[mkgmap-dev] Map display squeezed horizontally

Sun Apr 21 13:38:49 BST 2013

Felix Hartmann schrieb:

> The actual reason for this problem is, that Mapsource >=6.14 and
> Basecamp cache the map before/while you view it. Therefore it needs to
> fix the projections. Hence - the more out of the center of the map you
> move (south/north), the more distorted it will be. Moving east/west of
> course doesn't create distortion.

Thank you Felix, now it's clear. I had confused "projection angle" with 
"viewing angle" (the angle at which a viewer is looking to the map, 
caused by a tilt of the map).

If the projection angle is the latitude for which the correct horizontal 
width of the map display is calculated, it is clear that areas north of 
this latitude get stretched, while areas south of it are shown squeezed.

Although I am creating a map for Germany, there are some huge but almost 
empty tiles up to N 60°. One of them covers the whole area between 
Berlin and Helsinki, others are far out on the Atlantic Ocean, west of 
Scottland. If Mapsource automatically selects an projection angle in the 
middle between the points with the max. and the min. latitude, this will 
result in a projectoion angle of more than 50° for my map and so almost 
the whole area of Germany appears to be squeezed.

Is there an easy way to remove these tiles from the map (I think they 
only contain ferry lines, pipelines etc.) without using
--keep-complete=false for the splitter and without causing artifacts by 
cutting the contour lines (they are merged to the OSM data before 
splitting)?

Thank you,

Michael