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GD(3)		      User Contributed Perl Documentation		 GD(3)

NAME
       GD.pm - Interface to Gd Graphics Library

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;

DESCRIPTION
       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:

       "GD::Image"
	    An image class, which holds the image data and accepts graphic
	    primitive method calls.

       "GD::Font"
	    A font class, which holds static font information and used for
	    text rendering.

       "GD::Polygon"
	    A simple polygon object, used for storing lists of vertices prior
	    to rendering a polygon into an image.

       "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 GD::Simple for a description of these methods.

       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:

       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.
       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.
       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.
       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.
       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 "binmode()" on the file you are writing the
       image to.

Object Constructors: Creating Images
       The following class methods allow you to create new GD::Image objects.

       $image = GD::Image->new([$width,$height],[$truecolor])
       $image = GD::Image->new(*FILEHANDLE)
       $image = GD::Image->new($filename)
       $image = GD::Image->new($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.

       $image = GD::Image->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);

       $image = GD::Image->newPalette([$width,$height])
       $image = GD::Image->newTrueColor([$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().

       $image = GD::Image->newFromPng($file, [$truecolor])
       $image = GD::Image->newFromPngData($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 "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 data contained in $data.

       $image = GD::Image->newFromJpeg($file, [$truecolor])
       $image = GD::Image->newFromJpegData($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.

       $image = GD::Image->newFromGif($file)
       $image = GD::Image->newFromGifData($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.

       $image = GD::Image->newFromXbm($file)
	   This works in exactly the same way as "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.

       $image = GD::Image->newFromGd($file)
       $image = GD::Image->newFromGdData($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
	   BIG.

		   $myImage = newFromGd GD::Image("godzilla.gd") || die;
		   close GDF;

       $image = GD::Image->newFromGd2($file)
       $image = GD::Image->newFromGd2Data($data)
	   This works in exactly the same way as "newFromGd()" and
	   newFromGdData, but use the new compressed GD2 image format.

       $image = GD::Image->newFromGd2Part($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).

       $image = GD::Image->newFromXpm($filename)
	   This creates a new GD::Image object starting from a 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.

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.

   Image Data Output Methods
       The following methods convert the internal drawing format into standard
       output file formats.

       $pngdata = $image->png([$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 "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).

       $gifdata = $image->gifanimbegin([$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.

       $gifdata = $image->gifanimadd([$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.

       $gifdata = $image->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.

       $jpegdata = $image->jpeg([$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.

       $gifdata = $image->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.

       $gddata = $image->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;

       $gd2data = $image->gd2
	   Same as gd(), except that it returns the data in compressed GD2
	   format.

       $wbmpdata = $image->wbmp([$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.

   Color Control
       These methods allow you to control and manipulate the GD::Image color
       table.

       $index = $image->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);

       $index = $image->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 "alphaBlending"
	   function changes the way this alpha channel affects the resulting
	   image.

       $image->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);

       $index = $image->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);

       $index = $image->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);

       $index = $image->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;

       $index = $image->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;

       $colorsTotal = $image->colorsTotal 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.

       $index = $image->getPixel(x,y) 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);

       ($red,$green,$blue) = $image->rgb($index)
	   This returns a list containing the red, green and blue components
	   of the specified color index.

	   Example:

		   @RGB = $myImage->rgb($peachy);

       $image->transparent($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;

   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.

       $image->setBrush($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 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);

       $image->setThickness($thickness)
	   Lines drawn with line(), rectangle(), arc(), and so forth are 1
	   pixel thick by default.  Call setThickness() to change the line
	   drawing width.

       $image->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 gdStyled special color.  Another
	   special color, 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 "gdStyled" and "gdBrushed" behaviors, you can
	   specify "gdStyledBrushed".  In this case, a pixel from the current
	   brush pattern is rendered wherever the color specified in
	   setStyle() is neither gdTransparent nor 0.

       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 "setTile" in order to define the particular tile pattern
	   you'll use for drawing when you specify the gdTiled color.
	   details.

       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.

       gdAntiAliased
	   The "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().

       $image->setAntiAliased($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"
	   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.

       $image->setAntiAliasedDontBlend($color,[$flag])
	   Normally, when drawing lines with the special 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);

   Drawing Commands
       These methods allow you to draw lines, rectangles, and ellipses, as
       well as to perform various special operations like flood-fill.

       $image->setPixel($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);

       $image->line($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);

       $image->dashedLine($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);

       $image->rectangle($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);

       $image->filledRectangle($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);

       $image->openPolygon($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);

       $image->unclosedPolygon($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);

       $image->filledPolygon($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);

       $image->ellipse($cx,$cy,$width,$height,$color)
       $image->filledEllipse($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.

       $image->arc($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
	   gdBrushed, gdStyled, or gdStyledBrushed.

	   Example:

		   # draw a semicircle centered at 100,100
		   $myImage->arc(100,100,50,50,0,180,$blue);

       $image->filledArc($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);

       $image->fill($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);

       $image->fillToBorder($x,$y,$bordercolor,$color)
	   Like "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);

   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.

       $image->copy($sourceImage,$dstX,$dstY,
			       $srcX,$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);

       $image->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;

       $image->copyMerge($sourceImage,$dstX,$dstY,
			       $srcX,$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);

       $image->copyMergeGray($sourceImage,$dstX,$dstY,
			       $srcX,$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.

       $image->copyResized($sourceImage,$dstX,$dstY,
			       $srcX,$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);

       $image->copyResampled($sourceImage,$dstX,$dstY,
			       $srcX,$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.

