The navigation map window displays a list of raster maps as a 2D reference to the 3D world. The ITENavigationMap5 and _ITENavigationMapEvents5 interfaces allow setting and interacting with the window and maps. The interface can reference a navigation map window in TerraExplorer standard GUI or be created as an ActiveX control.
See: “Navigation Map Window” chapter in the TerraExplorer User Manual.
Add Maps to the Navigation Window
The definition and setting of various map source files and settings is defined in an XML standard. Use ITENavigationMap5:: LoadXML to add maps to the window. A minimal information set must be included in the XML string that is passed as a parameter. You can use the XML string for window persistence window.
The XML string should be in the following format (bold fields are mandatory for CreateLayer):
<NavigationMapControl >
<Projection>
<Group></Group>
<System></System>
<Datum></Datum>
<Unit></Unit>
</Projection>
<Map>
<Description> </Description>
<Source PlugName=""> </Source>
<Corners Left="" Top="" Right="" Bottom=""/>
<TiePoints>
<TiePoint MapX="" MapY="" TerrainX="" TerrainY=""/>
</TiePoints>
<Projection Reproject="" >
<Group></Group>
<System></System>
<Datum></Datum>
<Unit></Unit>
</Projection>
</Map>
</NavigationMapControl>
Parameters
§ Projection – The window projection. Any map that is marked for reprojection is reprojected to this projection. If not defined, the values are automatically added to the XML based on the terrain database projection.
· Group – Defines the window projection group.
· System – Defines the window projection system.
· Datum – Defines the window projection datum.
· Unit – Defines the window projection units
§ Map –Each “Map” node represents a map in the window.
· Description – The name of the map as it appears in the map selector drop-down menu.
· Source – A full path name or a URL to the map source.
· Attribute: PlugName – The name of the plug-in that reads the file, e.g., “tifplg.rct“. The available plugins are files with an RCT extension which are located in the “TBPlugs” directory. If an empty string is passed into this parameter, the default plugin for the file type is used.
· Corners – Geo-referencing information for the map bounding coordinates (You can use TiePoints node instead of this node):
Attribute: Left – The leftmost X-coordinate.
Attribute: Top – The topmost Y-coordinate.
Attribute: Right – The rightmost X-coordinate.
Attribute: Bottom – The bottommost Y-coordinate.
· TiePoints – The Geo-referencing information is defined by exactly three pairs of TiePoint nodes (You can use Corners nodes instead of TiePoint nodes).
TiePoint – Coordinates of paired map and terrain tie-points:
Attribute: MapX – West-East coordinate in map pixels.
Attribute: MapY – North-South coordinate in map pixels.
Attribute: TerrainX – West-East coordinate in MPT units.
Attribute: TerrainY – North-South coordinate in MPT units.
· Projection – The source projection. If the Reproject attribute is set to 1 the source is projected from this projection to the map window projection.
Attribute: Reproject – Use 1 to reproject the source, 0 to leave as is.
Group – Defines the source projection group.
System – Defines the source projection system.
Datum – Defines the source projection datum.
Unit – Defines the source projection units.
Reference a map to the terrain database
There are four ways to reference a map to the terrain database:
§ Geo-Referenced Source – If the source file or server includes geo-referencing information, this information is automatically read and used. If the map is referenced to a different projection than the projection used for the navigation map window, you can use the Reproject option in the XML map definition.
§ Corners Node – Add a Corners node to the XML Map node containing referencing information in the form of Top-Left and Bottom-Right coordinates.
§ TiePoints Node – Add a TiePoints node to the XML Map node containing referencing information in the form of three pairs of matching terrain and map coordinates.
§ SetMapTiePoint and SetTerrainTiePoint – Use the SetMapTiePoint and SetTerrainTiePoint methods to provide three pairs of matching terrain and map coordinates.