--- loncom/xml/lonplot.pm	2012/07/03 11:29:57	1.156
+++ loncom/xml/lonplot.pm	2012/09/10 09:51:15	1.166
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Dynamic plot
 #
-# $Id: lonplot.pm,v 1.156 2012/07/03 11:29:57 foxr Exp $
+# $Id: lonplot.pm,v 1.166 2012/09/10 09:51:15 foxr Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -98,11 +98,16 @@ BEGIN {
 my $max_str_len = 50;    # if a label, title, xlabel, or ylabel text
                          # is longer than this, it will be truncated.
 
-my %linetypes =
+my %linetypes =			# For png use these linetypes.
     (
      solid          => 1,
      dashed         => 0
     );
+my %ps_linetypes = 		# For ps the line types are different!
+   (
+    solid          => 0,
+    dashed         => 7
+   );
 
 my %linestyles = 
     (
@@ -134,6 +139,10 @@ my $sml_test       = sub {$_[0]=~/^(\d+|
 my $linestyle_test = sub {exists($linestyles{$_[0]})};
 my $words_test     = sub {$_[0]=~s/\s+/ /g;$_[0]=~/^([\w~!\@\#\$\%^&\*\(\)-=_\+\[\]\{\}:\;\'<>,\.\/\?\\]+ ?)+$/};
 
+my $arrowhead_test = sub{$_[0]=~/^(nohead|head|heads| )+$/};
+my $arrowstyle_test= sub{$_[0]=~/^(filled|empty|nofilled)+$/};
+my $degree_test  = sub{&$pos_real_test($_[0]) && ($_[0] <= 360.0)};
+
 ###################################################################
 ##                                                               ##
 ##                      Attribute metadata                       ##
@@ -454,7 +463,13 @@ my %tic_defaults =
 	 description => 'Number of minor tics per major tic mark',
 	 edit_type   => 'entry',
 	 size        => '10'
-	 },         
+	 }, 
+     rotate => {
+	 default => 'off',
+	 test    => $onoff_test,
+	 description => 'Rotate tic label by 90 degrees if on',
+	 edit_type   => 'onoff'
+     }
      );
 
 my @axis_edit_order = ('color','xmin','xmax','ymin','ymax','xformat', 'yformat', 'xzero', 'yzero');
@@ -528,7 +543,11 @@ my %axis_defaults =
      	},
      );
 
-my @curve_edit_order = ('color','name','linestyle','linewidth','linetype','pointtype','pointsize','limit');
+
+my @curve_edit_order = ('color','name','linestyle','linewidth','linetype',
+			'pointtype','pointsize','limit', 'arrowhead', 'arrowstyle', 
+			'arrowlength', 'arrowangle', 'arrowbackangle'
+    );
 
 my %curve_defaults = 
     (
@@ -589,6 +608,43 @@ my %curve_defaults =
          edit_type   => 'choice',
          choices     => ['above', 'below', 'closed','x1','x2','y1','y2']
          },
+     arrowhead => {
+         default     => 'head',
+	 test        => $arrowhead_test,
+	 description => 'Vector arrow head type',
+	 edit_type   => 'choice',
+	 choices     => ['nohead', 'head', 'heads']
+     },
+     arrowstyle => {
+	 default     => 'filled',
+	 test        => $arrowstyle_test,
+	 description => 'Vector arrow head style',
+	 edit_type   => 'choice',
+	 choices     => ['filled', 'empty', 'nofilled']
+     },
+     arrowlength => {
+	 default     => 0.02,
+	 test        => $pos_real_test,
+	 description => "Length of vector arrow (only applies to vector plots)",
+	 edit_type   => 'entry',
+	 size        => '5'
+     },
+     arrowangle  => {
+	default      => 10.0,
+	test         => $degree_test,
+	description  => 'Angle of arrow branches to arrow body (only applies to vector plots)',
+	edit_type    => 'entry',
+	size         => '5'
+     },
+
+     arrowbackangle => {
+	 default    => 90.0,
+	 test       => $degree_test,
+	 descripton => 'Angle of arrow back lines to branches.',
+	 edit_type  => 'entry',
+	 size       => '5'
+     }
+
      );
 
 ###################################################################
@@ -600,6 +656,8 @@ my %curve_defaults =
 undef %Apache::lonplot::plot;
 my (%key,%axis,$title,$xlabel,$ylabel,@labels,@curves,%xtics,%ytics);
 
+my $current_tics;		# Reference to the current tick hash
+
 sub start_gnuplot {
     undef(%Apache::lonplot::plot);   undef(%key);    undef(%axis);
     undef($title);  undef($xlabel); undef($ylabel);
@@ -699,6 +757,8 @@ sub start_xtics {
     if ($target eq 'web' || $target eq 'tex') {
 	&get_attributes(\%xtics,\%tic_defaults,$parstack,$safeeval,
 		    $tagstack->[-1]);
+	$current_tics = \%xtics;
+	&Apache::lonxml::register('Apache::lonplot', 'tic');
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'xtics');
 	$result .= &edit_attributes($target,$token,\%tic_defaults,
@@ -717,6 +777,7 @@ sub end_xtics {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web' || $target eq 'tex') {
+	&Apache::lonxml::deregister('Apache::lonplot', 'tic');
     } elsif ($target eq 'edit') {
 	$result.=&Apache::edit::tag_end($target,$token);
     }
@@ -730,6 +791,8 @@ sub start_ytics {
     if ($target eq 'web' || $target eq 'tex') {
 	&get_attributes(\%ytics,\%tic_defaults,$parstack,$safeeval,
 		    $tagstack->[-1]);
+	$current_tics = \%ytics;
+	&Apache::lonxml::register('Apache::lonplot', 'tic');
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'ytics');
 	$result .= &edit_attributes($target,$token,\%tic_defaults,
@@ -748,12 +811,55 @@ sub end_ytics {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web' || $target eq 'tex') {
+	&Apache::lonxml::deregister('Apache::lonplot', 'tic');
     } elsif ($target eq 'edit') {
 	$result.=&Apache::edit::tag_end($target,$token);
     }
     return $result;
 }
 
