Comment 22 for bug 19890

On Fri, Apr 21, 2006 at 07:34:32PM +0200, Bill Allombert wrote:
> Once upgrading (only) freeglut3 to 2.4.0-5, I get
> freeglut (conquestgl): ERROR: Internal error <Visual with necessary
> capabilities not found> in function fgOpenWindow
> X Error of failed request: BadWindow (invalid Window parameter)
> Major opcode of failed request: 4 (X_DestroyWindow)
> Resource id in failed request: 0x0
> Serial number of failed request: 29
> Current serial number in output stream: 33
>
> Once upgrading (only) conquest-gl to 8.1.2-2 I get
>
> conquestgl: symbol lookup error: conquestgl: undefined symbol: dspInitData

After upgrading conquest-libs to 8.1.2-2 I get:

freeglut (conquestgl): ERROR: Internal error <Visual with necessary capabilities not found> in function fgOpenWindow
X Error of failed request: BadWindow (invalid Window parameter)
  Major opcode of failed request: 4 (X_DestroyWindow)
  Resource id in failed request: 0x0
  Serial number of failed request: 23
  Current serial number in output stream: 26

So it seems conquest-gl need a versionned dependency on conquest-libs
(or conquest-libs shlibdeps should be bumped) to allow for partial
upgrades.

The code before this error:
GL.c:962

  glutInit(argc, argv);
  glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA | GLUT_ALPHA);

  glutInitWindowPosition(0,0);

  glutInitWindowSize(dConf.initWidth, dConf.initHeight);

  dConf.mainw = glutCreateWindow(CONQUESTGL_NAME);

Removing GLUT_ALPHA from glutInitDisplayMode in this file allow to
bypass the error message and get a window. (I am not sure whether
conquestgl really work but it does not crash).

According to the OPENGL GLUT spec:

   GLUT_ALPHA
          Bit mask to select a window with an alpha component to the
          color buffer(s).

So Jamie, does the error means that my GL driver does not support
alpha transparency, or is it a bug in freeglut ?

You can try the testcase I attached.

Cheers,
--
Bill. <email address hidden>

Imagine a large red swirl here.