random blue lines on model

[Matt Morris]

Hi guys, 

I have random blue lines appearing in my viewport from geometry, though not necessarily connected to points. They are totally unselectable and visible in any component selection mode. Quite often reloading the scene will make them disappear, and they're not showing up in render region. I'm guessing graphical glitch but using quadro k4000, which is normally pretty reliable.

Anyone come across this?

soft 2012 sp1 64, win 7, areo on, nvidia driver 320.00

Cheers,

Matt

--
www.matinai.com

[Christopher]

Do you see the lines when you move the object, as if they flicker ?

::Christopher::

[Alan Fregtman]

I've not experienced that particular glitch but I've presenced many wtf moments throughout the years with OpenGL freaking out... meshes exploding, polygons disappearing, depth-sorting messing up, transparency bugs, flickering meshes, ... the list goes on.

Sometimes it can be drivers, but if driver switching doesn't seem to fix it, it could be the card itself gone bad or overheating. (I'm assuming these lines appear all the time and not for one particular scene.)

There could also be smurfs trapped behind your screen; have you checked with Gargamel?

ps: One time I thought I had a visual glitch and it turned out there was a pixel-sized spider stuck inside in my LCD panel: https://vimeo.com/24337760

[Matt Morris]

lol! Haven't come across that yet ;)

Changing the subdivision level also gets rid of these pesky blue lines, and they show on other computers here. Never come across it before now though. Still on 2012 sp0 actually, might just see if I can get sp1 rolled out at least...

--
www.matinai.com

[Steven Caron]

does it happen in all viewports? can you screen shot it?

maybe check your viewport visibility options, attributes tab, see if you have polymesh boundaries, hulls, or internal edges on?

[Matt Lind]

That’s usually a sign of geometry corruption.  We experienced more than we cared for on this production.

 

Sometimes the root of the problem is clusters which are not properly synchronized with the topology (eg: contain indices which do not exist on the topology, or vice versa).  Rebuilding the clusters can make the visual glitches go away, but the root of the problem will persist.  In other words, expect it to come back at some point.

 

Best bet is to rebuild the clusters, duplicate the object without history, then start a new scene as the gremlin is likely in the scene’s internal data which you do not have access to as a user.

 

This is assuming the problem is geometry corruption, of course.  We’ve experienced other causes too such as bugs in our shaders.

 

 

Matt

[Matt Morris]

It does happen in all viewports and with all component views, but is nothing that I can turn on or off with every available checkbox. In other words I don't think its something that xsi understands or catagorises. I'll try to screencap next time it happens. The geometry is coming from zbrush so there may be something in the import which isn't as it should be, I'm guessing it is something like geo corruption as matt says, but hoping it doesn't come back!

--
www.matinai.com

[Matt Lind]

A first step in diagnosing the problem is to triangulate the geometry.  If that clears up the problem, then the issue is likely the clusters.  The only solution to that problem is to export to file (such as .obj or other non-native format.  Don’t use .emdl or .xsi) and start in a fresh new scene.

[Tim Leydecker]

You can hit [+] once to see if the mesh�s faces are randomly disconnected,
that would also be indicated by lightblue lines, which in turn could be
hard to see (flicker) if there would have been a merge operation somewhere
earlier on a two meshes overlayed ontop of each other, resulting in most but
not all duplicated faces being merged.

A good way to check topo is to load the *.obj into Maya and check for
non-manifold geometry there, using the cleanup option to just select
those faces.

ZBrush can be a bitch when merging down subtools into one mesh, especially
when you had copies of your "hero" in the same tool for backup sake but don�t
realize there�s no vertex merging involved in Zbrush�s merging, it�s just a
"combine" or a "merge" with weld=0.

The same double faces could also happen in XSI of course.
You could try to select all edges/points and do a "weld boundary points/edges"
operation.

Or select one face and do a "island from selection" to see if there is something
astray "underneath" when you move the island out of the way.

In ZBrush, you could also check your import/export options for *.obj, there
is a chance you can re-import into ZBrush using an autoweld on import but
that would nuke your pointorder...


Cheers,

tim

On 20.06.2013 20:05, Matt Morris wrote:
> It does happen in all viewports and with all component views, but is nothing that I can turn on or off with every available checkbox. In other words I don't think its something
> that xsi understands or catagorises. I'll try to screencap next time it happens. The geometry is coming from zbrush so there may be something in the import which isn't as it should
> be, I'm guessing it is something like geo corruption as matt says, but hoping it doesn't come back!
>
>
>
>

> On 20 June 2013 18:47, Matt Lind <ml...@carbinestudios.com <mailto:ml...@carbinestudios.com>> wrote:
>
> That�s usually a sign of geometry corruption. We experienced more than we cared for on this production.____
>
> __ __

>
> Sometimes the root of the problem is clusters which are not properly synchronized with the topology (eg: contain indices which do not exist on the topology, or vice versa).

> Rebuilding the clusters can make the visual glitches go away, but the root of the problem will persist. In other words, expect it to come back at some point.____
>
> __ __
>
> Best bet is to rebuild the clusters, duplicate the object without history, then start a new scene as the gremlin is likely in the scene�s internal data which you do not have
> access to as a user.____
>
> __ __
>
> This is assuming the problem is geometry corruption, of course. We�ve experienced other causes too such as bugs in our shaders.____
>
> __ __
>
> __ __
>
> Matt____
>
> __ __
>
> __ __
>
> *From:*softimag...@listproc.autodesk.com <mailto:softimag...@listproc.autodesk.com> [mailto:softimag...@listproc.autodesk.com
> <mailto:softimag...@listproc.autodesk.com>] *On Behalf Of *Matt Morris
> *Sent:* Thursday, June 20, 2013 4:02 AM
> *To:* soft...@listproc.autodesk.com <mailto:soft...@listproc.autodesk.com>
> *Subject:* random blue lines on model____
>
> __ __
>
> Hi guys, ____
>
> __ __

>
> I have random blue lines appearing in my viewport from geometry, though not necessarily connected to points. They are totally unselectable and visible in any component
> selection mode. Quite often reloading the scene will make them disappear, and they're not showing up in render region. I'm guessing graphical glitch but using quadro k4000,

> which is normally pretty reliable.____
>
> __ __
>
> Anyone come across this?____
>
> __ __
>
> soft 2012 sp1 64, win 7, areo on, nvidia driver 320.00____
>
> __ __
>
> __ __
>
> Cheers,____
>
> Matt____
>
>
> ____
>
> __ __
>
> --
> www.matinai.com <http://www.matinai.com> ____
>
>
>
>
> --
> www.matinai.com <http://www.matinai.com>

[Tim Leydecker]

One more thing.

If you used "merge" to combine seperate pieces into one mesh, it easily
happens that you don�t hit "Inputs>delete" but keep them sitting there.

Hitting + wouldn�t show you much, except faintly flickering lightblue
lines where your previous borderedges where, now overlayed by the
newly created mesh.

Next time you rectangle select more things to merge, you can end up
mistakenly creating a mesh containing both the original inputs, the
previous merged object and the new stuff you added.

That�s nasty and hard to see if you don�t do massive polymodeling
on the new object which would result in moving some of the points
away from atop each other, making you aware of the problem.

Your best bet is to try the island selection first, making sure
the status line indicates you have only one poly selected to start off with.

Joey Ponthieux has a *.js that separates objects into their seperate shells,
it�s probably available on rray, too? You could try that, doesn�t harm and
is less convoluted than manually probing random faces for their island connections.