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Show_Location

Functions

void Show_Location (float *x, float *y)
 

Detailed Description

Function Documentation

void Show_Location ( float *  x,
float *  y 
)

Returns the raw 2-D position that was indicated by the user.

Parameters
x- The 2-D location indicated by the user using a previously- enabled locater device. The lower-left extreme of the locater device will be returned as (-1, -1); the upper-right will be as (+1, +1). Passed by reference always. Returned to caller.
y-

DETAILS

Once a "location" event has reached the front of the event queue and become the current event—either by enabling location events and then calling Await_Event() , or by calling Get_Location() to do all the work—your program can ask for details about it. The basic detail of a location event is the location itself. Get_Location() and Show_Location() both return the same information to your program. Get_Location() is a high-level routine that does a series of actions. Show_Location() is a low-level routine whose only function is to extract one piece of information about an already-recorded event.

Use Location events and Show_Location() when you're only interested in raw position information. Use Selection events and Show_Selection() when you're interested in that position as it relates to your picture.

NOTES

The Show routines can be called repeatedly on the same current event without harm, if that's convenient to your program.

If the current event is not actually a location-type event, or if there is no current event, the system will complain upon a call to Show_Location() .

Show_Location() is not the same function as Show_Selection_Position() . Show Selection Position goes with "selection" events, not location events, and selection events differ in that the position information has been digested and related to a picture on a screen.

RESTRICTIONS

See Also
Show_Location_Source, Get_Location, Get_Selection, Show_Selection_Position, Await_Event, Enable_Location_Events, Requeue_Event.

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