OpenBridge Modeler

Create Terrain By Text Interpolation tool

Used to create a terrain model from 2D "tagged" contours and interpolating 2D linear elements and textual spots.

Found on the Civil ribbon in the Terrain Model group.



The Create Terrain Model by Text Level Interpolation tool utilizes 2D files. The linear data is derived by locating spot elevations on longitudinal MicroStation elements and interpolating. Contours must be "tagged" with the elevation, while break lines and voids use text at each vertex to determine elevation. Therefore, two sets of filters must be defined; one for the Linear Features and a second filter for the elevation information.

Tool Settings

SettingDescription
Append To Terrain If checked, select the exiting terrain model to append data to. Otherwise, a new terrain model is created.
Text Filter Allows selection of Graphical Filters' for the required text. To refine the filter use Graphical Filter Manager.
Linear Feature Filter Allows selection of Graphical Filters' for elements representing the text insertion point. A default text filter is supplied that looks at all text in the drawing to try and extract spot elevation is supplied. To refine the filter use Graphical Filter Manager.
Search Tolerance Used for linear features only - If the text justification is within the specified search tolerance of a vertex, then the elevation is included for TM creation for the linear feature. If the text is not within the search tolerance of any linear feature graphic, then the elevation is ignored for inclusion on any linear feature. However, it may be included as a generic spot elevation depending if it matches the graphical filter for spot elevations.
Note: Value is in master units.
Include Text as Spot Levels Check this box to look at all text in the drawing utilizing the justification point as the X,Y coordinates and the value of the text as the elevation and use as spot elevations.
Terrain Filter Manager Opens the Terrain Filter Manager dialog.
Preview Click to highlight any element in the view that matches the filter.
Triangulation Options group Several of the terrain model tools utilize the triangulation options section where the Edge Method is specified.

Many of the external edge triangles are thin and narrow and not representative of the surface. This is particularly evident where the edge of the data set is concave in nature. One approach to eliminate these triangles is the use of the Edge Method.

  • No Removal – No external triangles are deleted. Note the Maximum Triangle Length is ignored. There are no user defined parameters.
  • Remove Slivers – Long, thin triangles are dissolved based on a formula hard coded within the software. Note the Maximum Triangle Length is ignored. There are no user defined parameters.
  • Max Triangle Length – External triangles whose external edge is longer in length than the user specified distance are deleted. Note the option does not apply to internal triangles, only those on the edge of the model. Specify the Maximum Triangle Length in master units.
Feature Definition Select an existing feature definition from the drop-down list to use for object being placed.
Key-in: terrainmodel create byinterpolation