[mkgmap-dev] Re: [PATCH] Creating contour lines from DEM data

Sat Jul 4 09:04:15 BST 2009

0> In article <68B4C1B8-4426-4453-8B09-00B90F870F01 at gmx.de>,
0> Thilo Hannemann <URL:mailto:thannema at gmx.de> ("Thilo") wrote:

Thilo> So especially with your solution to integrate the contour lines
Thilo> into the map this is IMHO a derivative work, so that all components
Thilo> of it must be subject to the OSM license.

Agreed.  I believe (but I'm not any kind of lawyer!).

I'd say that separate invocations of mkgmap (one with OSM data and one
with contour data) would be fine - it's perfectly possible for a user to
then combine them into a single gmapsupp for their device.

In fact, separate maps is probably also the best plan for those of us
generating maps for our own use (and not distributing them), as the
contour maps should be a one-shot task.

Things would get complicated if the contour generation algorithm uses
water body data to discover flat regions, though.

P.S. it would be interesting to see contour regions (as opposed to lines)
suitable for elevation shading layers; another idea is to compute slope
aspect for a hill shading layer - maybe I'll look into that when I get
time...