[gdal-dev] How to access Z Offset and Scale in GTiff?

[Pablo.Angelo at dlr.de]

Hi all,

Is there a way to read / write the Z component in the Geotiff ModelPixelScaleTag and ModelTiepointTag? I mostly work with DEM data, where the vertical resolution of the DEM raster is often stored in this tag.
 
>From the API, one would expect that the RasterBand::GetOffset() and RasterBand::GetScale() should make use of this information, however, it seems that that the GTiff driver does simply ignore the Z entries in ModelPixelScaleTag and ModelTiepointTag.

Would you accept a patch that implements reading and writing the offsets from and to these tags?

Best regards
  Pablo d'Angelo