In the May, 2012 update of the OpenGL 4.2 Specification, all APIs using the types GLclampf and GLclampd
were modified to use GLfloat and GLdouble, respectively, instead. Language was added to the Specification
requiring that these parameters be clamped, when required, at use time rather than at specification time.
This change allows specifying parameters in ranges appropriate for non-fixed-point framebuffers (integer
and floating-point formats). The change does not require any changes to user code calling these
functions, because the actual underlying types are identical, the behavior is externally unchanged, and
the header files continue to define the old types for compatibility with older code.