Archived issue #0030149

BRepMesh_Delaun: free triangle is left in the mesh after cleanup of auxiliary items

CommunityOCCT:Meshclosed13 public notes

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Description

I have created a body in FreeCAD
(see the attached "Attachment 1 (STEP)" file).

When I open this file in an application that uses OpenCascade (e.g. FreeCAD),
the body is not rendered well.

Relevant files (FreeCAD-file, step-file, screenshot):

  http://matej-Author.net/tmp/open_cascade_bugreport_20180920/


I've placed relevant files

Steps to reproduce

stepread [locate_data_file Attachment 1 (STEP)] a *
incmesh a_1 1
tricheck a_1

Public activity

13 archived notes

Participants are labeled by their role within this record.

01Commenter 2
The same strange display happens also on my computer.

CATIA displays the STEP file without these two grey triangles shining through.
02Commenter 3
This is a regression since OCCT 6.7.0.
03Commenter 4
Branch [archived branch] has been created by Commenter 5.

[revision removed]


Detailed log of new commits:

Author: Commenter 5
Date: Mon Mar 4 13:16:18 2019 +0300

    0030149: BRepMesh_Delaun: free triangle is left in the mesh after cleanup of auxiliary items
    
    Added new method BRepMesh_Delaun::superCleanup() intended to remove all triangles over free links remaining connected to elements of super triangle.
04Commenter 4
Branch [archived branch] has been created by Commenter 5.

[revision removed]


Detailed log of new commits:

Author: Commenter 5
Date: Wed Mar 6 14:29:57 2019 +0300

    0030149: BRepMesh_Delaun: free triangle is left in the mesh after cleanup of auxiliary items
    
    Remove free triangles connected to triangles over nodes of super triangle.
05Commenter 4
Branch [archived branch] has been updated forcibly by Commenter 5.

[revision removed]
06Commenter 4
Branch [archived branch] has been updated forcibly by Commenter 5.

[revision removed]
07Commenter 5
Dear Mikhail,

could you please review the patch located in CR30149_1.

Test reports are available at:
http://occt-tests/CR30149-master-OAN-OCCT/Windows-64-VC14/diff_summary.html
http://occt-tests/CR30149-master-OAN-OCCT/Debian80-64/diff_summary.html
08Commenter 8
Update test mesh standard_shading U5.

Please explain the difference:
IMAGE bugs modalg_2 bug21060: bug21060.png differs
09Commenter 5
Mikhail,

"mesh standard_shading U5" has already been updated and put in the branch.

As for "bugs modalg_2 bug21060", it is shape with self-intersections, so any incorrect modification of incorrect use case if not sufficient, IMHO.

But generally, it seems that last modification just prevents removing of some triangles by removing of seed triangle.
10Commenter 10
Reviewed.
11Commenter 1
Combination -
OCCT branch : [archived branch]
master SHA - [revision removed]
[revision removed]
Products branch : [archived branch] SHA - [revision removed]
was compiled on Linux, MacOS and Windows platforms and tested in optimize mode.

Number of compiler warnings:
No new/fixed warnings

Regressions/Differences/Improvements:
No regressions/differences

CPU differences:
Debian80-64:
OCCT
Total CPU difference: 16566.540000000034 / 16562.049999999996 [+0.03%]
Products
Total CPU difference: 9075.800000000028 / 9082.700000000026 [-0.08%]
Windows-64-VC14:
OCCT
Total CPU difference: 17972.390625 / 17955.015625 [+0.10%]
Products
Total CPU difference: 10478.875 / 10469.015625 [+0.09%]

Image differences :
No differences that require special attention

Memory differences :
No differences that require special attention
12Commenter 4
Branch [archived branch] has been deleted by Participant.

[revision removed]
13Commenter 4
Branch [archived branch] has been deleted by Participant.

[revision removed]