[vtk-developers] wxVTKRenderWindowInteractor example (was Re: X Error of failed request: GLXBadDrawable)

[Mathieu Malaterre]

Here is a short wx example to demonstrate the issue:

1. You can hit the X limit pretty easily replacing
wxVTKRenderWindowInteractor with wxVTKRenderWindow (in which case each
renderwindow will creates its own X Display)

2. The issue I can still not work around can be reproduced using the
following python-wx script (*). Even using the complicated (ref Charl
Boath) finalization scheme it seems that something is not getting
clean up here. Could an opengl guru recommend a way to track down the
opengl call that might be leaked ?


Basically all I am doing is create enough widget on the first notebook
page, so that when user click on page 2:
-> I get rid of all widget from page 1
-> all widget defined on page 2 are getting created until we hit the
hardcoded limit

Thanks !
-Mathieu
Ps: you might have to tweak grid=(15,15) for your particular opengl driver

(*)
import wx

from vtk import *
# important to use wxVTKRenderWindowInteractor here since it implement
the wx.GetXDisplay() trick
from vtk.wx.wxVTKRenderWindowInteractor import wxVTKRenderWindowInteractor


class Page(wx.Panel):
    def __init__(self, parent):
        wx.Panel.__init__(self, parent)
        grid=(15,15)
        sizer = wx.GridSizer(rows=grid[0], cols=grid[1], hgap=1, vgap=1)
        n = grid[0]*grid[1]

        sphere = vtkSphereSource()
        sphereMapper = vtkPolyDataMapper()
        sphereMapper.SetInput(sphere.GetOutput())

        sphereActor = vtkActor()
        sphereActor.SetMapper(sphereMapper)

        self._wlist=[]
        for i in range(0,n):
          ren = vtkRenderer()
          ren.AddActor(sphereActor)
          renWin = wxVTKRenderWindowInteractor(self,-1, size=(10,10))
          self._wlist.append( renWin )
          renWin.GetRenderWindow().AddRenderer(ren)
          sizer.Add( renWin, 1, wx.EXPAND)

        self.SetSizer(sizer)

class MainFrame(wx.Frame):
    def __init__(self):
        wx.Frame.__init__(self, None, title="Simple Notebook Example")

        p = wx.Panel(self)
        nb = wx.Notebook(p)
        nb.Bind(wx.EVT_NOTEBOOK_PAGE_CHANGED,  self.MyPageChanged,id=nb.GetId())

        self._page1 = Page(nb)
        self._page2 = Page(nb)

        nb.AddPage(self._page1, "Page 1")
        nb.AddPage(self._page2, "Page 2")

        sizer = wx.BoxSizer()
        sizer.Add(nb, 1, wx.EXPAND)
        p.SetSizer(sizer)

    def MyPageChanged(self,event=None):
        # We should first Finalize the old ones:
        print event.GetOldSelection()
        if event.GetOldSelection() == 0:
          for w in self._page1._wlist:
            renderers = w.GetRenderWindow().GetRenderers()
            numRenderers = renderers.GetNumberOfItems()
            renderers.InitTraversal()
            for i in range(0,numRenderers):
              w.GetRenderWindow().RemoveRenderer(renderers.GetNextItem())
            w.GetRenderWindow().Finalize()
            w.SetRenderWindow(None)
            del w

        event.Skip()

if __name__ == "__main__":
    app = wx.App()
    MainFrame().Show()
    app.MainLoop()


On Thu, Jun 26, 2008 at 4:55 PM, Mathieu Malaterre
<mathieu.malaterre at gmail.com> wrote:
> Hello there,
>
>   I am currently stuck on the following problem: when creating a lot
> of vtkRenderWindow (vtkXOpenGLRenderWindow in my case), there are two
> issues:
>
> 1. X has a limited number of Display. And you get an error like that:
>
> ...
> Xlib: connection to ":0.0" refused by server
> Xlib: Maximum number of clients reached
> ERROR: In /home/mmalaterre/Projects/VTK52/Rendering/vtkXOpenGLRenderWindow.cxx,
> line 1592
> vtkXOpenGLRenderWindow (0x2494140): bad X server connection. DISPLAY=:0
> ...
>
>  This can easily be worked around by reusing the same DisplayId for
> all your vtkRenderWindow (see SetDisplayId/GetDisplayId).
>
> 2. Once you get pass the first problem, it seem that OpenGL (or nvidia
> implementation in my case) has also a limited number of available
> context. So when creating a lot of vtkRenderWindow you get:
>
> ...
> The error was 'GLXBadDrawable'.
>  (Details: serial 403 error_code 158 request_code 143 minor_code 5)
>  (Note to programmers: normally, X errors are reported asynchronously;
>   that is, you will receive the error a while after causing it.
>   To debug your program, run it with the --sync command line
>   option to change this behavior. You can then get a meaningful
>   backtrace from your debugger if you break on the gdk_x_error() function.)
> ...
>
>  I have not been able to work around this issue. Has anyone deal with
> this before ? Is there a solution or at least a work around ?
>
> Thanks for suggestions !
> --
> Mathieu
> Ps: at least on my machine it seems opengl context are leaked even
> after the process was aborted, I cannot even start glxinfo anymore:
>
>
> $ glxinfo
> name of display: :0.0
> X Error of failed request:  GLXBadDrawable
>  Major opcode of failed request:  143 (GLX)
>  Minor opcode of failed request:  5 (X_GLXMakeCurrent)
>  Serial number of failed request:  18
>  Current serial number in output stream:  18
>



-- 
Mathieu