Provided by: libimage-base-bundle-perl_1.0.7-3.5_all bug

NAME

       Image::Xbm - Load, create, manipulate and save xbm image files.

SYNOPSIS

           use Image::Xbm ;

           my $j = Image::Xbm->new( -file, 'balArrow.xbm' ) ;

           my $i = Image::Xbm->new( -width => 10, -height => 16 ) ;

           my $h = $i->new ; # Copy of $i

           my $p = Image::Xbm->new_from_string( "###\n#-#\n###" ) ;

           my $q = $p->new_from_string( "H##", "#-#", "###" ) ;

           my $s = $q->serialse ; # Compresses a little too.
           my $t = Image::Xbm->new_from_serialsed( $s ) ;

           $i->xybit( 5, 8, 1 ) ;           # Set a bit
           print '1' if $i->xybit( 9, 3 ) ; # Get a bit
           print $i->xy( 4, 5 ) ;           # Will print black or white

           $i->vec( 24, 0 ) ;            # Set a bit using a vector offset
           print '1' if $i->vec( 24 ) ;  # Get a bit using a vector offset

           print $i->get( -width ) ;     # Get and set object and class attributes
           $i->set( -height, 15 ) ;

           $i->load( 'test.xbm' ) ;
           $i->save ;

           print "equal\n" if $i->is_equal( $j ) ;

           print $j->as_string ;

           #####-
           ###---
           ###---
           #--#--
           #---#-
           -----#

           print $j->as_binstring ;

           1111101110001110001001001000100000010000

       View an xbm file from the command line:

           % perl -MImage::Xbm -e'print Image::Xbm->new(-file,shift)->as_string' file

       Create an xbm file from the command line:

           % perl -MImage::Xbm -e'Image::Xbm->new_from_string("###\n#-#\n-#-")->save("test.xbm")'

DESCRIPTION

       This class module provides basic load, manipulate and save functionality for the xbm file
       format. It inherits from "Image::Base" which provides additional manipulation
       functionality, e.g. "new_from_image()". See the "Image::Base" pod for information on
       adding your own functionality to all the "Image::Base" derived classes.

   new()
           my $i = Image::Xbm->new( -file => 'test.xbm' ) ;
           my $j = Image::Xbm->new( -width => 12, -height => 18 ) ;
           my $k = $i->new ;

       We can create a new xbm image by reading in a file, or by creating an image from scratch
       (all the bits are unset by default), or by copying an image object that we created
       earlier.

       If we set "-file" then all the other arguments are ignored (since they're taken from the
       file). If we don't specify a file, "-width" and "-height" are mandatory.

       "-file"
           The name of the file to read when creating the image. May contain a full path.  This
           is also the default name used for "load"ing and "save"ing, though it can be overridden
           when you load or save.

       "-width"
           The width of the image; taken from the file or set when the object is created; read-
           only.

       "-height"
           The height of the image; taken from the file or set when the object is created; read-
           only.

       "-hotx"
           The x-coord of the image's hotspot; taken from the file or set when the object is
           created. Set to -1 if there is no hotspot.

       "-hoty"
           The y-coord of the image's hotspot; taken from the file or set when the object is
           created. Set to -1 if there is no hotspot.

       "-bits"
           The bit vector that stores the image; read-only.

   new_from_string()
           my $p = Image::Xbm->new_from_string( "###\n#-#\n###" ) ;
           my $q = $p->new_from_string( "H##", "#-#", "###" ) ;
           my $r = $p->new_from_string( $p->as_string ) ;

       Create a new bitmap from a string or from an array or list of strings. If you want to use
       different characters you can:

           Image::Xbm->set( -setch => 'X', -unsetch => ' ' ) ;
           my $s = $p->new_from_string( "XXX", "X X", "XhX" ) ;

       You can also specify a hotspot by making one of the characters a 'H' (set bit hotspot) or
       'h' (unset bit hotspot) -- you can use different characters by setting "-sethotch" and
       "-unsethotch" respectively.

   new_from_serialised()
           my $i = Image::Xbm->new_from_serialised( $s ) ;

       Creates an image from a string created with the "serialse()" method. Since such strings
       are a little more compressed than xbm files or Image::Xbm objects they might be useful if
       storing a lot of bitmaps, or for transferring bitmaps over comms links.

   serialise()
           my $s = $i->serialise ;

       Creates a string version of the image which can be completed recreated using the
       "new_from_serialised" method.

   get()
           my $width = $i->get( -width ) ;
           my( $hotx, $hoty ) = $i->get( -hotx, -hoty ) ;

       Get any of the object's attributes. Multiple attributes may be requested in a single call.

