cgIsParameterReferenced
Keywords: cgIsParameterReferenced, NVIDIA, NVIDIA Cg Toolkit, Cg Toolkit, Shader, Shader Programming, GPU Shader Programming, GPU Program

> ## Name

> cgIsParameterReferenced - determine if a program parameter is potentially referenced

> ## Synopsis

>     #include <Cg/cg.h>

>     CGbool cgIsParameterReferenced( CGparameter param );

> ## Parameters

> param
>   The handle of the parameter to check.

> ## Return Values

> Returns CG_TRUE if param is a program parameter and is potentially referenced by the program.

> Returns CG_FALSE otherwise.

> ## Description

> cgIsParameterReferenced returns CG_TRUE if param is a program parameter, and is potentially referenced (used) within the program. It otherwise returns CG_FALSE.

> Program parameters are those parameters associated directly with a CGprogram, whose handles are retrieved by calling, for example, cgGetNamedProgramParameter.

> The value returned by cgIsParameterReferenced is conservative, but not always exact. A return value of CG_TRUE indicates that the parameter may be used by its associated program. A return value of CG_FALSE indicates that the parameter is definintely not referenced by the program.

> If param is an aggregate program parameter (a struct or array), CG_TRUE is returned if any of param's children are potentially referenced by the program.

> If param is a leaf parameter and the return value is CG_FALSE, cgGetParameterResource may return CG_INVALID_VALUE for this parameter.

> ## Examples

> to-be-written

> ## Errors

> CG_INVALID_PARAM_HANDLE_ERROR is generated if param is not a valid parameter.

> ## History

> cgIsParameterReferenced was introduced in Cg 1.1.

> ## See Also

> cgGetNamedProgramParameter, cgIsParameterUsed, cgGetParameterResource