Understanding Profiles |
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The vertical alignment data is represented by two collections: the EGProfiles and the FGProfiles. The EGProfile, or existing ground profiles, contains the sampled surface data along the alignment. The FGProfile, or finished ground vertical alignments, contain the PVIs which represent the basis for the final roadway design. The EGProfile can be imported into the drawing, so that the finished vertical design data can be drafted onto the ProfileBlock.
Existing Ground Profiles
While the ActiveX interface does not require you to define any EGProfiles, the vertical alignment editor expects the Existing Ground Center to be defined.
Finished Ground Profiles
When you create a new FGProfile object, a default PVI is added to the PVIs collection as a place holder. The properties of this PVI are all set to 0.0. This behavior is intentional since at least one datum is required to access the vertical alignment editor.
It is up to the user to make sure that the geometry for the Finished Ground Profile is correct. When defining a profile, be sure to check for the following:
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A Finished Ground Profile cannot support a vertical curve on the first or last PVI.
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The Finished Ground Profile object does not check for overlapping vertical curves.
- The Finished Ground Profile object does not check to ensure the start and end points coincide with the paln alignment.
Locking
Existing Ground Profiles and Finished Ground Profiles objects use the same locking as the Alignment. If the Alignment has a read lock, then Existing Ground Profiles and Finished Ground Profiles have a read lock. The same is true for write locks. Remember, the only way to generate a write lock is to set the Alignments.CurrentAlignment to the one you want to work with.
ProfileBlocks
ProfileBlocks do not support xrefs. If an drawing is XRefed into another drawing and it has a profile, the ProfileBlocks collection will not put it into its list.
In a drawing, an alignment can have more than one ProfileBlock drawn. If this happens, there will be no unique identifier for the ProfileBlock. The ProfileBlocks collection will have both ProfileBlock objects but it is up the user to determine which profile will be used.
The scale factor used for the vertical exaggeration of the existing ground and finished ground profiles is the ProfileBlock.VerticalScale divided by the DatabasePreferences.DatabaseScale.
The Coordinates of the ProfileBlock are one inch below the DatumElevation baseline.