I cant create regions in drawing

[graham]

I have an issue where I create regions from closed line shapes within certain drawings.

I constructed certain closed elements that did create regions in plan view.

However, later in the session I have exploded these elements to edit further, but they do not create regions again.

Even if I explode the existing region and then immediately try and resave as a region it fails

Command line says : -

''1 closed, degenerate or unsupported object rejected. Open objects must be coplanar. 0 Regions created.''

I did a recover on the drawing which highlighted 4 errors, but the problem remains, but the command now just say's

''Open objects must be coplanar''

2 weeks work with this, and it is in several drawings (or my settings ?)

If I p-edit one of the lines and turn the shape into a polyline (by join) I can save the resulting polyline shape shape back into a region.

Can someone please help - Is t is a Release 2015 glitch ?

Is there a setting that will help me ?

[kasperwuyts]

It's always handy to post a dwg example so we can look. Otherwise, try the FLATTEN command on your geometry and try the region command again.

[graham]

Thanks

I was not aware I could do that.

Here is an example 

This was a region, but after exploding did not want to go back as a region, unless I pedit the line and made it into a joined poyline first.

[steven-g]

It worked fine for me. How are you trying this, or do you have lots of other geometry in your actual drawing. The region command is usually pretty forgiving in what it will accept but you do have to be careful with lines that are shared.

[kasperwuyts]

FLATTEN and REGION does the trick in your sample.

[graham]

Thanks very much !

I had not hit the return (on show hidden line) when I tried 'flatten' command before.

One question does remain therefore

How did the exploded region (that was) become unflat when exploded (if you see what I mean)

[pendean]

>>>...unless I pedit the line and made it into a joined poyline first....<<<

Exploding a region-object creates a cluster of lines.
REGION command doesn't work with LINE objects unless you select each and every line first (in 2015 where I tested): are you selecting each and every line that identifies your closed future-region object?

[graham]

Yes, but this is not really the issue.
Kasperwuyts has given me something that works, but I cant see why the lines that had once formed a region, should after exploding, have to be 'flattened' before being made into a region once more - as the geometry has not changed.

[pendean]

Without your DWG with a region that explodes that way for all if us to see it in action it's hard to guess why.
Got one?

[graham]

the one I sent is an exploded region that I cant just do a region command on and make it a region again.
I have to flatten it first (but why ?)

[stevetamplen]

I took your file and experienced the same behavior in AutoCAD 2015. 

I noticed that the shape will hatch ok, so there are no breaks in the boundary objects. 

When I create a similar object on the XY plane, I can create a region, explode it, and re-create the region with no problem.

I appears that your object was not created on a single plane. That is why it works after flattening, which pushes all of the objects down onto a single plane.

[pendean]

Was hoping you had a pre-exploded one since a REGION is a 2D element: your "after the fact file" offers no information that points to the actual state of the original object.

[stevetamplen]

My apologies. I meant that when the object was edited after it was exploded that some of the new elements were created (or existing objects moved) off of the plane that the rest of the objects occupied.

Is there a sample of the object before it was exploded that I can test?

[graham]

Thanks Steve.

But the object was a region, so must have been flat ?

I can also pedit one of the lines and join them, and after create a region, which should also mean the shape is flat ? (as per the sample sent)

I thought I read something somewhere about some setting to do with corner spacing or something ?

UnfortunatelyI Exploded all the elements and resaved without noticing issue, so no regions as were available.

I may just have to go with the flattening solution for now.

I am just hoping a cnc router software doues not miss something out in a large sheet as a result

[stevetamplen]

Yes, I tried PEDIT too, and that also worked to re-create the region.

In answer to your question, it would have been flat when created, but as I don't have the original unexploded object, and do not know what edits you performed, I can only speculate about what caused the original issue.

Have you tried to re-create the original object in a new drawing file and see if it experiences the same behavior?

[steven-g · Accepted solution]

As I posted earlier, I had no issues taking your drawing and creating a region without any need to flatten, I use 2013LT so there is a possibility that there is a setting or behaviour difference in 2015.

[graham]

Thanks Steven
That would be my conclusion too.
It's not really a solution though ?
This is the 3rd issue I have had with 2015 in the short period that I have been using it, and I cant say I'm impressed.
I am going to move on and put this one down as a solution and possibly re raise it when I can give an example of a region that proves the point

[stevetamplen]

Since I can't replicate the issue in a new drawing, or with a new object in your drawing, I am stuck for another explanation. I am using 2015.

Can you tell me the exact method you used to create the original object? Then a list of the edits you performed, or possible a short video. That would help me to re-create the original issue.

If you see the same behavior again, please post the file here.

Have you downloaded/installed SP1 yet? If not, you can get it here:

AutoCAD 2015 Service Pack 1

It adds stability to the software.

[habib7770]

I have the same problem in autocad 2017, and I have the dwg file. please take a look and see what id the problem. 

I have a solid. I exploded it. took the region with holes and exploded it again to get all the lines and curves . immediately after exploding I cant create the same region. error: objects must be co-planar.

-  flatten solves the problem in this case , but the question is why the objects are not in the same plane after exploding.

[loyadanieln]

worked for me, thanks!