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### Settings

Map - Settings

On this page you can set the maps storage location and the map basic data.

Maps
  As loaction for the map data for Maemo (Nokia Internet Tablet) you should define a directory on one of the SD cards. With the help of the button Maps you can open a directory selection dialog and navigate to the SD card locations to find under /media/mmc[1|2]. In the text field beside the button you can see the current selection. You can modify the text field also by hand and set so your preferred location.
Projection
  The coordinate points of the raw maps Cumulus uses are not projected. They are coded according to WGS84 datum. Therefore all these points are projected on first loading. There are many types of map projections available. You need a projection because the earth is a sphere (or close to it) and your map is flat.
  Cumulus supports two projections:
  - Plate Carrée - Equidistant Cylindrical Projection
  - Lambert - Conical Orthomorphic Projection
  The first is computationally simpler and thus the preferred one in Cumulus. The latter is more complex, so your maps will take much longer on first load but it is more realistic.
  Each map projection needs a basis from where to work. For the Plate Carrée projection choose a parallel close to your home base. If the option Projection follows Home Position is activated, the parallel is automatically set to the latitude of your Home Position in the assumption that the Home Position is your preferred flight space. That ensures an unskewed map display and you are not forced to set this parallel by hand. That is the default setting.
  For Lambert projection you should select the parallels so that they are covering the area you are flying. For example, you could choose the parallels from your official flying map. Then you will have an equal look like these maps. You should select the longitude from the middle of the area you are flying. It is needed because of some technical reasons not for the projection itself. No automatic update of projection data is done here. You must do that always by hand. Therefore use this kind of projection only, if you are familiar with the Lambert projection.
  After changing the projection kind or the standard parallel values Cumulus is forced to recompile your map files. Please note that: If you don't set the projection options correctly, you will likely end up with a blue screen or a skewed map. This is especially so if you are far away from the coordinates used in the projection!
Map Management
  Cumulus supports two strategies for keeping maps in memory. Maps are only loaded if needed, but they can either stay there until they really need to be moved out of memory, or they can be removed sooner. The first strategy is more suited for users who want to zoom in and out a lot and have plenty of memory in their device, the latter strategy is the default one and to be recommended for people with lower memory devices.

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