--- loncom/cgi/plot.gif	2001/12/11 13:47:36	1.3
+++ loncom/cgi/plot.gif	2001/12/12 18:36:44	1.4
@@ -1,6 +1,6 @@
-#!/usr/bin/perl 
+#!/usr/bin/perl -w
 #
-# $Id: plot.gif,v 1.3 2001/12/11 13:47:36 matthew Exp $
+# $Id: plot.gif,v 1.4 2001/12/12 18:36:44 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -55,123 +55,170 @@
 #       giant, large, medium, small, tiny
 #
 ###########################################################################
+##
+## Data structures & file description
+## 
+## The input file is taken to be comprised of "segments".  Each "segment"
+## will hold data for the plot header, the coordinate axes, or (more likely)
+## the curves, circles, and polygons that are to be plotted.
+## 
+## The global array @Segments holds references to hashes which contain the
+## data needed for each structure.
+##
+use FileHandle;
 use GD;
 
-my @inputs = split(/&/,$ENV{'QUERY_STRING'});
-foreach $input (@inputs) {
-    ($var,$val) = split /\=/,$input,2;
-    if (! defined($val)) {
-	$val = 1;
-    }
-    $In{lc($var)}=$val;
-}
-
-$height = &grab('height',100,\%In);
-$width  = &grab('width',100,\%In);
-$axis->{'xmin'} = &grab('xmin',-10,\%In);
-$axis->{'xmax'} = &grab('xmax', 10,\%In);
-$axis->{'ymin'} = &grab('ymin',-10,\%In);
-$axis->{'ymax'} = &grab('ymax', 10,\%In);
-$axis->{'xlen'} = $axis->{'xmax'} - $axis->{'xmin'};
-$axis->{'ylen'} = $axis->{'ymax'} - $axis->{'ymin'};
-$vtic_every = &grab('vtic_every',1.0,\%In);
-$htic_every = &grab('htic_every',1.0,\%In);
-
-my $image = new GD::Image($width,$height);
-
-# allocate standard colors
-my @BGvalues = split /,/,&grab('bgcolor','255,255,255',\%In);
-my @FGvalues = split /,/,&grab('fgcolor','0,0,0',\%In);
-my $bgcolor = $image->colorAllocate(@BGvalues);
-my $fgcolor = $image->colorAllocate(@FGvalues);       
-
-# Draw a fgcolor frame around the picture
-&drawtics($htic_every,$vtic_every) if (exists($In{'drawtics'}));
-&drawaxes($axis)                   if (exists($In{'drawaxis'}));
-&drawframe(1)                          if (exists($In{'frame'}));
-# make the background transparent if needed (this doesn't work, at least
-# not for gif images, don't know if it works for png)
-$image->transparent($bgcolor)       if (exists($In{'transparent'}));
-
-## Take care of labels and data series
-foreach (keys %In) {
-    if (/^label/) {
-	my ($x,$y,$size,$text) = split/,/,$In{$_};
-	&drawstring($text,$x,$y,$fgcolor,$size);
-	delete ($In{$_});
-	next;
-    } elsif (/^xseries/) {
-	$xname = $_;
-	$yname = $xname;
-	$yname =~ s/^x/y/;
-	(@X)=split/,/,$In{$xname};
-	(@Y)=split/,/,$In{$yname};
-	delete ($In{$xname});
-	delete ($In{$yname});	
-	if ($#X != $#Y) {
-	    &drawstring("size of $xname and $yname do not match",
-		       10,10,$fgcolor,"giant");
-	    next;
-	}
-	&drawcurve(\@X,\@Y);
-    }
+my ($image,$axis);
+$filename = shift;
+# GET FILENAME AND OPEN THE FILE, BAIL OUT IF UNABLE TO DO SO
+$fh = new FileHandle("<$filename");
+my @Segments = &read_file($fh);
+
+foreach $segment (@Segments) {
+    &set_defaults($segment);
 }
+&init_image(&get_specific_segment(\@Segments,'plotheader'),
+	    &get_specific_segment(\@Segments,'axis'));
 
+for (my $i =0; $i<=$#Segments; $i++) {
+    grok_segment($Segments[$i]);
+}
+&write_image();
 
