Various display glitches with pointclouds

[TanguyNed]

Hello,

I'm experiencing different display glitches with pointclouds.

1) when zooming/panning, frequently a small part of the point cloud will keep appearing where it's not supposed to be. See https://youtu.be/UIpjhMYODTk. Notice how some points are appearing out of nowhere. This is NOT a registration issue !

2) I like to orbit frequently around the pointcloud, it helps with visualizing and understanding small details. I've set auto-target to off so that I can "snap" the orbit pivot point to the location I want to orbit around, but the pointcloud keeps appearing and disappearing. See https://youtu.be/dmtPDRhj9_g.

Notice how the UCS is jittering around. The closer I zoom, the more likely it is to happen. I also have some objects in the drawing, when I delete them completely the glitch doesn't happen anymore.

3) in intensity mode, points with a very high intensity show as RVB colors, despite the max intensity set to 100 in the point cloud color map dialog box (can't set it higher !). My guess is that those points are given an intensity higher than 100, which shouldn't be the case. See attached pictures. I don't have this issue in Recap.

As for my specs, I'm using AutoCAD 2017 SP1, Windows 8.1, core i7-4790 3.60Ghz, Quadro K4200 with recommended drivers and 16 Go RAM. I tried disabling all options in the hardware acceleration settings to no avail.

Anyone else with these issues ?

[TanguyNed]

Little update : #2 was because I had xlines in the drawing. Apparently 3Dorbit doesn't like that. Delete them and everything is fine again.

Still no idea for #1 and #3.

[john.vellek]

Hi @TanguyNed,

I have seen this issue appear a couple of times.  Some users report that simplifying the point cloud (remove some points) can help to improve this behavior. You might also check to see if the data is located close to 0,0,0.

[TanguyNed]

Thanks for your input. The data was close to 0,0,0, and I can't really simplify the pointcloud further without deleting useful points.

Anyway it's not THAT annoying but I still hope a developer could have a look at this.

[john.vellek]

Hi @TanguyNed,

I am currently working at AU Las Vegas but fortunately I am sitting next to a support specialist that deals with these features all the time. Is it possible to share your point data?

He also suggests that you try opening the data in ReCap to see if they behave properly in that application.

[TanguyNed]

OK, I will upload the pointcloud during the night, and share the link tomorrow. But it happens with every pointcloud, it's not project specific. As you said you've already seen this issue with other users (we're still talking about issue #1, btw?).

Just reference a pointcloud, make a section, and zoom in an out. Sometimes the glitch doesn't manifest itself immediately but only after some time working on the drawing. It's also not everywhere in the drawing but here and there at random. This might be a difficult one to replicate.

After further testing, it only happens when the pointcloud has an active section or has been clipped.

Everything looks good in Recap.

[TanguyNed]

Here is the link: http://a360.co/2g4fAZI. I've also attached a DWG where the pointcloud is already referenced and a section was made. Zoom in the red circle. There is a part of station 21 that is duplicating itself where it shouldn't be.

[john.vellek]

Hi @TanguyNed,

I am sorry for my late response. I have been out of town but I am back now so I will share this with my Recap specialist. I hope we can provide some suggestions or a solution shortly. Thank you for your patience.

[john.vellek]

Hi @TanguyNed

I am unable to duplicate the issues you are demonstrating. I believe that the density of your point cloud in conjunction with your graphics card are likely the reasons.

I am still waiting to hear back from my specialist on this to see if he can determine what is going on. Thanks for your patience

[john.vellek]

Hi @TanguyNed,

I talked to my specialist and he agreed with me that your point cloud is very dense. Neither of us could duplicate your issues but he suggested that you might clean out the cache in your DOL-DE-BRETAGNE Rue des Ponts Support folder.

 Then reload it into AutoCAD to see if the problem persists.

[john.vellek]

Hi @TanguyNed,

I am checking back to see if my post helped you with your problem or if you need additional assistance or information. Please add a post with how you decide to proceed and your results so other Community members may benefit.

Please hit the Accept as Solution button if my post fully solves your issue or answers your question.

[TanguyNed]

Sorry I didn't answer sooner, I'm frequently outside the office doing field work.

So I tried creating a new Recap project from the same scans, this time activating a decimation grid of 2.5 cm. The total number of points went from 103M down to 21M. Surely that's not a very dense point cloud anymore, but I still have the issue.

Also tried deleting the "Temporary Cache Files" folder, without result.

About the graphics card, shouldn't my Quadro K4200 be qualified enough ?

[john.vellek]

Hi @TanguyNed,

Let's take a closer look at your graphics driver. I found this one on Nvidia's site that is rather new. Note, they also recommend a software update from Dell at the bottom of the page (if that applies to your environment).

Please install this driver and report back if anything has changed.

[TanguyNed]

Thank you for your patience. I installed the driver you suggested (375.86) without result. I don't have a Dell.

[TanguyNed]

Update : Autodesk Customer Support contacted me. They were able to reproduce the glitch, but unable to solve it, so the issue has been forwarded to the development team. Wait and see.

[mika_jahkola]

Any progress on this issue?

I have the same problem  with every point cloud that I have inserted into Autocad.

Three different computers with different hardware, Autocad 2017 and Autocad 2018.

From a distance the point cloud looks OK but when zooming in suddenly you see duplicate features, or some features disappear.

Sometimes they reappear when zooming further in.

Viewed in Recap or Cloudcompare, the point clouds look normal.

[Alfred.NESWADBA]

Hi,

>> From a distance the point cloud looks OK but when zooming in

>> suddenly you see duplicate features

Try to change to a different graphic card driver (turning off hardware acceleration does not help as you then would not see the point-cloud at all).

(which graphc card do you use? start command _GRAPHICSCONFIG and show us the screenshot)

A usual attempt: make sure you have the latest AutoCAD updates installed (or start command _ABOUT and show us a screenshot from that dialog).

- alfred -

[mika_jahkola]

I collected a series a screen shots with comments in the attached word document.

The problem appears to be that individual scans are painted in the wrong place when zooming closer, or when panning a zoomed-in view.

The workaround to the problem is to export the point cloud from Recap as a single scan and load that into Autocad.

Obviously then you lose the ability to single out scans inside Autocad.

My hardware and software configuration is at the end of the document.

The problem does not seem to be tied to this particular machine and software.
More or less the same phenomenon is seen on our two other machines running Autocad 2017 or Autocad 2018.

All have Nvidia Geforce graphics cards: GTX 650, 960, and 1060.

[Alfred.NESWADBA]

Hi,

>> The workaround to the problem is to export the point cloud from

>> Recap as a single scan

Do I understand this correct: are the "doubled displayed" parts from different scanner positions? So turning off one of the scan-positions reduces the doubled display?

I would also tr the same in ReCap, because in ReCap the points could also be there, but it looks more "distributed" so you don't see the difference like in AutoCAD differentiated between light white and dark grey. Compare the critical scanner-positions.

- alfred -

[mika_jahkola]

Yes, each ghost image is a real scan from a particular station.