How to create surface (contours)

Background

At the start of every project, whether it involves road or pipeline design, a surface must be created for the planning. The surface represents the topographical area where the project will be designed, created by inputting ground data into the software. In CivilCAD 11, you can generate multiple customized surfaces. The two basic surfaces are Topography for existing ground conditions and Design for the planned ground conditions.

Initial Setup

You can create a surface using points from a coordinate list or by importing a LandXML file. If you have a DWG file with points or contour lines to create the surface from, see the Filtering page first. If you want to use a coordinate file, ensure it is uploaded to the coordinate window as described on the Coordinates - Additional Operations page.

Now, right-click on one of the surfaces listed in the Workspace, choose “From coordinate list,” and select the coordinate list to create the surface. Then, right-click the surface again and select Update surface. The surface will now be built according to user settings. Additional settings can be configured by clicking on Option as explained below.

Alternatively, you can create the surface by reading a LandXML file. To do this, right-click in the menu on From LandXML, select the appropriate file, and then click Update surface as mentioned.

WORKSPACE Menus

Right-clicking on Surface opens a window with the following options:

- New surface: Add a new surface to the surface list.

- New folder: Add a new folder to the surface list to organize surfaces.

- Section: Open a window for quick section creation.

Right-clicking on the surfaces opens a window with the following options:

- Update surface: Update the surface according to the settings. Rebuild/update the surface after changes.

- Zoom to: Focus and find the surface.

- From coordinate list: Choose the coordinate list to create the surface.

- Set boundaries: Define boundaries within which the surface will be calculated.

- Set breaklines: Define breaklines for the surface.

- From LandXML file: Create the surface from a LandXML file.

- Export LandXML file: Export the surface to a LandXML file.

- 3D view: Display the surface in 3D.

- Rename: Change the surface name.

- Properties: Various settings.

- Delete: Delete the surface and refresh the drawing to update it accordingly.

Tools and Settings

In the Properties window, various personal settings for each surface are available. After setting/changing the settings, click Update surface to rebuild the updated surface.

Setting the Contour Line Calculation Area

Upon opening the contour line window, you’ll see a large frame with the word: Extents, indicating that contours will be calculated for the entire drawing area by default. Choose Locate from the list in the right window, go to the drawing area, and define the desired area by specifying its boundary points. Type C and Enter in the command line upon completion. After defining the contour area, click Apply or Update surface to create it.

Alternatively, you can define the area by entering the boundary points’ names: Enter the points' names in the text box at the top right. Press Enter between each point. You can also enter a range of points numbered sequentially, like 100-110. After entering, press Enter and then Update surface to create the contours.

Using Polyline to Set Boundaries

Choose Select from the list on the right, or Set boundaries by right-clicking on the relevant surface in the WORKSPACE. Go to the drawing, select the marked Polyline, and press Enter. The right window will display a list of <Noname> points. Click Apply to get the contour lines.

Show Triangles

Check this option to display the interpolation triangles in the drawing. The software performs triangulation to create the contour lines. It automatically chooses triangles, linking each point to its nearest neighbors to avoid overlapping triangles or uncovered areas.

Fix Borders

Automatic boundary correction: If no precise boundary is defined, the entire project area is considered. You can instruct the software to automatically correct the contour area boundaries, removing long triangles to avoid unnecessary connections.

Show Borders

Display the contour boundary if defined. If not, the software will mark the calculated boundary and display it.

Create Triangles Only

The software will not display contour lines but will create the triangle mesh in memory. Calculations can still be performed even without visible contour lines.

Smooth

Smooth the contour lines: By default, the software creates precise contour lines according to the triangulation. You can instruct the software to smooth these lines. Check the Smooth field and click OK. The software will smooth the contour lines, which may result in less accurate representation in areas with discontinuities.

Max Interpolation Length

Set the maximum interpolation distance: By default, CivilCAD interpolates between all existing points. You can set a maximum distance for this interpolation. For example, entering 60 meters (units in meters) and clicking Apply will limit interpolation to points within 60 meters of each other. This removes undesirable triangles.

To apply any of these options, check the box next to the option and click Apply. The software will calculate and draw the contour lines according to the defined settings.

Pick Height

Label heights at specific locations: Sometimes the default label placement is unsatisfactory. You can instruct the software to add height labels manually. Mark the Pick option, go to the drawing area, and create a line that intersects multiple contour lines. Heights will be automatically labeled at the intersections. To prevent height labeling in unwanted layers, freeze those layers, use Pick height, and then unfreeze them.

Contour Line Window Buttons

Other buttons in the contour line window:

- Highlight the contour area immediately with a yellow line.

- Delete the boundary points list and return to calculating the entire area.

- Delete a specific point from the boundary points list.

- Confirm changes to the contour calculation boundaries.

- Open the contour settings tab (Options).

Additional Settings

Clicking the Options tab opens a window with further settings.

Auto Elevations

When checked, the software automatically labels contour heights. Removing the check and recalculating contours results in lines without labels.

Barracks

Check to draw square brackets around height labels, distinguishing existing contours from planned ones.

Format '##.#'

Check to format heights as ##.#. For example, 3.25 remains 3.25, but 3.20 becomes 3.20 (not 3.2).

Scale

Control the contour label size. Change the number next to default to the desired size.

Font size distribution by scale is as follows:

Up to 1:100 font size: 0.1

Up to 1:250 font size: 0.5

Up to 1:500 font size: 0.7

Up to 1:1000 font size: 1.2

Up to 1:1250 font size: 1.5

Up to 1:5000 font size: 5

Up to 1:10000 font size: 10

Note: During printing, the text will be printed as it appears on the screen. A font size of 100 corresponds to a print scale of approximately 1:250.

Show Flow Direction

Check to display water flow direction with arrows, showing height gradients.

Contour Layers

Contour lines are divided into layers based on their intervals, meaning all contour lines with a 1-meter interval, for example, will be placed in one layer (100, 101, 102, etc.). We can control the contour line layers. Note that the division into layers depends on the intervals between the contour lines decided during the calculation. In the Options window, there is a label "Layers". Under this label, there is a table of contour line layers, with each number representing a layer. You can browse through the layer properties by selecting the desired layer with the mouse. Other data (Double, Unused, etc.) displayed in the frame represent the properties of the highlighted layer.

Let's discuss these properties:

Intervals - Contour line intervals. As mentioned, we divide the contour lines into layers based on their intervals. In this window, you can set the layer's characterization, i.e., which lines will be included in this layer. If you write 0.5, for example, all lines with 0.5-meter intervals will be included in this layer. Setting 0 for intervals instructs the software to place lines without defined layers into this layer.

If, for example, the layer division we created is as follows:

Unused

Mark a layer as unused to deactivate it.

Auto Elevations

Automatic height labeling. If this option is selected, the heights will be automatically labeled.

This labeling will be affected by the Auto Elevations option. For any layer where we do not want automatic height labeling, we will uncheck the option next to it.

For example, if we do not want automatic height labeling for the layer with 0.25-meter intervals, we will highlight this layer in the list (assuming, for example, that we have designated layer 3 as such - 0.25 m) and uncheck the Auto Elevations option next to it.