Cg Core Runtime API                          cgIsParameterUsed(3)



NAME
     cgIsParameterUsed - determine if a parameter is potentially
     used

SYNOPSIS
       #include 

       CGbool cgIsParameterUsed( CGparameter param,
                                 CGhandle container );


PARAMETERS
     param   The parameter to check.

     container
             Specifies the CGeffect, CGtechnique, CGpass,
             CGstateassignment, or CGprogram that may potentially
             use param.

RETURN VALUES
     Returns CGTRUE if param is potentially used by container.

     Returns CGFALSE otherwise.

DESCRIPTION
     cgIsParameterUsed returns CGTRUE if param is potentially
     used by the given container.  If param is a struct or array,
     CGTRUE is returned if any of its children are potentially
     used by container.  It otherwise returns CGFALSE.

     The value returned by cgIsParameterUsed is conservative, but
     not always exact.  A return value of CGTRUE indicates that
     the parameter may be used by container.  A return value of
     CGFALSE indicates that the parameter is definintely not
     used by container.

     The given param handle may reference a program parameter, an
     effect parameter, or a shared parameter.

     The container handle may reference a CGeffect, CGtechnique,
     CGpass, CGstateassignment, or CGprogram.

     If container is a CGprogram, CGTRUE is returned if any of
     the program's referenced parameters inherit their values
     directly or indirectly (due to parameter connections) from
     param.

     If container is a CGstateassignment, CGTRUE is returned if
     the right-hand side of the state assignment may directly or
     indirectly depend on the value of param.  If the state
     assignment involves a CGprogram, the program's parameters
     are also considered, as above.



Cg Toolkit 2.1            Last change:                          1






Cg Core Runtime API                          cgIsParameterUsed(3)



     If container is a CGpass, CGTRUE is returned if any of the
     pass' state assignments potentially use param.

     If container is a CGtechnique, CGTRUE is returned if any of
     the technqiue's passes potentially use param.

     If container is a CGeffect, CGTRUE is returned if any of
     the effect's techniques potentially use param.

EXAMPLES
     to-be-written

ERORS
     CGINVALIDPARAMHANDLEROR is generated if param is not a
     valid parameter, or if container is not the handle of a
     valid container.

HISTORY
     cgIsParameterUsed was introduced in Cg 1.4.

SEE ALSO
     cgIsParameterReferenced, cgConnectParameter

































Cg Toolkit 2.1            Last change:                          2