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+package GD;
+
+# Copyright 1995 Lincoln D. Stein. See accompanying README file for
+# usage information
+
+use strict;
+require 5.004;
+require FileHandle;
+require Exporter;
+require DynaLoader;
+require AutoLoader;
+use Carp 'croak','carp';
+
+use GD::Image;
+use GD::Polygon;
+
+use vars qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS $AUTOLOAD);
+
+$VERSION = '2.44';
+
+@ISA = qw(Exporter DynaLoader);
+# Items to export into callers namespace by default. Note: do not export
+# names by default without a very good reason. Use EXPORT_OK instead.
+# Do not simply export all your public functions/methods/constants.
+@EXPORT = qw(
+ gdBrushed
+ gdDashSize
+ gdMaxColors
+ gdStyled
+ gdStyledBrushed
+ gdTiled
+ gdTransparent
+ gdAntiAliased
+ gdArc
+ gdChord
+ gdPie
+ gdNoFill
+ gdEdged
+ gdTinyFont
+ gdSmallFont
+ gdMediumBoldFont
+ gdLargeFont
+ gdGiantFont
+ gdAlphaMax
+ gdAlphaOpaque
+ gdAlphaTransparent
+);
+
+@EXPORT_OK = qw (
+ GD_CMP_IMAGE
+ GD_CMP_NUM_COLORS
+ GD_CMP_COLOR
+ GD_CMP_SIZE_X
+ GD_CMP_SIZE_Y
+ GD_CMP_TRANSPARENT
+ GD_CMP_BACKGROUND
+ GD_CMP_INTERLACE
+ GD_CMP_TRUECOLOR
+);
+
+%EXPORT_TAGS = ('cmp' => [qw(GD_CMP_IMAGE
+ GD_CMP_NUM_COLORS
+ GD_CMP_COLOR
+ GD_CMP_SIZE_X
+ GD_CMP_SIZE_Y
+ GD_CMP_TRANSPARENT
+ GD_CMP_BACKGROUND
+ GD_CMP_INTERLACE
+ GD_CMP_TRUECOLOR
+ )
+ ]
+ );
+
+# documentation error
+*GD::Polygon::delete = \&GD::Polygon::deletePt;
+
+sub AUTOLOAD {
+ # This AUTOLOAD is used to 'autoload' constants from the constant()
+ # XS function. If a constant is not found then control is passed
+ # to the AUTOLOAD in AutoLoader.
+
+ my($constname);
+ ($constname = $AUTOLOAD) =~ s/.*:://;
+ my $val = constant($constname);
+ if ($! != 0) {
+ if ($! =~ /Invalid/) {
+ $AutoLoader::AUTOLOAD = $AUTOLOAD;
+ goto &AutoLoader::AUTOLOAD;
+ }
+ else {
+ my($pack,$file,$line) = caller;
+ die "Your vendor has not defined GD macro $pack\:\:$constname, used at $file line $line.\n";
+ }
+ }
+ eval "sub $AUTOLOAD { $val }";
+ goto &$AUTOLOAD;
+}
+
+bootstrap GD;
+
+
+# Preloaded methods go here.
+sub GD::gdSmallFont {
+ return GD::Font->Small;
+}
+
+sub GD::gdLargeFont {
+ return GD::Font->Large;
+}
+
+sub GD::gdMediumBoldFont {
+ return GD::Font->MediumBold;
+}
+
+sub GD::gdTinyFont {
+ return GD::Font->Tiny;
+}
+
+sub GD::gdGiantFont {
+ return GD::Font->Giant;
+}
+
+sub GD::Image::startGroup { } # does nothing - used by GD::SVG
+sub GD::Image::endGroup { } # does nothing - used by GD::SVG
+sub GD::Image::newGroup {
+ my $self = shift;
+ GD::Group->new($self,$self->startGroup);
+}
+
+=head1 NAME
+
+GD.pm - Interface to Gd Graphics Library
+
+=head1 SYNOPSIS
+
+ use GD;
+
+ # create a new image
+ $im = new GD::Image(100,100);
+
+ # allocate some colors
+ $white = $im->colorAllocate(255,255,255);
+ $black = $im->colorAllocate(0,0,0);
+ $red = $im->colorAllocate(255,0,0);
+ $blue = $im->colorAllocate(0,0,255);
+
+ # make the background transparent and interlaced
+ $im->transparent($white);
+ $im->interlaced('true');
+
+ # Put a black frame around the picture
+ $im->rectangle(0,0,99,99,$black);
+
+ # Draw a blue oval
+ $im->arc(50,50,95,75,0,360,$blue);
+
+ # And fill it with red
+ $im->fill(50,50,$red);
+
+ # make sure we are writing to a binary stream
+ binmode STDOUT;
+
+ # Convert the image to PNG and print it on standard output
+ print $im->png;
+
+=head1 DESCRIPTION
+
+B<GD.pm> is a Perl interface to Thomas Boutell's gd graphics library
+(version 2.01 or higher; see below). GD allows you to create color
+drawings using a large number of graphics primitives, and emit the
+drawings as PNG files.
+
+GD defines the following four classes:
+
+=over 5
+
+
+=item C<GD::Image>
+
+An image class, which holds the image data and accepts graphic
+primitive method calls.
+
+=item C<GD::Font>
+
+A font class, which holds static font information and used for text
+rendering.
+
+=item C<GD::Polygon>
+
+A simple polygon object, used for storing lists of vertices prior to
+rendering a polygon into an image.
+
+=item C<GD::Simple>
+
+A "simple" class that simplifies the GD::Image API and then adds a set
+of object-oriented drawing methods using turtle graphics, simplified
+font handling, ability to work in polar coordinates, HSV color spaces,
+and human-readable color names like "lightblue". Please see
+L<GD::Simple> for a description of these methods.
+
+=back
+
+A Simple Example:
+
+ #!/usr/local/bin/perl
+
+ use GD;
+
+ # create a new image
+ $im = new GD::Image(100,100);
+
+ # allocate some colors
+ $white = $im->colorAllocate(255,255,255);
+ $black = $im->colorAllocate(0,0,0);
+ $red = $im->colorAllocate(255,0,0);
+ $blue = $im->colorAllocate(0,0,255);
+
+ # make the background transparent and interlaced
+ $im->transparent($white);
+ $im->interlaced('true');
+
+ # Put a black frame around the picture
+ $im->rectangle(0,0,99,99,$black);
+
+ # Draw a blue oval
+ $im->arc(50,50,95,75,0,360,$blue);
+
+ # And fill it with red
+ $im->fill(50,50,$red);
+
+ # make sure we are writing to a binary stream
+ binmode STDOUT;
+
+ # Convert the image to PNG and print it on standard output
+ print $im->png;
+
+Notes:
+
+=over 5
+
+=item 1.
+To create a new, empty image, send a new() message to GD::Image, passing
+it the width and height of the image you want to create. An image
+object will be returned. Other class methods allow you to initialize
+an image from a preexisting JPG, PNG, GD, GD2 or XBM file.
+
+=item 2.
+Next you will ordinarily add colors to the image's color table.
+colors are added using a colorAllocate() method call. The three
+parameters in each call are the red, green and blue (rgb) triples for
+the desired color. The method returns the index of that color in the
+image's color table. You should store these indexes for later use.
+
+=item 3.
+Now you can do some drawing! The various graphics primitives are
+described below. In this example, we do some text drawing, create an
+oval, and create and draw a polygon.
+
+=item 4.
+Polygons are created with a new() message to GD::Polygon. You can add
+points to the returned polygon one at a time using the addPt() method.
+The polygon can then be passed to an image for rendering.
+
+=item 5.
+When you're done drawing, you can convert the image into PNG format by
+sending it a png() message. It will return a (potentially large)
+scalar value containing the binary data for the image. Ordinarily you
+will print it out at this point or write it to a file. To ensure
+portability to platforms that differentiate between text and binary
+files, be sure to call C<binmode()> on the file you are writing
+the image to.