       $image->copyRotated($sourceImage,$dstX,$dstY,
			       $srcX,$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 center of the destination image, and
	   not the top left corner.

       $image->trueColorToPalette([$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.

   Image Transformation Commands
       Gd also provides some common image transformations:

       $image = $sourceImage->copyRotate90()
       $image = $sourceImage->copyRotate180()
       $image = $sourceImage->copyRotate270()
       $image = $sourceImage->copyFlipHorizontal()
       $image = $sourceImage->copyFlipVertical()
       $image = $sourceImage->copyTranspose()
       $image = $sourceImage->copyReverseTranspose()
	   These methods can be used to rotate, flip, or transpose an image.
	   The result of the method is a copy of the image.

       $image->rotate180()
       $image->flipHorizontal()
       $image->flipVertical()
	   These methods are similar to the copy* versions, but instead modify
	   the image in place.

   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 gdGiantFont,
       gdLargeFont, gdMediumBoldFont, gdSmallFont and 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.

       $image->string($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);

       $image->stringUp($font,$x,$y,$string,$color)
	   Just like the previous call, but draws the text rotated
	   counterclockwise 90 degrees.

       $image->char($font,$x,$y,$char,$color)
       $image->charUp($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.

       $font = GD::Font->load($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.

       @bounds =
       $image->stringFT($fgcolor,$fontname,$ptsize,$angle,$x,$y,$string)
       @bounds =
       GD::Image->stringFT($fgcolor,$fontname,$ptsize,$angle,$x,$y,$string)
       @bounds =
       $image->stringFT($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: "À"

	   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
	   <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: linespacing, charmap,
	   resolution, and kerning.

	   The value of 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 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 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 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 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.

       $hasfontconfig = $image->useFontConfig($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.

       $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.

   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.

       $image->alphaBlending($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 "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.

       $image->saveAlpha($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 saveAlpha(1) to turn on saving of such
	   information, and call 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.

   Miscellaneous Image Methods
       These are various utility methods that are useful in some
       circumstances.

       $image->interlaced([$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.

       ($width,$height) = $image->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.

       $width = $image->width
       $height = $image->height
	   Return the width and height of the image, respectively.

       $is_truecolor = $image->isTrueColor()
	   This method will return a Boolean representing whether the image is
	   true color or not.

       $flag = $image1->compare($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!";
	     }

       $image->clip($x1,$y1,$x2,$y2)
       ($x1,$y1,$x2,$y2) = $image->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.

       $flag = $image->boundsSafe($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.

   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:

       $image->startGroup([$id,\%style])
       $image->endGroup()
       $group = $image->newGroup
	   See GD::SVG for information.

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 GD::Polyline.

       $poly = GD::Polygon->new
	  Create an empty polygon with no vertices.

		  $poly = new GD::Polygon;

       $poly->addPt($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);

       ($x,$y) = $poly->getPt($index)
	  Retrieve the point at the specified vertex.

		  ($x,$y) = $poly->getPt(2);

       $poly->setPt($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);

       ($x,$y) = $poly->deletePt($index)
	  Delete the specified vertex, returning its value.

		  ($x,$y) = $poly->deletePt(1);

       $poly->clear()
	  Delete all vertices, restoring the polygon to its initial empty
	  state.

       $poly->toPt($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);

       $vertex_count = $poly->length
	  Return the number of vertices in the polygon.

		  $points = $poly->length;

       @vertices = $poly->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";
		  }

       @rect = $poly->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;

       $poly->offset($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);

       $poly->map($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);

       $poly->scale($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.

       $poly->transform($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.

   GD::Polyline
       Please see GD::Polyline for information on creating open polygons and
       splines.

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.
       gdSmallFont) and as a package method (e.g. GD::Font->Small).

       gdSmallFont
       GD::Font->Small
	    This is the basic small font, "borrowed" from a well known public
	    domain 6x12 font.

       gdLargeFont
       GD::Font->Large
	    This is the basic large font, "borrowed" from a well known public
	    domain 8x16 font.

       gdMediumBoldFont
       GD::Font->MediumBold
	    This is a bold font intermediate in size between the small and
	    large fonts, borrowed from a public domain 7x13 font;

       gdTinyFont
       GD::Font->Tiny
	    This is a tiny, almost unreadable font, 5x8 pixels wide.

       gdGiantFont
       GD::Font->Giant
	    This is a 9x15 bold font converted by Jan Pazdziora from a sans
	    serif X11 font.

       $font->nchars
	    This returns the number of characters in the font.

		    print "The large font contains ",gdLargeFont->nchars," characters\n";

       $font->offset
	    This returns the ASCII value of the first character in the font

       $width = $font->width
       $height = $font->height
       "height"
	    These return the width and height of the font.

	      ($w,$h) = (gdLargeFont->width,gdLargeFont->height);

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.

AUTHOR
       The GD.pm interface is copyright 1995-2010, Lincoln D. Stein. This
       package and its accompanying libraries is free software; you can
       redistribute it and/or modify it under the terms of the GPL (either
       version 1, or at your option, any later version) or the Artistic
       License 2.0.  Refer to LICENSE for the full license text.  package for
       details.

       The latest versions of GD.pm are available at

	 http://stein.cshl.org/WWW/software/GD

SEE ALSO
       GD::Polyline, GD::SVG, GD::Simple, Image::Magick

POD ERRORS
       Hey! The above document had some coding errors, which are explained
       below:

       Around line 463:
	   You forgot a '=back' before '=head1'

       Around line 475:
	   '=item' outside of any '=over'

perl v5.16.3			  2013-02-26				 GD(3)
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