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diff GD/Simple.pm @ 0:58111b3965b2 draft default tip
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| author | dereeper |
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| date | Thu, 01 Nov 2012 09:35:05 -0400 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/GD/Simple.pm Thu Nov 01 09:35:05 2012 -0400 @@ -0,0 +1,1236 @@ +package GD::Simple; + +=head1 NAME + +GD::Simple - Simplified interface to GD library + +=head1 SYNOPSIS + + use GD::Simple; + + # create a new image + $img = GD::Simple->new(400,250); + + # draw a red rectangle with blue borders + $img->bgcolor('red'); + $img->fgcolor('blue'); + $img->rectangle(10,10,50,50); + + # draw an empty rectangle with green borders + $img->bgcolor(undef); + $img->fgcolor('green'); + $img->rectangle(30,30,100,100); + + # move to (80,80) and draw a green line to (100,190) + $img->moveTo(80,80); + $img->lineTo(100,190); + + # draw a solid orange ellipse + $img->moveTo(110,100); + $img->bgcolor('orange'); + $img->fgcolor('orange'); + $img->ellipse(40,40); + + # draw a black filled arc + $img->moveTo(150,150); + $img->fgcolor('black'); + $img->arc(50,50,0,100,gdNoFill|gdEdged); + + # draw a string at (10,180) using the default + # built-in font + $img->moveTo(10,180); + $img->string('This is very simple'); + + # draw a string at (280,210) using 20 point + # times italic, angled upward 90 degrees + $img->moveTo(280,210); + $img->font('Times:italic'); + $img->fontsize(20); + $img->angle(-90); + $img->string('This is very fancy'); + + # some turtle graphics + $img->moveTo(300,100); + $img->penSize(3,3); + $img->angle(0); + $img->line(20); # 20 pixels going to the right + $img->turn(30); # set turning angle to 30 degrees + $img->line(20); # 20 pixel line + $img->line(20); + $img->line(20); + $img->turn(-90); # set turning angle to -90 degrees + $img->line(50); # 50 pixel line + + # draw a cyan polygon edged in blue + my $poly = new GD::Polygon; + $poly->addPt(150,100); + $poly->addPt(199,199); + $poly->addPt(100,199); + $img->bgcolor('cyan'); + $img->fgcolor('blue'); + $img->penSize(1,1); + $img->polygon($poly); + + # convert into png data + print $img->png; + +=head1 DESCRIPTION + +GD::Simple is a subclass of the GD library that shortens many of the +long GD method calls by storing information about the pen color, size +and position in the GD object itself. It also adds a small number of +"turtle graphics" style calls for those who prefer to work in polar +coordinates. In addition, the library allows you to use symbolic +names for colors, such as "chartreuse", and will manage the colors for +you. + +=head2 The Pen + +GD::Simple maintains a "pen" whose settings are used for line- and +shape-drawing operations. The pen has the following properties: + +=over 4 + +=item fgcolor + +The pen foreground color is the color of lines and the borders of +filled and unfilled shapes. + +=item bgcolor + +The pen background color is the color of the contents of filled +shapes. + +=item pensize + +The pen size is the width of the pen. Larger sizes draw thicker +lines. + +=item position + +The pen position is its current position on the canvas in (X,Y) +coordinates. + +=item angle + +When drawing in turtle mode, the pen angle determines the current +direction of lines of relative length. + +=item turn + +When drawing in turtle mode, the turn determines the clockwise or +counterclockwise angle that the pen will turn before drawing the next +line. + +=item font + +The font to use when drawing text. Both built-in bitmapped fonts and +TrueType fonts are supported. + +=item fontsize + +The size of the font to use when drawing with TrueType fonts. + +=back + +One sets the position and properties of the pen and then draws. As +the drawing progresses, the position of the pen is updated. + +=head2 Methods + +GD::Simple introduces a number of new methods, a few of which have the +same name