At times despite our most diligent efforts,
we inadvertently change the VP scale of a viewport, and end up with a
plot that has an incorrect viewport scale.
With all of the tools available, there surely is a way to have AutoCAD
display the viewport scale dynamically. Advanced users with programming
expertise could do this programmatically using LISP and reactors, but there is
also a much simpler solution: AutoCAD fields.
Here is a great way to dynamically
display your VP scale, using fields in mtext.
A field is a text representation of a
specific object property or value of a drawing or system variable. Fields appear
as normal text when plotted, but have a grey background onscreen, like this. The big
difference between text and fields is a field will update if the element it
references is changed.
Some examples of field variables are: drawing
name, login name, date, time, layout name. Fields can also display object
properties such as object name, layer, color, linetype, and specific properties
such as block name for blocks, center point of circles and arcs, or area of a polyline,
or SCALE OF A VIEWPORT!
For this you will first need a viewport in
your layout to assign the mtext field. The
next step is to create an mtext object, a good location is in one of the
corners, perhaps lower left or lower right, either inside or outside. You can
create some descriptive text as well, like "VIEWPORT SCALE ", and in
the mtext editor right-click and select Insert
Field... from the context menu; the Field dialog will appear.
In the Field dialog, select
the following
(as shown in the graphics):
Field category: Objects,
Field names: Object,
Object
type: Viewport, (to acquire the viewport, click the select objects icon to the top right of the Object Type area, and then select the viewport object
Property: Custom scale,
Format: Use scale name.
AutoCAD will display the annotation scale (if
applied) or the value of the VPSCALE variable.
Since fields are dynamic, the dynamic scale
will refresh with every open, save, plot, etransmit or regen (If this is not happening, set FIELDEVAL to 31). If you wish to see it but not print it, place
the mtext field on a non-plotting layer.
There you have it: a dynamic VPSCALE display!
