Enable application to set min and max zoom levels

[mapsforge]

From LudwigBr...@gmail.com on February 12, 2011 09:42:18

I think it would be beneficial to add api functions to allow the app to set its own maximum and minimum zoom levels for the map. Currently, if I understand it correctly, the max zoom level is set through the map file generated and it is not possible to set a minimum zoom level. But as most mapfiles will be an extract they will not look very good at low zoom levels.

I have attached a patch to the current head (version 0.2.1) that allows the app to set the zoom levels and which plays nicely with the zoom controls in the mapviewer.

Attachment: minzoom.patch

Original issue: http://code.google.com/p/mapsforge/issues/detail?id=79

[mapsforge]

From thilo.mu...@gmail.com on February 12, 2011 07:30:14

Thank you for your suggestion. Your patch seems to miss a few cases and doesn't follow our code conventions completely, but anyway it is a good start. I will add this feature to the map library soon so that it will be part of the next release.

Status: Accepted
Owner: muehlb...@inf.fu-berlin.de
Labels: -Type-Defect Type-Enhancement

[mapsforge]

From thilo.mu...@gmail.com on February 20, 2011 04:16:31

In revision r829 i have added a method to set the minimum zoom level for the MapView.

Setting the maximum zoom level is more complex, as the highest possible zoom level depends on the current MapViewMode and is therefore not static. For example, in downloading mode the maximum zoom level may be 17 (Osmarender) or 18 (Mapnik) while in offline rendering mode the maximum zoom level is currently set to 21.

Is there really a need to restrict the maximum zoom level? If not, we can mark this issues as fixed.

Status: Started

[mapsforge]

From LudwigBr...@gmail.com on March 06, 2011 02:09:34

Just had a chance to look at this now. The code is fine and it is probably not essential to have a max zoom level in the code.
However, is it possible to set the max zoom level for offline rendering somewhere when creating the map file? I personally find that beyond zoom level 18 the map does not improve any more and certain irregularities of OSM maps really begin to show (e.g. lines not straight or parallel, angles of rectangular buildings usually not at 90deg etc.), so I like to suppress the user's ability to zoom in further.

[mapsforge]

From thilo.mu...@gmail.com on March 25, 2011 10:22:35

In revision r981 i have added a method to set the maximum zoom level for the MapView.

You can now use the setZoomMax(byte) method to control how far the user may zoom in. If you set a higher value than the currently selected MapViewMode supports, the limit will have no effect of course.

I will mark this issue as closed now as all requested features have been implemented.

Status: Fixed