[Gdal-dev] Re: Decoding headers in a MIF file

[Frank Warmerdam]

Jacob Bensabat wrote:
> Hi
> Then the question is where this information is stored ? Or if it is stored
> at all ?
> This information is crucial for rendering as various maps can be in various
> coordinates systems
> and we want to know prior to loading the map how to adapt it.
> Actually shp files also have this kind of header.
> thanks

Jacob,

The OGRLayer::GetExtent() method can be used to fetch the extent of an
individual layer.  For some formats (such as Shapefiles which you mention)
OGR is able to answer this request cheaply by reading bounds from the header.
For MIF format the entire file has to be scanned to get the extents.

Best regards,
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