GPHIGS C FUNCTIONS - SET LIGHT SOURCE STATE

SET LIGHT SOURCE STATE

PSET_LIGHT_SOURCE_ST

CALL SEQUENCE

void pset_light_source_st(

const Pint_list	*act_list,	/* activation list	*/
const Pint_list	*deact_list	/* deactivation list	*/

TYPES

typedef struct {
	Pint	num_ints;	/* number of Pints in list	*/
	Pint	*ints;	/* list of integers	*/
} Pint_list;

PHIGS STATE

(PHOP,*,STOP,*)

EFFECT

The SET LIGHT SOURCE STATE element is inserted in the open structure after element pointer or replaces the element indicated by element pointer, depending on the edit mode value. Element pointer is updated and points to the SET LIGHT SOURCE STATE structure element. The values specified in the function are associated with the element.

When an element of this type is interpreted, the current light source state entry in the traversal state list is modified according to the two lists associated with the element: The entries in the activation list are added to the current light source state if they are not already in the state; the entries in the deactivation list are removed from the current light source state if they are in the state. The current light source state is used to determine the set of active light sources used when displaying subsequent output primitives. Each entry is an index of an active light source in a workstation light source table.

When an element of this type is interpreted, only those light source representations defined on a workstation are potentially active. Entries in the current light source state corresponding to undefined light sources are ignored.

The same light source index cannot exist in both the activation and the deactivation lists.

EXTENSION TO THE PHIGS STANDARD

If GPHIGS is in NRS mode, the effect of this function is different from the effect described in the standard.

In NRS mode, (see OPEN PIPE), the element is not stored in a structure. It is sent to the workstation on which the pipe is opened.

ERRORS

5: Ignoring function, function requires state (PHOP,*, STOP,*)
133: Ignoring function, one of the entries in the activation list or deactivation list is less than one
135: Ignoring function, the same entry exists in both the activation list and the deactivation list