GNU/Linux |
RedHat 6.2(Zoot) |
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GetPixels(3) |
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Tk_GetPixels, Tk_GetScreenMM − translate between strings and screen units
#include <tk.h>
int
Tk_GetPixels(interp, tkwin, string,
intPtr)
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. | ||
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. |
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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 millimeters and stores the double-precision floating-point result at *doublePtr.
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.
centimeters, convert, inches, millimeters, pixels, points, screen units
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GetPixels(3) | ![]() |