Did FC eat my keyboard ?

[wmayer]

I can understand that an app becomes more or less unresponsive when CPU-intensive tasks are running, but when it affects the whole desktop, it is a real problem.

But then it's a question of how much this is an OS issue or a DE issue.

When computing the surface a huge square matrix needs to be computed and the majority of time is taken to compute the coefficients while solving the equation system almost happens in no time. In order to speed this up the computation of the coefficients can be done multi-threaded and possibly this make the system unresponsive.

To test this go to https://github.com/FreeCAD/FreeCAD/blob ... .cpp#L1070 and change the 0 in line 1070 to 1 (or alternatively change line 1072). But then the algorithms takes noticeably longer to finish.

If this solves your issue we can add a parameter to control the behaviour.

However, if the problem is not related to this I see no chance that we could fix anything there.

[Chris_G]

Hi,
This change makes no difference.
So, this is probably an OS bug.
Thanks for the help.

[microelly2]

I have tested with my garden cloud (https://www.youtube.com/watch?v=xSsSJ0BzoFw).
The garden cloud is computed from a set of 20 points.

Get the elevation grid (point cloud with 12000 points)
with scipy interpolation requires 4 sec.

Then I used Reen to get the Nurbs.

No extra RAM was required.

Here the time results

phase 1 Point Cloud to ReverseEngineering.approxSurface
phase 2 surface to shape

degree 2/ pols 12
10 s (4 cpu)
20 s (1 cpu)

degree 2/ pols 14
18 s
60 s

degree2/ pols 16
49 s
555 s

In the first phase all 4 CPUs are on 100% and indeed the computer is "computing", nothing else can be done.
The 2nd phase - creating a shape from the nurbs object is very time consuming.
So the question for me is: When I should use the nurbs model and how I can postprocess it?

The best reslut I got with 14 pols.
In the picture

blue is the 12000 point cloud,
red the 16 pols face
green the 14 pols face.
The match of the 16 pols is good but there are some disturbances in the right lower picture.

The approximation is good but the runtime

[NormandC]

I can understand that an app becomes more or less unresponsive when CPU-intensive tasks are running, but when it affects the whole desktop, it is a real problem.

But then it's a question of how much this is an OS issue or a DE issue.

Chris_G hasn't mentioned his DE but spoke of Dolphin so he must be using KDE. I use GNOME/Unity. I guess this is an OS issue... We're both using 14.04 (but I plan on upgrading to 16.04 this summer)

[NormandC]

In this topic there is a file (the 3.3MB one) that locked up my keyboard while I was trying to post my reply. I had just attempted to edit the PartDesign Sweep...

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