OpenGL Programming Guide: The Official Guide to Learning OpenGL, Version 4.3, Eighth Edition

Transform Feedback Objects

The state required to represent transform feedback is encapsulated into a transform feedback object. This state includes the buffer objects that will be used for recording the captured vertex data, counters indicating how full each buffer object is, and state indicating whether transform feedback is currently active. A transform feedback object is created by reserving a transform feedback object name and then binding it to the transform feedback object binding point on the current context. To reserve transform feedback object names, call:

void glGenTransformFeedbacks(GLsizei n, GLuint * ids);

Reserves n names for transform feedback objects and places the reserved names in the array ids.

The parameter n specifies ...