problem of mentor example 10.1

[coin3d]

problem of mentor example 10.1

[looooo]

This is a fork from https://bitbucket.org/Coin3D/pivy/src. This fork only tries to add python3 compatibility. I haven't got a working soqt version, so I can't test this example right now. I will try to translate this example to quarter in the next days.

[cbjcbj]

Thank you for your reply. Hope everything gose well.

[looooo]

https://github.com/looooo/pivy/blob/master/examples/Mentor_quarter/10.1.addEventCB.py
this works for me.
Is the pivy from the ppa based on this fork? I think all freecad-ppa use the official pivy repository, but maybe I am wrong.

ps.: Didn't try the arrow up... So the crash also appears with quarter.

[cbjcbj]

I don't know the ppa well. I download the official coin source and cannot compile. And I install FreeCAD and find it contains pivy. Then I find your pivy project here. So If I want to install your pivy lib, do I just need to run the setup.py?

I alo test some mentor examples. Some of them will show warning messages (like 02.1), and some fails (like 10.3 and 10.6). I don't know if it is a bug of something else.

[looooo]

Thanks for your feedback,

If I want to install your pivy lib, do I just need to run the setup.py?

exactly:

To compile pivy run
python setup.py build

To install:
python setup.py install

But the problems will remain...

The problem with 10.1 is the scaling function. setting the scalefactror crashes the programm. I haven't investigated this, because with my branch I have found a strange problem with the callbacks...

FreeCAD has implemented it's own viewer. So I never had a look at the viewers provided by pivy (quarter, sogui). Maybe you can try to run the example within FreeCAD. Allthough the scaling problem will also remain.

[looooo]

finally I have found what caused the problem with my pivy version.
Here is the bt for the scaling problem:

#0 0x00007ffff7826418 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1 0x00007ffff782801a in __GI_abort () at abort.c:89
#2 0x00007ffff786872a in __libc_message (do_abort=do_abort@entry=2, fmt=fmt@entry=0x7ffff79816b0 "*** Error in `%s': %s: 0x%s ***\n")
at ../sysdeps/posix/libc_fatal.c:175
#3 0x00007ffff7870f4a in malloc_printerr (ar_ptr=, ptr=, str=0x7ffff797e48f "free(): invalid pointer",
action=3) at malloc.c:5007
#4 _int_free (av=, p=, have_lock=0) at malloc.c:3868
#5 0x00007ffff7874abc in __GI___libc_free (mem=) at malloc.c:2969
#6 0x00007fffeea05a04 in _wrap_delete_SbVec3f (args=) at pivy/coin_wrap.cpp:49974
#7 0x00000000004b0de3 in PyObject_Call ()
#8 0x00000000004b9362 in PyObject_CallFunctionObjArgs ()
#9 0x00007fffee76dd00 in SwigPyObject_dealloc (v=0x7fffef42aba0) at pivy/coin_wrap.cpp:1721
#10 0x00000000004fd546 in ?? ()
#11 0x00000000004d8d07 in ?? ()
#12 0x00000000004c9970 in PyEval_EvalFrameEx ()
#13 0x00000000004c22e5 in PyEval_EvalCodeEx ()
#14 0x00000000004de7fe in ?? ()
#15 0x00000000004b0de3 in PyObject_Call ()
#16 0x00000000004ce140 in PyEval_CallObjectWithKeywords ()
#17 0x00007fffee7d78b8 in SoEventPythonCallBack (userdata=0x7fffefdb37a0, node=) at pivy/coin_wrap.cpp:6898

[looooo]

• The error is somewhere in the __imul__ (*=) function of SfVec3f... I will have a look at this, but simply using a = a * b instead of a *= b should also work. See here: examples/Mentor/10.1.addEventCB.py#L68
• Another thing not working in this example is this examples/Mentor/10.1.addEventCB.py#L184.
  With quarter I added a callback function to redraw the scene when the selection changed: examples/Mentor_quarter/10.1.addEventCB.py#L193
• With my pivy branch callbacks have to be set to a variable in python. This way it's possible to delete a callback. This is done similarly in FreeCAD. The problem with my implementation is that the return value of addEventCallback(foo) has to be set to a variable in python. Otherwise the garbage collector will delete this object and the callback can't access the function. examples/Mentor_quarter/10.1.addEventCB.py#L119[done]

[cbjcbj]

Hi, I am still reading your code. If I have any though, I will tell you. Thank you.

[looooo]

I think this should be fixed