[Gdal-dev] Possible bug in getGeometryType() version 1.3.0

[Frank Warmerdam]

On 10/10/05, Chapman, Martin <MChapman at sanz.com> wrote:
> Sean,
>
> Ok, I think I figured out the bug.  The basic problem I think is that the shape reader function SHPReadOGRObject () in shape2ogr.cpp creates the OGRPoint object with x, y, z and in turn the OGRPoint class has an original dimension of 3.  Then he (Frank) calls the function setCoordinateDimension(2) if the shape type is SHPT_POINT.  The problem being that the function setCoordinateDimension is a virtual function defined and implemented in ogrgeometry.h/.cpp.  OGRLineString and OGRPolygon override this virtual function and call Make2D() when the coord dimension is reduced to 2.  OGRPoint does not override this function.  The result is that the base class function setCoordinateDimension() in ogrgeometry gets called for points, and the Make2D() function is never called.  The solution is to implement the virtual function setCoordinateDimension() in the OGRPoint class and call Make2D() when dimension == 2.

Martin / Sean,

I'm not sure I follow the issue here.  You report that
GetGeometryType() is returning an invalid value.  What value is
it returning?  Is it just returning a wkbPoint25D?   You mention
you are using 1.3.0.  Perhaps you should upgrade to 1.3.1.  There
was some sort of fix in geometry dimension handling for points
after the 1.3.0 release.

Best regards,
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