[solved] OpenGL: Could not find FB config.

[Ocye]

I use LazOpenGLContext successfully for some time. But after one of the recent LCL updates, I get the mentioned error when the context becomes visible. The example runs perfectly. However, I don't do any advanced stuff. Just standard Gl and Glu. Any idea where to look for the problem?

Lazarus 1.1 r37618 FPC 2.6.0 x86_64-linux-qt (compile target is gtk2)
Linux version 3.3.8-1-ARCH (tobias@T-POWA-LX) (gcc version 4.7.0 20120505 (prerelease) (GCC) ) #1 SMP PREEMPT Tue Jun 5 15:20:32 CEST 2012

[Ocye]

It works if I replace changes in gdk_gl_context_share_new() with rev 37115. Is attrList[] really assigned to valid data?

Code: [Select]

{$IFDEF UseFPGLX}
  FBConfig: TGLXFBConfig;
  FBConfigs: PGLXFBConfig;
  FBConfigsCount: Integer;

  { Attributes to choose context with glXChooseFBConfig.
    Similar to Attr, but not exactly compatible. }
  AttrFB: Array[0..10] of integer = (
            GLX_X_RENDERABLE, 1 { true },
            GLX_RED_SIZE, 1,
            GLX_GREEN_SIZE, 1,
            GLX_BLUE_SIZE, 1,
      GLX_DOUBLEBUFFER, 1 { true },
      none);
{$ENDIF}
...
FBConfigs:=glXChooseFBConfig(dpy, DefaultScreen(dpy), AttrFB, FBConfigsCount);


[zamtmn]

Hi.
Perhaps this patch solves the problem?

[Ocye]

No, FBConfigsCount is still 0 (rev 37777 with patch).

[zamtmn]

I also get this error when dynamically creating OpenGLContext in OnCreate form handler. If moved it to OnShow all starts working

[User137]

My little game engine nxPascal has like forever now created LazOpenGLContext dynamically at FormCreate, but i use win32.

Is this gtk related, or are you creating it with nil owner?

[Ocye]

Is this gtk related, or are you creating it with nil owner?

function gdk_gl_context_share_new() is defined in GLGtkGlxContext which is switched on/off in OpenGLContext

Code: [Select]

{$IFDEF UseGtk2GLX}
  GLGtkGlxContext;
{$ENDIF}
{$IFDEF UseCarbonAGL}
  GLCarbonAGLContext;
{$ENDIF}
{$IFDEF UseWin32WGL}
  GLWin32WGLContext;
{$ENDIF}

As far as I remember it was/is a Gtk2 issue only.

The Gl context is created dynamically.

Code: [Select]

TScrabbleCube=class(TOpenGLControl)
public
  constructor Create(aOwner:TComponent);override;
end;

constructor TScrabbleCube.Create(aOwner: TComponent);
begin
  inherited Create(aOwner);
  Parent:=aOwner as TWinControl;
...

TMain.OnSomething()
  ScrabbleCube:=TScrabbleCube.Create(pn3D);

The code runs well with my patch.

[zamtmn]

http://bugs.freepascal.org/view.php?id=22868

[zamtmn]

Ocye
it work after rev38678?

[Ocye]

Yes, it works perfectly.
(tested with revision 38851)