--- loncom/cgi/plot.gif	2001/12/07 22:52:38	1.1
+++ loncom/cgi/plot.gif	2001/12/11 13:47:36	1.3
@@ -1,6 +1,6 @@
 #!/usr/bin/perl 
 #
-# $Id: plot.gif,v 1.1 2001/12/07 22:52:38 matthew Exp $
+# $Id: plot.gif,v 1.3 2001/12/11 13:47:36 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -24,6 +24,8 @@
 #
 # http://www.lon-capa.org/
 #
+###########################################################################
+#
 # CGI-BIN interface to GD, used for making mathematical plots.
 #
 # User specifies the following variables (given are defaults):
@@ -33,6 +35,7 @@
 #    xmax     = " 10.0"
 #    ymin     = "-10.0"
 #    ymax     = " 10.0"
+#    transparent   (doesn't work with gif?)
 #    frame    
 #    drawaxes 
 #    drawtics 
@@ -51,6 +54,7 @@
 #    size of a labelN is one of :
 #       giant, large, medium, small, tiny
 #
+###########################################################################
 use GD;
 
 my @inputs = split(/&/,$ENV{'QUERY_STRING'});
@@ -73,22 +77,27 @@ $axis->{'ylen'} = $axis->{'ymax'} - $axi
 $vtic_every = &grab('vtic_every',1.0,\%In);
 $htic_every = &grab('htic_every',1.0,\%In);
 
-my $image = new GD::Image($height,$width);
+my $image = new GD::Image($width,$height);
 
 # allocate standard colors
-my $white = $image->colorAllocate(255,255,255);
-my $black = $image->colorAllocate(  0,  0,  0);       
-
-# Draw a black frame around the picture
-&drawtics($htic_every,$vtic_every) if (exists($In{"drawtics"}));
-&drawaxes($axis)                   if (exists($In{"drawaxis"}));
-&frame(1)                          if (exists($In{'frame'}));
+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,$y,$black,$size);
+	&drawstring($text,$x,$y,$fgcolor,$size);
 	delete ($In{$_});
 	next;
     } elsif (/^xseries/) {
@@ -101,26 +110,21 @@ foreach (keys %In) {
 	delete ($In{$yname});	
 	if ($#X != $#Y) {
 	    &drawstring("size of $xname and $yname do not match",
-		       10,10,$black,"giant");
+		       10,10,$fgcolor,"giant");
 	    next;
 	}
 	&drawcurve(\@X,\@Y);
     }
 }
 
-# make the background transparent and interlaced
-$image->transparent($white);
-
-# make sure we are writing to a binary stream
-binmode STDOUT;
 
-# Convert the image to PNG and print it on standard output
+# Tell the browser our mime-type
 print <<END;
-Content-type: image/png
+Content-type: image/gif
 
 END
 
-my $BinaryData=$image->plot(\@data)->png;
+my $BinaryData=$image->png;
 undef $image;
 binmode(STDOUT);
 open IMG,"|pngtopnm|ppmtogif 2>/dev/null"; # convert into a gif image
@@ -156,18 +160,18 @@ sub transformPoint{
 sub drawaxes{
     ($x1,$y1) = &transformPoint($axis->{"xmin"},0,$image,$axis);
     ($x2,$y2) = &transformPoint($axis->{"xmax"},0,$image,$axis);
-    $image->line($x1,$y1,$x2,$y2,$black);
+    $image->line($x1,$y1,$x2,$y2,$fgcolor);
     ($x1,$y1) = &transformPoint(0,$axis->{"ymin"},$image,$axis);
     ($x2,$y2) = &transformPoint(0,$axis->{"ymax"},$image,$axis);
-    $image->line($x1,$y1,$x2,$y2,$black);
+    $image->line($x1,$y1,$x2,$y2,$fgcolor);
 }
 
 sub drawtics{
     my ($htic_every,$vtic_every) = @_;
     my ($width,$height) = $image->getBounds();
     
-    $ticwidth  = ($width  > 99 ? 10 : int($width /10) + 1);
-    $ticheight = ($height > 99 ? 10 : int($height/10));
+    $ticwidth  = ($width  > 99 ? 5 : int($width /20) + 1);
+    $ticheight = ($height > 99 ? 5 : int($height/20) + 1);
 
     # Do tics along y-axis
     for ($ntic = 0; $ntic <=int($axis->{"ylen"}/$vtic_every); $ntic++){
@@ -175,7 +179,7 @@ sub drawtics{
 	my ($x2,$y2) = &transformPoint(0,$axis->{"ymin"}+$ntic*$vtic_every);
 	$x1 -= $ticwidth;
 	$x2 += $ticwidth;
-	$image->line($x1,$y1,$x2,$y2,$black);
+	$image->line($x1,$y1,$x2,$y2,$fgcolor);
     }
     # Do tics along x-axis
     for ($ntic = 0; $ntic <=int($axis->{"xlen"}/$htic_every); $ntic++){
@@ -183,7 +187,7 @@ sub drawtics{
 	my ($x2,$y2) = &transformPoint( $axis->{"xmin"}+$ntic*$htic_every,0);
 	$y1 -= $ticheight;
 	$y2 += $ticheight;
-	$image->line($x1,$y1,$x2,$y2,$black);
+	$image->line($x1,$y1,$x2,$y2,$fgcolor);
     }
 }
 
@@ -192,17 +196,17 @@ sub drawcurve{
     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,$y2,$black);
+	$image->line($x1,$y1,$x2,$y2,$fgcolor);
     }
 }
 
-sub frame{
+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-$yoffset,$black);
+    $image->rectangle($xoffset-1,$yoffset-1,$width-$xoffset,$height-$yoffset,$fgcolor);
 }
 
 sub drawstring{