It may seem like a great idea to use the layer “DEFPOINTS” as the layer for your viewports since it doesn’t plot by default. And you may have heard from various posts that you shouldn’t do so but may have not understood why…
Here’s why:
It has to do with both Layer 0 (zero) and Defpoints.
Note: I am using “Layer 0 (zero)” because I dont want the zero to be confused as the capital letter O.
Layer zero is reserved for objects like blocks so if they are set to layer zero and you insert them into a drawing, the current layer could be set to anything, and that block will now be on that layer. So CAD managers might have Layer 0 (zero) turned off or even frozen so that people don’t use this layer to draw objects that should be on a designated layer.
If layer 0 (zero) is not turned off or frozen, you can select everything as normal (shown below
Let’s say that you Freeze Layer 0 (zero) [shown below]
Now try to select the same layers that were select-able prior to Layer 0 (zero) being frozen. You will notice that you cant select the objects that are on the DEFPOINTS layer. It’s like some sort of force field has been applied to these objects…
So how will this cause issues?
If your viewports are on the DEFPOINTS layer, and you want to later come and change the scale of the viewport, you will not be able to select the viewport. However, you can still double click inside the viewport to adjust the scale but some people use DEFPOINTS for placing other objects that they don’t want to plot like text that serve as notes or whatever. If they later what to erase them or move them or edit them, they wont be able to do so.
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All very true, but to me, the overriding issue is more one of drafting “philosophy,” namely that the DEFPOINTS Layer is called that for a reason — it’s for DEFinition POINTS for associative Dimension entities. That’s what should be on it, and not unrelated other things. The Layer on which something resides should be meaningful in relation to the purpose of the entity. (Besides, you might have occasion to want Dimension definition points turned off or frozen, but not Viewports [or vice versa] — then what do you do?) The fact that DEFPOINTS doesn’t plot should be totally irrelevant to anything whatever about Viewports, layout linework, etc., etc. I think the commonness of its use for such things dates back to the days (pretty long ago now) when it WASN’T POSSIBLE to designate a Layer as non-plotting, and DEFPOINTS was the only one like that. But that limitation is long gone. Make yourself a non-plotting Layer for Viewports, and others for anything else that you want to be able to see but don’t want to show up in plots even when you leave it visible.
Thanks for your thoughts on this issue Kent. It is always good to hear why some of these older drafting habits have continued from you old-timers ;) Now that I’m unemployed, I am trying to remember some of the issues that have arisen over the few years I was a CAD admin and document them here on my blog so that I can refer to them in the future. Some of them i made sure to document on here but there are plenty of others that I simply forgot to or was too busy to document
A user came to me wondering why some objects weren’t selectable. And then it came up again when someone couldn’t select their viewports.
Thanks again Kent,
~Greg
As an “old timer” myself Kent is right. I actually remember Lynn Allen and others teaching this workaround in the days when Autocad had release #’s… like 2.2 and 2.3 :)
I create a “VIEWPORT” layer and set it to no plot. Often I will set up a “VIEWPORT-PLOT” layer for when I DO want the viewport to plot. Both at at the end of the listing so they are eacy to find. I set the lineweight to ~ 5mm and make these two layers different colors so I can differentiate between them easily.
R
I also create a VPORTS layer and set the layer properties for it not to print, I also create a “NO_PRINT” layer for annotation / construction lines I don’t want printed.
very easy solution
go to layout space
then
select all through Clrt A
&
deselect all accept view port
&
change the layer
after that it will be able to select
thanks