Re: [PyOpenGL-Users] glGenLists returns 0

[Gary Herron]

Astan Chee wrote:

Hi,
Im trying to do glGenLists while a program is running and it keeps
returning 0 and whenever I try to do a glCallList, it fails with a
'invalid value' error.
Is this a known issue? why would my program give valid glGenList while
being initialized but not while it is running?

IIRC, this can happen if you call glGenLists *before* you create any
windows (or perhaps more accurately, before an OpenGL context has been
created).

Im using wx to create a new pygame thread that uses pyopengl. This is
the glGenList snippet:

dlBody = glGenLists(1)
glNewList(dlBody,GL_COMPILE)
SphereT = gluNewQuadric()
gluSphere(SphereT, 0.5, 32, 32)
gluQuadricNormals(SphereT, GLU_SMOOTH)
gluQuadricDrawStyle(SphereT, GLU_FILL)
glEndList()

and here is how I init:

glShadeModel(GL_SMOOTH)
glClearColor(0.0, 0.0, 0.0, 0.0)
glClearDepth(1.0)
glEnable(GL_DEPTH_TEST)
glDepthFunc(GL_LEQUAL)
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST)

glEnable (GL_LIGHT0)
glEnable (GL_LIGHTING)
glEnable(GL_TEXTURE_2D)

LightAmbient = ( (0., 0., 0., 0.,1.) )
glLightModelfv( GL_LIGHT_MODEL_AMBIENT, LightAmbient )

glEnable(GL_COLOR_MATERIAL)

glViewport(0, 0, width, height)
glMatrixMode(GL_PROJECTION)
glLoadIdentity()
gluPerspective(45, 1.0*width/height, 1.0, 10000.0)
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()