Artefacts (vertcal and horizontal lines) when using contour lines

[Martin Vennekamp]

Hi,

first of all: I upgraded my Project to the 0.61 release of Mapsforge and, as always, it works pretty well.

Additionally and Independent from the mapsforge version I started to Play with contour lines using this tutorial:

http://oruxmaps.forosactivos.net/t2216-contourlines-added-for-oruxmapsforge#8944 

It also works quite well, but I see some 'extra drawn crosses' in the style of the contour lines, as also visible on the first screenshot in the tutorial. (above the "%" of the "100%")

==> Is there a way to get rid of these "crosses of contour lines"?

Regards,

Martin

[Emux]

On 24/06/2016 04:31 μμ, Martin Vennekamp wrote:

first of all: I upgraded my Project to the 0.61 release of Mapsforge and, as always, it works pretty well.

Nice, thanks for the feedback!

Regarding tile border artifacts at some zoom levels, that's an old issue, you can read details about it here.

Solving it could work in render themes for affected areas, by not using stroke, instead only fill.

But the best solution I have found so far is during map creation, to use a different zoom interval:
zoom-interval-conf=5,0,7,10,8,11,12,12,13,14,14,21

--
Emux

[fzk]

Please provide a screenshot of the problem.

Klaus

[Martin Vennekamp]

Hi Klaus,

a screenshot is linked in the tutorial (see my first post)

I could solve the problem using the "best solution", but the map-file is now larger:

7,00 MB vs. 8,95 MB with zoom-interval-conf=5,0,7,10,8,11,12,12,13,14,14,21

The original map without contour lines had a size of 4,58 MB.

Thanks for the help and Regards, Martin

[Karsten T.]

hello,

the problem is still there in 0.15 and changing zoom-interval-conf didn't solve the problem for me, it also didn't affect contour-lines only.

in my case i had an area with a line style which caused the problems. since i didn't need to fill the area i converted it to a line and split the line node-based, to have multiple lines with less than 1000 nodes instead of one line with thousands of nodes. converting this file instead of the area fixed the problem for me.

i hope this tip helps someone who faces the same issue and can't fix it by changing the zoom level

[Emux]

(I don't know which map library you mean, Mapsforge or VTM)


There are related discussions with hints in OpenAndroMaps (here and here):

- Map writer documentation mentions a different zoom-interval-conf

- Use force-polygon-line option in tag-mapping

--
Emux

[Karsten T.]

(I don't know which map library you mean, Mapsforge or VTM)

i'm using vtm but according to the threads it's a map-writer issue, which should affect both mapsforge and vtm?

 

There are related discussions with hints in OpenAndroMaps (here and here):

these discussions did help, but i still don't understand why there are only issues at zoom intervals smaller than 14 - probably the default zoom-interval-conf could be tweaked?

 

- Map writer documentation mentions a different zoom-interval-conf

i tried that and the issues were smaller but still existing

 

- Use force-polygon-line option in tag-mapping

this seems to be the best option  - i couldn't find this in the map writer documentation - is there a reason this is not listed? i was looking under known pitfalls and the grid artifacts are mentioned but not the force-polygon-line workaround

[Emux]

I updated the documentation.

--
Emux