-# Tell the browser our mime-type
-print <<END;
-Content-type: image/gif
+#---------------------------------------------------- convenience functions
+sub write_image {
+    # Tell the browser our mime-type
+#    print <<END;
+#Content-type: image/gif
+#
+#END
+    my $BinaryData=$image->png;
+    undef $image;
+    binmode(STDOUT);
+    open IMG,"|pngtopnm|ppmtogif 2>/dev/null"; # convert into a gif image
+    print IMG $BinaryData; # output image
+    $|=1;                  # be sure to flush before closing
+    close IMG;
+}
 
-END
+sub grok_segment {
+    $_ = shift;
+    my %Data = %$_;
+    $type = $Data{'type'};
+    if (!defined($type)) { 
+	return undef; 
+    } elsif ($type eq 'frame') {
+	draw_frame(\%Data);
+    } elsif ($type eq 'curve') {
+	draw_curve(\%Data);
+    } elsif ($type eq 'label') {
+	draw_label(\%Data);
+    } elsif ($type eq 'circle') {
+	draw_circle(\%Data);
+    } elsif ($type eq 'polygon') {
+	draw_polygon(\%Data);
+    } elsif ($type eq 'line') {
+	draw_line(\%Data);
+    }
+}
 
-my $BinaryData=$image->png;
-undef $image;
-binmode(STDOUT);
-open IMG,"|pngtopnm|ppmtogif 2>/dev/null"; # convert into a gif image
-print IMG $BinaryData; # output image
-$|=1;                  # be sure to flush before closing
-close IMG;
+sub get_specific_segment {
+    $_ = shift;
+    my @Segments = @$_;
+    my $type = shift;
+    for ($i = 0; $i<=$#Segments; $i++) {
+	if ($Segments[$i]->{'type'} eq $type) {
+	    return (splice @Segments, $i,1);
+	}
+    }
+    return undef;
+}
 
+#---------------------------------------------------- plot description reading
+sub read_file {
+    my @Returned_Segments;
+    my $fh = shift;
+    ($ret,$ref) = read_segment($fh);
+    while (defined($ret) && $ret !=0) {
+	push @Returned_Segments,$ref;
+	($ret,$ref) = read_segment($fh);
+    }
+    return @Returned_Segments;
+}
 
-#--------------------------------------------------------------------
+sub newhash{
+    my %H;
+    return \%H;
+}
 
-sub grab{
-    my ($name,$default,$h) = @_;
-    my $value = $h->{$name};
-    if (defined($value)) {
-	delete ($h->{$name}) ;
-    } else {
-	$value = $default;
+sub read_segment{
+    # Reads in a segment of a plotting file.  
+    # Returns 1,\%Data on success (or parital success)
+    # Returns 0, undef on failure;
+    $fh = shift;
+    my $Data = newhash();
+
+    $_ = <$fh>;
+    if (! /^NEW /) {
+	return undef;
     }
-    return $value;
-}
 
-# transformPoint(x,y) where x,y are in the coordinates of axis will return
-# the coordinates transformed to the image coordinate system.
-sub transformPoint{
-    my ($x,$y) = @_;
-    my ($width,$height) = $image->getBounds();
-    $x = ( $x - $axis->{"xmin"}) * $width / ( $axis->{"xlen"});
-    $y = ( ( $axis->{"ylen"} ) - ($y - $axis->{"ymin"})) 
-	* $height / ( $axis->{"ylen"} );
-    return($x,$y);
+    while($_=<$fh>) {
+	last if (/^END /);
+	# Lines are of the form "type::var=value", "NEW type", or "END type"
+	chomp;
+	return(0,undef) if (/^NEW /);
+	if (/(\w+)::(\w+)[\s]*=\s*\"([\w\s,\-\+\.]+)\"/) {
+	    $Data->{'type'} = $1 if (!exists ($Data->{'type'}));
+	    return(0,$Data) if ($Data->{'type'} ne $1);
+	    $Data->{$2} = $3;
+	} else { 
+	    # Something went wrong - bad input - what to do?
+	}
+    }
+    return (1,$Data);
+}    
+
+#------------------------------------------------------- 
+sub init_image {
+    my $PlotHeader = shift;
+    $axis = shift;
+    # Take care of making the image
+    my ($width,$height) = ($PlotHeader->{'width'},$PlotHeader->{'height'});
+
+    $image = new GD::Image($width,$height);
+    my $bgcolor = $image->colorAllocate(split/,/,$PlotHeader->{'bgcolor'});
+    my $fgcolor = $image->colorAllocate(split/,/,$PlotHeader->{'fgcolor'});
+    $image->transparent($bgcolor) if ($PlotHeader->{'transparent'} eq 'true');
+    
+    $axis->{'xlen'} = $axis->{'xmax'} - $axis->{'xmin'};
+    $axis->{'ylen'} = $axis->{'ymax'} - $axis->{'ymin'};
+    if ($axis->{'drawaxis'} eq 'true') {
+	&draw_axes();
+    }
+    if ($axis->{'drawtics'} eq 'true') {
+	&draw_tics();
+    }
 }
 
