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Importing Bitmaps from GoogleMaps

CadnaA offers the possibility of importing geo-referenced bitmaps from GoogleMaps. There are two procedures on how to import bitmaps from GoogleMaps:

  1. The location of the CadnaA objects or the bitmap object is known with respect to a geodetic coordinate system. In this case bitmaps can be imported in correct position from GoogleMaps.

  2. The location of the CadnaA objects is not geo-referenced (i.e. only relative local coordinates are known). In this case bitmaps can be imported by selecting the area in GoogleMaps.

Objects Coordinates are geo-referenced

In case the object coordinates are in a known geodetic system proceed as follows:

  • If the geodetic datum of the object coordinates is known open the dialog Coordinate System (Options menu).
  • On the dialog Coordinate System select the corresponding system and the reference point and click OK. Alternatively, enter the EPSG code.
  • Select the bitmap symbol from the toolbox and draw a frame at the position where you would like to have the bitmap inserted.
  • Click in the edit mode with the right mouse button on the border of the bitmap.
  • On the dialog Bitmap click the button „Google Maps“.
  • Activate on dialog Options for GoogleMaps import the option "Use Bitmap-Dimensions“.

Option „Use Bitmap-Dimensions“ activated

  • The „Zioom Level“ determines the resolution and also the file size of the imported file. Keep the default settings for now.
  • Agree with the conditions of use of GoogleMaps and click OK.

The browser as set on your system is launched and the bitmap file downloaded immediately.

  • Enter a file name and save the file to your drive.

Subsequently, the downloaded bitmap is displayed in CadnaA. In case the resolution is too low, repeat the procedure using higher detail settings.

Note

By default, the display mode „Satellite“ is used in GoogleMaps.

Bitmap as background image, imported from GoogleMaps

Bitmap as ground texture in 3D-Special view

Objects Coordinates are not geo-referenced

In the alternative case the bitmaps can be imported by selection in GoogleMaps.

  • If necessary select the command New from the File menu.
  • Select the bitmap symbol from the toolbox once more and draw a bitmap frame.
  • Click in input mode with the right mouse button on the border of the bitmap (alternatively, double-click with the left mouse button in edit mode).
  • On the dialog Bitmap click the button „Google Maps“.
  • Activate the option "Choose region in browser“ on dialog Options for GoogleMaps.

Note

With the option „Initial position on the bitmap center“ activated the bitmap will be centered on the bitmap frame.

Option „Choose region in browser“ activated

  • Agree with the conditions of use of GoogleMaps by activating the check-box and click OK.
  • On the subsequent dialog Coordinate System select the system to be applied for the corner coordinates of the bitmap.
  • For example, select the system „UTM coordinates (northern hemisphere)“ with the reference „WGS84“ and click OK.
  • Now, CadnaA switches to GoogleMaps in your browser to select a region.

The red rectangle includes the section to be imported. The rectangle can be moved with the mouse and reduced or enlarged by its corners. Further, the following buttons are available:

  1. "Visible Area" area: Here you can enter latitude/longitude (Lat/Lon) of the rectangle‘s center. By clicking with the mouse outside of the box the new values ​​are adopted.

  2. "New Selection" button: A dialog is opened in which the latitude/longitude can be entered (alternatively to the input in "Visible Area").

  3. "Center selection" button: After moving the map in GoogleMaps, clicking this button will move the red rectangle to the current location and center on it.

  4. "Pan to Selection" button: If the map has been moved in Google Maps, clicking this button will center on the existing red rectangle.

  5. "Export" button: The browser window is closed and the current selection is exported as a bitmap file (opening „Save as“ dialog).

In the upper left corner of the Import from Google Maps dialog, the display style to be used for the bitmap import can be selected (RoadMap, Satellite, Terrain or Hybrid).

  • Select the required region using the features provided by GoogleMaps.
  • When the location has been set click the „Export“ button to export and save the bitmap.

In case the bitmap coordinates are outside the present limits, they can be adjusted automatically. The imported bitmap is displayed in CadnaA with the object coordinates according to the selected geodetic datum.