0001269: Parametr "tolerance" in "Create Mesh from geometry" work strange. - FreeCAD Tracker

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ID	Project	Category	View Status	Date Submitted	Last Update

0001269	FreeCAD	Feature	public	2013-10-10 21:18	2013-10-11 10:35

Reporter	imyrek	Assigned To	wmayer
Priority	normal	Severity	minor	Reproducibility	random
Status	closed	Resolution	fixed
Product Version	0.13
Fixed in Version	0.14

Summary	0001269: Parametr "tolerance" in "Create Mesh from geometry" work strange.
Description	Parameter "tolerance" in python scripting Part.Shape.tessellate(tolerance) and in GUI menu "Mesh Design" -> "Meshes" -> "Create Mesh from geometry" work strange. Sometime it work correct, and sometime FreeCAD use previous value of this parametr(or return previous Mesh?). Tested on: OS: "Fedora release 18 (Spherical Cow)" Platform: 64-bit Version: 0.13.$WCREV$ Python version: 2.7.3 Qt version: 4.8.4 Coin version: 2.5.0 SoQt version: 1.5.0 OCC version: 6.5.4 OS: Ubuntu 10.04.4 LTS Platform: 32-bit Version: 0.14.2509 (Git) Branch: master Hash: 7cecafefaa67298486f6538ab34389dd825e38ae Python version: 2.6.5 Qt version: 4.6.2 Coin version: 3.1.2 SoQt version: 1.4.2a OCC version: 6.3.0
Additional Information	Python 2.7.3 (default, Aug 9 2012, 17:23:57) [GCC 4.7.1 20120720 (Red Hat 4.7.1-5)] on linux2 (...) >>> testPart = FreeCAD.ActiveDocument.addObject("Part::Feature","TestPart") >>> testPart.Shape=Part.makeSphere(66) >>> testPart.Shape.tessellate(6)[1].__len__() 2406 >>> testPart.Shape.tessellate(5)[1].__len__() 2406 >>> testPart.Shape.tessellate(4)[1].__len__() 2406 >>> testPart.Shape.tessellate(1)[1].__len__() 2406 >>> testPart.Shape.tessellate(0.6)[1].__len__() 2556 >>> testPart.Shape.tessellate(0.4)[1].__len__() 3830 >>> testPart.Shape.tessellate(0.2)[1].__len__() 6896 >>> testPart.Shape.tessellate(0.1)[1].__len__() 12962 >>> testPart.Shape.tessellate(0.06)[1].__len__() 20178 >>> testPart.Shape.tessellate(0.1)[1].__len__() 12962 >>> testPart.Shape.tessellate(0.2)[1].__len__() 12962 >>> testPart.Shape.tessellate(0.4)[1].__len__() 12962 >>> testPart.Shape.tessellate(0.6)[1].__len__() 12962 >>> testPart.Shape.tessellate(1)[1].__len__() 12962 >>> testPart.Shape.tessellate(0.66)[1].__len__() 12962 >>> testPart.Shape=Part.makeSphere(66) >>> testPart.Shape.tessellate(0.66)[1].__len__() 2406 >>> testPart.Shape.tessellate(1)[1].__len__() 2406 >>> testPart.Shape.tessellate(0.01)[1].__len__() 98036 >>> >>> testPart.Shape.tessellate(0.1)[1].__len__() 98036 >>> testPart.Shape.tessellate(1)[1].__len__() 98036 >>>
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FreeCAD Information

wmayer 2013-10-11 10:15 administrator ~0003728	When tessellating a shape the mesh is kept internally because this is used for many algorithms like bounding box checks, boolean operations, ... If you tessellate a mesh with a certain tolerance then it overwrites the current mesh if it's finer (i.e. has more triangles). This means that if you again try to create a coarser mesh this will be rejected. So, this is totally comprehensible behaviour.

wmayer 2013-10-11 10:34 administrator ~0003729	There is now second but optional argument in tessellate(). False (default) means to keep the old triangulation amd True means to clear it. So, this snippet will show the behaviour you have expected: testPart = FreeCAD.ActiveDocument.addObject("Part::Feature","TestPart") testPart.Shape=Part.makeSphere(66) testPart.Shape.tessellate(6,True)[1].__len__() testPart.Shape.tessellate(5,True)[1].__len__() testPart.Shape.tessellate(4,True)[1].__len__() testPart.Shape.tessellate(1,True)[1].__len__() testPart.Shape.tessellate(0.6,True)[1].__len__() testPart.Shape.tessellate(0.4,True)[1].__len__() testPart.Shape.tessellate(0.2,True)[1].__len__() testPart.Shape.tessellate(0.1,True)[1].__len__() testPart.Shape.tessellate(0.06,True)[1].__len__() testPart.Shape.tessellate(0.1,True)[1].__len__() testPart.Shape.tessellate(0.2,True)[1].__len__() testPart.Shape.tessellate(0.4,True)[1].__len__() testPart.Shape.tessellate(0.6,True)[1].__len__() testPart.Shape.tessellate(1,True)[1].__len__() testPart.Shape.tessellate(0.66,True)[1].__len__() testPart.Shape=Part.makeSphere(66) testPart.Shape.tessellate(0.66,True)[1].__len__() testPart.Shape.tessellate(1,True)[1].__len__() testPart.Shape.tessellate(0.01,True)[1].__len__() testPart.Shape.tessellate(0.1,True)[1].__len__() testPart.Shape.tessellate(1,True)[1].__len__()

wmayer 2013-10-11 10:35 administrator ~0003730	git show e631be1

Date Modified	Username	Field	Change
2013-10-10 21:18	imyrek	New Issue
2013-10-11 10:15	wmayer	Note Added: 0003728
2013-10-11 10:32	wmayer	Assigned To	=> wmayer
2013-10-11 10:32	wmayer	Status	new => assigned
2013-10-11 10:32	wmayer	Category	Bug => Feature
2013-10-11 10:34	wmayer	Note Added: 0003729
2013-10-11 10:35	wmayer	Note Added: 0003730
2013-10-11 10:35	wmayer	Status	assigned => closed
2013-10-11 10:35	wmayer	Resolution	open => fixed
2013-10-11 10:35	wmayer	Fixed in Version	=> 0.14