Computer Aided Draughting 409
dharm
d:\N-Design\Des21-1.pm5
UNDO Command—this command allows to undo several commands at once. This
command is used for correcting any errors made in the editing process. When a SAVE option is
used, then the UNDO cannot do anything before that.
Command: UNDO
If the response contains a number, that many number of preceding operations will be
undone.
REDO Command—if REDO is entered immediately after a command that undoes
something, it will undo the UNDO.
Command: REDO
An UNDO after REDO will redo the original UNDO.
OFFSET Command—this constructs an entity parallel to another entity at either a
specified distance or through a specified point.
MIRROR Command—this allows to mirror the selected entities in the drawing. The
original objects can be deleted (like a move)/retained (like a copy).
MOVE Command—the move command is used to move one/more existing drawing entities
from one location in the drawing to another.
COPY Command—this is used to duplicate one or more existing drawing elements at
another location without erasing the original.
21.8.2 Zoom Command
This command acts like a Zoom lens on a camera. It is used to change the scale of the display.
This can be used to magnify part of the drawing to any higher scale, for looking closely at some
fine detail in the drawing. This is often quite useful during the construction stage. If zoom
closer, more details are visible but only a part of the drawing is seen, whereas if zoom out,
larger portion of the drawing is seen but less details are visible. This command can be invoked
from standard tool bar, from the pull down menu bar, from screen menu or from the command
area by entering zoom.
Command: ZOOM
All / Centre / Dynamic / Left /Previous / Vmax / Window / :
By choosing the option:
All — complete drawing is seen in the drawing limits, even though a part of the
drawing lies outside the limits, earlier.
Centre — this option permits to specify the desired centre point. By specifying the
height of window, the magnification can be increased / decreased.
Left — it permits to specify the lower left corner of the display window instead of
the centre.
Dynamic — this displays the portion of the drawing specified already. Generally selects
any portion of the drawing.
Extents — all the objects in the drawing are magnified to the largest extent possible
in display.
Previous — the previous display extents are restored to the monitor, but the erased
objects do not reappear.
Window — by entering two opposite corners of a window, the area inside the window
is enlarged / reduced.