+
+=back
+
+=head1 Object Constructors: Creating Images
+
+The following class methods allow you to create new GD::Image objects.
+
+=over 4
+
+=item B<$image = GD::Image-E<gt>new([$width,$height],[$truecolor])>
+
+=item B<$image = GD::Image-E<gt>new(*FILEHANDLE)>
+
+=item B<$image = GD::Image-E<gt>new($filename)>
+
+=item B<$image = GD::Image-E<gt>new($data)>
+
+The new() method is the main constructor for the GD::Image class.
+Called with two integer arguments, it creates a new blank image of the
+specified width and height. For example:
+
+ $myImage = new GD::Image(100,100) || die;
+
+This will create an image that is 100 x 100 pixels wide. If you don't
+specify the dimensions, a default of 64 x 64 will be chosen.
+
+The optional third argument, $truecolor, tells new() to create a
+truecolor GD::Image object. Truecolor images have 24 bits of color
+data (eight bits each in the red, green and blue channels
+respectively), allowing for precise photograph-quality color usage.
+If not specified, the image will use an 8-bit palette for
+compatibility with older versions of libgd.
+
+Alternatively, you may create a GD::Image object based on an existing
+image by providing an open filehandle, a filename, or the image data
+itself. The image formats automatically recognized and accepted are:
+PNG, JPEG, XPM and GD2. Other formats, including WBMP, and GD
+version 1, cannot be recognized automatically at this time.
+
+If something goes wrong (e.g. insufficient memory), this call will
+return undef.
+
+=item B<$image = GD::Image-E<gt>trueColor([0,1])>
+
+For backwards compatibility with scripts previous versions of GD,
+new images created from scratch (width, height) are palette based
+by default. To change this default to create true color images use:
+
+ GD::Image->trueColor(1);
+
+somewhere before creating new images. To switch back to palette
+based by default, use:
+
+ GD::Image->trueColor(0);
+
+=item B<$image = GD::Image-E<gt>newPalette([$width,$height])>
+
+=item B<$image = GD::Image-E<gt>newTrueColor([$width,$height])>
+
+The newPalette() and newTrueColor() methods can be used to explicitly
+create an palette based or true color image regardless of the
+current setting of trueColor().
+
+=item B<$image = GD::Image-E<gt>newFromPng($file, [$truecolor])>
+
+=item B<$image = GD::Image-E<gt>newFromPngData($data, [$truecolor])>
+
+The newFromPng() method will create an image from a PNG file read in
+through the provided filehandle or file path. The filehandle must
+previously have been opened on a valid PNG file or pipe. If
+successful, this call will return an initialized image which you can
+then manipulate as you please. If it fails, which usually happens if
+the thing at the other end of the filehandle is not a valid PNG file,
+the call returns undef. Notice that the call doesn't automatically
+close the filehandle for you. But it does call C<binmode(FILEHANDLE)>
+for you, on platforms where this matters.
+
+You may use any of the following as the argument:
+
+ 1) a simple filehandle, such as STDIN
+ 2) a filehandle glob, such as *PNG
+ 3) a reference to a glob, such as \*PNG
+ 4) an IO::Handle object
+ 5) the pathname of a file
+
+In the latter case, newFromPng() will attempt to open the file for you
+and read the PNG information from it.
+
+ Example1:
+
+ open (PNG,"barnswallow.png") || die;
+ $myImage = newFromPng GD::Image(\*PNG) || die;
+ close PNG;
+
+ Example2:
+ $myImage = newFromPng GD::Image('barnswallow.png');
+
+To get information about the size and color usage of the information,
+you can call the image query methods described below. Images created
+by reading PNG images will be truecolor if the image file itself is
+truecolor. To force the image to be palette-based, pass a value of 0
+in the optional $truecolor argument.
+
+The newFromPngData() method will create a new GD::Image initialized
+with the PNG format B<data> contained in C<$data>.
+
+=item B<$image = GD::Image-E<gt>newFromJpeg($file, [$truecolor])>
+
+=item B<$image = GD::Image-E<gt>newFromJpegData($data, [$truecolor])>
+
+These methods will create an image from a JPEG file. They work just
+like newFromPng() and newFromPngData(), and will accept the same
+filehandle and pathname arguments.
+
+Images created by reading JPEG images will always be truecolor. To
+force the image to be palette-based, pass a value of 0 in the optional
+$truecolor argument.
+
+=item B<$image = GD::Image-E<gt>newFromGif($file)>
+
+=item B<$image = GD::Image-E<gt>newFromGifData($data)>
+
+These methods will create an image from a GIF file. They work just
+like newFromPng() and newFromPngData(), and will accept the same
+filehandle and pathname arguments.
+
+Images created from GIFs are always 8-bit palette images. To convert
+to truecolor, you must create a truecolor image and then perform a
+copy.
+
+=item B<$image = GD::Image-E<gt>newFromXbm($file)>
+
+This works in exactly the same way as C<newFromPng>, but reads the
+contents of an X Bitmap (black & white) file:
+
+ open (XBM,"coredump.xbm") || die;
+ $myImage = newFromXbm GD::Image(\*XBM) || die;
+ close XBM;
+
+There is no newFromXbmData() function, because there is no
+corresponding function in the gd library.
+
+=item B<$image = GD::Image-E<gt>newFromGd($file)>
+
+=item B<$image = GD::Image-E<gt>newFromGdData($data)>
+
+These methods initialize a GD::Image from a Gd file, filehandle, or
+data. Gd is Tom Boutell's disk-based storage format, intended for the
+rare case when you need to read and write the image to disk quickly.
+It's not intended for regular use, because, unlike PNG or JPEG, no
+image compression is performed and these files can become B<BIG>.
+
+ $myImage = newFromGd GD::Image("godzilla.gd") || die;
+ close GDF;
+
+=item B<$image = GD::Image-E<gt>newFromGd2($file)>
+
+=item B<$image = GD::Image-E<gt>newFromGd2Data($data)>
+
+This works in exactly the same way as C<newFromGd()> and
+newFromGdData, but use the new compressed GD2 image format.
+
+=item B<$image = GD::Image-E<gt>newFromGd2Part($file,srcX,srcY,width,height)>
+
+This class method allows you to read in just a portion of a GD2 image
+file. In addition to a filehandle, it accepts the top-left corner and
+dimensions (width,height) of the region of the image to read. For
+example:
+
+ open (GDF,"godzilla.gd2") || die;
+ $myImage = GD::Image->newFromGd2Part(\*GDF,10,20,100,100) || die;
+ close GDF;
+
+This reads a 100x100 square portion of the image starting from
+position (10,20).
+
+=item B<$image = GD::Image-E<gt>newFromXpm($filename)>
+
+This creates a new GD::Image object starting from a B<filename>. This
+is unlike the other newFrom() functions because it does not take a
+filehandle. This difference comes from an inconsistency in the
+underlying gd library.
+
+ $myImage = newFromXpm GD::Image('earth.xpm') || die;
+
+This function is only available if libgd was compiled with XPM
+support.
+
+NOTE: The libgd library is unable to read certain XPM files, returning
+an all-black image instead.
+
+=head1 GD::Image Methods
+
+Once a GD::Image object is created, you can draw with it, copy it, and
+merge two images. When you are finished manipulating the object, you
+can convert it into a standard image file format to output or save to
+a file.
+
+=head2 Image Data Output Methods
+
+The following methods convert the internal drawing format into
+standard output file formats.
+
+=item B<$pngdata = $image-E<gt>png([$compression_level])>
+
+This returns the image data in PNG format. You can then print it,
+pipe it to a display program, or write it to a file. Example:
+
+ $png_data = $myImage->png;
+ open (DISPLAY,"| display -") || die;
+ binmode DISPLAY;
+ print DISPLAY $png_data;
+ close DISPLAY;
+
+Note the use of C<binmode()>. This is crucial for portability to
+DOSish platforms.
