[gdal-dev] Using GRASSDataset

[Frank Warmerdam]

Aleksey,

The problems are that the GDAL GRASS support doesn't recognise null values
represented as nan's for floating point values. I will try to fix this
tomorrow. Tonight I have committed changes to the grass support so that
the min/max value from the range file are read and this much is working well.

Part of the problem with the null support is that GDAL only supports null
pixels via a special "nodata" value, not via a flag separate from the
pixel data values themselves. This is OK for floating point where it is
easy to segregate a nodata value, but for byte or uint16 values there may
be no "spare" values to use.

Best regards,

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