[mkgmap-dev] Sharp angles in cycle ways

Tue Apr 8 09:16:34 BST 2014

Hi all,

a few days ago Felix suggested to add code to improve routing for bicycles:
http://gis.19327.n5.nabble.com/r3165-in-via-ways-branch-tp5802056p5802063.html

If I got that right, mkgmap should detect cases where two arcs meet at with a sharp angle 
and the arcs are only accessible by bicycle or foot. In such a case, mkgmap should
"manipulate" the angle so that the routing algo doesn't add too much time penalty,
as we can assume that the real angle is not that sharp.

Or mkgmap should assume that the created map is for cyclists only, so that car access
means something like racing bike.

Optimization would work like this:
1) at an y-shaped node, find the two arcs which are closer to a straight line and modify the 
initial heading of the other arc so that Garmin sees a right angle (90°)  .
2) at an x -shaped node, try to make all angles 90°
3) at nodes with more than 4 arcs, do nothing.

If the style adds multiple routable ways for one OSM way, the corresponding
multiple arcs between nodes on that way should be counted like one .

If that can be coded, it has only to be done if a new option like --optimize-cycle-ways is given.

Did I get that right? 

@Felix:
Please provide a test case (the OSM id of a node ) 

Gerd

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.mkgmap.org.uk/pipermail/mkgmap-dev/attachments/20140408/31a8a2e3/attachment.html>