[GRASS-dev] Principle G3D library question

[Soeren Gebbert]

Hi Maris,
the new rater3d ascii header looks like this now:

version: grass7
order: nsbt
north: 80.000000
south: 0.000000
east: 120.000000
west: 0.000000
top: 50.000000
bottom: 0.000000
rows: 8
cols: 12
levels: 5

The options "version" and "order" are introduced with my changes on
the g3d library in grass7. The manual page of the svn version of
r3.out.ascii in grass7 explains a bit more.

Best regards
Soeren

2011/6/21 Maris Nartiss <maris.gis at gmail.com>:
> (Still haven't looked at code) - I hope GRASS7 files will have a
> version number in header to be future-proof.
>
> Maris.
>
> 2011/6/21 Soeren Gebbert <soerengebbert at googlemail.com>:
>> Hi Maris,
>>
>> 2011/6/21 Maris Nartiss <maris.gis at gmail.com>:
>>> Hello,
>>> It's not an backporting of header it's about GRASS6 being able to
>>> distinguish GRASS7 format g3d files. I have not peaked into code if
>>> there such feature exists. If not, it should be implemented to prevent
>>> GRASS6 failures (or worse - data corruption) on GRASS7 files.
>>
>> I see, good point!
>>
>> The grass6 implementation checks for valid header:
>>
>> static void readHeaderString(FILE * fp, char *valueString, double *value)
>> {
>>    static char format[100];
>>
>>    /* to avoid buffer overflows we use snprintf */
>>    G_snprintf(format, 100, "%s %%lf", valueString);
>>    if (fscanf(fp, format, value) != 1) {
>>        G_debug(0, "bad value for [%s]", valueString);
>>        fatalError("readHeaderString: header value invalid");
>>    }
>>    while (fgetc(fp) != '\n') ;
>> }
>>
>> I think this should prevent the import of new grass7 volume ascii
>> files in grass6. The grass6 import will break in when the new lines of
>> the grass7 header are parsed.
>>
>> Best regards
>> Soeren
>>
>