Hi All

I maintain the MemoryLayerSaver plugin and I'm looking for some feedback on the 
next iteration of the plugin.

Currently the plugin saves all memory provider layers as GML files alongside 
the project file, creating 2 files for each layer.  So for example there if 
there is a layer called scratch point then you might have files called

tms1.qgs
tms1.qgs.md_Scratch_point20120814084820149.gml
tms1.qgs.md_Scratch_point20120814084820149.xsd
This is done using the OGR GML driver, and the latest version of this has 
created some incompatibility issues.

What I am proposing is to the replace the GML files with a single binary file, 
say

tms1.qgs
tms1.qgs.mldata

This will contain the data from all the memory layers, serialized in a portable 
but otherwise unusable binary format.  By portable here I mean that the project 
can be moved to a different machine/platform and the memory layers should load 
properly.  The file is only useful for reading the layers back into QGIS, not 
for accessing the data with any other utilities.  I believe that this is 
consistent with the intent of memory layers - they are just for working on in 
QGis - and if you want to save them to another format then you save them to the 
format of your choice from QGis.

I will upload an experimental version 2.0 of the plugin which implements this 
to plugins.qgis.org

I have considered another format, which is an SQLite database.  However this 
creates another set of issues in mapping layers, data types, etc to SQLite 
formats and back again.  I probably would not use spatialite, as this would add 
another dependency on the Memory Layer Saver.  Ideally the MemoryLayerSaver 
should be a core C++ plugin, so that it has no other dependencies (ie doesn't 
depend on python either).

Any thoughts or feedback on this direction are welcome.

Thanks
Chris
This message contains information, which is confidential and may be subject to 
legal privilege. If you are not the intended recipient, you must not peruse, 
use, disseminate, distribute or copy this message. If you have received this 
message in error, please notify us immediately (Phone 0800 665 463 or 
[email protected]) and destroy the original message. LINZ accepts no 
responsibility for changes to this email, or for any attachments, after its 
transmission from LINZ. Thank You.
_______________________________________________
Qgis-user mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/qgis-user

Reply via email to