glPassThrough -- place a marker in the feedback buffer
void glPassThrough(GLfloat token)
Specifies a marker value to be placed in the feedback buffer
following a GL_PASS_THROUGH_TOKEN.
Feedback is a GL render mode. The mode is selected by calling
with GL_FEEDBACK. When the GL is in feedback mode, no pixels are
produced by rasterization. Instead, information about primitives that would
have been rasterized is fed back to the application using the GL. See
for a description of the feedback buffer and the values in it.
glPassThrough inserts a user-defined marker in the feedback buffer when
it is executed in feedback mode. token is returned as if it were a
primitive; it is indicated with its own unique identifying value:
GL_PASS_THROUGH_TOKEN. The order of glPassThrough commands
with respect to the specification of graphics primitives is maintained.
glPassThrough is ignored if the GL is not in feedback mode.
GL_INVALID_OPERATION is generated if glPassThrough is called
between a call to glBegin and the
corresponding call to glEnd.
glGet with argument
back to the OpenGL index page
© 1995 Uwe Behrens. All rights reserved.