Graphics Programs Reference
In-Depth Information
What Are Contours?
Contours are lines that are used to represent topography or changes in elevation
across the ground. Most people experience contours in things like trail maps that
cover a large area (square miles or square kilometers) in comparison to what we
typically see in Civil 3D. By definition, contours are lines that connect points of
equal elevation. If you took a giant horizontal blade and passed it through the
ground at equal elevation intervals, you would get contour lines. In flat areas,
the lines would be far apart, and in steep areas, the lines would be close together.
With practice, you can look at a contour map and visualize the 3D shape of the
land that the map represents.
Steep Area
The Tin Surface: Existing
Ground tab is an exam-
ple of a special ribbon
tab that is displayed
because you selected a
surface. These are often
referred to as contextual
ribbon tabs, as you may
remember from the
previous chapter.
Flat Area
8. With the surface still selected, click the Tin Surface: Existing Ground
ribbon tab and then click Surface Properties  Edit Surface Style.
9. Click the Display tab, and then click the color column next to Major
Contour.
10. Choose a noticeable color, and click OK. Click OK again to return to
the drawing.
Some of the contours
change to the new
color as a result of
this change.
11. Save and close the drawing.
You can view the results of successfully completing this exercise by opening
Objects and Styles - Complete.dwg .
As you worked through the previous exercise, did you notice that no extra
steps were required to update or redraw the surface when a new style was
assigned or the style was edited? The effect was immediate—as soon as you
modified the assigned style or assigned a different style, the appearance of the
surface changed. This is because of a dynamic relationship between the object
and its style, a relationship that is honored throughout the software.
Search WWH ::




Custom Search