Civil Design Suite for TurboCAD

Surface Modeling

Triangular Irregular Network (TIN) creation

Most of the functionality of Surface Modeling require a TIN surface to be active. To create one simply select your data and press the “Create Triangles” button.

Arc Error is the maximum error when converting arcs to strait line segments.

Triangular irregular network editing


See how it works:



Soft break lines

Single line in the data used to create a TIN will be considered soft break lines. Its’ segments will be triangle edges.



Hard break lines

Double lines are soft break lines but when selected with a TIN for the creation of a TC surface or solid will be used to control the calculation of normal.



Create a TurboCAD surface from a TIN

To create a surface your must have either a set of point and/or lines selected. Or you must have a triangulation active. The following dialog allows you to select whether the result is a set triangles or a triangulated grid.


If you have only point data selected then this dialog allows you to select an interpolation method. Bivariate spline is used for all surface modeling interpolation.




Create a TurboCAD solid from a TIN



Create points at a location with z value interpolated from the TIN

With a TIN active clicking anywhere on it will produce a point.



Slope down angle and direction at any point on TIN

With a TIN active clicking anywhere on it will produce the arrow and value.


Flow lines

With a TIN active clicking anywhere on it will produce a line starting at that point. The length of the line is controled in settings.



TIN surface cross-section along a line

A TIN must be active.



TIN surface profile along a polyline

·         Station interval distance

·         Plan view

·         Save data to clipboard

·         Save simple graph to clipboard


Have an atcive TIN and polygon selected.



This is what the Plan View looks like:

Notice that horizontal curves are labeled.



Here is an example of a the graph that goes onto the clipboard:


Creates contours, major and minor

Contour lines are based on the interpolation surface. Levels are labeled with the “Contour Label” tool.

·         Divide Range When the “divide range” option is selected the difference between the maximum and minimum elevation is divided by the value specified by “Number of levels”.

·         From Datum When “From Datum” is selected the value of “Datum” will be a contour level. It need not be in the data range. The default value of this datum is the average elevation value. Then subsequent contour levels are above and below the datum the distance you set in “Interval.”

·         Segment Length The “segment length” determines the accuracy of the iteration as well as the number of points of the contour line. As this number gets small the contour line approaches a continuous curve. As this value gets large the contours are less accurate but the process is faster.

·         Layers Name If this box is not empty then the contours layer will be set to this value.

Color TIN

Contour labeling



Image maps – an image colored based one elevation, aspect, or slope *

Here is an image with contours on top:


Here an image is used to wrap a surface:



A legend:


TIN From Polygon

Road Surfase Properties

Creates a set of tringles from a polygon used as a centerline.




Side slopes *

‘Side Slopes’ creates a TIN that extends from the polygon to the active surface. The slopes are determind by the angle you set.

From this:

To this:

The angle can’t be zero. The slope of the TIN extends downward to the surface from parts of the polygon that are above the surface. The slope of the TIN extends upward to the surface from parts of the polygon that are below the surface.

Calculates the volume between two surfaces

Select the from and to TINs use an elevation. The volumes above and below the from surface will be computed in drawing units.


GIS Data import

Data Formats

·         Binare Interleave Line - *.BIL

·         Spatial Data Transfer Standard - *.DDF

·         DEM ASCII

·         E00 – *.E00

·         ESRI Shape Files - .SHP .DBF .SHX

Road corridor creation based on a center line and cross section template *


This feature was derived from a combonation of the ”road from center-line” function and the “side slope” function.



With other tools the cooridore can be embedded into you TIN surface. Here is how:

Here is a closer look at a cross section produced for each station.


Road cross sections along a road center line in plan-view

            Each cross section includes:

                        Cut area

                        Fill are

                        Incremental cut volume

                        Incremental fill volume

                        Total cut volume

                        Total fill volume

            Mass haul can be saved to a file


Cut Surface with Polygon *

Just have a polygon selected.





Cross Section Defaults

Profile Defaults




Import Points * 

Launch the Import Points application.


Clipboard Access * 

If text is on the clipboard then this button will be active. Selecting it will import that text as points.


Join Polygons  

If you hav a set of polygons that you want joined into a single polygon you can use this tool to do it. Just have the polygon selected and this tool will find the ones that touch at the ends and join them together into one polygon.


Set Point z Elevation *

Have a polygon selected.

Set a value and click ‘Ok’.

Set Polygon Node z Value 

Set polygon z automatically  

When you select this button all selected text will be used to set the z values of all selected point and polygons.

Filter Data *

Cut out data from a larger set to a different layer.

See movie in “Triangular irregular network editing” above.


About box







Horizontal Curves by PI

Horizontal Curve Dialog

Select a row that represents a PI e.g. of type TANGENT. Then set a radious greater than zero. Finaly select the ‘Add’ button. Or select ‘Add Max’ which will insert the curve of maximum radius that will fit the foreward an back tangents.


Horizontal Alignments

Horizontal alignments are drawing elements which are added to the drawing when you select the ‘Save’ button.

The ‘Apply’ button applies changes in text properties to the alignment in the drawing.

            Station labeling

            Curve labeling

Tangent Labeling

            Printout for construction includes

Layout Button

The ‘Layout Button’ will save the following data to a file.

station label - in the form 00+000

station offset - absolute distance from start of center line

station X Y

bearing from PC

distance to PC

incremental cord

PCPI deflection – δn

incremental deflection

PT bearing

PT distance

PTPI deflection

center x y

bearing from center

offset from center

an arbitrary center of curve can be specified



Vertical curves

Vertical Alignments

These are the charts added to the drawing.

Profile labeling

These inlude: elevation of curve, length of curve, PVC, PVT,  slopes G1 and G2, slope of tangent areas.

Printout for construction includes:

            Curve Station Elevation Length

Critical points






The ‘Save’ button will save the horivontal alignment in the drawing.

The ‘Layout’bButton will save this data to a file.


Get Data

From here you can download the geo-referenced image of the window and the data points in a zip file. There are many base maps to choose from. The dat available depends on you zoom level.

Zoom to your area and select ‘Get Data’.

Download Data


SRTM x y coordinate are longitude latitude respectively. To project the x y of the data use the ‘Project Data’. For more information on coordinate projections here is a source for information