[OSM-talk] GPS fun with Potlatch

[Richard Fairhurst]

I've just added some new GPX-mangling features to Potlatch. They're  
designed to be useful for people mapping long ways, almost certainly  
in rural areas.

If you choose a trace from the site's usual 'GPS traces' list, and  
click 'edit', then you'll be launched into Potlatch. The full trace  
will be shown with the usual light blue line, so you don't need to  
keep clicking the GPS icon. So far so good.

But you'll also see Potlatch has sprouted a few new buttons along the  
bottom when you first open it. One of these is 'Track'. Click it, and  
your GPS track will be magically turned into "locked" ways.

You can then edit the way as usual, splitting, deleting, tagging and  
merging to your heart's content. Because they're "locked" - you'll  
see a little padlock icon by the way id - Potlatch won't actually  
upload them until you unlock them. To do this, just click the  
padlock, then deselect the way as usual.

The clever (ish) bit is that Potlatch actually simplifies your GPS  
track when making it into ways (Douglas-Peucker algorithm), so you  
don't get eight zillion surplus points.

The not so clever bit is that it won't work with compressed traces  
(e.g. gzip). This includes any that you gzipped before uploading; and  
any old ones, because they're gzipped periodically to save space.

So to recap:

1. Find a newish GPS trace on the server.
2. Click 'edit' beside it to go into Potlatch.
3. Click 'Track' to turn it into nicely simplified ways.
4. Split, merge, tag, etc. etc.
5. For each way, click the padlock to unlock, then deselect the way  
to upload.

Oh, and there's a sandbox mode and a help link, too.

Enjoy!

cheers
Richard