[gdal-dev] find bounding box of a shapefile

[Frank Warmerdam]

Xiaodong Zhang wrote:
> Hi,
> 
> In order to find the bounding box of polygons (defined in a shapefile), 
> I guess I need to find the minimum x and y coordinates and maximum x and 
> y coordinates and then to form the four corners. In case somebody has 
> already done this, would you like to share your thoughts or code?

Xiaodong,

If you are using OGR, you can just call GetExtent() on the OGRLayer
representing the shapefile.  In the case of the shapefile, the extents
are stored in the header so this is a virtually free operation.

Best regards,
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