GPHIGS C FUNCTIONS - REQUEST PICK

REQUEST PICK

PREQ_PICK

CALL SEQUENCE

void preq_pick(

Pint	ws_id,	/* workstation identifier	*/
Pint	pick_dev,	/* pick device number	*/
Pint	depth,	/* max.  depth of returned path	*/
Pin_status 	*status,	/* (out) input status	*/
Ppick_path	*pick	/* (out) pick path	*/

TYPES

typedef enum {
	PIN_STATUS_NONE, 
	PIN_STATUS_OK, 
	PIN_STATUS_NO_IN
} Pin_status;

typedef struct {
	Pint	depth;	/* pick path depth	*/
	Ppick_path_elem	*path_list;	/* pick path list	*/
} Ppick_path;

typedef struct {
	Pint	struct_id;	/* structure identifier	*/
	Pint	pick_id;	/* pick identifier	*/
	Pint	elem_pos;	/* element position	*/
} Ppick_path_elem;

PHIGS STATE

(PHOP, WSOP, *, *).

EFFECT

Request a graphic structure element by user action on the left mouse button of the active device pick_dev with the possibility of cancelling the input by activating the device break by clicking on the right button of the mouse. A third state is possible for the status variable when no graphic entity is detected.

Example:

/* Request pick on workstation number 1 using device number 1 */
	Pint ws_id,pick_dev,depth;
	Pin_status status;
	Ppick_path_elem elem[5] ;
	Ppick_path pick_path;
	.....
	ws_id = 1;
	pick_dev = 1;
	depth = 5;
	pick_path.path_list = elem;
	preq_pick(ws_id,pick_dev,depth,&status,&pick_path);
	......

ERRORS

3: Ignoring function, function requires state (PHOP, WSOP,*,*)
54: Ignoring function, the specified workstation is not open
61: Ignoring function, specified workstation is neither of category INPUT nor of category OUTIN
250: Ignoring function, the specified device is not available on the specified workstation
251: Ignoring function, the function requires the input device to be in REQUEST mode