2012

Define a Perspective Projection (DVIEW)
Perspective projections require a distance between a theoretical camera and
a target point. Small distances produce severe perspective effects; large distances
produce milder effects.
A perspective view remains in effect until the perspective effect is turned off
or until a new view is defined in its place.
To define a perspective view of a 3D model using DVIEW
1 At the Command prompt, enter dview.
2 Select the objects to display.
3 Enter ca (Camera).
By default, a camera point is set at the center of the drawing.
4 Adjust the view as if you're aiming a camera.
A representation of a house shows the current viewing angle. You can
set your view dynamically by moving the crosshairs and clicking.
5 To switch between angle-input methods, enter t (Toggle Angle).
You also can adjust the view with one of two angle-input methods.
■ For the Enter Angle from the XY Plane option, enter the angle of the
camera up or down relative to the XY plane of the current UCS. The
default setting, 90 degrees, points the camera straight down from
above.
After you enter the angle, the camera is locked at that height, and
you can rotate the camera about the target with the rotation angle
measured relative to the X axis of the current UCS.
■ For the Enter Angle in the XY Plane from the X Axis option, rotate
the camera about the target with the rotation angle measured relative
to the X axis of the current UCS.
6 To turn on the perspective view, enter d (Distance).
7 Specify a distance, or press Enter to set the perspective view.
You can use the slider bar to set the distance between the selected objects
and the camera, or you can enter a real number. If the target and camera
points are very close (or if the Zoom option is set high), you might see
only a small part of your drawing.
286 | Chapter 10 Change Views