- NAME
- Tk_GetPixelsFromObj, Tk_GetPixels, Tk_GetMMFromObj, Tk_GetScreenMM, Tk_GetDoublePixelsFromObj — translate between strings and screen units
- SYNOPSIS
- #include <tk.h>
- int
- Tk_GetPixelsFromObj(interp, tkwin, objPtr, intPtr)
- int
- Tk_GetDoublePixelsFromObj(interp, tkwin, objPtr, doublePtr)
- int
- Tk_GetPixels(interp, tkwin, string, intPtr)
- int
- Tk_GetMMFromObj(interp, tkwin, objPtr, doublePtr)
- int
- Tk_GetScreenMM(interp, tkwin, string, doublePtr)
- ARGUMENTS
- DESCRIPTION
- <none>
- c
- i
- m
- p
- KEYWORDS
Tk_GetPixelsFromObj, Tk_GetPixels, Tk_GetMMFromObj, Tk_GetScreenMM, Tk_GetDoublePixelsFromObj — translate between strings and screen units
#include <tk.h>
int
Tk_GetPixelsFromObj(interp, tkwin, objPtr, intPtr)
int
Tk_GetDoublePixelsFromObj(interp, tkwin, objPtr, doublePtr)
int
Tk_GetPixels(interp, tkwin, string, intPtr)
int
Tk_GetMMFromObj(interp, tkwin, objPtr, doublePtr)
int
Tk_GetScreenMM(interp, tkwin, string, doublePtr)
- Tcl_Interp *interp (in)
-
Interpreter to use for error reporting.
- Tk_Window tkwin (in)
-
Window whose screen geometry determines the conversion between absolute
units and pixels.
- Tcl_Obj *objPtr (in/out)
-
String value specifies a distance on the screen;
internal rep will be modified to cache converted distance.
- const char *string (in)
-
Same as objPtr except specification of distance is passed as
a string.
- int *intPtr (out)
-
Pointer to location in which to store converted distance in pixels.
- double *doublePtr (out)
-
Pointer to location in which to store converted distance in millimeters.
These procedures take as argument a specification of distance on
the screen (objPtr or string) and compute the
corresponding distance either in integer pixels or floating-point millimeters.
In either case,
objPtr or string
specifies a screen distance as a
floating-point number followed by one of the following characters
that indicates units:
- <none>
-
The number specifies a distance in pixels.
- c
-
The number specifies a distance in centimeters on the screen.
- i
-
The number specifies a distance in inches on the screen.
- m
-
The number specifies a distance in millimeters on the screen.
- p
-
The number specifies a distance in printer's points (1/72 inch)
on the screen.
Tk_GetPixelsFromObj converts the value of objPtr to the
nearest even number of pixels and stores that value at *intPtr.
It returns TCL_OK under normal circumstances.
If an error occurs (e.g. objPtr contains a number followed
by a character that is not one of the ones above) then
TCL_ERROR is returned and an error message is left
in interp's result if interp is not NULL.
Tk_GetPixelsFromObj caches information about the return
value in objPtr, which speeds up future calls to
Tk_GetPixelsFromObj with the same objPtr.
Tk_GetDoublePixelsFromObj is identical to Tk_GetPixelsFromObj
except it returns a double not rounded to the nearest integer.
Tk_GetPixels is identical to Tk_GetPixelsFromObj except
that the screen distance is specified with a string instead
of an object. This prevents Tk_GetPixels from caching the
return value, so Tk_GetPixels is less efficient than
Tk_GetPixelsFromObj.
Tk_GetMMFromObj and Tk_GetScreenMM are similar to
Tk_GetPixelsFromObj and Tk_GetPixels (respectively) except
that they convert the screen distance to millimeters and
store a double-precision floating-point result at *doublePtr.
centimeters, convert, inches, millimeters, pixels, points, screen units
Copyright © 1990 The Regents of the University of California.
Copyright © 1994-1998 Sun Microsystems, Inc.