+
+The optional $compression_level argument controls the amount of
+compression to apply to the output PNG image. Values range from 0-9,
+where 0 means no compression (largest files, highest quality) and 9
+means maximum compression (smallest files, worst quality). A
+compression level of -1 uses the default compression level selected
+when zlib was compiled on your system, and is the same as calling
+png() with no argument. Be careful not to confuse this argument with
+the jpeg() quality argument, which ranges from 0-100 and has the
+opposite meaning from compression (higher numbers give higher
+quality).
+
+=item B<$gifdata = $image-E<gt>gifanimbegin([$GlobalCM [, $Loops]])>
+
+For libgd version 2.0.33 and higher, this call begins an animated GIF
+by returning the data that comprises animated gif image file header.
+After you call this method, call gifanimadd() one or more times to add
+the frames of the image. Then call gifanimend(). Each frame must be
+the same width and height.
+
+A typical sequence will look like this:
+
+ my $gifdata = $image->gifanimbegin;
+ $gifdata .= $image->gifanimadd; # first frame
+ for (1..100) {
+ # make a frame of right size
+ my $frame = GD::Image->new($image->getBounds);
+ add_frame_data($frame); # add the data for this frame
+ $gifdata .= $frame->gifanimadd; # add frame
+ }
+ $gifdata .= $image->gifanimend; # finish the animated GIF
+ print $gifdata; # write animated gif to STDOUT
+
+If you do not wish to store the data in memory, you can print it to
+stdout or a file.
+
+The image that you call gifanimbegin on is used to set the image size,
+color resolution and color map. If argument $GlobalCM is 1, the image
+color map becomes the GIF89a global color map. If $Loops is given and
+>= 0, the NETSCAPE2.0 application extension is created, with looping
+count. Looping count 0 means forever.
+
+=item B<$gifdata = $image-E<gt>gifanimadd([$LocalCM [, $LeftOfs [, $TopOfs [, $Delay [, $Disposal [, $previm]]]]]])>
+
+Returns the data that comprises one animated gif image frame. You can
+then print it, pipe it to a display program, or write it to a file.
+With $LeftOfs and $TopOfs you can place this frame in different offset
+than (0,0) inside the image screen. Delay between the previous frame
+and this frame is in 1/100s units. Disposal is usually and by default
+1. Compression is activated by giving the previous image as a
+parameter. This function then compares the images and only writes the
+changed pixels to the new frame in animation. The Disposal parameter
+for optimized animations must be set to 1, also for the first frame.
+$LeftOfs and $TopOfs parameters are ignored for optimized frames.
+
+=item B<$gifdata = $image-E<gt>gifanimend()>
+
+Returns the data for end segment of animated gif file. It always
+returns string ';'. This string must be printed to an animated gif
+file after all image frames to properly terminate it according to GIF
+file syntax. Image object is not used at all in this method.
+
+=item B<$jpegdata = $image-E<gt>jpeg([$quality])>
+
+This returns the image data in JPEG format. You can then print it,
+pipe it to a display program, or write it to a file. You may pass an
+optional quality score to jpeg() in order to control the JPEG quality.
+This should be an integer between 0 and 100. Higher quality scores
+give larger files and better image quality. If you don't specify the
+quality, jpeg() will choose a good default.
+
+=item B<$gifdata = $image-E<gt>gif()>.
+
+This returns the image data in GIF format. You can then print it,
+pipe it to a display program, or write it to a file.
+
+=item B<$gddata = $image-E<gt>gd>
+
+This returns the image data in GD format. You can then print it,
+pipe it to a display program, or write it to a file. Example:
+
+ binmode MYOUTFILE;
+ print MYOUTFILE $myImage->gd;
+
+=item B<$gd2data = $image-E<gt>gd2>
+
+Same as gd(), except that it returns the data in compressed GD2
+format.
+
+=item B<$wbmpdata = $image-E<gt>wbmp([$foreground])>
+
+This returns the image data in WBMP format, which is a black-and-white
+image format. Provide the index of the color to become the foreground
+color. All other pixels will be considered background.
+
+=back
+
+=head2 Color Control
+
+These methods allow you to control and manipulate the GD::Image color
+table.
+
+=over 4
+
+=item B<$index = $image-E<gt>colorAllocate(red,green,blue)>
+
+This allocates a color with the specified red, green and blue
+components and returns its index in the color table, if specified.
+The first color allocated in this way becomes the image's background
+color. (255,255,255) is white (all pixels on). (0,0,0) is black (all
+pixels off). (255,0,0) is fully saturated red. (127,127,127) is 50%
+gray. You can find plenty of examples in /usr/X11/lib/X11/rgb.txt.
+
+If no colors are allocated, then this function returns -1.
+
+Example:
+
+ $white = $myImage->colorAllocate(0,0,0); #background color
+ $black = $myImage->colorAllocate(255,255,255);
+ $peachpuff = $myImage->colorAllocate(255,218,185);
+
+=item B<$index = $image-E<gt>colorAllocateAlpha(reg,green,blue,alpha)>
+
+This allocates a color with the specified red, green, and blue components,
+plus the specified alpha channel. The alpha value may range from 0 (opaque)
+to 127 (transparent). The C<alphaBlending> function changes the way this
+alpha channel affects the resulting image.
+
+=item B<$image-E<gt>colorDeallocate(colorIndex)>
+
+This marks the color at the specified index as being ripe for
+reallocation. The next time colorAllocate is used, this entry will be
+replaced. You can call this method several times to deallocate
+multiple colors. There's no function result from this call.
+
+Example:
+
+ $myImage->colorDeallocate($peachpuff);
+ $peachy = $myImage->colorAllocate(255,210,185);
+
+=item B<$index = $image-E<gt>colorClosest(red,green,blue)>
+
+This returns the index of the color closest in the color table to the
+red green and blue components specified. If no colors have yet been
+allocated, then this call returns -1.
+
+Example:
+
+ $apricot = $myImage->colorClosest(255,200,180);
+
+=item B<$index = $image-E<gt>colorClosestHWB(red,green,blue)>
+
+This also attempts to return the color closest in the color table to the
+red green and blue components specified. It uses a Hue/White/Black
+color representation to make the selected color more likely to match
+human perceptions of similar colors.
+
+If no colors have yet been
+allocated, then this call returns -1.
+
+Example:
+
+ $mostred = $myImage->colorClosestHWB(255,0,0);
+
+=item B<$index = $image-E<gt>colorExact(red,green,blue)>
+
+This returns the index of a color that exactly matches the specified
+red green and blue components. If such a color is not in the color
+table, this call returns -1.
+
+ $rosey = $myImage->colorExact(255,100,80);
+ warn "Everything's coming up roses.\n" if $rosey >= 0;
+
+=item B<$index = $image-E<gt>colorResolve(red,green,blue)>
+
+This returns the index of a color that exactly matches the specified
+red green and blue components. If such a color is not in the color
+table and there is room, then this method allocates the color in the
+color table and returns its index.
+
+ $rosey = $myImage->colorResolve(255,100,80);
+ warn "Everything's coming up roses.\n" if $rosey >= 0;
+
+=item B<$colorsTotal = $image-E<gt>colorsTotal> I<object method>
+
+This returns the total number of colors allocated in the object.
+
+ $maxColors = $myImage->colorsTotal;
+
+In the case of a TrueColor image, this call will return undef.
+
+=item B<$index = $image-E<gt>getPixel(x,y)> I<object method>
+
+This returns the color table index underneath the specified
+point. It can be combined with rgb()
+to obtain the rgb color underneath the pixel.
+
+Example:
+
+ $index = $myImage->getPixel(20,100);
+ ($r,$g,$b) = $myImage->rgb($index);
+
+=item B<($red,$green,$blue) = $image-E<gt>rgb($index)>
+
+This returns a list containing the red, green and blue components of
+the specified color index.
+
+Example:
+
+ @RGB = $myImage->rgb($peachy);
+
+=item B<$image-E<gt>transparent($colorIndex)>
+
+This marks the color at the specified index as being transparent.
