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diff --git a/static/plan9-4e/man2/scribble.2 b/static/plan9-4e/man2/scribble.2 new file mode 100644 index 00000000..6f394add --- /dev/null +++ b/static/plan9-4e/man2/scribble.2 @@ -0,0 +1,162 @@ +.TH SCRIBBLE 2 +.SH NAME +scribblealloc, +recognize \- character recognition +.SH SYNOPSIS +.PP +.EX +.ta 4n +4n +4n +4n +4n +4n +4n +4n +4n +4n +#include <u.h> +#include <libc.h> +#include <draw.h> +#include <scribble.h> + +Scribble *scribblealloc(void); +Rune recognize(Scribble *); +.EE +.SH DESCRIPTION +.PP +The scribble library implements simple character recognition. +All characters are drawn using a single stroke of the pen (mouse button 1) +as on a palmtop computer. +A reference card is in +.BR /sys/src/libscribble/quickref.gif . +.PP +The library is not really intended for standalone use. Its primary +use is by the scribble graphical control (see +.IR control (2)). +.PP +.B Scribblealloc +allocates and returns an appropriately initialized +.B Scribble +structure: +.IP +.EX +.ta 4n +4n +4n +4n +4n +4n +4n +4n +4n +4n +#define CS_LETTERS 0 +#define CS_DIGITS 1 +#define CS_PUNCTUATION 2 + +struct Scribble { + /* private state */ + Point *pt; + int ppasize; + Stroke ps; + Graffiti *graf; + int capsLock; + int puncShift; + int tmpShift; + int ctrlShift; + int curCharSet; +}; +.EE +.PP +This structure encodes the points making up the stroke +to be recognized, as well as the \f2character group\fP in which +the stroke should be searched. +.PP +There are three such groups: +.IR letters , +.IR digits , +and +.IR punctuation . +The current group is encoded in the +.B curCharSet +field of the +.B Scribble +structure. +Special strokes are recognized to switch between groups. +In addition, the charater recognized is influenced by +.I mode +parameters and modifies them. +These are identified by the +.BR capsLock , +.BR puncShift , +.BR tmpShift , +and +.B ctrlShift +fields of the +.B Scribble +structure. +When +.B puncShift +is non-zero, the character is recognized in the punctuation +character set. +Similarly, +when the character recognized is printable and +.B ctrlShift +is set, the associated control character is returned as if the +control key were depressed, +and when the character is a letter and +.B capsLock +or +.B tmpShift +is set, the upper-case version is returned. +The +.B puncShift +and +.B tmpShift +flags are turned off +once a character has been recognized; the others are left set. +.PP +The character to be recognized is encoded as an array of pen_points in the +.B ps +field. +To allow easy drawing of the stroke as it is drawn, +the +.I pt +and +.I ppasize +fields are available to the application code for storing an array +of points for a call to +.B poly +(see +.IR draw (2)). +.PP +.I Recognize +recognizes the character provided in the +.B ps +field of the +.B Scribble +structure; it +returns the rune or zero if nothing was recognized. +.SH FILES +.B /sys/src/libscribble/quickref.gif +serves as a quick reference card. +.PP +.B /sys/lib/scribble/classifiers +contains the stroke definitions. +.SH SOURCE +.B /sys/src/libscribble +.PP +This library is adapted from software reproduced by permission: +.PP +.B Graffiti.c +is based on the file +.B Scribble.c +copyrighted +by Keith Packard: +.IP +Copyright © 1999 Keith Packard +.PP +Permission to use, copy, modify, distribute, and sell this software and its +documentation for any purpose is hereby granted without fee, provided that +the above copyright notice appear in all copies and that both that +copyright notice and this permission notice appear in supporting +documentation, and that the name of Keith Packard not be used in +advertising or publicity pertaining to distribution of the software without +specific, written prior permission. Keith Packard makes no +representations about the suitability of this software for any purpose. It +is provided "as is" without express or implied warranty. +.PP +Portions of the software Copyright © 1994 by Sun Microsystems Computer Company. +.PP +Portions of the software Copyright © 2000 by Compaq Computer Corporation. +.SH SEE ALSO +.B Keyboard +and +.B prompter +in +.IR bitsyload (1), +.IR draw (2), +.IR control (2) |