2009

When positioning a model relative to sea level, the height of the Google Earth reference points
must also be measured relative to sea level. When positioning a model relative to the ground, the
Google Earth reference points must be measured relative to the ground.
Google Earth always places new placemarks at an altitude of zero, irrespective of whether that is
relative or absolute.
3. Collapse on export allows different levels of collapsing parts of the model hierarchy in the exported
file.
• None ensures the whole heirarchy is exported
• All objects collapses everything into one node
• Files collapses each file into one node
• Layers collapses each layer into one node
4. Limit number of Polygons should be enabled to restrict the amount of geometry exported into the
output file. Geometry is selected on the basis of taking the most obvious objects in preference to the
fine detail. If the exported file is too large for Google Earth to display, try enabling this and reducing
the number of polygons. View, Scene Statistics in NavisWorks shows the number of triangles
and/or lines in the current project. By setting a polygon limit you are choosing to export only some of
these items.
Note:
Google Earth's ability to handle large numbers of polygons is far more limited than NavisWorks.
Hence it is worth noting that currently Google Earth will consider 1,000,000 polygons as being a
big model.
5. The Origin position values are the first pair of reference points on the Google Earth surface, and
must always be defined. The NavisWorks reference point will always be positioned to exactly overlay
the Google Earth reference point.
Second and Third reference points can be used, and if enabled then the position and orientation of
the model can be more accurately defined.
6. Use the Import buttons to read-in saved placemark locations from KML files exported from Google
Earth.
The Origin Import button differs slightly from the other two; if the KML file contains multiple
placemarks, this button will offer the user the choice of importing second and third reference points if
available. The other two buttons will only import a single reference point.
7. The Pick buttons allow the reference point locations to be selected in the main 3D view.
These points must be visible in the main 3D view prior to exporting, as once the KML Options dialog
box is open you will not be able to navigate before picking.
Note:
You may wish to use View, Split to split the main 3D view enabling you to have separate views of
each reference point.
File Management
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