+Portions of the image drawn in this color will be invisible. This is
+useful for creating paintbrushes of odd shapes, as well as for
+making PNG backgrounds transparent for displaying on the Web. Only
+one color can be transparent at any time. To disable transparency,
+specify -1 for the index.
+
+If you call this method without any parameters, it will return the
+current index of the transparent color, or -1 if none.
+
+Example:
+
+ open(PNG,"test.png");
+ $im = newFromPng GD::Image(PNG);
+ $white = $im->colorClosest(255,255,255); # find white
+ $im->transparent($white);
+ binmode STDOUT;
+ print $im->png;
+
+=back
+
+=head2 Special Colors
+
+GD implements a number of special colors that can be used to achieve
+special effects. They are constants defined in the GD::
+namespace, but automatically exported into your namespace when the GD
+module is loaded.
+
+=over 4
+
+=item B<$image-E<gt>setBrush($image)>
+
+You can draw lines and shapes using a brush pattern. Brushes are just
+images that you can create and manipulate in the usual way. When you
+draw with them, their contents are used for the color and shape of the
+lines.
+
+To make a brushed line, you must create or load the brush first, then
+assign it to the image using setBrush(). You can then draw in that
+with that brush using the B<gdBrushed> special color. It's often
+useful to set the background of the brush to transparent so that the
+non-colored parts don't overwrite other parts of your image.
+
+Example:
+
+ # Create a brush at an angle
+ $diagonal_brush = new GD::Image(5,5);
+ $white = $diagonal_brush->colorAllocate(255,255,255);
+ $black = $diagonal_brush->colorAllocate(0,0,0);
+ $diagonal_brush->transparent($white);
+ $diagonal_brush->line(0,4,4,0,$black); # NE diagonal
+
+ # Set the brush
+ $myImage->setBrush($diagonal_brush);
+
+ # Draw a circle using the brush
+ $myImage->arc(50,50,25,25,0,360,gdBrushed);
+
+=item B<$image-E<gt>setThickness($thickness)>
+
+Lines drawn with line(), rectangle(), arc(), and so forth are 1 pixel
+thick by default. Call setThickness() to change the line drawing
+width.
+
+=item B<$image-E<gt>setStyle(@colors)>
+
+Styled lines consist of an arbitrary series of repeated colors and are
+useful for generating dotted and dashed lines. To create a styled
+line, use setStyle() to specify a repeating series of colors. It
+accepts an array consisting of one or more color indexes. Then draw
+using the B<gdStyled> special color. Another special color,
+B<gdTransparent> can be used to introduce holes in the line, as the
+example shows.
+
+Example:
+
+ # Set a style consisting of 4 pixels of yellow,
+ # 4 pixels of blue, and a 2 pixel gap
+ $myImage->setStyle($yellow,$yellow,$yellow,$yellow,
+ $blue,$blue,$blue,$blue,
+ gdTransparent,gdTransparent);
+ $myImage->arc(50,50,25,25,0,360,gdStyled);
+
+To combine the C<gdStyled> and C<gdBrushed> behaviors, you can specify
+C<gdStyledBrushed>. In this case, a pixel from the current brush
+pattern is rendered wherever the color specified in setStyle() is
+neither gdTransparent nor 0.
+
+=item B<gdTiled>
+
+Draw filled shapes and flood fills using a pattern. The pattern is
+just another image. The image will be tiled multiple times in order
+to fill the required space, creating wallpaper effects. You must call
+C<setTile> in order to define the particular tile pattern you'll use
+for drawing when you specify the gdTiled color.
+details.
+
+=item B<gdStyled>
+
+The gdStyled color is used for creating dashed and dotted lines. A
+styled line can contain any series of colors and is created using the
+setStyled() command.
+
+=item B<gdAntiAliased>
+
+The C<gdAntiAliased> color is used for drawing lines with antialiasing
+turned on. Antialiasing will blend the jagged edges of lines with the
+background, creating a smoother look. The actual color drawn is set
+with setAntiAliased().
+
+=item B<$image-E<gt>setAntiAliased($color)>
+
+"Antialiasing" is a process by which jagged edges associated with line
+drawing can be reduced by blending the foreground color with an
+appropriate percentage of the background, depending on how much of the
+pixel in question is actually within the boundaries of the line being
+drawn. All line-drawing methods, such as line() and polygon, will draw
+antialiased lines if the special "color" B<gdAntiAliased> is used when
+calling them.
+
+setAntiAliased() is used to specify the actual foreground color to be
+used when drawing antialiased lines. You may set any color to be the
+foreground, however as of libgd version 2.0.12 an alpha channel
+component is not supported.
+
+Antialiased lines can be drawn on both truecolor and palette-based
+images. However, attempts to draw antialiased lines on highly complex
+palette-based backgrounds may not give satisfactory results, due to
+the limited number of colors available in the palette. Antialiased
+line-drawing on simple backgrounds should work well with palette-based
+images; otherwise create or fetch a truecolor image instead. When
+using palette-based images, be sure to allocate a broad spectrum of
+colors in order to have sufficient colors for the antialiasing to use.
+
+=item B<$image-E<gt>setAntiAliasedDontBlend($color,[$flag])>
+
+Normally, when drawing lines with the special B<gdAntiAliased>
+"color," blending with the background to reduce jagged edges is the
+desired behavior. However, when it is desired that lines not be
+blended with one particular color when it is encountered in the
+background, the setAntiAliasedDontBlend() method can be used to
+indicate the special color that the foreground should stand out more
+clearly against.
+
+Once turned on, you can turn this feature off by calling
+setAntiAliasedDontBlend() with a second argument of 0:
+
+ $image->setAntiAliasedDontBlend($color,0);
+
+=back
+
+=head2 Drawing Commands
+
+These methods allow you to draw lines, rectangles, and ellipses, as
+well as to perform various special operations like flood-fill.
+
+=over 4
+
+=item B<$image-E<gt>setPixel($x,$y,$color)>
+
+This sets the pixel at (x,y) to the specified color index. No value
+is returned from this method. The coordinate system starts at the
+upper left at (0,0) and gets larger as you go down and to the right.
+You can use a real color, or one of the special colors gdBrushed,
+gdStyled and gdStyledBrushed can be specified.
+
+Example:
+
+ # This assumes $peach already allocated
+ $myImage->setPixel(50,50,$peach);
+
+=item B<$image-E<gt>line($x1,$y1,$x2,$y2,$color)>
+
+This draws a line from (x1,y1) to (x2,y2) of the specified color. You
+can use a real color, or one of the special colors gdBrushed,
+gdStyled and gdStyledBrushed.
+
+Example:
+
+ # Draw a diagonal line using the currently defined
+ # paintbrush pattern.
+ $myImage->line(0,0,150,150,gdBrushed);
+
+=item B<$image-E<gt>dashedLine($x1,$y1,$x2,$y2,$color)>
+
+DEPRECATED: The libgd library provides this method solely for backward
+compatibility with libgd version 1.0, and there have been reports that
+it no longer works as expected. Please use the setStyle() and gdStyled
+methods as described below.
+
+This draws a dashed line from (x1,y1) to (x2,y2) in the specified
+color. A more powerful way to generate arbitrary dashed and dotted
+lines is to use the setStyle() method described below and to draw with
+the special color gdStyled.
+
+Example:
+
+ $myImage->dashedLine(0,0,150,150,$blue);
+
+=item B<$image-E<gt>rectangle($x1,$y1,$x2,$y2,$color)>
+
+This draws a rectangle with the specified color. (x1,y1) and (x2,y2)
+are the upper left and lower right corners respectively. Both real
+color indexes and the special colors gdBrushed, gdStyled and
+gdStyledBrushed are accepted.
+
+Example:
+
+ $myImage->rectangle(10,10,100,100,$rose);
+
+=item B<$image-E<gt>filledRectangle($x1,$y1,$x2,$y2,$color)>
+
+This draws a rectangle filed with the specified color. You can use a
+real color, or the special fill color gdTiled to fill the polygon
+with a pattern.
