Tk_GetPixels(3) Tk Library Procedures Tk_GetPixels(3)______________________________________________________________________________NAME
Tk_GetPixels, Tk_GetScreenMM - translate between strings and screen
units
SYNOPSIS
#include <tk.h>
int
Tk_GetPixels(interp, tkwin, string, intPtr)
int
Tk_GetScreenMM(interp, tkwin, string, doublePtr)
ARGUMENTS
Tcl_Interp *interp (in) Interpreter to use for error report‐
ing.
Tk_Window tkwin (in) Window whose screen geometry deter‐
mines the conversion between absolute
units and pixels.
char *string (in) String that specifies a distance on
the screen.
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.
_________________________________________________________________DESCRIPTION
These two procedures take as argument a specification of distance on
the screen (string) and compute the corresponding distance either in
integer pixels or floating-point millimeters. In either case, 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_GetPixels converts string to the nearest even number of pixels and
stores that value at *intPtr. Tk_GetScreenMM converts string to mil‐
limeters and stores the double-precision floating-point result at *dou‐
blePtr.
Both procedures return TCL_OK under normal circumstances. If an error
occurs (e.g. string contains a number followed by a character that
isn't one of the ones above) then TCL_ERROR is returned and an error
message is left in interp->result.
KEYWORDS
centimeters, convert, inches, millimeters, pixels, points, screen units
TkTk_GetPixels(3)
