[geos-devel] linearRing relation

[strk at refractions.net]

A LinearRing is considered a LineString. If you construct
two polygon with those linearrings as shell you'd get the
expected result.

--strk;

On Wed, May 24, 2006 at 11:32:04AM +0800, zhangjing wrote:
> hi,
> 
> Does LinearRing support relational operator? , i have the following code which gives wrong result.
> 
> 		
> 		
> 		double xmin,ymin,xmax,ymax;
> 		
> 		GEOSCoordSeq seq1=GEOSCoordSeq_create(5,2);
> 		xmin=0,0,ymin=0.0,xmax=5.0,ymax=5.0;
> 		GEOSCoordSeq_setX(seq1,0,xmin),GEOSCoordSeq_setY(seq1,0,ymin);
> 		GEOSCoordSeq_setX(seq1,1,xmax),GEOSCoordSeq_setY(seq1,1,ymin);
> 		GEOSCoordSeq_setX(seq1,2,xmax),GEOSCoordSeq_setY(seq1,2,ymax);
> 		GEOSCoordSeq_setX(seq1,3,xmin),GEOSCoordSeq_setY(seq1,3,ymax);
> 		GEOSCoordSeq_setX(seq1,4,xmin),GEOSCoordSeq_setY(seq1,4,ymin);
> 		GEOSGeom g1=GEOSGeom_createLinearRing(seq1);
> 
> 		GEOSCoordSeq seq2=GEOSCoordSeq_create(5,2);
> 		xmin=2,0,ymin=2.0,xmax=3.0,ymax=3.0;
> 		GEOSCoordSeq_setX(seq2,0,xmin),GEOSCoordSeq_setY(seq2,0,ymin);
> 		GEOSCoordSeq_setX(seq2,1,xmax),GEOSCoordSeq_setY(seq2,1,ymin);
> 		GEOSCoordSeq_setX(seq2,2,xmax),GEOSCoordSeq_setY(seq2,2,ymax);
> 		GEOSCoordSeq_setX(seq2,3,xmin),GEOSCoordSeq_setY(seq2,3,ymax);
> 		GEOSCoordSeq_setX(seq2,4,xmin),GEOSCoordSeq_setY(seq2,4,ymin);
> 		GEOSGeom g2=GEOSGeom_createLinearRing(seq2);
> 
> 		char ch=GEOSContains(g1,g2);
> 
> 		//ch == 0
> 
> Thanks
> Jing Zhang