| MAPC2MAPC Help pages : Working with SQLITE files |
|||||||
|
SQLITE is a form of database that uses SQL commands to access it. This page is an explanation of their use for slippy map tiles. These are map tiles that are 256 pixels square; they use a Spherical Mercator projection and tiles are indexed by X, Y and Z. Z is the zoom level - there are 2^Z tiles around the earth counted from 180 degrees. X and Y are the tile numbers counted east and south from a point north of the Bering Strait. But you don't need to know this to work with them. Maps in this format can be used by various apps for mobile devices : Locus, BackCountryNavigator and Maverick for Android; GalileoGPS and MapPlus for iOS. MAPC2MAPC will open a SQLITE database and display the map. Change zoom levels with the mouse wheel and use the mouse to drag the map around. If you have loaded (or drawn) maps with Track Manager then these will be displayed. In this state the program is working with a window onto an endless map. To do further processing - printing, converting for a mobile app, etc - an area of the map needs to be extracted. To do this, zoom to the level you want then use CTRL+Click. If any tracks are loaded the program will extract a rectangle to cover all the tracks; otherwise it will extract a square around the current mouse position. There is a dialogue to set the size of the square. Once extracted it can, of course, be cropped by the program ase necessary. SQLITE files can also be processed by Mobile Atlas Creator (MOBAC). To do this the program has to be made aware of them by placing a descriptive file in the Mapsources folder of MOBAC. This is an XML file : copy the lines below and load them into an editor such as Notepad. Change the name (which is what will appear in MOBAC) and specify the path to the file. Then save this in the Mapsources folder as, for example, north.xml. <?xml version="1.0" encoding="UTF-8"?> <localTileSQLite> <!-- Map source name as it appears in the map sources list. --> <name>north opendata</name> <!-- File path to SQLite atlas file --> <sourceFile>c:\users\john\north.sqlitedb</sourceFile> <atlasType>RMaps</atlasType> <backgroundColor>#000000</backgroundColor> <tileImageType>PNG</tileImageType> </localTileSQLite> |
||||||