Name

preq_loc − Prompts for input using the locator-class logical input device specified. 

Operating States: PHOP, WSOP, ∗, ∗
PHIGS standard function

Syntax

void preq_loc (
  Pint         wsid,      /∗ (I) Workstation identifier ∗/
  Pint         dev_num,   /∗ (I) Locator device number ∗/
  Pin_status  ∗status,    /∗ (O) Input status ∗/
  Pint        ∗view_ind,  /∗ (O) View index ∗/
  Ppoint      ∗loc_pos    /∗ (O) 2D locator position, in world
                                 coordinates ∗/
)

Data Structures

typedef enum {
    PIN_STATUS_NONE,    /∗ user performed a break action ∗/
    PIN_STATUS_OK,      /∗ user selected a locator position ∗/
    PIN_STATUS_NO_IN    /∗ not used by this function ∗/
} Pin_status;
typedef struct {
    Pfloat     x;    /∗ x coordinate ∗/
    Pfloat     y;    /∗ y coordinate ∗/
} Ppoint;

Description

preq_loc prompts you for input using the locator-class logical input device specified by the device number and the workstation identifier.  If the input status is PIN_STATUS_OK, this function returns the world coordinate point and view index of the view transformation Digital PHIGS uses to translate the normalized projection coordinate points to the world coordinate points.  See Getting Started with DEC PHIGS for more information about view indexes. 

Digital PHIGS uses the current workstation transformation to translate the device coordinate point to a normalized projection coordinate point. 

This function ignores the z-coordinate components and returns a two-dimensional result. 

See Also

pget_loc
pinit_loc
preq_loc3
psample_loc
pset_loc_mode
pset_view_tran_in_pri