as GD::Image methods, and hence change their behavior. In +addition to these new methods, GD::Simple objects support all of the +GD::Image methods. If you make a method call that isn't directly +supported by GD::Simple, it refers the request to the underlying +GD::Image object. Hence one can load a JPEG image into GD::Simple and +declare it to be TrueColor by using this call, which is effectively +inherited from GD::Image: + + my $img = GD::Simple->newFromJpeg('./myimage.jpg',1); + +The rest of this section describes GD::Simple-specific methods. + +=cut + +use strict; +use GD; +use GD::Group; +use Math::Trig; +use Carp 'croak'; + +our @ISA = 'Exporter'; +our @EXPORT = @GD::EXPORT; +our @EXPORT_OK = @GD::EXPORT_OK; +our $AUTOLOAD; + +my %COLORS; +my $IMAGECLASS = 'GD::Image'; +my $TRANSPARENT; + +sub AUTOLOAD { + my $self = shift; + my($pack,$func_name) = $AUTOLOAD=~/(.+)::([^:]+)$/; + return if $func_name eq 'DESTROY'; + + if (ref $self && exists $self->{gd}) { + $self->{gd}->$func_name(@_); + } else { + my @result = $IMAGECLASS->$func_name(@_); + if (UNIVERSAL::isa($result[0],'GD::Image')) { + return $self->new($result[0]); + } else { + return @result; + } + } +} + +=over 4 + +=item $img = GD::Simple->new($x,$y [,$truecolor]) + +=item $img = GD::Simple->new($gd) + +Create a new GD::Simple object. There are two forms of new(). In the +first form, pass the width and height of the desired canvas, and +optionally a boolean flag to request a truecolor image. In the second +form, pass a previously-created GD::Image object. + +=cut + +# dual-purpose code - beware +sub new { + my $pack = shift; + + unshift @_,(100,100) if @_ == 0; + + if (@_ >= 2) { # traditional GD::Image->new() call + my $gd = $IMAGECLASS->new(@_); + my $self = $pack->new($gd); + $self->clear; + return $self; + } + + if (@_ == 1) { # initialize from existing image + my $gd = shift; + my $self = bless { + gd => $gd, + xy => [0,0], + font => gdSmallFont, + fontsize => 9, + turningangle => 0, + angle => 0, + pensize => 1, + },$pack; + $self->{bgcolor} = $self->translate_color(255,255,255); + $self->{fgcolor} = $self->translate_color(0,0,0); + return $self; + } +} + +=item GD::Simple->class('GD'); + +=item GD::Simple->class('GD::SVG'); + +Select whether new() should use GD or GD::SVG internally. Call +GD::Simple->class('GD::SVG') before calling new() if you wish to +generate SVG images. + +If future GD subclasses are created, this method will subport them. + +=cut + +sub class { + my $pack = shift; + if (@_) { + $IMAGECLASS = shift; + eval "require $IMAGECLASS; 1" or die $@; + $IMAGECLASS = "$IMAGECLASS\:\:Image" + if $IMAGECLASS eq 'GD::SVG'; + } + $IMAGECLASS; +} + +=item $img->moveTo($x,$y) + +This call changes the position of the pen without drawing. It moves +the pen to position ($x,$y) on the drawing canvas. + +=cut + +sub moveTo { + my $self = shift; + croak 'Usage GD::Simple->moveTo($x,$y)' unless @_ == 2; + my ($x,$y) = @_; + $self->{xy} = [$x,$y]; +} + +=item $img->move($dx,$dy) + +=item $img->move($dr) + +This call changes the position of the pen without drawing. When called +with two arguments it moves the pen $dx pixels to the right and $dy +pixels downward. When called with one argument it moves the pen $dr +pixels along the vector described by the current pen angle. + +=cut + +sub move { + my $self = shift; + if (@_ == 1) { # polar coordinates -- this is r + $self->{angle} += $self->{turningangle}; + my $angle = deg2rad($self->{angle}); + $self->{xy}[0] += $_[0] * cos($angle); + $self->{xy}[1] += $_[0] * sin($angle); + } + elsif (@_ == 2) { # cartesian coordinates + $self->{xy}[0] += $_[0]; + $self->{xy}[1] += $_[1]; + } else { + croak 'Usage GD::Simple->move($dx,$dy) or move($r)'; + } +} + +=item $img->lineTo($x,$y) + +The lineTo() call simultaneously draws and moves the pen. It draws a +line from the current pen position to the position defined by ($x,$y) +using the current pen size and