Contour Lines

Digital Terrain Model

You can use the Contour Lines tool to draw contour lines in a DTM.

To create contour lines

1. Click Contour Lines (How).
   

   Activate Contour Line in one of the following ways

   • Menu bar: Create Terrain Digital Terrain Model

   • Palette: Tools Create area in the following module(s):

   Digital Terrain Model

   • Configuration: Landscaping/Urban Planning Digital Terrain Model flyout
2. Click the DTM in which the contour lines are to be drawn.
3. Enter the minimum height.
4. Enter the maximum height.
   If the maximum height is the same as the minimum height, only a single contour line is drawn.
5. Enter the difference in height between the contour lines.
   The contour lines are added to the DTM.

Examples

Contour Lines, An Example

1. Example: Linear model without smoothing factor

Height minimum: 0.0 m Height maximum 5.0 m Height difference: 1.0 m

2. Example: Linear model by smoothing factor

Height minimum: 3.0 m Height maximum 3.0 m

Notes

• You can control the resolution and the interpolation of the contour lines by setting the smoothing factor in the module’s options. They then appear more ”rounded.”
• Only contour lines that do not exist are created. All the main lines should be drawn every 5 m, say, with a thicker pen, followed by thinner lines in between (spaced at 1 m intervals, for example).
• You can use the DTM Filter in the Filter Assistant to address all contour lines together for manipulation.