self-hosted/postgis
self-hosted/postgis
1
0
Fork 0
mirror of https://git.osgeo.org/gitea/postgis/postgis synced 2024-10-24 17:12:35 +00:00
Code Issues Packages Projects Releases Wiki Activity

Make polygon pole check a little more general.

Browse source 
git-svn-id: http://svn.osgeo.org/postgis/trunk@4548 b70326c6-7e19-0410-871a-916f4a2858ee
This commit is contained in:
Paul Ramsey 2009-09-29 19:02:09 +00:00
parent c8ec0a6408
commit 6ead7c9f4b
1 changed files with 30 additions and 24 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

54
liblwgeom/lwgeodetic.c
View file

@ -45,36 +45,46 @@ void point_rad2deg(GEOGRAPHIC_POINT *p)
}
/**
* Check to see if this geocentric gbox is wrapped around the north pole.
* Check to see if this geocentric gbox is wrapped around a pole.
* Only makes sense if this gbox originated from a polygon, as it's assuming
* the box is generated from external edges and there's an "interior" which
* contains the pole.
*/
static int gbox_contains_north_pole(GBOX gbox)
static int gbox_check_poles(GBOX *gbox)
{
if( gbox.zmin > 0.0 &&
gbox.xmin < 0.0 && gbox.xmax > 0.0 &&
gbox.ymin < 0.0 && gbox.ymax > 0.0 )
/* Z axis */
if( gbox->xmin < 0.0 && gbox->xmax > 0.0 &&
gbox->ymin < 0.0 && gbox->ymax > 0.0 )
{
if( (gbox->zmin+gbox->zmin)/2 > 0.0 )
gbox->zmax = 1.0;
else
gbox->zmin = -1.0;
return LW_TRUE;
}
return LW_FALSE;
}
/**
* Check to see if this geocentric gbox is wrapped around the south pole.
* Only makes sense if this gbox originated from a polygon, as it's assuming
* the box is generated from external edges and there's an "interior" which
* contains the pole.
*/
static int gbox_contains_south_pole(GBOX gbox)
{
if( gbox.zmax < 0.0 &&
gbox.xmin < 0.0 && gbox.xmax > 0.0 &&
gbox.ymin < 0.0 && gbox.ymax > 0.0 )
/* Y axis */
if( gbox->xmin < 0.0 && gbox->xmax > 0.0 &&
gbox->zmin < 0.0 && gbox->zmax > 0.0 )
{
if( (gbox->ymin+gbox->ymin)/2 > 0.0 )
gbox->ymax = 1.0;
else
gbox->ymin = -1.0;
return LW_TRUE;
}
/* X axis */
if( gbox->ymin < 0.0 && gbox->ymax > 0.0 &&
gbox->zmin < 0.0 && gbox->zmax > 0.0 )
{
if( (gbox->xmin+gbox->xmin)/2 > 0.0 )
gbox->xmax = 1.0;
else
gbox->xmin = -1.0;
return LW_TRUE;
}
return LW_FALSE;
}
@ -917,12 +927,8 @@ static int lwpolygon_calculate_gbox_geodetic(LWPOLY *poly, GBOX *gbox)
}
}
/* If the box wraps the south pole, set zmin to the absolute min. */
if( gbox_contains_south_pole(*gbox) )
gbox->zmin = -1.0;
/* If the box wraps the north pole, set zmax to the absolute max. */
if( gbox_contains_north_pole(*gbox) )
gbox->zmax = 1.0;
/* If the box wraps a poly, push that axis to the absolute min/max as appropriate */
gbox_check_poles(gbox);
return G_SUCCESS;
}