Ghostlines while rendering contourlines and bbox-enlargement

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Christian Kernbeis

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Apr 19, 2012, 3:21:17 AM4/19/12
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I have problems with ghost-lines while creating or rendering contourlines at Level 12 + 13.

I seems that the problem occours at the border of the tiles, so I tested an area where nothing else exists
with different settings of bbox-enlargement [0,20,40].

With bbox-enlargement=0 its clear to see that ghostlines occour ot the border of the tiles and
with this setting over all zoom-levels.
With bbox-enlargement=20 or 40 the ghostlines disappear at level 14+

No idea if this is an issue of the map-writer or renderer.

It would be great if this issue could be solved, mapsforge has an enormous potential to create topo-maps and overcome Mobac
even on 32bit Windows equipment AND it's incedible how easy the appearence of the map can be changed even to create
a user friendly map of Iceland.

I include the map/osm/xlm's and script for the Herdubreid-area on Iceland.

best regards
Christian

iceland.zip

jurajs

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May 7, 2012, 6:00:32 PM5/7/12
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Hi Christian,

try to use force-polygon-line="true"

e.g.:

    <osm-tag key="contour_ext" value="elevation_minor" zoom-appear="12" force-polygon-line="true" />
    <osm-tag key="contour_ext" value="elevation_medium" zoom-appear="12" force-polygon-line="true" />
    <osm-tag key="contour_ext" value="elevation_major" zoom-appear="12" force-polygon-line="true" />


results are much better.
j.

Christian Kernbeis

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May 8, 2012, 7:20:16 AM5/8/12
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Hello,

Thanks a lot, the results are close to perfect, only some pixel overlaying appears with the dotted lines at the borders of the tiles ;-)))
OK this means re-rendering of all my maps - perfect for testing my new SSD.

best regards
Christian

jurajs

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May 8, 2012, 5:45:55 PM5/8/12
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ssd is fine(i have one). but you can trust me -> bottleneck is cpu ;-)

btw: http://forum.asamm.cz/viewtopic.php?f=43&t=1839

Christian Kernbeis

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May 9, 2012, 2:22:58 AM5/9/12
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Hello Jurajs,

Its fine that you released the contour maps to the public for free, it will give mapsforge a boost.

Once Thilo resolves some minor rendering problems like rendering cycle-nodes in the netherlands (thats not very reliable but works for 90%)
we will overcome all those stupid issues with licences that prevent me from using my legally bought maps on my android device....

Next development in the pipeline are cycle-maps, up to now I spent >250hours in serious perl-coding to preprocess OSM-Data to be
compatible with the possibilitys of the mapsforge-mapwriter (resolving cycle+mtb relations incl. NL/BE cycle nodes).
The maps look VERY similar to Andy Allens OpenCycleMaps, the only issue is that I have to speed up the perl code because
resolving the Netherlands (worst case for making cycle maps) dataset needs >90hours - the whole OSM Database have to be analysed and completely rewritten......

best regards
Christian



Am Dienstag, 8. Mai 2012 23:45:55 UTC+2 schrieb jurajs:

ssd is fine(i have one). but you can trust me -> bottleneck is cpu ;-)

btw: http://forum.asamm.cz/viewtopic.php?f=43&t=1839


Am Dienstag, 8. Mai 2012 23:45:55 UTC+2 schrieb jurajs:

ssd is fine(i have one). but you can trust me -> bottleneck is cpu ;-)

btw: http://forum.asamm.cz/viewtopic.php?f=43&t=1839


Am Dienstag, 8. Mai 2012 23:45:55 UTC+2 schrieb jurajs:

ssd is fine(i have one). but you can trust me -> bottleneck is cpu ;-)

btw: http://forum.asamm.cz/viewtopic.php?f=43&t=1839


voldy

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Jan 2, 2013, 4:43:34 AM1/2/13
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Hello,

Firstly I have to thank you because your advices here or at locus forum about creating contour-lines were very helpful for me.

At these days I try to improve contour-lines and for this reason I have following question:
Is there any way how to obtain “perfect” contourlines without overlaying pixels?
I’ve tried to change bbox-enlargement but the lower value caused wrong rendering of areas (woods, industrial areas and so on) for zoom-levels 12-13. I guess that bbox-enlargement=15 could be balanced value. 

So, did you try to change bbox-enlargement value or do you use default value? Or is there any possibility how to avoid overlaying pixels for contourlines?

Thank you 
Regards Petr

Christian Kernbeis

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Jan 4, 2013, 9:06:38 AM1/4/13
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Hi,

I use a bbox-enlargement of 5, however, it doesnt change that much..

Regards
Christian
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