}
}
return *x1 <= *x2 && *y1 <= *y2;
}
//-----------------------------------------------------bounding_rect_single
template<class VertexSource, class CoordT>
bool bounding_rect_single(VertexSource& vs, unsigned path_id,
CoordT* x1, CoordT* y1, CoordT* x2, CoordT* y2)
{
double x;
double y;
bool first = true;
*x1 = CoordT(1);
*y1 = CoordT(1);
*x2 = CoordT(0);
*y2 = CoordT(0);
vs.rewind(path_id);
unsigned cmd;
while(!is_stop(cmd = vs.vertex(&x, &y)))
{
if(is_vertex(cmd))
{
if(first)
{
*x1 = CoordT(x);
*y1 = CoordT(y);
*x2 = CoordT(x);
*y2 = CoordT(y);
first = false;
}
else
{
if(CoordT(x) < *x1) *x1 = CoordT(x);
if(CoordT(y) < *y1) *y1 = CoordT(y);
if(CoordT(x) > *x2) *x2 = CoordT(x);
if(CoordT(y) > *y2) *y2 = CoordT(y);
}
}
}
return *x1 <= *x2 && *y1 <= *y2;
}
}
#endif