-sub drawaxes{
+#-------------------------------------------------------- axis routines
+sub draw_axes{
+    my $color = $image->colorResolve(split /,/,$axis->{'color'});
     ($x1,$y1) = &transformPoint($axis->{"xmin"},0,$image,$axis);
     ($x2,$y2) = &transformPoint($axis->{"xmax"},0,$image,$axis);
-    $image->line($x1,$y1,$x2,$y2,$fgcolor);
+    $image->line($x1,$y1,$x2,$y2,$color);
     ($x1,$y1) = &transformPoint(0,$axis->{"ymin"},$image,$axis);
     ($x2,$y2) = &transformPoint(0,$axis->{"ymax"},$image,$axis);
-    $image->line($x1,$y1,$x2,$y2,$fgcolor);
+    $image->line($x1,$y1,$x2,$y2,$color);
 }
 
-sub drawtics{
-    my ($htic_every,$vtic_every) = @_;
+sub draw_tics{
+    my $color = $image->colorResolve(split /,/, $axis->{'color'});
+    my ($htic_every,$vtic_every) = ($axis->{'htic_every'}, $axis->{'vtic_every'});
     my ($width,$height) = $image->getBounds();
     
-    $ticwidth  = ($width  > 99 ? 5 : int($width /20) + 1);
-    $ticheight = ($height > 99 ? 5 : int($height/20) + 1);
+    my $ticwidth  = ($width  > 99 ? 5 : int($width /20) + 1);
+    my $ticheight = ($height > 99 ? 5 : int($height/20) + 1);
 
     # Do tics along y-axis
     for ($ntic = 0; $ntic <=int($axis->{"ylen"}/$vtic_every); $ntic++){
@@ -179,7 +226,7 @@ sub drawtics{
 	my ($x2,$y2) = &transformPoint(0,$axis->{"ymin"}+$ntic*$vtic_every);
 	$x1 -= $ticwidth;
 	$x2 += $ticwidth;
-	$image->line($x1,$y1,$x2,$y2,$fgcolor);
+	$image->line($x1,$y1,$x2,$y2,$color);
     }
     # Do tics along x-axis
     for ($ntic = 0; $ntic <=int($axis->{"xlen"}/$htic_every); $ntic++){
@@ -187,49 +234,214 @@ sub drawtics{
 	my ($x2,$y2) = &transformPoint( $axis->{"xmin"}+$ntic*$htic_every,0);
 	$y1 -= $ticheight;
 	$y2 += $ticheight;
-	$image->line($x1,$y1,$x2,$y2,$fgcolor);
+	$image->line($x1,$y1,$x2,$y2,$color);
     }
 }
 
-sub drawcurve{
-    my ($X,$Y) = @_;
-    for($i=0;$i< (@$X-1);$i++) {
-	($x1,$y1) = &transformPoint($X->[$i  ],$Y->[$i  ]);
-	($x2,$y2) = &transformPoint($X->[$i+1],$Y->[$i+1]);
-	$image->line($x1,$y1,$x2,$y2,$fgcolor);
+#------------------------------------------------------- misc plotting routines
+sub draw_frame {
+    my $Frame = shift;
+    my ($width,$height) = $image->getBounds();
+    my $color = $image->colorResolve(split /,/,$Frame->{'color'} );
+    # Draw a frame around the picture.
+    my $offset = $Frame->{'offset'};
+    for (my $i = 0; $i<=$Frame->{'thickness'}; $i++) {
+	$image->rectangle(
+			  $offset - 1,
+			  $offset - 1,
+			  $width-$offset,
+			  $height-$offset,
+			  $color);
     }
 }
 
