[GRASS5] new vector2

Justin Hickey jhickey at hpcc.nectec.or.th
Sun Jan 7 23:56:22 EST 2001

Hi Radim

Hmmm. I think you missed my question. Maybe if I comment on each of your
points it will become clearer.

Radim Blazek wrote:
> - vector file may ben written in big or little endian (no pdp or
>   other) and byte order is specified in header

I don't understand the need for this. The vector file should be simply
written in native byte order, but maintaining this information in the
header could be useful for checking byte order if it is faster than a
system check (I don't know what the system check would be).

> - by default new file will be written in machine native byte order
I think new should be all files. Please explain why only new files
should have the native byte order by default.

>   (later add optional byte order for new files by enviroment
>    variable GRASS_VECTOR_ENDIAN)

I don't understand the need for this.

> - vector modules (library) will work with both little and big endian
>   vector files

I agree with this but the conversion should be handled in the read
function. The modules should not need to be changed.

> - write new module for conversion little <=> big
> - no auto conversion into native format (read only files, files shared
>   by more platforms)
> - vector written in one byte order (big for example) will be updated
>   in that byte order (big) even on machine with some other byte order
>   (little)

I don't understand the need for these three.

> Conversion module may be used to increase speed if files are not in 
> native order.


Jazzman (a.k.a. Justin Hickey)  e-mail: jhickey at hpcc.nectec.or.th
High Performance Computing Center
National Electronics and Computer Technology Center (NECTEC)
Bangkok, Thailand
People who think they know everything are very irritating to those
of us who do.  ---Anonymous

Jazz and Trek Rule!!!

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