[Python API] Segfault when creating RenderJob on shallow copy of a scene

[eliemichel]

I am following section 13.2.7 of the manual in order to render animation frames on different machines, and in particular creates a so called shallow copy of the scene using newScene = Scene(scene), but whenever I create a render job on it, it crashes.

Steps to reproduce

Open a Python session and run:

import mitsuba
from mitsuba.core import *
from mitsuba.render import Scene, SceneHandler, RenderQueue, RenderJob
scene = SceneHandler.loadScene('scene.xml'))
scheduler = Scheduler.getInstance()
scheduler.registerWorker(LocalWorker(0, 'worker'))
scheduler.start()
queue = RenderQueue()
job = RenderJob('jobName', Scene(scene), queue)

The last line raises a segfault with the following backtrace:

(gdb) bt
#0  0x00007ffff5b419b3 in mitsuba::RenderJob::RenderJob(std::string const&, mitsuba::Scene*, mitsuba::RenderQueue*, int, int, int, bool, bool) ()
   from /cal/homes/emichel/src/mitsuba/build/binaries/libmitsuba-render.so
#1  0x00007ffff64cec88 in boost::python::objects::make_holder<3>::apply<boost::python::objects::pointer_holder<mitsuba::ref<mitsuba::RenderJob>, mitsuba::RenderJob>, boost::mpl::joint_view<boost::python::detail::drop1<boost::python::detail::type_list<std::string const&, mitsuba::Scene*, mitsuba::RenderQueue*, boost::python::optional<int, int, int, bool, bool, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_>, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_> >, boost::python::optional<int, int, int, bool, bool, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_, mpl_::void_> > >::execute(_object*, std::string const&, mitsuba::Scene*, mitsuba::RenderQueue*) ()
   from /cal/homes/emichel/src/mitsuba/build/binaries/python/mitsuba.so
#2  0x00007ffff64f6c26 in boost::python::objects::caller_py_function_impl<boost::python::detail::caller<void (*)(_object*, std::string const&, mitsuba::Scene*, mitsuba::RenderQueue*), boost::python::default_call_policies, boost::mpl::vector5<void, _object*, std::string const&, mitsuba::Scene*, mitsuba::RenderQueue*> > >::operator()(_object*, _object*) ()
   from /cal/homes/emichel/src/mitsuba/build/binaries/python/mitsuba.so
#3  0x00007ffff54a60ed in operator() (kw=0x0,
    args=(<RenderJob at remote 0x7ffff6ce2fc8>, 'jobName', <Scene at remote 0x7ffff6ce2f70>, <RenderQueue at remote 0x7ffff6ce2f18>), this=0xc0ffb0) at ./boost/python/object/py_function.hpp:143
#4  boost::python::objects::function::call (this=0xc0ffa0,
    args=(<RenderJob at remote 0x7ffff6ce2fc8>, 'jobName', <Scene at remote 0x7ffff6ce2f70>, <RenderQueue at remote 0x7ffff6ce2f18>), keywords=0x0) at libs/python/src/object/function.cpp:226
#5  0x00007ffff54a6308 in operator() (this=<optimized out>)
    at libs/python/src/object/function.cpp:585
#6  boost::detail::function::void_function_ref_invoker0<boost::python::objects::(anonymous namespace)::bind_return, void>::invoke (function_obj_ptr=...) at ./boost/function/function_template.hpp:188
#7  0x00007ffff54b0793 in operator() (this=0x7fffffffdc90)
    at ./boost/function/function_template.hpp:767
#8  boost::python::handle_exception_impl (f=...) at libs/python/src/errors.cpp:25
#9  0x00007ffff54a4ae9 in handle_exception<boost::python::objects::(anonymous namespace)::bind_return> (f=...) at ./boost/python/errors.hpp:29
#10 boost::python::objects::function_call (func=<optimized out>, args=<optimized out>,
    kw=<optimized out>) at libs/python/src/object/function.cpp:626
#11 0x0000000000502ab8 in PyObject_Call (kw=<optimized out>, arg=<optimized out>,
    func=<optimized out>) at ../Objects/abstract.c:2529
#12 instancemethod_call.lto_priv () at ../Objects/classobject.c:2602
#13 0x0000000000501afa in PyObject_Call (kw=0x0,
    arg=('jobName', <Scene at remote 0x7ffff6ce2f70>, <RenderQueue at remote 0x7ffff6ce2f18>),
    func=<instancemethod at remote 0x7ffff7f58b90>) at ../Objects/abstract.c:2529
#14 slot_tp_init.lto_priv () at ../Objects/typeobject.c:5692
#15 0x00000000004b988b in type_call.lto_priv () at ../Objects/typeobject.c:745
