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342 Chapter 5: Creating Geometry
Terrain Compound Object
Select spline contours. > Create panel > Geometry >
Compound Objects > Object Type rollout > Terrain
Select spline contours. > Create menu > Com pound >
Terrain
The Terrain button lets you produce terrain
objects. 3dsMaxgeneratestheseobjectsfrom
contourlinedata. Youselecteditablesplines
representing elevation contours and create a mesh
surface over the contours. You can also create a
"terraced" representation of the terrain object so
that each level of contour data is a step, resembling
traditional study models of land forms.
Using conto ur s to build a terrain
Upper left: The contours
Upper right: The terrain objec t
Lower left: Ter rain object used as the basis o f a landscape
If you import an AutoCAD drawing file to u se as
contour data, 3ds Max names each object b ased on
the AutoCAD object’s layer, color, or object type.
A number is appended to each name. For examp le,
an AutoCAD object on the layer
BASE becomes an
object named
BASE.01 .See Importing DWG Files
(page 3–537)
for more information.
After you import or create the contour data, select
the objects, and click the Terrain button, 3ds Max
creates a new t riangulated mesh object based on
the contour data. The name of the first selected
spline becomes the name of the terrain object.
Other splines in the selection are treated according
to the previously set Reference, Move, Copy, or
Instance selection in the Pick Operand rollout,
described below.
Keep in mind that the Terrain object can use
any spline objects as operands, whether they
are horizontal splines or not. Though the most
common scenario is when sets of elevational
contours are used to crea te terrain forms, it is
possible to append or refine Terrain objects by
using non-horizontal splines.
Note: To ensure that 3ds Max imports polylines as
splines, when you import an AutoCAD drawing
file, tur n off Import AutoCAD DWG File dialog >
Geometry Options group > Cap Closed Entities.
Following are examples of uses of the Terrain
feature:
• Visualizing the effects of grading plans i n 3D.
• Maximizing views or sunlight by studying
topographical undulation of land forms.
• Analyzing elevation changes by using color on
the data.
• Adding buildings, landscaping, and roads
to a terrain mo del to create virtual cities or
communities.
• Viewing corridors and completing ridge
analyses from p articular locations on a site by
adding cameras to the scene.
Procedure
To analyze elevation changes:
1.
Import or create contour data.
2. Select the contour data, and click the Terrain
button.
3. On the Color By Elevation rollout, enter
elevation zone values between the maximum