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author | William Joye <wjoye@cfa.harvard.edu> | 2019-07-31 17:58:33 (GMT) |
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committer | William Joye <wjoye@cfa.harvard.edu> | 2019-07-31 17:58:33 (GMT) |
commit | 31ea2092cd64f21068bdca467639237ca3cab2bd (patch) | |
tree | 8330b605eef4885855552ad7d301fb1c447796cd /tk8.6/doc/GetPixels.3 | |
parent | de0c57b4383a4d7ced5058c2c50580a0f4ba5477 (diff) | |
download | blt-31ea2092cd64f21068bdca467639237ca3cab2bd.zip blt-31ea2092cd64f21068bdca467639237ca3cab2bd.tar.gz blt-31ea2092cd64f21068bdca467639237ca3cab2bd.tar.bz2 |
upgrade tcl/tk 8.6.10
Diffstat (limited to 'tk8.6/doc/GetPixels.3')
-rw-r--r-- | tk8.6/doc/GetPixels.3 | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/tk8.6/doc/GetPixels.3 b/tk8.6/doc/GetPixels.3 new file mode 100644 index 0000000..e7a9043 --- /dev/null +++ b/tk8.6/doc/GetPixels.3 @@ -0,0 +1,95 @@ +'\" +'\" Copyright (c) 1990 The Regents of the University of California. +'\" Copyright (c) 1994-1998 Sun Microsystems, Inc. +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +.TH Tk_GetPixelsFromObj 3 8.1 Tk "Tk Library Procedures" +.so man.macros +.BS +.SH NAME +Tk_GetPixelsFromObj, Tk_GetPixels, Tk_GetMMFromObj, Tk_GetScreenMM \- translate between strings and screen units +.SH SYNOPSIS +.nf +\fB#include <tk.h>\fR +.sp +int +\fBTk_GetPixelsFromObj(\fIinterp, tkwin, objPtr, intPtr\fB)\fR +.sp +int +\fBTk_GetPixels(\fIinterp, tkwin, string, intPtr\fB)\fR +.sp +int +\fBTk_GetMMFromObj(\fIinterp, tkwin, objPtr, doublePtr\fB)\fR +.sp +int +\fBTk_GetScreenMM(\fIinterp, tkwin, string, doublePtr\fB)\fR +.SH ARGUMENTS +.AS "Tcl_Interp" *joinPtr +.AP Tcl_Interp *interp in +Interpreter to use for error reporting. +.AP Tk_Window tkwin in +Window whose screen geometry determines the conversion between absolute +units and pixels. +.AP Tcl_Obj *objPtr in/out +String value specifies a distance on the screen; +internal rep will be modified to cache converted distance. +.AP "const char" *string in +Same as \fIobjPtr\fR except specification of distance is passed as +a string. +.AP int *intPtr out +Pointer to location in which to store converted distance in pixels. +.AP double *doublePtr out +Pointer to location in which to store converted distance in millimeters. +.BE +.SH DESCRIPTION +.PP +These procedures take as argument a specification of distance on +the screen (\fIobjPtr\fR or \fIstring\fR) and compute the +corresponding distance either in integer pixels or floating-point millimeters. +In either case, +\fIobjPtr\fR or \fIstring\fR +specifies a screen distance as a +floating-point number followed by one of the following characters +that indicates units: +.TP +<none> +The number specifies a distance in pixels. +.TP +\fBc\fR +The number specifies a distance in centimeters on the screen. +.TP +\fBi\fR +The number specifies a distance in inches on the screen. +.TP +\fBm\fR +The number specifies a distance in millimeters on the screen. +.TP +\fBp\fR +The number specifies a distance in printer's points (1/72 inch) +on the screen. +.PP +\fBTk_GetPixelsFromObj\fR converts the value of \fIobjPtr\fR to the +nearest even number of pixels and stores that value at \fI*intPtr\fR. +It returns \fBTCL_OK\fR under normal circumstances. +If an error occurs (e.g. \fIobjPtr\fR contains a number followed +by a character that is not one of the ones above) then +\fBTCL_ERROR\fR is returned and an error message is left +in \fIinterp\fR's result if \fIinterp\fR is not NULL. +\fBTk_GetPixelsFromObj\fR caches information about the return +value in \fIobjPtr\fR, which speeds up future calls to +\fBTk_GetPixelsFromObj\fR with the same \fIobjPtr\fR. +.PP +\fBTk_GetPixels\fR is identical to \fBTk_GetPixelsFromObj\fR except +that the screen distance is specified with a string instead +of an object. This prevents \fBTk_GetPixels\fR from caching the +return value, so \fBTk_GetPixels\fR is less efficient than +\fBTk_GetPixelsFromObj\fR. +.PP +\fBTk_GetMMFromObj\fR and \fBTk_GetScreenMM\fR are similar to +\fBTk_GetPixelsFromObj\fR and \fBTk_GetPixels\fR (respectively) except +that they convert the screen distance to millimeters and +store a double-precision floating-point result at \fI*doublePtr\fR. +.SH KEYWORDS +centimeters, convert, inches, millimeters, pixels, points, screen units |