Circle displaying in Viewport, but not in Model space

Hi all

I'm working on some information that I have imported into LT 2017 from 12D survey software. Basically I have a road string (polyline made up of arcs) and I'm tidying it up. All I have done to this string is break it and change the layer it is on.

When I go into Paper space and look at my plan layout, the broken polyline displays as though it is a full circle. In Model space it looks how it ought. I have double-clicked in the viewport and selected the circle and changed the colour for easy identification. Then, when I go back to Model space, I have a red curved polyline. No circle.

I have also tried copying the polyline as a block and pasting it into paper space. It displays as it ought to. If I paste it back into Model Space, it retains its characteristics - i.e. curve in model space, circle in paper space.

If I explode the polyline into its component arcs and join them together again, it begins to behave properly.

This never used to happen in prior versions of CAD, and my co-worker has had a similar problem. She says it's not a consistent fault - sometimes the display behaves and sometimes it doesn't.

I have run audits and purges and all sorts of fun things and have achieved nothing. It prints correctly, but the preview shows it as a circle also.

Any ideas, or similar issues?

Can you post a portion of the file that does this? It would also be helpful if you posted both screen shots at the same zoom level and kept the same colors.

First thought would be a graphics display problem, what are you Computer Specifications?

Using AutoCad LT 2016 at work. Before I changed from the onboard video processor, to an aftermarket one, I often had the inverse side of an arc (the missing part of the full circle) appear rather than the arc as drawn. This looks like what is happening. My instances would occur in modelspace when the actual arc(s) were near the edge of the display screen. They'd usually disappear when I changed the zoom or pan. They never plotted incorrectly, and have gone away with an extra 4 gig of dedicated RAM for graphics.

System info, trimmed file and clearer screen shots attached.

System.txt

file.dwg

Welcome to CADTutor.

It certainly sounds like Dana was spot on with his evaluation,

based on his personal experience on LT.

Before I changed from the onboard video processor, to an aftermarket one, I often had the inverse side of an arc (the missing part of the full circle) appear rather than the arc as drawn. This looks like what is happening. ... They'd usually disappear when I changed the zoom or pan. They never plotted incorrectly, and have gone away with an extra 4 gig of dedicated RAM for graphics.

When you say "extra 4GB" what does that make your total dedicated RAM? Zooming and panning doesn't change the display for me.

When you say "extra 4GB" what does that make your total dedicated RAM? Zooming and panning doesn't change the display for me.

Dana posted another thread within the last week, where he said that he was running 8GB, and had just added another 4GB, so it sounds like he now has 12GB on his work machine.

Dagad: What I believe Dana was referring to was the upgrade from an onboard graphics chip to a dedicated graphics card which happens to be a nvidia Quadro K4200 with 4GB of onboard vidRAM and the topic of one of his recent threads.

I would say it is the Graphics Card, never cared much for AMD on AutoCAD and I didn't see an Autodesk Driver for that one, looks like a low end Gamer Card maybe.

Try a different driver and/or turning off hardware acceleration.

Did you try running an Audit or Recover on the drawing to fix any errors?

Dagad: What I believe Dana was referring to was the upgrade from an onboard graphics chip to a dedicated graphics card which happens to be a nvidia Quadro K4200 with 4GB of onboard vidRAM and the topic of one of his recent threads.

The quadro replaced the on board Intel HD 8086-0152 video chip which only directs video processing to available CPU RAM, and the swap file when there is no RAM available (most of the time), so I basically went from 1.37569874 gig to 4.0. It got rid of my phantom circles, and is making it easier to navigate the screen when it is loaded. It is probably saving 5 to 10 minutes a day, judging by my co-worker's remarks that I don't curse at my computer nearly as much.

When you say "extra 4GB" what does that make your total dedicated RAM? Zooming and panning doesn't change the display for me.

So I am attempting to upgrade the driver on my AMD graphics card. It's quite slow and I think it may have crashed last time I attempted it, so we'll see how that goes. I tried turning off the hardware acceleration, and that actually fixed the phantom circles. Thanks SLW210

I also looked at the Autodesk Hardware Advisor and see that a Core i3 probably isn't going to cut it. Which is not surprising really - even looking at CPUs for a new home computer I had decided that i3 wasn't sufficient and I don't use it for anything like what I do at work. Maybe the IT guy is future-proofing for HIS business, rather than ours?

No cursing about the phantom circles here, but we'll see if turning off the acceleration makes anything else crop up. Thank you for all your help, guys.