Multi-Thread and GM_ExportRasterEx / GM_ExportElevationEx for self-gridding

codemouse

Mike,

I've seen a bunch of old posts on multi-threading - any 2013 status on multi-threading? Particularly for self-gridding operations with large amounts of exports of rasters, vectors, or elevation?

I've basically already tried to abstract this in c# and once I try anything about 1 thing at a time, GM cannot handle the image export. I figured it's still not in there, but just wanted to check. Thanks!

Parallel.ForEach(requests, new ParallelOptions { MaxDegreeOfParallelism = 1 }, request =>
{
     //run GM_ExportRasterEx here
}

I'll get a JPEG export error on every other thread. I assume it has to do with access to shared libraries (such as lti_dsdk.dll), etc.

Brian

global_mapper

Brian,

The thread safety has improved quite a bit in recent SDK releases, but it's not perfectly safe. You should be safe in the latest SDK (v14.2) to do exports from multiple threads simultaneously so long as you are using different input layers in each thread. It is when you try to export from the same input layer(s) in multiple threads that you get problems.

Thanks,

Mike
Global Mapper Guru
geohelp@bluemarblegeo.com
Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation

codemouse

OK - I am not on the latest SDK yet, but I will try a few things. Thanks!

Brian