+
+Example:
+
+ # read in a fill pattern and set it
+ $tile = newFromPng GD::Image('happyface.png');
+ $myImage->setTile($tile);
+
+ # draw the rectangle, filling it with the pattern
+ $myImage->filledRectangle(10,10,150,200,gdTiled);
+
+=item B<$image-E<gt>openPolygon($polygon,$color)>
+
+This draws a polygon with the specified color. The polygon must be
+created first (see below). The polygon must have at least three
+vertices. If the last vertex doesn't close the polygon, the method
+will close it for you. Both real color indexes and the special
+colors gdBrushed, gdStyled and gdStyledBrushed can be specified.
+
+Example:
+
+ $poly = new GD::Polygon;
+ $poly->addPt(50,0);
+ $poly->addPt(99,99);
+ $poly->addPt(0,99);
+ $myImage->openPolygon($poly,$blue);
+
+=item B<$image-E<gt>unclosedPolygon($polygon,$color)>
+
+This draws a sequence of connected lines with the specified color,
+without connecting the first and last point to a closed polygon. The
+polygon must be created first (see below). The polygon must have at
+least three vertices. Both real color indexes and the special colors
+gdBrushed, gdStyled and gdStyledBrushed can be specified.
+
+You need libgd 2.0.33 or higher to use this feature.
+
+Example:
+
+ $poly = new GD::Polygon;
+ $poly->addPt(50,0);
+ $poly->addPt(99,99);
+ $poly->addPt(0,99);
+ $myImage->unclosedPolygon($poly,$blue);
+
+=item B<$image-E<gt>filledPolygon($poly,$color)>
+
+This draws a polygon filled with the specified color. You can use a
+real color, or the special fill color gdTiled to fill the polygon
+with a pattern.
+
+Example:
+
+ # make a polygon
+ $poly = new GD::Polygon;
+ $poly->addPt(50,0);
+ $poly->addPt(99,99);
+ $poly->addPt(0,99);
+
+ # draw the polygon, filling it with a color
+ $myImage->filledPolygon($poly,$peachpuff);
+
+=item B<$image-E<gt>ellipse($cx,$cy,$width,$height,$color)>
+
+=item B<$image-E<gt>filledEllipse($cx,$cy,$width,$height,$color)>
+
+These methods() draw ellipses. ($cx,$cy) is the center of the arc, and
+($width,$height) specify the ellipse width and height, respectively.
+filledEllipse() is like Ellipse() except that the former produces
+filled versions of the ellipse.
+
+=item B<$image-E<gt>arc($cx,$cy,$width,$height,$start,$end,$color)>
+
+This draws arcs and ellipses. (cx,cy) are the center of the arc, and
+(width,height) specify the width and height, respectively. The
+portion of the ellipse covered by the arc are controlled by start and
+end, both of which are given in degrees from 0 to 360. Zero is at the
+top of the ellipse, and angles increase clockwise. To specify a
+complete ellipse, use 0 and 360 as the starting and ending angles. To
+draw a circle, use the same value for width and height.
+
+You can specify a normal color or one of the special colors
+B<gdBrushed>, B<gdStyled>, or B<gdStyledBrushed>.
+
+Example:
+
+ # draw a semicircle centered at 100,100
+ $myImage->arc(100,100,50,50,0,180,$blue);
+
+=item B<$image-E<gt>filledArc($cx,$cy,$width,$height,$start,$end,$color [,$arc_style])>
+
+This method is like arc() except that it colors in the pie wedge with
+the selected color. $arc_style is optional. If present it is a
+bitwise OR of the following constants:
+
+ gdArc connect start & end points of arc with a rounded edge
+ gdChord connect start & end points of arc with a straight line
+ gdPie synonym for gdChord
+ gdNoFill outline the arc or chord
+ gdEdged connect beginning and ending of the arc to the center
+
+gdArc and gdChord are mutually exclusive. gdChord just connects the
+starting and ending angles with a straight line, while gdArc produces
+a rounded edge. gdPie is a synonym for gdArc. gdNoFill indicates that
+the arc or chord should be outlined, not filled. gdEdged, used
+together with gdNoFill, indicates that the beginning and ending angles
+should be connected to the center; this is a good way to outline
+(rather than fill) a "pie slice."
+
+Example:
+
+ $image->filledArc(100,100,50,50,0,90,$blue,gdEdged|gdNoFill);
+
+=item B<$image-E<gt>fill($x,$y,$color)>
+
+This method flood-fills regions with the specified color. The color
+will spread through the image, starting at point (x,y), until it is
+stopped by a pixel of a different color from the starting pixel (this
+is similar to the "paintbucket" in many popular drawing toys). You
+can specify a normal color, or the special color gdTiled, to flood-fill
+with patterns.
+
+Example:
+
+ # Draw a rectangle, and then make its interior blue
+ $myImage->rectangle(10,10,100,100,$black);
+ $myImage->fill(50,50,$blue);
+
+=item B<$image-E<gt>fillToBorder($x,$y,$bordercolor,$color)>
+
+Like C<fill>, this method flood-fills regions with the specified
+color, starting at position (x,y). However, instead of stopping when
+it hits a pixel of a different color than the starting pixel, flooding
+will only stop when it hits the color specified by bordercolor. You
+must specify a normal indexed color for the bordercolor. However, you
+are free to use the gdTiled color for the fill.
+
+Example:
+
+ # This has the same effect as the previous example
+ $myImage->rectangle(10,10,100,100,$black);
+ $myImage->fillToBorder(50,50,$black,$blue);
+
+=back
+
+
+
+=head2 Image Copying Commands
+
+Two methods are provided for copying a rectangular region from one
+image to another. One method copies a region without resizing it.
+The other allows you to stretch the region during the copy operation.
+
+With either of these methods it is important to know that the routines
+will attempt to flesh out the destination image's color table to match
+the colors that are being copied from the source. If the
+destination's color table is already full, then the routines will
+attempt to find the best match, with varying results.
+
+=over 4
+
+=item B<$image-E<gt>copy($sourceImage,$dstX,$dstY,>
+
+B< $srcX,$srcY,$width,$height)>
+
+This is the simplest of the several copy operations, copying the
+specified region from the source image to the destination image (the
+one performing the method call). (srcX,srcY) specify the upper left
+corner of a rectangle in the source image, and (width,height) give the
+width and height of the region to copy. (dstX,dstY) control where in
+the destination image to stamp the copy. You can use the same image
+for both the source and the destination, but the source and
+destination regions must not overlap or strange things will happen.
+
+Example:
+
+ $myImage = new GD::Image(100,100);
+ ... various drawing stuff ...
+ $srcImage = new GD::Image(50,50);
+ ... more drawing stuff ...
+ # copy a 25x25 pixel region from $srcImage to
+ # the rectangle starting at (10,10) in $myImage
+ $myImage->copy($srcImage,10,10,0,0,25,25);
+
+=item B<$image-E<gt>clone()>
+
+Make a copy of the image and return it as a new object. The new image
+will look identical. However, it may differ in the size of the color
+palette and other nonessential details.
+
+Example:
+
+ $myImage = new GD::Image(100,100);
+ ... various drawing stuff ...
+ $copy = $myImage->clone;
+
+=item B<$image-E<gt>copyMerge($sourceImage,$dstX,$dstY,>
+
+B< $srcX,$srcY,$width,$height,$percent)>
+
+This copies the indicated rectangle from the source image to the
+destination image, merging the colors to the extent specified by
+percent (an integer between 0 and 100). Specifying 100% has the same
+effect as copy() -- replacing the destination pixels with the source
+image. This is most useful for highlighting an area by merging in a
+solid rectangle.
+
+Example:
+
+ $myImage = new GD::Image(100,100);
+ ... various drawing stuff ...
+ $redImage = new GD::Image(50,50);
+ ... more drawing stuff ...