color. After drawing, the position of +the pen is updated to the new position. + +=cut + +sub lineTo { + my $self = shift; + croak 'Usage GD::Simple->lineTo($x,$y)' unless @_ == 2; + $self->gd->line($self->curPos,@_,$self->fgcolor); + $self->moveTo(@_); +} + +=item $img->line($dx,$dy) + +=item $img->line($dr) + +The line() call simultaneously draws and moves the pen. When called +with two arguments it draws a line from the current position of the +pen to the position $dx pixels to the right and $dy pixels down. When +called with one argument, it draws a line $dr pixels long along the +angle defined by the current pen angle. + +=cut + +sub line { + my $self = shift; + croak 'Usage GD::Simple->line($dx,$dy) or line($r)' unless @_ >= 1; + my @curPos = $self->curPos; + $self->move(@_); + my @newPos = $self->curPos; + $self->gd->line(@curPos,@newPos,$self->fgcolor); +} + +=item $img->clear + +This method clears the canvas by painting over it with the current +background color. + +=cut + +sub clear { + my $self = shift; + $self->gd->filledRectangle(0,0,$self->getBounds,$self->bgcolor); +} + +=item $img->rectangle($x1,$y1,$x2,$y2) + +This method draws the rectangle defined by corners ($x1,$y1), +($x2,$y2). The rectangle's edges are drawn in the foreground color and +its contents are filled with the background color. To draw a solid +rectangle set bgcolor equal to fgcolor. To draw an unfilled rectangle +(transparent inside), set bgcolor to undef. + +=cut + +sub rectangle { + my $self = shift; + croak 'Usage GD::Simple->rectangle($x1,$y1,$x2,$y2)' unless @_ == 4; + my $gd = $self->gd; + my ($bg,$fg) = ($self->bgcolor,$self->fgcolor); + $gd->filledRectangle(@_,$bg) if defined $bg; + $gd->rectangle(@_,$fg) if defined $fg && (!defined $bg || $bg != $fg); +} + +=item $img->ellipse($width,$height) + +This method draws the ellipse centered at the current location with +width $width and height $height. The ellipse's border is drawn in the +foreground color and its contents are filled with the background +color. To draw a solid ellipse set bgcolor equal to fgcolor. To draw +an unfilled ellipse (transparent inside), set bgcolor to undef. + +=cut + +sub ellipse { + my $self = shift; + croak 'Usage GD::Simple->ellipse($width,$height)' unless @_ == 2; + my $gd = $self->gd; + my ($bg,$fg) = ($self->bgcolor,$self->fgcolor); + $gd->filledEllipse($self->curPos,@_,$bg) if defined $bg; + $gd->ellipse($self->curPos,@_,$fg) if defined $fg && (!defined $bg || $bg != $fg); +} + +=item $img->arc($cx,$cy,$width,$height,$start,$end [,$style]) + +This method draws filled and unfilled arcs. See L<GD> for a +description of the arguments. To draw a solid arc (such as a pie +wedge) set bgcolor equal to fgcolor. To draw an unfilled arc, set +bgcolor to undef. + +=cut + +sub arc { + my $self = shift; + croak 'Usage GD::Simple->arc($width,$height,$start,$end,$style)' unless @_ >= 4; + my ($width,$height,$start,$end,$style) = @_; + my $gd = $self->gd; + my ($bg,$fg) = ($self->bgcolor,$self->fgcolor); + my ($cx,$cy) = $self->curPos; + + if ($bg) { + my @args = ($cx,$cy,$width,$height,$start,$end,$bg); + push @args,$style if defined $style; + $gd->filledArc(@args); + } else { + my @args = ($cx,$cy,$width,$height,$start,$end,$fg); + $gd->arc(@args); + } +} + +=item $img->polygon($poly) + +This method draws filled and unfilled polygon using the current +settings of fgcolor for the polygon border and bgcolor for the polygon +fill color. See L<GD> for a description of creating polygons. To draw +a solid polygon set bgcolor equal to fgcolor. To draw an unfilled +polygon, set bgcolor to undef. + +=cut + +sub polygon { + my $self = shift; + croak 'Usage GD::Simple->polygon($poly)' unless @_ == 1; + my $gd = $self->gd; + my ($bg,$fg) = ($self->bgcolor,$self->fgcolor); + $gd->filledPolygon(@_,$bg) if defined $bg; + $gd->openPolygon(@_,$fg) if defined $fg && (!defined $bg || $bg != $fg); +} + +=item $img->polyline($poly) + +This