[Gambas-user] Does anyone have experience with gb.openGL and "Not an object"?

[Francis Payne]

I've got an interesting issue with the OpenGL component.

I've been experimenting with OpenGL by going through the NeHe tutorials
and the MD2Model example provided. The problem is that I sometimes get
an unexpected message of "Not an object" when GL tries to start.

The skeleton of the code is:


Public Sub GLArea1_open()

  Gl.ClearDepth(100.0)       ' Enables clearing of the depth buffer
  Glu.ClearColor(&H3398C3)   ' This will clear the background color to blue
  Gl.DepthFunc(Gl.LESS)      ' The type of depth test to do
  Gl.Enable(Gl.DEPTH_TEST)   ' Enables depth testing
  Gl.ShadeModel(Gl.SMOOTH)   ' Enables smooth color shading
  Gl.Viewport(0, 0, GLArea1.Width, GLArea1.Height)
  Gl.MatrixMode(Gl.PROJECTION)
  Gl.LoadIdentity()                     'Reset The Projection Matrix
  Glu.Perspective(45.0, GLArea1.w / GLArea1.Height, 0.1, 3000.0)  
'Calculate The Aspect Ratio Of The Window
  Glu.LookAt(0, 100, 120, 0, 0, -300, 0, 100, 0)
  Gl.MatrixMode(Gl.MODELVIEW)
 
 
End

'< OTHER CODE GOES HERE  >

Public Sub Button1_Click()

  GLArea1.visible = True

End

Let me emphasise that *this skel**eton code works without problems* ! It
just opens an opengl window in the Glarea.

The problem happens when the 'other code' gets inserted - but the other
code makes no reference to opengl or the GlArea and consists solely of
operations on unrelated things like manipulating arrays, working on
other controls, etc.

I won't post the other code here because there's about 300kb of it. But
I have gone through it to make sure there are no references that could
interfere with openGL.

So, fellow Gambas programmers.... I don't expect a specific solution,
but as a guide, what **sort** of issues generally cause OpenGl to return
"Not an object" when called ?

[System]
Gambas=3.5.2
OperatingSystem=Linux
Kernel=3.2.0-57-generic-pae
Architecture=x86
Distribution=Ubuntu 12.04 LTS
Desktop=KDE4
Theme=QGtk
Language=en_US.UTF-8
Memory=12108M
[Libraries]
Cairo=libcairo.so.2.11000.2
Curl=libcurl.so.4.2.0
DBus=libdbus-1.so.3.5.8
GStreamer=libgstreamer-0.10.so.0.30.0
GStreamer=libgstreamer-1.0.so.0.1.0
GTK+=libgtk-x11-2.0.so.0.2400.10
Poppler=libpoppler.so.19.0.0
Qt4=libQtCore.so.4.8.1
SDL=libSDL-1.2.so.0.11.3