Surface for Elevations

The user defines a three-dimensional surface file that GeoFluv™ will use as the reference surface from which the fluvial geomorphic surface will be designed. This surface file could be an existing Approximate Original Contour map, a pre-disturbance map, or any other surface from which the user wants to begin the design.

When the user clicks on the Surface for Elevations button, the Use Existing TIN or Create New TIN? Pop-up dialog box appears to give the user the options, by clicking on radio buttons, for entering a 3-D surface file. The user can type the file name into the File Name field or browse for the file by left-clicking the Browse button to the right of the File Name field. Left-clicking the browse button will open another dialog box that will display file selections and the directory path. The user can search for the surface file in various directories and left-click the Open button when the desired 3-D surface file is found.

When Open is clicked in the file search dialog box, the search dialog disappears and the Carlson Software 3D Viewer window will appear showing the .tin for the area that the user has defined. The user can rotate, fill in the .tin triangles, etc. to preview the .tin to be sure that it is satisfactory, i.e., no unwanted holes, elevation spikes, etc. When the user is satisfied that the .tin correctly represents the comparison surface, the user closes the 3D viewer window and the file name is entered into the File Name field in the Select Surface for Elevations TIN File - (tin;flt) dialog box, the file name appears below the Surface for Elevations button, details of the file loading will be listed on the command line: Loadings edges . . ., the number of points and triangles that were loaded will be listed. Regrade will also conduct an automatic save of the file and the path will be stated. The user is then ready to continue to Channels tab.

Alternatively, the user can click the radio button for Create new TIN file by selecting entities in the drawing. When the user selects this option and clicks OK, the cursor changes to a selection box that the user can use to define an area with a crossing window. (Note: it is very important that this area encompass the entire GeoFluv project .tin surface. If areas outside the GeoFluv boundary area may be used for material borrow and incorporated into the cut / fill balance, the .tin area should include those areas also.) After the user defines the .tin area and hits the enter key, the Carlson Software 3D Viewer window will appear as above. The remaining steps are also as described above.

When the Surface for Elevations file has been accepted, the file name is listed below the Surface for Elevations button, and GeoFluv™ reads the head and base level elevations from the Surface for Elevations file for the main channel that the user has sketched and displays these elevations in the "Data for main channel:" fields above the Surface for Elevations button. GeoFluv™ designs the main channel from this information and the settings on the Channels tab. The elevation at the heads of all other channels have their defaults set by the Surface for Elevations. The elevations along the GeoFluv Boundary are also set from this surface. This in turn sets the elevations of the main ridges and subridges and subridge valleys that intersect the GeoFluv Boundary.