method draws polygons without closing the first and last vertices +(similar to GD::Image->unclosedPolygon()). It uses the fgcolor to draw +the line. + +=cut + +sub polyline { + my $self = shift; + croak 'Usage GD::Simple->polyline($poly)' unless @_ == 1; + my $gd = $self->gd; + my $fg = $self->fgcolor; + $gd->unclosedPolygon(@_,$fg); +} + +=item $img->string($string) + +This method draws the indicated string starting at the current +position of the pen. The pen is moved to the end of the drawn string. +Depending on the font selected with the font() method, this will use +either a bitmapped GD font or a TrueType font. The angle of the pen +will be consulted when drawing the text. For TrueType fonts, any angle +is accepted. For GD bitmapped fonts, the angle can be either 0 (draw +horizontal) or -90 (draw upwards). + +For consistency between the TrueType and GD font behavior, the string +is always drawn so that the current position of the pen corresponds to +the bottom left of the first character of the text. This is different +from the GD behavior, in which the first character of bitmapped fonts +hangs down from the pen point. + +This method returns a polygon indicating the bounding box of the +rendered text. If an error occurred (such as invalid font +specification) it returns undef and an error message in $@. + +=cut + +sub string { + my $self = shift; + my $string = shift; + my $font = $self->font; + my @bounds; + if (ref $font && $font->isa('GD::Font')) { + my ($x,$y) = $self->curPos; + if ($self->angle == -90) { + $x -= $font->height; + $y -= $font->width; + $self->gd->stringUp($font,$x,$y,$string,$self->fgcolor); + $self->{xy}[1] -= length($string) * $font->width; + @bounds = ( ($self->{xy}[0],$y), ($x,$y), ($x,$self->{xy}[1]-$font->width), ($self->{xy}[0],$self->{xy}[1]-$font->width) ); + } else { + $y -= $font->height; + $self->gd->string($font,$x,$y,$string,$self->fgcolor); + $self->{xy}[0] += length($string) * $font->width; + @bounds = ( ($x,$self->{xy}[1]), ($self->{xy}[0],$self->{xy}[1]), ($self->{xy}[0],$y), ($x,$y) ); + } + } + else { + $self->useFontConfig(1); + @bounds = $self->stringFT($self->fgcolor,$font, + $self->fontsize,-deg2rad($self->angle), # -pi * $self->angle/180, + $self->curPos,$string); + return unless @bounds; + my ($delta_x,$delta_y) = $self->_string_width(@bounds); + $self->{xy}[0] += $delta_x; + $self->{xy}[1] += $delta_y; + } + my $poly = GD::Polygon->new; + while (@bounds) { + $poly->addPt(splice(@bounds,0,2)); + } + return $poly; +} + +=item $metrics = $img->fontMetrics + +=item ($metrics,$width,$height) = GD::Simple->fontMetrics($font,$fontsize,$string) + +This method returns information about the current font, most commonly +a TrueType font. It can be invoked as an instance method (on a +previously-created GD::Simple object) or as a class method (on the +'GD::Simple' class). + +When called as an instance method, fontMetrics() takes no arguments +and returns a single hash reference containing the metrics that +describe the currently selected font and size. The hash reference +contains the following information: + + xheight the base height of the font from the bottom to the top of + a lowercase 'm' + + ascent the length of the upper stem of the lowercase 'd' + + descent the length of the lower step of the lowercase 'j' + + lineheight the distance from the bottom of the 'j' to the top of + the 'd' + + leading the distance between two adjacent lines + +=cut + +# return %$fontmetrics +# keys: 'ascent', 'descent', 'lineheight', 'xheight', 'leading' +sub fontMetrics { + my $self = shift; + + unless (ref $self) { #class invocation -- create a scratch + $self = $self->new; + $self->font(shift) if defined $_[0]; + $self->fontsize(shift) if defined $_[0]; + } + + my $font = $self->font; + my $metrics; + + if (ref $font && $font->isa('GD::Font')) { + my $height = $font->height; + $metrics = {ascent => 0, + descent => 0, + lineheight => $height, + xheight => $height, + leading => 0}; + } + else { + $self->useFontConfig(1); + my @mbounds = GD::Image->stringFT($self->fgcolor,$font, + $self->fontsize,0, + 0,0,'m'); + my $xheight = $mbounds[3]-$mbounds[5]; + my @jbounds = GD::Image->stringFT($self->fgcolor,$font, + $self->fontsize,0, + 0,0,'j'); + my $ascent = $mbounds[7]-$jbounds[7]; + my $descent = $jbounds[3]-$mbounds[3]; + + my @mmbounds = GD::Image->stringFT($self->fgcolor,$font, + $self->fontsize,0, + 0,0,"m\nm"); + my $twolines = $mmbounds[3]-$mmbounds[5]; + my $lineheight = $twolines - 2*$xheight; + my $leading = $lineheight - $ascent - $descent; + $metrics = {ascent => $ascent, + descent => $descent, + lineheight => $lineheight, + xheight => $xheight, + leading => $leading}; + } + + if ((my $string = shift) && wantarray) { + my ($width,$height) = $self->stringBounds($string); + return ($metrics,abs($width),abs($height)); + } + return $metrics; +} + +=item ($delta_x,$delta_y)= $img->stringBounds($string) + +This method indicates the X and Y offsets (which may be negative) that +will occur when the given string is drawn using the current font, +fontsize and angle. When the string is drawn horizontally, it gives +the width and height of the string's bounding box. + +=cut + +sub stringBounds { + my $self = shift; + my $string = shift; + my $font = $self->font; + if (ref $font && $font->isa('GD::Font')) { + if ($self->angle == -90) { + return ($font->height,-length($string) * $font->width); + } else { + return (length($string) * $font->width,$font->height); + } + } + else { + $self->useFontConfig(1); + my @bounds = GD::Image->stringFT($self->fgcolor,$font, + $self->fontsize,-deg2rad($self->angle), + $self->curPos,$string); + return $self->_string_width(@bounds); + } +} + +=item $delta_x = $img->stringWidth($string) + +This method indicates the width of the string given the current font, +fontsize and angle. It is the same as ($img->stringBounds($string))[0] + +=cut + +sub stringWidth { + return ((shift->stringBounds(@_))[0]); +} + + +sub _string_width { + my $self = shift; + my @bounds = @_; + my $delta_x = abs($bounds[2]-$bounds[0]); + my $delta_y = abs($bounds[5]-$bounds[3]); + my $angle = $self->angle % 360; + if ($angle >= 0 && $angle < 90) { + return ($delta_x,$delta_y); + + } elsif ($angle >= 90 && $angle < 180) { + return (-$delta_x,$delta_y); + + } elsif ($angle >= 180 && $angle < 270) { + return (-$delta_x,-$delta_y); + + } elsif ($angle >= 270 && $angle < 360) { + return ($delta_x,-$delta_y); + } +} + +=item ($x,$y) = $img->curPos + +Return the current position of the pen. Set the current position +using moveTo(). + +=cut + +sub curPos { @{shift->{xy}}; } + +=item $font = $img->font([$newfont] [,$newsize]) + +Get or set the current font. Fonts can be GD::Font objects, TrueType +font file paths, or fontconfig font patterns like "Times:italic" (see +L<fontconfig>). The latter feature requires that you have the +fontconfig library installed and are using libgd version 2.0.33 or +higher. + +As a shortcut, you may pass two arguments to set the font and the +fontsize simultaneously. The fontsize is only valid when drawing with +TrueType fonts. + +=cut + +sub font { + my $self = shift; + $self->{font} = shift if @_; + $self->{fontsize} = shift if @_; + $self->{font}; +} + +=item $size = $img->fontsize([$newfontsize]) + +Get or set the current font size. This is only valid for TrueType +fonts. + +=cut + +sub fontsize { + my $self = shift; + $self->{fontsize} = shift if @_; + $self->{fontsize}; +} + +=item $size = $img->penSize([$newpensize]) + +Get or set the current pen width for use during line drawing +operations. + +=cut + +sub penSize { + my $self = shift; + if (@_) { + $self->{pensize} = shift; + $self->gd->setThickness($self->{pensize}); + } + $self->{pensize}; +} + +=item $angle = $img->angle([$newangle]) + +Set the current angle for use when calling line() or move() with a +single