+ # copy a 25x25 pixel region from $srcImage to
+ # the rectangle starting at (10,10) in $myImage, merging 50%
+ $myImage->copyMerge($srcImage,10,10,0,0,25,25,50);
+
+=item B<$image-E<gt>copyMergeGray($sourceImage,$dstX,$dstY,>
+
+B< $srcX,$srcY,$width,$height,$percent)>
+
+This is identical to copyMerge() except that it preserves the hue of
+the source by converting all the pixels of the destination rectangle
+to grayscale before merging.
+
+=item B<$image-E<gt>copyResized($sourceImage,$dstX,$dstY,>
+
+B< $srcX,$srcY,$destW,$destH,$srcW,$srcH)>
+
+This method is similar to copy() but allows you to choose different
+sizes for the source and destination rectangles. The source and
+destination rectangle's are specified independently by (srcW,srcH) and
+(destW,destH) respectively. copyResized() will stretch or shrink the
+image to accommodate the size requirements.
+
+Example:
+
+ $myImage = new GD::Image(100,100);
+ ... various drawing stuff ...
+ $srcImage = new GD::Image(50,50);
+ ... more drawing stuff ...
+ # copy a 25x25 pixel region from $srcImage to
+ # a larger rectangle starting at (10,10) in $myImage
+ $myImage->copyResized($srcImage,10,10,0,0,50,50,25,25);
+
+=item B<$image-E<gt>copyResampled($sourceImage,$dstX,$dstY,>
+
+B< $srcX,$srcY,$destW,$destH,$srcW,$srcH)>
+
+This method is similar to copyResized() but provides "smooth" copying
+from a large image to a smaller one, using a weighted average of the
+pixels of the source area rather than selecting one representative
+pixel. This method is identical to copyResized() when the destination
+image is a palette image.
+
+=item B<$image-E<gt>copyRotated($sourceImage,$dstX,$dstY,>
+
+B< $srcX,$srcY,$width,$height,$angle)>
+
+Like copyResized() but the $angle argument specifies an arbitrary
+amount to rotate the image clockwise (in degrees). In addition, $dstX
+and $dstY species the B<center> of the destination image, and not the
+top left corner.
+
+=item B<$image-E<gt>trueColorToPalette([$dither], [$colors])>
+
+This method converts a truecolor image to a palette image. The code for
+this function was originally drawn from the Independent JPEG Group library
+code, which is excellent. The code has been modified to preserve as much
+alpha channel information as possible in the resulting palette, in addition
+to preserving colors as well as possible. This does not work as well as
+might be hoped. It is usually best to simply produce a truecolor
+output image instead, which guarantees the highest output quality.
+Both the dithering (0/1, default=0) and maximum number of colors used
+(<=256, default = gdMaxColors) can be specified.
+
+=back
+
+=head2 Image Transformation Commands
+
+Gd also provides some common image transformations:
+
+=over 4
+
+=item B<$image = $sourceImage-E<gt>copyRotate90()>
+
+=item B<$image = $sourceImage-E<gt>copyRotate180()>
+
+=item B<$image = $sourceImage-E<gt>copyRotate270()>
+
+=item B<$image = $sourceImage-E<gt>copyFlipHorizontal()>
+
+=item B<$image = $sourceImage-E<gt>copyFlipVertical()>
+
+=item B<$image = $sourceImage-E<gt>copyTranspose()>
+
+=item B<$image = $sourceImage-E<gt>copyReverseTranspose()>
+
+These methods can be used to rotate, flip, or transpose an image.
+The result of the method is a copy of the image.
+
+=item B<$image-E<gt>rotate180()>
+
+=item B<$image-E<gt>flipHorizontal()>
+
+=item B<$image-E<gt>flipVertical()>
+
+These methods are similar to the copy* versions, but instead
+modify the image in place.
+
+=back
+
+=head2 Character and String Drawing
+
+GD allows you to draw characters and strings, either in normal
+horizontal orientation or rotated 90 degrees. These routines use a
+GD::Font object, described in more detail below. There are four
+built-in monospaced fonts, available in the global variables
+B<gdGiantFont>, B<gdLargeFont>, B<gdMediumBoldFont>, B<gdSmallFont>
+and B<gdTinyFont>.
+
+In addition, you can use the load() method to load GD-formatted bitmap
+font files at runtime. You can create these bitmap files from X11
+BDF-format files using the bdf2gd.pl script, which should have been
+installed with GD (see the bdf_scripts directory if it wasn't). The
+format happens to be identical to the old-style MSDOS bitmap ".fnt"
+files, so you can use one of those directly if you happen to have one.
+
+For writing proportional scaleable fonts, GD offers the stringFT()
+method, which allows you to load and render any TrueType font on your
+system.
+
+=over 4
+
+=item B<$image-E<gt>string($font,$x,$y,$string,$color)>
+
+This method draws a string starting at position (x,y) in the specified
+font and color. Your choices of fonts are gdSmallFont, gdMediumBoldFont,
+gdTinyFont, gdLargeFont and gdGiantFont.
+
+Example:
+
+ $myImage->string(gdSmallFont,2,10,"Peachy Keen",$peach);
+
+=item B<$image-E<gt>stringUp($font,$x,$y,$string,$color)>
+
+Just like the previous call, but draws the text rotated
+counterclockwise 90 degrees.
+
+=item B<$image-E<gt>char($font,$x,$y,$char,$color)>
+
+=item B<$image-E<gt>charUp($font,$x,$y,$char,$color)>
+
+These methods draw single characters at position (x,y) in the
+specified font and color. They're carry-overs from the C interface,
+where there is a distinction between characters and strings. Perl is
+insensible to such subtle distinctions.
+
+=item $font = B<GD::Font-E<gt>load($fontfilepath)>
+
+This method dynamically loads a font file, returning a font that you
+can use in subsequent calls to drawing methods. For example:
+
+ my $courier = GD::Font->load('./courierR12.fnt') or die "Can't load font";
+ $image->string($courier,2,10,"Peachy Keen",$peach);
+
+Font files must be in GD binary format, as described above.
+
+=item B<@bounds = $image-E<gt>stringFT($fgcolor,$fontname,$ptsize,$angle,$x,$y,$string)>
+
+=item B<@bounds = GD::Image-E<gt>stringFT($fgcolor,$fontname,$ptsize,$angle,$x,$y,$string)>
+
+=item B<@bounds = $image-E<gt>stringFT($fgcolor,$fontname,$ptsize,$angle,$x,$y,$string,\%options)>
+
+This method uses TrueType to draw a scaled, antialiased string using
+the TrueType vector font of your choice. It requires that libgd to
+have been compiled with TrueType support, and for the appropriate
+TrueType font to be installed on your system.
+
+The arguments are as follows:
+
+ fgcolor Color index to draw the string in
+ fontname A path to the TrueType (.ttf) font file or a font pattern.
+ ptsize The desired point size (may be fractional)
+ angle The rotation angle, in radians (positive values rotate counter clockwise)
+ x,y X and Y coordinates to start drawing the string
+ string The string itself
+
+If successful, the method returns an eight-element list giving the
+boundaries of the rendered string:
+
+ @bounds[0,1] Lower left corner (x,y)
+ @bounds[2,3] Lower right corner (x,y)
+ @bounds[4,5] Upper right corner (x,y)
+ @bounds[6,7] Upper left corner (x,y)
+
+In case of an error (such as the font not being available, or FT
+support not being available), the method returns an empty list and
+sets $@ to the error message.
+
+The string may contain UTF-8 sequences like: "&#192;"
+
+You may also call this method from the GD::Image class name, in which
+case it doesn't do any actual drawing, but returns the bounding box
+using an inexpensive operation. You can use this to perform layout
+operations prior to drawing.
+
+Using a negative color index will disable antialiasing, as described
+in the libgd manual page at
+L<http://www.boutell.com/gd/manual2.0.9.html#gdImageStringFT>.
+
+An optional 8th argument allows you to pass a hashref of options to
+stringFT(). Several hashkeys are recognized: B<linespacing>,
+B<charmap>, B<resolution>, and B<kerning>.
