Creating the Site Model

Creating a Site Model from the Source Data

Once source data has been obtained for the site model, the site model can be created.

To create a site model from source data:

1.	Ensure that valid source data exists. The site model can be created from 3D loci, 3D polygons, stake objects, or by one of the methods described in Site Model Source Data. Verify that there are no problems with the source data with the Validate 3D Data command (see Validating 3D Source Data).

2.	Select the source data.

3.	Select Landmark > Create Site Model (Landmark workspace) or AEC > Terrain > Create Site Model (Architect workspace).

The Create Site Model dialog box opens. Specify the site model settings.

 

Parameter	Description
Site Model Name	Enter a name for the site model object
Keep Original Source Data in Layer	Leaves a copy of the source data in the layer (the site model always retains a copy of the source data in its profile group). This parameter displays only during initial site model creation.
Settings
Minor Contour Interval	Specifies the standard contour line placement interval
Major Contour Multiple	Specifies the placement interval of major (heavy) contour lines
Start Contour Offset	Indicates the creation offset for the first contour line. The contours are measured from this point. (Usually this number is 0; entering an odd value allows contour intervals to be set with odd numbers)
Maximum Elevation	Specifies the highest contour elevation to be displayed. No contours are created if the maximum elevation is lower than the minimum elevation, but this can be useful for cut and fill calculations (for example, for pond or backfill volumes).
Minimum Elevation	Specifies the lowest contour elevation to be displayed
Datum Elevation	Indicates the reference elevation used to define the bottom of a site model when the 3D Mesh Solid style is selected in 3D Display Settings; set to zero for normal cut and fill calculations
Flow Arrow Spacing	Determines the placement of the flow arrows
3D Grid Spacing	Sets the grid (mesh) size; also determines flow arrow placement
Smoothing Interval	When selecting a triangulation method for 2D and/or 3D site model display, sets the distance for adding new points to the contours. Enter zero to use the original contour points for triangulation. Entering a value that is too low may result in long calculation times.
2D Display Settings
Display	Select whether to display the existing site model only, proposed site model only, or both existing and proposed site models. The display option can be changed later from the Object Info palette.
Existing Only	Displays only the current model
Proposed Only	Displays only the proposed model (the current model changed by any site modifiers)
Proposed + Existing	Displays both the proposed model and the existing model; this option is useful when using the site model for a grading plan, with different existing and proposed topographical line styles
Style	Select a 2D DTM display mode
2D Contour	Draws contour lines
2D Contour (smoothed)	Smooths contour lines
2D Contour (colored elevations)	Draws contour lines and colors the elevations for conducting an elevation analysis (elevation analysis parameters are specified by clicking Graphic Properties and selecting the Site Analysis tab; see Setting Site Model Graphic Properties)
2D Triangle	Represents the surface as triangular facets
2D Triangle (colored slopes)	For 2D triangle display, colors the slopes within specified angle ranges for conducting a slope analysis (slope analysis parameters are specified by clicking Graphic Properties and selecting the Site Analysis tab; see Setting Site Model Graphic Properties)
2D Triangulated Contours	Draws 2D contour lines by triangulation, according to the specified Smoothing Interval
2D Triangulated Contours (colored slopes)	Draws 2D contour lines by triangulation, according to the specified Smoothing Interval, and colors the slopes within specified angle ranges for conducting a slope analysis
Show Flow arrows	Adds arrows to show the downward direction for drainage analysis
Show Labels	Labels major 2D contour line elevations
Parallel to the topo line	When labels are selected for display, labels are parallel to the topography lines
Draw Hull	Draws a closed 2D polygon along the hull (outer edge) of the DTM
3D Display Settings
Display	Select the 3D site model display. The display option can be changed later from the Object Info palette.
No 3D Display	Displays only the 2D site model, with no 3D component
Existing Only	Displays the existing 3D site model
Proposed Only	Displays the proposed 3D site model
Style	Select a 3D DTM display mode
3D Contour	Draws the DTM using horizontal 3D polygons
3D Grid	Draws the DTM using a regular grid (mesh) of squares (closed 3D polygons); allows the mesh to be colored, filled, and rendered with shadows
3D Mesh solid	Groups 3D triangles to form a VectorWorks mesh; a skirt and bottom are added to create a valid solid
3D Triangle	Generates 3D triangles with the Triangulated Irregular Network (TIN) method; this method is the most accurate, as it involves no interpolation
3D Triangles (colored slopes)	Generates 3D triangles with the Triangulated Irregular Network (TIN) method, and colors the slopes within specified angle ranges for conducting a slope analysis
3D Extruded Contour	Creates horizontal solids with a thickness equal to the contour interval; top edges run along contour lines or the hull. This creates a “layer cake” or “chipboard model” effect.
3D Triangulated Contours	Draws 3D contour lines by triangulation, according to the specified Smoothing Interval
3D Triangulated Contours (colored slopes)	Draws 3D contour lines by triangulation, according to the specified Smoothing Interval, and colors the slopes within specified angle ranges for conducting a slope analysis
Show 3D Grid	Superimposes a 3D grid on the model; specify the grid spacing value in Spacing
Fill	Displays 3D grid squares with a fill; Show 3D Grid does not need to be selected to display a filled grid
Show 3D Contour	Superimposes a 3D contour on the model
Use Site Modifiers on
All Layers	Modifies the proposed site model with modifiers from any layer in the file
Same Layer as Site Model only	Modifies the proposed site model with modifiers that exist only on the site model layer
Graphic Properties	Specifies the DTM appearance, along with slope and elevation analysis parameters (see Setting Site Model Graphic Properties)

4.

Click OK.

A site model is created in the active layer and displays as specified.