argument. + +Here is an example of using turn() and angle() together to draw an +octagon. The first line drawn is the downward-slanting top right +edge. The last line drawn is the horizontal top of the octagon. + + $img->moveTo(200,50); + $img->angle(0); + $img->turn(360/8); + for (1..8) { $img->line(50) } + +=cut + +sub angle { + my $self = shift; + $self->{angle} = shift if @_; + $self->{angle}; +} + +=item $angle = $img->turn([$newangle]) + +Get or set the current angle to turn prior to drawing lines. This +value is only used when calling line() or move() with a single +argument. The turning angle will be applied to each call to line() or +move() just before the actual drawing occurs. + +Angles are in degrees. Positive values turn the angle clockwise. + +=cut + +# degrees, not radians +sub turn { + my $self = shift; + $self->{turningangle} = shift if @_; + $self->{turningangle}; +} + +=item $color = $img->fgcolor([$newcolor]) + +Get or set the pen's foreground color. The current pen color can be +set by (1) using an (r,g,b) triple; (2) using a previously-allocated +color from the GD palette; or (3) by using a symbolic color name such +as "chartreuse." The list of color names can be obtained using +color_names(). The special color name 'transparent' will create a +completely transparent color. + +=cut + +sub fgcolor { + my $self = shift; + $self->{fgcolor} = $self->translate_color(@_) if @_; + $self->{fgcolor}; +} + +=item $color = $img->bgcolor([$newcolor]) + +Get or set the pen's background color. The current pen color can be +set by (1) using an (r,g,b) triple; (2) using a previously-allocated +color from the GD palette; or (3) by using a symbolic color name such +as "chartreuse." The list of color names can be obtained using +color_names(). The special color name 'transparent' will create a +completely transparent color. + +=cut + +sub bgcolor { + my $self = shift; + $self->{bgcolor} = $self->translate_color(@_) if @_; + $self->{bgcolor}; +} + +=item $index = $img->translate_color(@args) + +Translates a color into a GD palette or TrueColor index. You may pass +either an (r,g,b) triple or a symbolic color name. If you pass a +previously-allocated index, the method will return it unchanged. + +=cut + +sub translate_color { + my $self = shift; + return unless defined $_[0]; + my ($r,$g,$b); + if (@_ == 1 && $_[0] =~ /^-?\d+/) { # previously allocated index + return $_[0]; + } + elsif (@_ == 3) { # (rgb triplet) + ($r,$g,$b) = @_; + } + elsif (lc $_[0] eq 'transparent') { + return $TRANSPARENT ||= $self->alphaColor('white',127); + } + else { + $self->read_color_table unless %COLORS; + die "unknown color" unless exists $COLORS{lc $_[0]}; + ($r,$g,$b) = @{$COLORS{lc $_[0]}}; + } + return $self->colorResolve($r,$g,$b); +} + +sub transparent { + my $self = shift; + my $index = $self->translate_color(@_); + $self->gd->transparent($index); +} + +=item $index = $img->alphaColor(@args,$alpha) + +Creates an alpha color. You may pass either an (r,g,b) triple or a +symbolic color name, followed by an integer indicating its +opacity. The opacity value ranges from 0 (fully opaque) to 127 (fully +transparent). + +=cut + +sub alphaColor { + my $self = shift; + return unless defined $_[0]; + my ($r,$g,$b,$a); + if (@_ == 4) { # (rgb triplet) + ($r,$g,$b,$a) = @_; + } else { + $self->read_color_table unless %COLORS; + die "unknown color" unless exists $COLORS{lc $_[0]}; + ($r,$g,$b) = @{$COLORS{lc $_[0]}}; + $a = $_[1]; + } + return $self->colorAllocateAlpha($r,$g,$b,$a); +} + +=item @names = GD::Simple->color_names + +=item $translate_table = GD::Simple->color_names + +Called in a list context, color_names() returns the list of symbolic +color names recognized by this module. Called in a scalar context, +the method returns a hash reference in which the keys are the color +names and the values are array references containing [r,g,b] triples. + +=cut + +sub color_names { + my $self = shift; + $self->read_color_table unless %COLORS; + return wantarray ? sort keys %COLORS : \%COLORS; +} + +=item $gd = $img->gd + +Return the internal GD::Image object. Usually you will not need to +call this since all GD methods are automatically referred to this object. + +=cut + +sub gd { shift->{gd} } + +sub read_color_table { + my $class = shift; + while (<DATA>) { + chomp; + last if /^__END__/; + my ($name,$r,$g,$b) = split /\s+/; + $COLORS{$name} = [hex $r,hex $g,hex $b]; + } +} + +sub setBrush { + my $self = shift; + my $brush = shift; + if ($brush->isa('GD::Simple')) { + $self->gd->setBrush($brush->gd); + } else { + $self->gd->setBrush($brush); + } +} + +=item ($red,$green,$blue) = GD::Simple->HSVtoRGB($hue,$saturation,$value) + +Convert a Hue/Saturation/Value (HSV) color into an RGB triple. The +hue, saturation and value are integers from 0 to 255. + +=cut + +sub HSVtoRGB { + my $self = shift; + @_ == 3 or croak "Usage: GD::Simple->HSVtoRGB(\$hue,\$saturation,\$value)"; + + my ($h,$s,$v)=@_; + my ($r,$g,$b,$i,$f,$p,$q,$t); + + if( $s == 0 ) { + ## achromatic (grey) + return ($v,$v,$v); + } + $h %= 255; + $s /= 255; ## scale saturation from 0.0-1.0 + $h /= 255; ## scale hue from 0 to 1.0 + $h *= 360; ## and now scale it to 0 to 360 + + $h /= 60; ## sector 0 to 5 + $i = $h % 6; + $f = $h - $i; ## factorial part of h + $p = $v * ( 1 - $s ); + $q = $v * ( 1 - $s * $f ); + $t = $v * ( 1 - $s * ( 1 - $f ) ); + + if($i<1) { + $r = $v; + $g = $t; + $b = $p; + } elsif($i<2){ + $r = $q; + $g = $v; + $b = $p; + } elsif($i<3){ + $r = $p; + $g = $v; + $b = $t; + } elsif($i<4){ + $r = $p; + $g = $q; + $b = $v; + } elsif($i<5){ + $r = $t; + $g = $p; + $b = $v; + } else { + $r = $v; + $g = $p; + $b = $q; + } + return (int($r+0.5),int($g+0.5),int($b+0.5)); +} + +=item ($hue,$saturation,$value) = GD::Simple->RGBtoHSV($hue,$saturation,$value) + +Convert a Red/Green/Blue (RGB) value into a Hue/Saturation/Value (HSV) +triple. The hue, saturation and value are integers from 0 to 255. + +=back + +=cut + +sub RGBtoHSV { + my $self = shift; + my ($r, $g ,$bl) = @_; + my ($min,undef,$max) = sort {$a<=>$b} ($r,$g,$bl); + return (0,0,0) unless $max > 0; + + my $v = $max; + my $s = 255 * ($max - $min)/$max; + my $h; + my $range = $max - $min; + + if ($range == 0) { # all colors are equal, so monochrome + return (0,0,$max); + } + + if ($max == $r) { + $h = 60 * ($g-$bl)/$range; + } + elsif ($max == $g) { + $h = 60 * ($bl-$r)/$range + 120; + } + else { + $h = 60 * ($r-$g)/$range + 240; + } + + $h = int($h*255/360 + 0.5); + + return ($h, $s, $v); +} + +sub newGroup { + my $self = shift; + return $self->GD::newGroup(@_); +} + +1; + +__DATA__ +white FF FF FF +black 00 00 00 +aliceblue F0 F8 FF +antiquewhite FA EB D7 +aqua 00 FF FF +aquamarine 7F FF D4 +azure F0 FF FF +beige F5 F5 DC +bisque FF E4 C4 +blanchedalmond FF EB CD +blue 00 00 FF +blueviolet 8A 2B E2 +brown A5 2A 2A +burlywood DE B8 87 +cadetblue 5F 9E A0 +chartreuse 7F FF 00 +chocolate D2 69 1E +coral FF 7F 50 +cornflowerblue 64 95 ED +cornsilk FF F8 DC +crimson DC 14 3C +cyan 00 FF FF +darkblue 00 00 8B +darkcyan 00 8B 8B +darkgoldenrod B8 86 0B +darkgray A9 A9 A9 +darkgreen 00 64 00 +darkkhaki BD B7 6B +darkmagenta 8B 00 8B +darkolivegreen 55 6B 2F +darkorange FF 8C 00 +darkorchid 99 32 CC +darkred 8B 00 00 +darksalmon E9 96 7A +darkseagreen 8F BC 8F +darkslateblue 48 3D 8B +darkslategray 2F 4F 4F +darkturquoise 00 CE D1 +darkviolet 94 00 D3 +deeppink FF 14 100 +deepskyblue 00 BF FF +dimgray 69 69 69 +dodgerblue 1E 90 FF +firebrick B2 22 22 +floralwhite FF FA F0 +forestgreen 22 8B 22 +fuchsia FF 00 FF +gainsboro DC DC DC +ghostwhite F8 F8 FF +gold FF D7 00 +goldenrod DA A5 20 +gray 80 80 80 +green 00 80 00 +greenyellow AD FF 2F +honeydew F0 FF F0 +hotpink FF 69 B4 +indianred CD 5C 5C +indigo 4B 00 82 +ivory FF FF F0 +khaki F0 E6 8C +lavender E6 E6 FA +lavenderblush FF F0 F5 +lawngreen 7C FC 00 +lemonchiffon FF FA CD +lightblue