+
+The value of B<linespacing> is supposed to be a multiple of the
+character height, so setting linespacing to 2.0 will result in
+double-spaced lines of text. However the current version of libgd
+(2.0.12) does not do this. Instead the linespacing seems to be double
+what is provided in this argument. So use a spacing of 0.5 to get
+separation of exactly one line of text. In practice, a spacing of 0.6
+seems to give nice results. Another thing to watch out for is that
+successive lines of text should be separated by the "\r\n" characters,
+not just "\n".
+
+The value of B<charmap> is one of "Unicode", "Shift_JIS" and "Big5".
+The interaction between Perl, Unicode and libgd is not clear to me,
+and you should experiment a bit if you want to use this feature.
+
+The value of B<resolution> is the vertical and horizontal resolution,
+in DPI, in the format "hdpi,vdpi". If present, the resolution will be
+passed to the Freetype rendering engine as a hint to improve the
+appearance of the rendered font.
+
+The value of B<kerning> is a flag. Set it to false to turn off the
+default kerning of text.
+
+Example:
+
+ $gd->stringFT($black,'/dosc/windows/Fonts/pala.ttf',40,0,20,90,
+ "hi there\r\nbye now",
+ {linespacing=>0.6,
+ charmap => 'Unicode',
+ });
+
+If GD was compiled with fontconfig support, and the fontconfig library
+is available on your system, then you can use a font name pattern
+instead of a path. Patterns are described in L<fontconfig> and will
+look something like this "Times:italic". For backward
+compatibility, this feature is disabled by default. You must enable
+it by calling useFontConfig(1) prior to the stringFT() call.
+
+ $image->useFontConfig(1);
+
+For backward compatibility with older versions of the FreeType
+library, the alias stringTTF() is also recognized.
+
+=item B<$hasfontconfig = $image-E<gt>useFontConfig($flag)>
+
+Call useFontConfig() with a value of 1 in order to enable support for
+fontconfig font patterns (see stringFT). Regardless of the value of
+$flag, this method will return a true value if the fontconfig library
+is present, or false otherwise.
+
+=item B<$result = $image->stringFTCircle($cx,$cy,$radius,$textRadius,$fillPortion,$font,$points,$top,$bottom,$fgcolor)>
+
+This draws text in a circle. Currently (libgd 2.0.33) this function
+does not work for me, but the interface is provided for completeness.
+The call signature is somewhat complex. Here is an excerpt from the
+libgd manual page:
+
+Draws the text strings specified by top and bottom on the image, curved along
+the edge of a circle of radius radius, with its center at cx and
+cy. top is written clockwise along the top; bottom is written
+counterclockwise along the bottom. textRadius determines the "height"
+of each character; if textRadius is 1/2 of radius, characters extend
+halfway from the edge to the center. fillPortion varies from 0 to 1.0,
+with useful values from about 0.4 to 0.9, and determines how much of
+the 180 degrees of arc assigned to each section of text is actually
+occupied by text; 0.9 looks better than 1.0 which is rather
+crowded. font is a freetype font; see gdImageStringFT. points is
+passed to the freetype engine and has an effect on hinting; although
+the size of the text is determined by radius, textRadius, and
+fillPortion, you should pass a point size that "hints" appropriately
+-- if you know the text will be large, pass a large point size such as
+24.0 to get the best results. fgcolor can be any color, and may have
+an alpha component, do blending, etc.
+
+Returns a true value on success.
+
+=back
+
+=head2 Alpha channels
+
+The alpha channel methods allow you to control the way drawings are
+processed according to the alpha channel. When true color is turned
+on, colors are encoded as four bytes, in which the last three bytes
+are the RGB color values, and the first byte is the alpha channel.
+Therefore the hexadecimal representation of a non transparent RGB
+color will be: C=0x00(rr)(bb)(bb)
+
+When alpha blending is turned on, you can use the first byte of the
+color to control the transparency, meaning that a rectangle painted
+with color 0x00(rr)(bb)(bb) will be opaque, and another one painted
+with 0x7f(rr)(gg)(bb) will be transparent. The Alpha value must be >=
+0 and <= 0x7f.
+
+=over 4
+
+=item B<$image-E<gt>alphaBlending($integer)>
+
+The alphaBlending() method allows for two different modes of drawing
+on truecolor images. In blending mode, which is on by default (libgd
+2.0.2 and above), the alpha channel component of the color supplied to
+all drawing functions, such as C<setPixel>, determines how much of the
+underlying color should be allowed to shine through. As a result, GD
+automatically blends the existing color at that point with the drawing
+color, and stores the result in the image. The resulting pixel is
+opaque. In non-blending mode, the drawing color is copied literally
+with its alpha channel information, replacing the destination
+pixel. Blending mode is not available when drawing on palette images.
+
+Pass a value of 1 for blending mode, and 0 for non-blending mode.
+
+=item B<$image-E<gt>saveAlpha($saveAlpha)>
+
+By default, GD (libgd 2.0.2 and above) does not attempt to save full
+alpha channel information (as opposed to single-color transparency)
+when saving PNG images. (PNG is currently the only output format
+supported by gd which can accommodate alpha channel information.) This
+saves space in the output file. If you wish to create an image with
+alpha channel information for use with tools that support it, call
+C<saveAlpha(1)> to turn on saving of such information, and call
+C<alphaBlending(0)> to turn off alpha blending within the library so
+that alpha channel information is actually stored in the image rather
+than being composited immediately at the time that drawing functions
+are invoked.
+
+=back
+
+
+=head2 Miscellaneous Image Methods
+
+These are various utility methods that are useful in some
+circumstances.
+
+=over 4
+
+=item B<$image-E<gt>interlaced([$flag])>
+
+This method sets or queries the image's interlaced setting. Interlace
+produces a cool venetian blinds effect on certain viewers. Provide a
+true parameter to set the interlace attribute. Provide undef to
+disable it. Call the method without parameters to find out the
+current setting.
+
+=item B<($width,$height) = $image-E<gt>getBounds()>
+
+This method will return a two-member list containing the width and
+height of the image. You query but not change the size of the
+image once it's created.
+
+=item B<$width = $image-E<gt>width>
+
+=item B<$height = $image-E<gt>height>
+
+Return the width and height of the image, respectively.
+
+=item B<$is_truecolor = $image-E<gt>isTrueColor()>
+
+This method will return a Boolean representing whether the image
+is true color or not.
+
+=item B<$flag = $image1-E<gt>compare($image2)>
+
+Compare two images and return a bitmap describing the differences
+found, if any. The return value must be logically ANDed with one or
+more constants in order to determine the differences. The following
+constants are available:
+
+ GD_CMP_IMAGE The two images look different
+ GD_CMP_NUM_COLORS The two images have different numbers of colors
+ GD_CMP_COLOR The two images' palettes differ
+ GD_CMP_SIZE_X The two images differ in the horizontal dimension
+ GD_CMP_SIZE_Y The two images differ in the vertical dimension
+ GD_CMP_TRANSPARENT The two images have different transparency
+ GD_CMP_BACKGROUND The two images have different background colors
+ GD_CMP_INTERLACE The two images differ in their interlace
+ GD_CMP_TRUECOLOR The two images are not both true color
+
+The most important of these is GD_CMP_IMAGE, which will tell you
+whether the two images will look different, ignoring differences in the
+order of colors in the color palette and other invisible changes. The
+constants are not imported by default, but must be imported individually
+or by importing the :cmp tag. Example:
+
+ use GD qw(:DEFAULT :cmp);
+ # get $image1 from somewhere
+ # get $image2 from somewhere
+ if ($image1->compare($image2) & GD_CMP_IMAGE) {
+ warn "images differ!";
+ }
+
+=item B<$image-E<gt>clip($x1,$y1,$x2,$y2)>
+
+=item B<($x1,$y1,$x2,$y2) = $image-E<gt>clip>
+
+Set or get the clipping rectangle. When the clipping rectangle is
+set, all drawing will be clipped to occur within this rectangle. The
+clipping rectangle is initially set to be equal to the boundaries of
+the whole image. Change it by calling clip() with the coordinates of
+the new clipping rectangle. Calling clip() without any arguments will
+return the current clipping rectangle.
