Yann,<div>About all I can recommend is the vrt format tutorial, <a href="http://www.gdal.org/gdal_vrttut.html">http://www.gdal.org/gdal_vrttut.html</a>, gdal, data model <a href="http://www.gdal.org/gdal_datamodel.html">http://www.gdal.org/gdal_datamodel.html</a>, and driver tutorial, <a href="http://www.gdal.org/gdal_drivertut.html">http://www.gdal.org/gdal_drivertut.html</a> , etc in the gdal online documentation. You might look at the existing gdal/GRASS interface code. I'm not a C programmer yet, so I can't help much there.</div>
<div><br></div><div>Doug <br><br><div class="gmail_quote">On Tue, Mar 19, 2013 at 10:01 PM, Yann Chemin <span dir="ltr"><<a href="mailto:yann.chemin@gmail.com" target="_blank">yann.chemin@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Thank you Doug,<br>
<br>
yes r.patch is a good alternative, but it means writing to disk etc.<br>
Was more thinking of a display memory thingy.<br>
<br>
Been thinking about the virtual rasters indeed, maybe will have a<br>
look, any C code page you could direct me to?<br>
<br>
Cheers,<br>
Yann<br>
<div class="HOEnZb"><div class="h5"><br>
On 20 March 2013 05:39, Newcomb, Doug <<a href="mailto:doug_newcomb@fws.gov">doug_newcomb@fws.gov</a>> wrote:<br>
> Yann,<br>
> If I have a large number of layers, I usually do it from a command line or<br>
> with a script. I done r.patch with over 100 layers in one command ( before<br>
> I discovered gdalbuildvirt :-))<br>
><br>
> Doug<br>
><br>
><br>
> On Tue, Mar 19, 2013 at 4:36 AM, Vaclav Petras <<a href="mailto:wenzeslaus@gmail.com">wenzeslaus@gmail.com</a>> wrote:<br>
>><br>
>> On 19 March 2013 09:31, Yann Chemin <<a href="mailto:yann.chemin@gmail.com">yann.chemin@gmail.com</a>> wrote:<br>
>> > OK found Ctrl+Shift+L in wxGUI<br>
>> ><br>
>> Yes, it is my favorite feature. I use it even to find and add one map.<br>
>><br>
>> However, there is some issue with many layers in layer manager. If you<br>
>> load more than 20 (?) layers (maps) only some of them will be<br>
>> rendered. There were no investigations; maybe it applies only to<br>
>> vectors. And, of course, it is slow.<br>
>><br>
>> > Thanks !<br>
>> > Yann<br>
>> ><br>
>> > On 19 March 2013 13:56, Yann Chemin <<a href="mailto:yann.chemin@gmail.com">yann.chemin@gmail.com</a>> wrote:<br>
>> >> I am dealing with hourly Microwave data that are not covering the<br>
>> >> whole World in each layer.<br>
>> >><br>
>> >> To have a decent presentation map of the data, I'd like to get a set<br>
>> >> (say 30-50 layers) displayed in one go.<br>
>> >><br>
>> >> OK I could do it with the png driver in a script (which is what it may<br>
>> >> eventually become), but for the sake of knowledge, is there a GUI<br>
>> >> option to load a (rather large) set of images in one block without<br>
>> >> having to struggle with a cluttered GIS Manager?<br>
>> >><br>
>> >> Thanks<br>
>> >> Yann<br>
>> >><br>
>> >> --<br>
>> >> Yann Chemin<br>
>> >> Researcher@IWMI<br>
>> >> Skype/FB: yann.chemin<br>
>> ><br>
>> ><br>
>> ><br>
>> > --<br>
>> > Yann Chemin<br>
>> > Researcher@IWMI<br>
>> > Skype/FB: yann.chemin<br>
>> > _______________________________________________<br>
>> > grass-dev mailing list<br>
>> > <a href="mailto:grass-dev@lists.osgeo.org">grass-dev@lists.osgeo.org</a><br>
>> > <a href="http://lists.osgeo.org/mailman/listinfo/grass-dev" target="_blank">http://lists.osgeo.org/mailman/listinfo/grass-dev</a><br>
>> _______________________________________________<br>
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><br>
><br>
><br>
><br>
> --<br>
> Doug Newcomb<br>
> USFWS<br>
> Raleigh, NC<br>
> 919-856-4520 ext. 14 <a href="mailto:doug_newcomb@fws.gov">doug_newcomb@fws.gov</a><br>
> ---------------------------------------------------------------------------------------------------------<br>
> The opinions I express are my own and are not representative of the official<br>
> policy of the U.S.Fish and Wildlife Service or Dept. of the Interior. Life<br>
> is too short for undocumented, proprietary data formats.<br>
<br>
<br>
<br>
--<br>
Yann Chemin<br>
Researcher@IWMI<br>
Skype/FB: yann.chemin<br>
</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div>Doug Newcomb</div><div>USFWS</div><div>Raleigh, NC</div><div>919-856-4520 ext. 14 <a href="mailto:doug_newcomb@fws.gov" target="_blank">doug_newcomb@fws.gov</a></div>
<div>---------------------------------------------------------------------------------------------------------</div><div>The opinions I express are my own and are not representative of the official policy of the U.S.Fish and Wildlife Service or Dept. of the Interior. Life is too short for undocumented, proprietary data formats.</div>
</div>