[Gdal-dev] Geometry Types

[Frank Warmerdam]

On 6/7/05, Michele Sanges <michele.sanges at otomelara.it> wrote:
> Hi all,
> 
> in file 'ogr_core.h' is defined this enum type:
> 
> typedef enum
> {
>      wkbUnknown = 0,
>      wkbPoint = 1,
>      wkbLineString = 2,
>      wkbPolygon = 3,
>      wkbMultiPoint = 4,
>      wkbMultiLineString = 5,
>      wkbMultiPolygon = 6,
>      wkbGeometryCollection = 7,
>      wkbNone = 100,
>      wkbLinearRing = 101,
>      wkbPoint25D = 0x80000001,
>      wkbLineString25D = 0x80000002,
>      wkbPolygon25D = 0x80000003,
>      wkbMultiPoint25D = 0x80000004,
>      wkbMultiLineString25D = 0x80000005,
>      wkbMultiPolygon25D = 0x80000006,
>      wkbGeometryCollection25D = 0x80000007
> } OGRwkbGeometryType;
> 
> 
> Where can i find the description of any of such geometry types, in
> particular the 25D extensions?

Michele,

What sort of information were you looking for?  Many of these codes
correspond in a relatively obvious way to classes derived from OGRGeometry
and can be tracked from:

  http://www.gdal.org/ogr/classOGRGeometry.html

The 25D version are the normal 2D versions, but with a Z value for each vertex.
The geometry classes are based on the OpenGIS Simple Features geometry
model, so looking at the corresponding OGC spectifications could be useful. 

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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