       See "xy" and "vec" to get/set bits of the image itself.

   set()
           $i->set( -hotx => 120, -hoty => 32 ) ;

       Set any of the object's attributes. Multiple attributes may be set in a single call.
       Except for "-setch" and "-unsetch" all attributes are object attributes; some attributes
       are read-only.

       See "xy" and "vec" to get/set bits of the image itself.

   class attributes
           Image::Xbm->set( -setch => 'X' ) ;
           $i->set( -setch => '@', -unsetch => '*' ) ;

       "-setch"
           The character to print set bits as when using "as_string", default is '#'.  This is a
           class attribute accessible from the class or an object via "get" and "set".

       "-unsetch"
           The character to print set bits as when using "as_string", default is '-'.  This is a
           class attribute accessible from the class or an object via "get" and "set".

       "-sethotch"
           The character to print set bits as when using "as_string", default is 'H'.  This is a
           class attribute accessible from the class or an object via "get" and "set".

       "-unsethotch"
           The character to print set bits as when using "as_string", default is 'h'.  This is a
           class attribute accessible from the class or an object via "get" and "set".

   xybit()
           $i->xy( 4, 11, 1 ) ;      # Set the bit at point 4,11
           my $v = $i->xy( 9, 17 ) ; # Get the bit at point 9,17

       Get/set bits using x, y coordinates; coordinates start at 0.

   xy()
           $i->xy( 4, 11, 'black' ) ;  # Set the bit from a colour at point 4,11
           my $v = $i->xy( 9, 17 ) ;   # Get the bit as a colour at point 9,17

       Get/set bits using colours using x, y coordinates; coordinates start at 0.

       If set with a colour of 'black' or a numeric value > 0 or a string not matching /^#0+$/
       then the bit will be set, otherwise it will be cleared.

       If you get a colour you will always get 'black' or 'white'.

   vec()
           $i->vec( 43, 0 ) ;      # Unset the bit at offset 43
           my $v = $i->vec( 87 ) ; # Get the bit at offset 87

       Get/set bits using vector offsets; offsets start at 0.

   load()
           $i->load ;
           $i->load( 'test.xbm' ) ;

       Load the image whose name is given, or if none is given load the image whose name is in
       the "-file" attribute.

   save()
           $i->save ;
           $i->save( 'test.xbm' ) ;

       Save the image using the name given, or if none is given save the image using the name in
       the "-file" attribute. The image is saved in xbm format, e.g.

           #define test_width 6
           #define test_height 6
           static unsigned char test_bits[] = {
            0x1f, 0x07, 0x07, 0x09, 0x11, 0x20 } ;

   is_equal()
           print "equal\n" if $i->is_equal( $j ) ;

       Returns true (1) if the images are equal, false (0) otherwise. Note that hotspots and
       filenames are ignored, so we compare width, height and the actual bits only.

   as_string()
           print $i->as_string ;

       Returns the image as a string, e.g.

           #####-
           ###---
           ###---
           #--#--
           #---#-
           -----#

       The characters used may be changed by "set"ting the "-setch" and "-unsetch" characters. If
       you give "as_string" a parameter it will print out the hotspot if present using
       "-sethotch" or "-unsethotch" as appropriate, e.g.

           print $n->as_string( 1 ) ;

           H##
           #-#
           ###

   as_binstring()
           print $i->as_binstring ;

       Returns the image as a string of 0's and 1's, e.g.

           1111101110001110001001001000100000010000

CHANGES

       2000/11/09

       Added Jerrad Pierce's patch to allow load() to accept filehandles or strings; will
       document in next release.

       2000/05/05

       Added new_from_serialised() and serialise() methods.

       2000/05/04

       Made xy() compatible with Image::Base, use xybit() for the earlier functionality.

       2000/05/01

       Improved speed of vec(), xy() and as_string().

       Tried use integer to improve speed but according to Benchmark it made the code slower so I
       dropped it; interestingly perl 5.6.0 was around 25% slower than perl 5.004 with and
       without use integer.

       2000/04/30

       Created.

AUTHOR

       Mark Summerfield. I can be contacted as <summer@perlpress.com> - please include the word
       'xbm' in the subject line.

COPYRIGHT

       Copyright (c) Mark Summerfield 2000. All Rights Reserved.

       This module may be used/distributed/modified under the LGPL.