arcs change to circles when xrefed

[Anonymous]

Hello,

I am having a rather annoying issue with a number of arcs with a topographical survey.

Within the survey drawing the lines appear as drawn with no issues at all, however as soon as I xref the topo into my site plan the lines expand into circles. I have tried multiple regen's and changing the pdmode from 2 to 1 or 0 but nothing is working.

Please can some one advise as to what might be causing this.

I have attached a screen shot of the topo as normal and one of it xrefed into my drawing.

Update: I have tried turning off smooth edges in GRAPHICSCONFIG which solves the problem but then turns the arcs in the rest of my drawing into a straight lines.

Many thanks,

Dave

[Alfred.NESWADBA]

Hi,

>> Update: I have tried turning off smooth edges in GRAPHICSCONFIG which solves the problem

>> but then turns the arcs in the rest of my drawing into a straight lines.

Am I correct that after you run command _REGEN you do have the display of arcs corrected?

- alfred -

[rkmcswain]

Sounds like a display driver issue. Are you running a supported adapter with the recommended driver?

As a temporary workaround, try disabling hardware acceleration.

[Anonymous]

Does regen work

[Anonymous]

Hi Alfred,

Unfortuantely no.

I have tried regen multiple times with the arcs remaining a straight lines after turning off smooth line within the graphicsconfig menu.

I don't know if its worth noting or not but I am unable to turn off smooth line without turning off high quality geometry.

Thanks

[Anonymous]

If I disable hardware acceleration I have the same problem as turning off smooth lines.

It solves the problem with the arcs in the xref however the arcs in my drawing become straight lines which causes more issues

[chriscowgill7373]

Check your Display Resolution settings within the Options Dialog -> Display tab.

[Alfred.NESWADBA]

Hi,

>> It solves the problem with the arcs in the xref however the arcs in my

>> drawing become straight lines which causes more issues

Do you first run _REGEN and then ZOOM to see how the arcs are displayed ... or do you first ZOOM and then run _REGEN (second option is the correct workflow).

I can't imagine that arcs are then displayed as lines.

- alfred -

[Anonymous]

I zoom then run REGEN and the lines do not change back to arcs. 

I have attached a screengrab of one of the areas effected.

This is after I have zoomed in and tried regen.

[Alfred.NESWADBA]

Hi,

>> I have attached a screengrab of one of the areas effected.

>> This is after I have zoomed in and tried regen.

Strange ... by any chance: are the coordinates at very high values (> 10^6)?

Can you upload the drawing so we can test these objects on our systems, just to see if that is something drawing-specific and happening on our systems too?

- alfred -

[Anonymous]

Hi Alfred,

I have uploaded the file in question as a dwg.

Thanks.

[rkmcswain]

david.gratton wrote:

If I disable hardware acceleration I have the same problem as turning off smooth lines.

Can you please tell us what model display adapter you have and the driver version? If one or both are not on the certified/recommended list, the symptoms you are describing can happen.

[Anonymous]

Where would I find this information please?

[rkmcswain]

Run the GRAPHICSCONFIG command, snapshot the dialog, attach here.

Example below.

[Anonymous]

I have attached the graphicsconfig below

[rkmcswain]

Unless I overlooked it, we do not know your O/S or AutoCAD version. So I can't look it up, which is why I included the link in post #3 to the Recommended hardware/driver list.

[Anonymous]

I am running windows 10 and my autocad is LT 2017

[Alfred.NESWADBA]

Hi,

have you seen post 10 in this thread and verified the coordinates?

That are your coordinates:

X = 608680518.2573     Y = 238580124.3342

And these high values are very close to the limit of double precision calculation.

Scale your drawing by 1/1000 and set your units to Meter instead of Millimeter and all is well 😉

- alfred -

[Anonymous]

Hi Alfred,

Unofrtuantely we only work in millimetres as an architectural practise. 

We had to scale the os by a factor of 1000 to covert it to millimetres and then xrefed in the topo. We then repositioned the os data to suit the topo position which came in at those coordinates. 

Is there anyway to solve the problem without converting the drawing back to meters?

thanks

[Alfred.NESWADBA · Accepted solution]

Hi,

>> Is there anyway to solve the problem without converting the drawing back to meters?

Your coordinates are too far away from 0,0 and with such high coordinates you'll get less digits (behind the decimal separator) for mathematical calculations. That's not a limit of AutoCAD, that's a limit of double precision/how coordinates are stored in CAD-systems.

Also these high coordinates not only have issues with the display, also with commands like TRIM or EXTEND, with object-snap like INT and a lot more...

You can stay in Millimeter, but then you need to move your geometry to 0,0 ... and if you want to have that dwg at correct coordinates I can use XREF to insert your drawing (close to 0,0) and move/rotate/scale the referenced object to the correct location.

If you work in Meter, you won't have all that issues.

- alfred -