GPHIGS C FUNCTIONS - PICK PATH LIST

PICK PATH LIST

PXPICK_PATH_LIST

CALL SEQUENCE

void pxpick_path_list(

Pint	ws_id,	/* workstation identifier	(input)	*/
Pint	pick_dev_num,	/* pick device number	(input)	*/
Ppoint	*point,	/* located point in DC	(input)	*/
Pstore	store,	/* handle to store object	(input)	*/
Pin_status	*status,	/* return status	(output)	*/
Pxpick_path_list	**pick_path_list	/* return pick path list	(output)	*/

TYPES

typedef enum {
	PIN_STATUS_NONE,
	PIN_STATUS_OK,
	PIN_STATUS_NO_IN
} Pin_status;

typedef struct {
	Pint	num_paths;
	Ppick_path	*paths
} Pxpick_path_list;

typedef struct {
	Pint	depth;
	Ppick_path_elem	*path_list;
} Ppick_path;

typedef struct {
	Pint	struct_id;
	Pint	pick_id;
	Pint	elem_pos;
} Ppick_path_elem;

PHIGS STATE

(PHOP,WSOP,*,*)

EFFECT

This function is similar to PICK WITHOUT INTERACTION but if the current pick method is set to PXPICK_ALL, it returns all the paths contained in the pick aperture whereas PICK WITHOUT INTERACTION returns only one path selected depending on the current pick method.

Use of this function overcomes the differences in concept between an event-driven model ( MOTIF ) and the classic sequential model required for the use of PHIGS input.

Use SET PICK METHOD to select the appropriate pick method.

The store object must be allocated by CREATE STORE before calling this function. Use DELETE STORE to free the memory allocated to store the list of path.

NOTES

If the DC point is obtained as the result of an X event, it is necessary, before sending it to the function, to transform from X device coordinates to GPHIGS device coordinates. The origin of an X window is located at upper-left corner while the origin of a GPHIGS workstation is located at the lower-left corner. It is, therefore, necessary to invert the Y values in the following manner :

point.y = window.height - ev.xbutton.y ;

where window.height is the height in pixels of the X window and ev.xbutton.y is the Y position acquired with the event.

ERRORS

3: Ignoring function, function requires state (PHOP, WSOP,*,*)
54: Ignoring function, the specified workstation is not open
60: Ignoring function, the specified workstation is not of category OUTIN
250: Ignoring function, the specified device is not available on the specified workstation