-sub drawframe{
-    # Draw a frame around the picture.
-    my ($xoffset,$yoffset) = @_;
-    $xoffset = $xoffset || 1;
-    $yoffset = $yoffset || $xoffset;
-    my ($width,$height) = $image->getBounds();
-    $image->rectangle($xoffset-1,$yoffset-1,$width-$xoffset,$height-$yoffset,$fgcolor);
+sub draw_line{
+    my $Line = shift;
+    my $color = $image->colorResolve(split/,/, $Line->{'color'});
+    my ($x1,$y1) = &transformPoint($Line->{'x1'},$Line->{'y1'});
+    my ($x2,$y2) = &transformPoint($Line->{'x2'},$Line->{'y2'});
+    $image->line($x1,$y1,$x2,$y2,$color);
+}
+
+sub draw_curve{
+    my $Curve = shift;
+    my $color = $image->colorResolve(split /,/, $Curve->{'color'});
+    @X = split /,/,$Curve->{'xdata'};
+    @Y = split /,/,$Curve->{'ydata'};
+    if ($#X != $#Y) {
+	return 0;
+    }
+    for($i=0;$i< $#X ;$i++) {
+	my ($x1,$y1) = &transformPoint($X[$i]  ,$Y[$i]);
+	my ($x2,$y2) = &transformPoint($X[$i+1],$Y[$i+1]);
+	$image->line($x1,$y1,$x2,$y2,$color);
+    }
 }
 
-sub drawstring{
-    # Write some text on the image.
-    my ($text,$x,$y,$color,$fontName) = @_;
-    $font = gdGiantFont      if (lc($fontName) eq "giant" ||
-				 lc($fontName) eq "huge"     );
-    $font = gdLargeFont      if (lc($fontName) eq "large");
-    $font = gdMediumBoldFont if (lc($fontName) eq "medium");
-    $font = gdSmallFont      if (lc($fontName) eq "small");
-    $font = gdTinyFont       if (lc($fontName) eq "tiny");
+sub draw_label{
+    my $Label = shift;
+    my $color = $image->colorResolve(split /,/, $Label->{'color'});
+    my $fontname = $Label->{'font'};
+    my $font = gdGiantFont      if (lc($fontname) eq "giant" ||
+				 lc($fontname) eq "huge"  );
+    $font = gdLargeFont      if (lc($fontname) eq "large" );
+    $font = gdMediumBoldFont if (lc($fontname) eq "medium");
+    $font = gdSmallFont      if (lc($fontname) eq "small" );
+    $font = gdTinyFont       if (lc($fontname) eq "tiny"  );
+    my $text = $Label->{'text'};
     if (! defined($font)) {
 	$font = gdGiantFont;
 	$text = "Font size error!";
     }
-    ($x,$y) = &transformPoint($x,$y);
+    my ($x,$y) = &transformPoint($Label->{'x'},$Label->{'y'});
     $image->string($font,$x,$y,$text,$color);
 }
 
+sub draw_circle {
+    my $Circle = shift;
+    my ($width,$height) = $image->getBounds();
+    my $color = $image->colorResolve(split /,/, $Circle->{'color'});
+    my ($x,$y) = &transformPoint(split/,/,$Circle->{'center'});
+    my $xradius = $Circle->{'radius'} * $width  / $axis->{'xlen'};
+    my $yradius = $Circle->{'radius'} * $height / $axis->{'ylen'};
+    # draw a semicircle centered at 100,100
+    $image->arc($x,$y,$xradius,$yradius,0,360,$color);
+    $image->fill($x,$y,$color) if ($Circle->{'filled'} eq 'true');
+}
 