AD D8 E6 +lightcoral F0 80 80 +lightcyan E0 FF FF +lightgoldenrodyellow FA FA D2 +lightgreen 90 EE 90 +lightgrey D3 D3 D3 +lightpink FF B6 C1 +lightsalmon FF A0 7A +lightseagreen 20 B2 AA +lightskyblue 87 CE FA +lightslategray 77 88 99 +lightsteelblue B0 C4 DE +lightyellow FF FF E0 +lime 00 FF 00 +limegreen 32 CD 32 +linen FA F0 E6 +magenta FF 00 FF +maroon 80 00 00 +mediumaquamarine 66 CD AA +mediumblue 00 00 CD +mediumorchid BA 55 D3 +mediumpurple 100 70 DB +mediumseagreen 3C B3 71 +mediumslateblue 7B 68 EE +mediumspringgreen 00 FA 9A +mediumturquoise 48 D1 CC +mediumvioletred C7 15 85 +midnightblue 19 19 70 +mintcream F5 FF FA +mistyrose FF E4 E1 +moccasin FF E4 B5 +navajowhite FF DE AD +navy 00 00 80 +oldlace FD F5 E6 +olive 80 80 00 +olivedrab 6B 8E 23 +orange FF A5 00 +orangered FF 45 00 +orchid DA 70 D6 +palegoldenrod EE E8 AA +palegreen 98 FB 98 +paleturquoise AF EE EE +palevioletred DB 70 100 +papayawhip FF EF D5 +peachpuff FF DA B9 +peru CD 85 3F +pink FF C0 CB +plum DD A0 DD +powderblue B0 E0 E6 +purple 80 00 80 +red FF 00 00 +rosybrown BC 8F 8F +royalblue 41 69 E1 +saddlebrown 8B 45 13 +salmon FA 80 72 +sandybrown F4 A4 60 +seagreen 2E 8B 57 +seashell FF F5 EE +sienna A0 52 2D +silver C0 C0 C0 +skyblue 87 CE EB +slateblue 6A 5A CD +slategray 70 80 90 +snow FF FA FA +springgreen 00 FF 7F +steelblue 46 82 B4 +tan D2 B4 8C +teal 00 80 80 +thistle D8 BF D8 +tomato FF 63 47 +turquoise 40 E0 D0 +violet EE 82 EE +wheat F5 DE B3 +whitesmoke F5 F5 F5 +yellow FF FF 00 +yellowgreen 9A CD 32 +gradient1 00 ff 00 +gradient2 0a ff 00 +gradient3 14 ff 00 +gradient4 1e ff 00 +gradient5 28 ff 00 +gradient6 32 ff 00 +gradient7 3d ff 00 +gradient8 47 ff 00 +gradient9 51 ff 00 +gradient10 5b ff 00 +gradient11 65 ff 00 +gradient12 70 ff 00 +gradient13 7a ff 00 +gradient14 84 ff 00 +gradient15 8e ff 00 +gradient16 99 ff 00 +gradient17 a3 ff 00 +gradient18 ad ff 00 +gradient19 b7 ff 00 +gradient20 c1 ff 00 +gradient21 cc ff 00 +gradient22 d6 ff 00 +gradient23 e0 ff 00 +gradient24 ea ff 00 +gradient25 f4 ff 00 +gradient26 ff ff 00 +gradient27 ff f4 00 +gradient28 ff ea 00 +gradient29 ff e0 00 +gradient30 ff d6 00 +gradient31 ff cc 00 +gradient32 ff c1 00 +gradient33 ff b7 00 +gradient34 ff ad 00 +gradient35 ff a3 00 +gradient36 ff 99 00 +gradient37 ff 8e 00 +gradient38 ff 84 00 +gradient39 ff 7a 00 +gradient40 ff 70 00 +gradient41 ff 65 00 +gradient42 ff 5b 00 +gradient43 ff 51 00 +gradient44 ff 47 00 +gradient45 ff 3d 00 +gradient46 ff 32 00 +gradient47 ff 28 00 +gradient48 ff 1e 00 +gradient49 ff 14 00 +gradient50 ff 0a 00 +__END__ + +=head1 COLORS + +This script will create an image showing all the symbolic colors. + + #!/usr/bin/perl + + use strict; + use GD::Simple; + + my @color_names = GD::Simple->color_names; + my $cols = int(sqrt(@color_names)); + my $rows = int(@color_names/$cols)+1; + + my $cell_width = 100; + my $cell_height = 50; + my $legend_height = 16; + my $width = $cols * $cell_width; + my $height = $rows * $cell_height; + + my $img = GD::Simple->new($width,$height); + $img->font(gdSmallFont); + + for (my $c=0; $c<$cols; $c++) { + for (my $r=0; $r<$rows; $r++) { + my $color = $color_names[$c*$rows + $r] or next; + my @topleft = ($c*$cell_width,$r*$cell_height); + my @botright = ($topleft[0]+$cell_width,$topleft[1]+$cell_height-$legend_height); + $img->bgcolor($color); + $img->fgcolor($color); + $img->rectangle(@topleft,@botright); + $img->moveTo($topleft[0]+2,$botright[1]+$legend_height-2); + $img->fgcolor('black'); + $img->string($color); + } + } + + print $img->png; + +=head1 AUTHOR + +The GD::Simple module is copyright 2004, Lincoln D. Stein. It is +distributed under the same terms as Perl itself. See the "Artistic +License" in the Perl source code distribution for licensing terms. + +The latest versions of GD.pm are available at + + http://stein.cshl.org/WWW/software/GD + +=head1 SEE ALSO + +L<GD>, +L<GD::Polyline>, +L<GD::SVG>, +L<Image::Magick> + +=cut