Autodesk 057B1-41A111-1001 - AutoCAD LT 2010, Руководство пользователя

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be independently drawn and positioned, this type of modeling can be the
most time-consuming.
You can use a wireframe model to
■ View the model from any vantage point
■
Generate standard orthographic and auxiliary views automatically
■ Generate exploded views easily
■ Analyze spatial relationships, including the shortest distance between
corners and edges, and checking for interferences
■ Reduce the number of prototypes required
The ISOLINES system variable controls the number of tessellation lines used
to visualize curved portions of the wireframe. The FACETRES system variable
adjusts the smoothness of shaded and hidden-line objects.
Methods for Creating Wireframe Models
You can create wireframe models by positioning any 2D planar object anywhere
in 3D space, using the following methods:
■ Enter 3D coordinates that define the X, Y, and Z location of the object.
■ Set the default work plane (the XY plane of the UCS) on which to draw
the object.
■ Move or copy the object to its proper 3D location after you create it.
Wireframe modeling is a skill that requires practice and experience. The best
way to learn how to create wireframe models is to begin with simple models
before attempting models that are more complex.
Tips for Working with Wireframe Models
Creating 3D wireframe models can be more difficult and time-consuming
than creating their 2D views. Here are some tips that will help you work more
effectively:
■ Plan and organize your model so that you can turn off layers to reduce the
visual complexity of the model. Color can help you differentiate between
objects in various views.
■ Create construction geometry to define the basic envelope of the model.
■ Use multiple views, especially isometric views, to make visualizing the
model and selecting objects easier.
300 | Chapter 8 Work with 3D Models