+sub draw_polygon {
+    my $Poly = shift;
+    my $color = $image->colorResolve(split /,/, $Poly->{'color'});
+    @X = split /,/,$Poly->{'xdata'};
+    @Y = split /,/,$Poly->{'ydata'};
+    if ($#X != $#Y) {
+	return 0;
+    }
+    my $poly = new GD::Polygon;
+    for ($i=0;$i<=$#X;$i++) {
+	$poly->addPt(&transformPoint($X[$i],$Y[$i]));
+    }
+    if ($Poly->{'filled'} eq 'true') {
+	$image->filledPolygon($poly,$color);
+    } else {
+	$image->polygon($poly,$color);
+    }
+}
 
+#------------------------------------------ transform point (basic routine)
+#
+# transformPoint(x,y) where x,y are in the coordinates of axis will return
+# the coordinates transformed to the image coordinate system.
+sub transformPoint{
+    my ($x,$y) = @_;
+    my ($width,$height) = $image->getBounds();
+    $x = ( $x - $axis->{"xmin"}) * $width / ( $axis->{"xlen"});
+    $y = ( ( $axis->{"ylen"} ) - ($y - $axis->{"ymin"})) 
+	* $height / ( $axis->{"ylen"} );
+    return($x,$y);
+}
 
+#------------------------------------------ set defaults is a beast!
 
-
+sub set_defaults {
+    my $PlotHeader = { 	
+	type        => "plotheader",
+	name        => "plot",
+	height      => "200",
+	width       => "300", 
+	bgcolor     => "255,255,255",
+	fgcolor     => "  0,  0,  0", 
+	transparent => "true"
+	};
+
+    my $Axis = {
+	type       => "axis",
+	name       => "axis",
+	color      => "  0,  0,  0",
+	drawtics   => "true",
+	vtic_every => " 1.0",
+	htic_every => " 1.0",
+	xmin       => "-10.0",
+	ymin       => " -5.0",
+	xmax       => " 10.0",
+	ymax       => "  5.0",
+	drawaxis   => "true"
+	};
+
+    my $Frame = {
+	type      => "frame",
+	color     => "  0,  0,  0",
+	offset    => "1.0",
+	thickness => "1.0",
+	drawframe => "true"
+	};
+
+    my $Curve= {
+	type  => "curve",
+	name  => "curve",
+	color => "  0,  0,  0",
+	xdata => " 1.0, 2.0, 3.0, 4.0, 5.0, 6.0",
+	ydata => " 1.0, 2.0, 3.0, 4.0, 5.0, 6.0"
+	};
+
+    my $Label = {
+	type  => "label",
+	name  => "label",
+	font  => "medium",
+	text  => "default label text",
+	color => "  0,  0,  0",
+	x     => " -5.0",
+	y     => "  5.0"
+	};	
+
+    my $Circle = {
+	type      => "circle",
+	name      => "circle",
+	color     => "  0,  0,  0",
+	filled    => "true",
+	center    => "x,y",
+	radius    => "12.0"
+	};
+    
+    my $Polygon = {
+	type      => "polygon",
+	name      => "polygon",
+	color     => "  0,  0,  0",
+	filled    => "true",
+	xdata     => "1.0, 0.5, 0.0, -0,5, -1.0, -0.5,  0.0,  0.5",
+	ydata     => "0.0,-0.5,-1.0, -0.5,  0.0,  0.5,  1.0,  0.5"
+	};    
+
+    my $Line = { 
+	type      => "line",
+	name      => "line",
+	color     => "  0,  0,  0",
+	x1        => "1.0",
+	y1        => "0.0",
+	x2        => "2.0",
+	y2        => "4.0"
+	};
+
+    my $typematch = {
+	plotheader => $PlotHeader,
+	axis       => $Axis,
+	frame      => $Frame,
+	label      => $Label,
+	curve      => $Curve,
+	circle     => $Circle,
+	polygon    => $Polygon
+	};
+
+    my $seg = shift;
+    if (exists($typematch->{$seg->{'type'}})) {
+	my $H = $typematch->{$seg->{'type'}};
+	foreach $key (keys %$H) {
+	    if (! exists($seg->{$key})) {
+		$seg->{$key} = $H->{$key};
+	    }
+	}
+    }
+}
+