[OSM-talk] Josm: bug in Simplify Way?

Gabriel Ebner ge at gabrielebner.at
Tue Jul 15 23:54:32 BST 2008

On Mon, Jul 14, 2008 at 11:26:39PM +0200, Niccolo Rigacci wrote:
> > Don't rely on automated simplifiers for conversion of GPS data, do it by hand.
> Why not?
> I suppose the algorithm is well known and definited: nodes should 
> be removed only if the semplified way does not diverge by a 
> predefinite amount.

The simplify way action uses the Douglas-Peucker algorithm.  You can change
its tolerance (in meters) by modifying the "simplify-way.max-error" preference
(go to the preferences tab, click on the Einstein face, and click "Add").

Only nodes that are within the tolerance of the simplified way are removed.
Nodes that are used by other ways or relations are not removed either.

By default it uses a tolerance of 50 meters, so if you want less points to be
removed, you might want to set this to, say, 10 meters.

Hope this helps,

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