Some building walls are invisible when extrusion zoom-min < 15

[wolfgang-ch]

When the zoom-min value is below 15 then the building walls on some buildings are invisible

zoom-min=14

zoom-min=15

[devemux86]

What platform?
What graphics card and driver?

What map source?

Please test with VTM samples where everyone can try to reproduce the report.

You can try without shadows (default)
and see if it works better with your graphics card.

[wolfgang-ch]

[LWJGL Application] INFO org.oscim.gdx.GdxMap - Type: OpenGL
Version: 4:6:0
Vendor: NVIDIA Corporation
Renderer: Quadro T1000/PCIe/SSE2

Platform : Windows 10
Map source : Mapilion
Theme : OpenMapTiles (with modified zoom-min value in /vtm-themes/resources/assets/vtm/openmaptiles.xml)

You can try without shadows (default)

Without shadow it do not look better

It also depends on the tile, some tiles are OK some not

Please test with VTM samples where everyone can try to reproduce the report.

I need to prepare the samples

[devemux86]

MapilionMvtTest on Linux seems to work correctly.

It is recommended to use the default building min zoom level 17.
We do not know at what zoom map providers have building data.

And also try Mapsforge offline maps.

mMap.layers().add(new BuildingLayer(mMap, l, 15, mMap.viewport().getMaxZoomLevel(), false, false));

[wolfgang-ch]

New York: When using the zoom level ... 17, 16 and 15 then buildings are OK but with 14 some tiles are not OK

Zoomlevel 15

Zoomlevel 14

Bremen: Zoomlevels 14 and 15 are OK

Zoomlevel 15

Zoomlevel 14

Paris: Looks more ugli with zoomlevel 14

Zoomlevel 15

Zoomlevel 14

[wolfgang-ch]

Mapsforge has the same issues on zoomlevel 14

[devemux86]

It is recommended to use the default building min zoom level 17.

tag-mapping has zoom-appear="17" for the building extrusions.

[wolfgang-ch]

I would like to allow the user to set the min zoom level for buildings to the zoom levels 16 + 15 which are working very smoothly without any issues.

To do this, the zoom field in

vtm/vtm/src/org/oscim/theme/rule/Rule.java

Line 55 in 4fb99aa

public final int zoom;

needs to be set, but currently it is final.

I could create a test code successfully with a RuleVisitor to set this field in my dev environment.

I would like to create a PR which can set this zoom field and it is removing the final keyword.

Would you accept such a PR?
When not, which solution would you suggest?

[devemux86]

See above, the theme and BuildingLayer should work.

[wolfgang-ch]

Now I'm going the hardcore way...

...and it works perfectly