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0028640Community[OCCT] OCCT:Modeling Algorithmspublic2017-04-07 12:512019-08-12 16:43
devocctgp 
msv 
normalminor 
newopen 
 
[OCCT] 7.5.0* 
bugs modalg_7 bug28640
0028640: BRepBuilderAPI_Transform build invalid shape
BRepBuilderAPI_Transform mirror a shape generates invalid shape
gp_Trsf _mirror_trsf;
_mirror_trsf.SetMirror(gp_Ax2(gp_Pnt(0, 0, 0), gp_Dir(1, 0, 0)));

_shape = BRepBuilderAPI_Transform(_origin_shape, _mirror_trsf)

## Draw script ##
restore origin_copy.brep a
tmirror a 0 0 0 1 0 0
checkshape a
No tags attached.
png error.png (76,379) 2017-04-07 12:51
https://tracker.dev.opencascade.org/
? mirror.brep (4,372,559) 2017-04-07 12:55
https://tracker.dev.opencascade.org/
zip origin.zip (3,336,581) 2017-04-07 12:56
https://tracker.dev.opencascade.org/
? origin_copy.brep (2,033,617) 2017-04-07 16:09
https://tracker.dev.opencascade.org/
Issue History
2017-04-07 12:51devocctgpNew Issue
2017-04-07 12:51devocctgpAssigned To => msv
2017-04-07 12:51devocctgpFile Added: error.png
2017-04-07 12:55devocctgpFile Added: mirror.brep
2017-04-07 12:56devocctgpFile Added: origin.zip
2017-04-07 12:57devocctgpNote Added: 0065023
2017-04-07 12:58devocctgpNote Edited: 0065023bug_revision_view_page.php?bugnote_id=65023#r16369
2017-04-07 16:09msvFile Added: origin_copy.brep
2017-04-07 16:15msvNote Added: 0065040
2017-04-07 16:22msvSteps to Reproduce Updatedbug_revision_view_page.php?rev_id=16374#r16374
2017-04-08 21:44devocctgpNote Added: 0065068
2017-07-21 11:22msvTarget Version7.2.0 => 7.3.0
2017-09-01 15:03mkvTest case number => bugs modalg_7 bug28640
2017-09-01 15:03mkvNote Added: 0070136
2017-12-05 16:59msvTarget Version7.3.0 => 7.4.0
2019-08-12 16:43msvTarget Version7.4.0 => 7.5.0*

Notes
(0065023)
devocctgp   
2017-04-07 12:57   
(edited on: 2017-04-07 12:58)
the origin brep file is lager than the limitation. so i zipped it !

and note the origin brep is about twice large as the mirror brep

(0065040)
msv   
2017-04-07 16:15   
The size of origin shape is explained by redundant data in edges of the shape. The edges contain pogygons and triangulations not relevant to the faces of this shape. Transformation algorithm creates new edges and takes only relevant data.
The same origin shape without garbage can be got by deep copying it with BRepBuilderAPI_Copy algorithm. The Draw command 'tcopy' does it. I have attached such copy of origin. Now mirror creates a shape with the same file size.

I admit that the bug is reproduced. The mirrored shape does not pass the check by shape checker. I have put the draw script in steps to reproduce.
(0065068)
devocctgp   
2017-04-08 21:44   
dear msv,

after your explain, i understand the difference of size.

so let's fix the mirror bug.
(0070136)
mkv   
2017-09-01 15:03   
Problem described in issue is reproduced on current state of OCCT.