Dear DAVID Community,

As you are probably aware, the entire DAVID company, team and product range has been integrated into HP Inc.
This forum is now read-only. Relevant content has been migrated to HP and merged into HP's Support Forums on November 1, 2016.

To start new discussions for 3D Scanning, please register and post your new topic at the HP Support Forums

[Solved] Flipping Normals Orientation in FreeAlign-Mode

If you found a bug, please post it here and we will try to eleminate it as soon as possible.

[Solved] Flipping Normals Orientation in FreeAlign-Mode

Postby MagWeb » Sat Nov 30, 2013 2:09 am

Hi Sven,

found a little glitch.
Trying to show a methode to align scans of broken pieces using ContactPair I found that flipping the faces orientation (via RMB menue on ListOfScans) isn't regarded by the AlignTools (at least Free):
To align two broken pieces I've to invert the scan's normals of one piece to be a negative to the other surface.
Doing this within DAVID the inverted negative part is rendered mate - ok.
Exporting that part and opening it somwhere else shows it is actually inverted - ok.
Fusing the inverted part shows the weired behaviour that can be expected - ok.

But aligning does not care about the orientation as long as you do not save and reload the inverted part. Seems Align refers to the initial orientation all the time of a session.
If you load a inverted negative part it behaves inverted even if you flip it to positiv again.
Same for loading a positive part and inverting it to negative the opther way round.

Seems nobody is aware of this puzzle methode anymore despite of DAVIDs beginning :(
MagWeb
Moderator
 
Posts: 2499
Joined: Wed Jul 18, 2007 8:48 pm

Re: Flipping Normals Orientation in FreeAlign-Mode

Postby MagWeb » Sat Nov 30, 2013 2:31 am

Update:
Also a Fusion and switching back to show scans puts the things right and changes the behaviour.
MagWeb
Moderator
 
Posts: 2499
Joined: Wed Jul 18, 2007 8:48 pm

Re: Flipping Normals Orientation in FreeAlign-Mode

Postby Sven » Wed Dec 11, 2013 9:27 am

Thanks Gunter,
We will look into that!
Sven
User avatar
Sven
DAVID Developer
 
Posts: 1541
Joined: Mon Jan 22, 2007 8:59 am
Location: Braunschweig, Germany

Re: [InProgress] Flipping Normals Orientation in FreeAlign-M

Postby MagWeb » Wed Jan 01, 2014 1:04 pm

Just found:

this issue depends on the workflow (maybe somehow related to the Undo history?)

I load a set of 4 meshes scanned as single objects. These results shall be puzzled together. To do this right I've to invert all meshes but mesh1 (green) - (or only mesh1)
Doing this inversion immediately after loading them, I get an expected behaviour (using contact pairs):

InvertBug2.png


But trying some free alignment before inverting normals shows the faulty behaviour as described above:

InvertBug1.png


EDIT - Just to add:
Only the mesh that was aligned without inversion before (here: the yellow one) shows not-inverted behaviour. Blue and light blue still work as expected.
MagWeb
Moderator
 
Posts: 2499
Joined: Wed Jul 18, 2007 8:48 pm

Re: [InProgress] Flipping Normals Orientation in FreeAlign-M

Postby Sven » Mon Jan 06, 2014 8:23 pm

Thanks, Gunter!

I can reproduce the problem. Also I think I know why it happens: For alignment, we initialize a special data structure for each mesh. This takes time, so we do it only once, or when the mesh has changed (e.g. cleaning tool). Inverting the normals does change the mesh, but this change is not regarded -> no re-init -> wrong normals for alignment.

We'll repair it.

Sven
User avatar
Sven
DAVID Developer
 
Posts: 1541
Joined: Mon Jan 22, 2007 8:59 am
Location: Braunschweig, Germany

Re: [InProgress] Flipping Normals Orientation in FreeAlign-M

Postby Sven » Tue Jan 07, 2014 5:46 pm

Fixed for next release.
Sven
User avatar
Sven
DAVID Developer
 
Posts: 1541
Joined: Mon Jan 22, 2007 8:59 am
Location: Braunschweig, Germany

Re: [Fixed] Flipping Normals Orientation in FreeAlign-Mode

Postby MagWeb » Tue Jan 07, 2014 10:30 pm

Fine! :)
MagWeb
Moderator
 
Posts: 2499
Joined: Wed Jul 18, 2007 8:48 pm


Return to Bug Report

Who is online

Users browsing this forum: No registered users and 1 guest

cron