Geometric center problem

[patrick.bijsterveld]

Hi,

problems / strange occurences with the geometric snap function.

when drawn a square far away from the ucs the geometrical center is way of, even when switching to a ucs nearby.

with a new square (copied or drawn new) positioned nearby the ucs, the problem is gone.

see attachment, same squares different geometrical centers.

is it a bug?

[strawberry12]

I think it's a floating point error. I think it's why hatch patterns drawn far from the origin are often mangled. A simple fix is to move the ucs origin closer to the object.

[patrick.bijsterveld]

when i move the ucs towards, or even on the object with the problem , the geometric center is wrong.

[Emmsleys]

What release of AutoCAD are you working on? 2015,2016?

What Windows release are you working with? 7,8,10? 

[pendean · Accepted solution]

See your file, reattached: red Plines are mine, AutoCAD2016, I did nothing special except I had Geometric Center as a running Osnap when I drew the PLINE. It seems to work just fine.

Walk me through how you drew yours, step by step, line by line: maybe I missed something.

[patrick.bijsterveld]

autocad LT 2017, windows 10

[patrick.bijsterveld]

i tried to reproduce the error, but it failed.... i've restarted my pc this morning and restarted autocad 2017LT, opened the file i attached yesterday and the flaw was gone.....

i thank everybody for the reply , and i hope the error does not occur anymore..

[Emmsleys]

Thanks for providing a update, post back if the issue happens again. If it does try monitoring your system to see what might have changed to cause the issue in the first place. 

Thanks. 

[david_pannell]

Hi, I am experiencing the same issue on AutoCAD 17 Full version it is only on selected drawings and geometric centre is off by miles or in some instances, only by 10mm....

Did anybody else experience this? I am noticing it on a selection of drawings and when I place anything from the effected files into new drawings.

[pendean]

Show us that DWG file with that problem: we all have R2017.

[david_pannell]

Attached with some notes, it seems to be DWG's from the architects.. I cant figure out why.

[pendean · Accepted solution]

So your notes point to a block who's insertion point is also the center of the larger rectangle that you are trying to hit: any reason you are not grabbing it from there?

And I seem to be able to find that same point in AutoCAD 2017 using the Geomtric Center too, but I cannot repeat your two points using any other method

[david_pannell]

Sorry, I should of deleted the furniture, I'm looking for the centre point of the red rectangle.

The red circle/line is where ACAD is telling me the center is, but I know its where the blue is shown as its a regular rectangle.

[patrick.bijsterveld]

i still have the same issue. unknown when it happens though. it's perstistant....

[david_pannell]

It somehow copies across any drawing those objects are copied into, I feel like this is going to be a long afternoon just finding the one item causing it 😞

I wouldn't mind but I got over 500 rooms to place fittings into and geometric centers are best positions to work off for lights/smoke detectors 😞

All I can assume is an object on this drawing is causing all geometric centres to go off... I will now just copy and paste slowly hoping its a specific item and that its not all layers/objects associated to that .dwg

[patrick.bijsterveld]

in my experience , the problem copies with it. only new drawn items are then problem free..

[pendean]

If I leave your red rectangle in place, it does not work at all here.

If I move it, it works fine

Weird indeed: looks like you'll have to rely on MTP or M2P osnaps for most of your uniform shapes in this file until someone comes up with a tip that consistently works.

[david_pannell]

It is a strange one, I can only blame it on something in the drawing I have purged, audited, copy pasted, saved as different files, xref'ed it but the error follows it like a bad smell!

This is going to be fun to produce 32 floors with varying room layouts :'(!

Thanks for the replies though.

[david_pannell]

Small update, I have tried removing all blocks, hatching, saving down and up versions and it is still persisting...

I'm just now worried a colleague will use items off these DWG's and "infect" all of ours, as they often try do CAD themselves and just copy off other drawings.

[david_pannell]

Another post... and hopefully this may help!

I have emailed the Architects I got these drawings off, and it seems they were produced in Microstation not AutoCAD, now I think it could be linked to the conversion process, would that little nugget be able to help anybody figure out the cause of this problem?