+
+=item B<$flag = $image-E<gt>boundsSafe($x,$y)>
+
+The boundsSafe() method will return true if the point indicated by
+($x,$y) is within the clipping rectangle, or false if it is not. If
+the clipping rectangle has not been set, then it will return true if
+the point lies within the image boundaries.
+
+=back
+
+=head2 Grouping Methods
+
+GD does not support grouping of objects, but GD::SVG does. In that
+subclass, the following methods declare new groups of graphical
+objects:
+
+=over 4
+
+=item $image->startGroup([$id,\%style])
+
+=item $image->endGroup()
+
+=item $group = $image->newGroup
+
+See L<GD::SVG> for information.
+
+=back
+
+=head1 Polygons
+
+A few primitive polygon creation and manipulation methods are
+provided. They aren't part of the Gd library, but I thought they
+might be handy to have around (they're borrowed from my qd.pl
+Quickdraw library). Also see L<GD::Polyline>.
+
+=over 3
+
+=item B<$poly = GD::Polygon-E<gt>new>
+
+Create an empty polygon with no vertices.
+
+ $poly = new GD::Polygon;
+
+=item B<$poly-E<gt>addPt($x,$y)>
+
+Add point (x,y) to the polygon.
+
+ $poly->addPt(0,0);
+ $poly->addPt(0,50);
+ $poly->addPt(25,25);
+ $myImage->fillPoly($poly,$blue);
+
+=item B<($x,$y) = $poly-E<gt>getPt($index)>
+
+Retrieve the point at the specified vertex.
+
+ ($x,$y) = $poly->getPt(2);
+
+=item B<$poly-E<gt>setPt($index,$x,$y)>
+
+Change the value of an already existing vertex. It is an error to set
+a vertex that isn't already defined.
+
+ $poly->setPt(2,100,100);
+
+=item B<($x,$y) = $poly-E<gt>deletePt($index)>
+
+Delete the specified vertex, returning its value.
+
+ ($x,$y) = $poly->deletePt(1);
+
+
+=item B<$poly-E<gt>clear()>
+
+Delete all vertices, restoring the polygon to its initial empty state.
+
+=item B<$poly-E<gt>toPt($dx,$dy)>
+
+Draw from current vertex to a new vertex, using relative (dx,dy)
+coordinates. If this is the first point, act like addPt().
+
+ $poly->addPt(0,0);
+ $poly->toPt(0,50);
+ $poly->toPt(25,-25);
+ $myImage->fillPoly($poly,$blue);
+
+=item B<$vertex_count = $poly-E<gt>length>
+
+Return the number of vertices in the polygon.
+
+ $points = $poly->length;
+
+=item B<@vertices = $poly-E<gt>vertices>
+
+Return a list of all the vertices in the polygon object. Each member
+of the list is a reference to an (x,y) array.
+
+ @vertices = $poly->vertices;
+ foreach $v (@vertices)
+ print join(",",@$v),"\n";
+ }
+
+=item B<@rect = $poly-E<gt>bounds>
+
+Return the smallest rectangle that completely encloses the polygon.
+The return value is an array containing the (left,top,right,bottom) of
+the rectangle.
+
+ ($left,$top,$right,$bottom) = $poly->bounds;
+
+=item B<$poly-E<gt>offset($dx,$dy)>
+
+Offset all the vertices of the polygon by the specified horizontal
+(dh) and vertical (dy) amounts. Positive numbers move the polygon
+down and to the right.
+
+ $poly->offset(10,30);
+
+=item B<$poly-E<gt>map($srcL,$srcT,$srcR,$srcB,$destL,$dstT,$dstR,$dstB)>
+
+Map the polygon from a source rectangle to an equivalent position in a
+destination rectangle, moving it and resizing it as necessary. See
+polys.pl for an example of how this works. Both the source and
+destination rectangles are given in (left,top,right,bottom)
+coordinates. For convenience, you can use the polygon's own bounding
+box as the source rectangle.
+
+ # Make the polygon really tall
+ $poly->map($poly->bounds,0,0,50,200);
+
+=item B<$poly-E<gt>scale($sx,$sy)>
+
+Scale each vertex of the polygon by the X and Y factors indicated by
+sx and sy. For example scale(2,2) will make the polygon twice as
+large. For best results, move the center of the polygon to position
+(0,0) before you scale, then move it back to its previous position.
+
+=item B<$poly-E<gt>transform($sx,$rx,$sy,$ry,$tx,$ty)>
+
+Run each vertex of the polygon through a transformation matrix, where
+sx and sy are the X and Y scaling factors, rx and ry are the X and Y
+rotation factors, and tx and ty are X and Y offsets. See the Adobe
+PostScript Reference, page 154 for a full explanation, or experiment.
+
+=back
+
+=head2 GD::Polyline
+
+Please see L<GD::Polyline> for information on creating open polygons
+and splines.
+
+=head1 Font Utilities
+
+The libgd library (used by the Perl GD library) has built-in support
+for about half a dozen fonts, which were converted from public-domain
+X Windows fonts. For more fonts, compile libgd with TrueType support
+and use the stringFT() call.
+
+If you wish to add more built-in fonts, the directory bdf_scripts
+contains two contributed utilities that may help you convert X-Windows
+BDF-format fonts into the format that libgd uses internally. However
+these scripts were written for earlier versions of GD which included
+its own mini-gd library. These scripts will have to be adapted for
+use with libgd, and the libgd library itself will have to be
+recompiled and linked! Please do not contact me for help with these
+scripts: they are unsupported.
+
+Each of these fonts is available both as an imported global
+(e.g. B<gdSmallFont>) and as a package method
+(e.g. B<GD::Font-E<gt>Small>).
+
+=over 5
+
+=item B<gdSmallFont>
+
+=item B<GD::Font-E<gt>Small>
+
+This is the basic small font, "borrowed" from a well known public
+domain 6x12 font.
+
+=item B<gdLargeFont>
+
+=item B<GD::Font-E<gt>Large>
+
+This is the basic large font, "borrowed" from a well known public
+domain 8x16 font.
+
+=item B<gdMediumBoldFont>
+
+=item B<GD::Font-E<gt>MediumBold>
+
+This is a bold font intermediate in size between the small and large
+fonts, borrowed from a public domain 7x13 font;
+
+=item B<gdTinyFont>
+
+=item B<GD::Font-E<gt>Tiny>
+
+This is a tiny, almost unreadable font, 5x8 pixels wide.
+
+=item B<gdGiantFont>
+
+=item B<GD::Font-E<gt>Giant>
+
+This is a 9x15 bold font converted by Jan Pazdziora from a sans serif
+X11 font.
+
+=item B<$font-E<gt>nchars>
+
+This returns the number of characters in the font.
+
+ print "The large font contains ",gdLargeFont->nchars," characters\n";
+
+=item B<$font-E<gt>offset>
+
+This returns the ASCII value of the first character in the font
+
+=item B<$width = $font-E<gt>width>
+
+=item B<$height = $font-E<gt>height>
+
+=item C<height>
+
+These return the width and height of the font.
+
+ ($w,$h) = (gdLargeFont->width,gdLargeFont->height);
+
+=back
+
+=head1 Obtaining the C-language version of gd
+
+libgd, the C-language version of gd, can be obtained at URL
+http://www.boutell.com/gd/. Directions for installing and using it
+can be found at that site. Please do not contact me for help with
+libgd.
+
+=head1 AUTHOR
+
+The GD.pm interface is copyright 1995-2007, Lincoln D. Stein. It is
+distributed under GPL and the Artistic License 2.0.
+
+The latest versions of GD.pm are available at
+
+ http://stein.cshl.org/WWW/software/GD
+
+=head1 SEE ALSO
+
+L<GD::Polyline>,
+L<GD::SVG>,
+L<GD::Simple>,
+L<Image::Magick>
+
+=cut
+
+1;
+
+__END__