#16 0x00000000004c9e8b in PyObject_Call (kw=<optimized out>, arg=<optimized out>,
    func=<optimized out>) at ../Objects/abstract.c:2529
#17 do_call (nk=<optimized out>, na=<optimized out>, pp_stack=<optimized out>,
    func=<optimized out>) at ../Python/ceval.c:4251
#18 call_function (oparg=<optimized out>, pp_stack=<optimized out>) at ../Python/ceval.c:4056
#19 PyEval_EvalFrameEx () at ../Python/ceval.c:2679
#20 0x00000000004c7a59 in PyEval_EvalCodeEx () at ../Python/ceval.c:3265
#21 0x000000000050160f in PyEval_EvalCode (
    locals={'InterpolatedSpectrum': <Boost.Python.class at remote 0xba5a10>, 'getPrivateMemoryUsage': <Boost.Python.function at remote 0xbfb6f0>, 'getTotalSystemMemory': <Boost.Python.function at remote 0xbfb760>, 'Point3i': <Boost.Python.class at remote 0xbd31e0>, 'SHRotation': <Boost.Python.class at remote 0xc03970>, 'NativeBuffer': <Boost.Python.class at remote 0xbafdc0>, 'sampleTEA': <Boost.Python.function at remote 0xbfbca0>, 'mitsuba': <module at remote 0x7ffff7ea9ad0>, 'radicalInverse2': <Boost.Python.function at remote 0xbfb990>, 'SceneHandler': <Boost.Python.class at remote 0xc0f120>, 'getHostName': <Boost.Python.function at remote 0xbfb680>, 'fresnelConductorExact': <Boost.Python.function at remote 0xbfb1b0>, 'Epsilon': <float at remote 0x9d66d0>, 'Object': <Boost.Python.class at remote 0xb95380>, 'StringVector': <Boost.Python.class at remote 0xb90ee0>, 'Scheduler': <Boost.Python.class at remote 0xbb9f80>, 'WorkProcessor': <Boost.Python.class at remote 0xbb6210>, 'MTS_VERSION': '0.5.0', 'getCoreCount': <Boost....(truncated),
    globals={'InterpolatedSpectrum': <Boost.Python.class at remote 0xba5a10>, 'getPrivateMemoryUsage': <Boost.Python.function at remote 0xbfb6f0>, 'getTotalSystemMemory': <Boost.Python.function at remote 0xbfb760>, 'Point3i': <Boost.Python.class at remote 0xbd31e0>, 'SHRotation': <Boost.Python.class---Type <return> to continue, or q <return> to quit---
 at remote 0xc03970>, 'NativeBuffer': <Boost.Python.class at remote 0xbafdc0>, 'sampleTEA': <Boost.Python.function at remote 0xbfbca0>, 'mitsuba': <module at remote 0x7ffff7ea9ad0>, 'radicalInverse2': <Boost.Python.function at remote 0xbfb990>, 'SceneHandler': <Boost.Python.class at remote 0xc0f120>, 'getHostName': <Boost.Python.function at remote 0xbfb680>, 'fresnelConductorExact': <Boost.Python.function at remote 0xbfb1b0>, 'Epsilon': <float at remote 0x9d66d0>, 'Object': <Boost.Python.class at remote 0xb95380>, 'StringVector': <Boost.Python.class at remote 0xb90ee0>, 'Scheduler': <Boost.Python.class at remote 0xbb9f80>, 'WorkProcessor': <Boost.Python.class at remote 0xbb6210>, 'MTS_VERSION': '0.5.0', 'getCoreCount': <Boost....(truncated), co=0x7ffff7eeaa30) at ../Python/ceval.c:667
#22 run_mod.lto_priv () at ../Python/pythonrun.c:1371
#23 0x00000000004495f2 in PyRun_InteractiveOneFlags (fp=0x0,
    fp@entry=0x7ffff72974e0 <_IO_2_1_stdin_>, filename=0x0, filename@entry=0x603d84 "<stdin>",
    flags=0x7fffffffe2e0) at ../Python/pythonrun.c:858
#24 0x000000000044941e in PyRun_InteractiveLoopFlags (fp=fp@entry=0x7ffff72974e0 <_IO_2_1_stdin_>,
    filename=filename@entry=0x603d84 "<stdin>", flags=flags@entry=0x7fffffffe2e0)
    at ../Python/pythonrun.c:778
#25 0x000000000042d405 in PyRun_AnyFileExFlags (fp=0x7ffff72974e0 <_IO_2_1_stdin_>,
    filename=<optimized out>, closeit=0, flags=0x7fffffffe2e0) at ../Python/pythonrun.c:747
#26 0x00000000004981cd in Py_Main () at ../Modules/main.c:640
#27 0x00007ffff6f12b45 in __libc_start_main (main=0x497c60 <main>, argc=1, argv=0x7fffffffe4a8,
    init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>,
    stack_end=0x7fffffffe498) at libc-start.c:287
#28 0x0000000000497b8b in _start ()

[FlorentinJ]

I came across the same problem.
Try adding a "newScene.configure()" after copying and before rendering, it solved the issue in my case.
I found this inside "scene.h" ( https://searchcode.com/codesearch/view/46787189/ ), I guess sometimes looking into the code can be helpful.