412 Machine Drawing
dharm
d:\N-Design\Des21-1.pm5
the primitives. A solid is a model that clearly identifies any point in space at either inside or
outside of the model. Each body is represented as a single object and not as a complex collection
of surfaces.
21.10 VIEW POINT
One can view a drawing from any point in space. The VPOINT command permits to set the
viewing point for the current view port. AutoCAD generates the drawing, projecting the entities
so that they appear as one would see them from that point in space.
Command: VPOINT
Rotate/.
By choosing
Rotate: specify the view point in terms of two angles; one with respect to the x-axis (in x-y
plane) and another from x-z plane.
: one can enter x, y and z components of the desired view point (separated by
commas). A specification of “1, -1, 1” would produce top, right, front view. To generate perspective
views, one has to use DVIEW command.
EXAMPLE: An upright cylinder at zero elevation with a radius 10 units and a height of
40 units and enclosed in a square box (at zero elevation with a thickness of 15 units) can be
produced with the following sequence of commands:
Command: ELEV
New current elevation <0>: ↵
New current thickness <0>: ↵
Command: CIRCLE (draw a circle with 10 units of radius)
Command: ELEV
New current elevation <0>: ↵
New current thickness <40>: 15 ↵
Command: LINE (draw a square around circle)
In the normal 2D (top) view, this would appear on the screen as shown in Fig. 21.14a. With
a view point (1, -1, 1) top, right side, front views appear as shown in Fig. 21.14b.
(a)(b)Fig. 21.14