+
+##----------------------------------------------------------------
+#
+#  Tic handling:
+#   The <tic> tag allows users to specify exact Tic positions and labels
+#   for each axis.  In this version we only support level 0 tics (major tic).
+#   Each tic has associated with it a position and a label
+#   $current_tics is a reference to the current tick description hash.
+#   We add elements to an array  in that has: ticspecs whose elements
+#   are 'pos' - the tick position and 'label' - the tic label.
+#
+
+
+sub start_tic {
+    my ($target, $token, $tagstack, $parstack, $parser, $safeeval, $style)  = @_;
+
+    my $result = '';
+    if ($target eq 'web' || $target eq 'tex') {
+	my $tic_location = &Apache::lonxml::get_param('location', $parstack, $safeeval);
+	my $tic_label    = &Apache::lonxml::get_all_text('/tic', $parser);
+
+	# Tic location must e a real:
+
+	if (!&$real_test($tic_location)) {
+	    &Apache::lonxml::warning("Tic location: $tic_location must be a real number");
+	} else {
+
+	    if (!defined  $current_tics->{'ticspecs'}) {
+		$current_tics->{'ticspecs'} = [];
+	    }
+	    my $ticspecs = $current_tics->{'ticspecs'};
+	    push (@$ticspecs, {'pos' => $tic_location, 'label' => $tic_label});
+	}
+    }
+
+    return $result;
+}
+
+sub end_tic {
+    return '';
+}
+
 ##-----------------------------------------------------------------font
 my %font_properties =
     (
@@ -1408,6 +1514,8 @@ sub start_function {
 						     $style);
 	$function = &Apache::run::evaluate($function,$safeeval,$$parstack[-1]);
         $function=~s/\^/\*\*/gs;
+	$function=~ s/^\s+//;	# Trim leading
+	$function=~ s/\s+$//;   # And trailing whitespace.
 	$curves[-1]->{'function'} = $function; 
     } elsif ($target eq 'edit') {
 	$result .= &Apache::edit::tag_start($target,$token,'Gnuplot compatible curve function');
@@ -1587,11 +1695,71 @@ sub get_attributes{
     }
     return ;
 }
+##
+# Generate tic mark specifications.
+# 
+# @param type - type of tics (xtics or ytics).
+# @param spec - Reference to a hash that contains the tic specification.
+# @param target - 'tex' if hard copy target.
+#
+# @return string - the tic specification command.
+#
+sub generate_tics {
+    my ($type, $spec, $target) = @_;
+    my $result   = '';
+
+
+    if (defined %$spec) {
+
+	
+
+	# Major tics: - If there are 'ticspecs' these override any other
+	#               specifications:
+
+	
+	
+	$result .= "set $type $spec->{'location'}  ";
+	$result .= ($spec->{'mirror'} eq 'on') ? 'mirror ' : 'nomirror ';
+	if ($spec->{'rotate'} eq 'on') {
+	    $result .= ' rotate ';
+	}
+	if (defined $spec->{'ticspecs'}) {
+	    $result .= '( ';
+	    my @ticspecs;
+	    my $ticinfo = $spec->{'ticspecs'};
+	    foreach my $tic (@$ticinfo) {
+		push(@ticspecs,  '"' . $tic->{'label'} . '" ' . $tic->{'pos'} );
+	    }
+	    $result .= join(', ', (@ticspecs));
+	    $result .= ' )';
+	} else {
+	    $result .= "$spec->{'start'}, ";
+	    $result .= "$spec->{'increment'}, ";
+	    $result .= "$spec->{'end'} ";
+	}
+	if ($target eq 'tex' ) {
+	    $result .= 'font "Helvetica,22"';
+	}
+	$result .= "\n";
+	
+	# minor frequency:
+	
+	if ($spec->{'minorfreq'} != 0) {
+	    $result .= "set m$type $spec->{'minorfreq'}\n";
+	}
+    } else {
+	$result .= "set $type font " . '"Helvetica,22"' ."\n";
+    }
+    
+    
+    return $result;
+}
 
 ##------------------------------------------------------- write_gnuplot_file
 sub write_gnuplot_file {
     my ($tmpdir,$filename,$target)= @_;
     my ($fontsize, $font_properties) =  &get_font($target);
+    &Apache::lonnet::logthis("Fontsize: $fontsize");
     my $gnuplot_input = '';
     my $curve;
     #
@@ -1648,6 +1816,7 @@ sub write_gnuplot_file {
 	$gnuplot_input .= "set encoding iso_8859_1\n"; # Get access to extended font.
 
     }
+    $gnuplot_input .= "set encoding utf8\n";
     # cartesian or polar plot?
     if (lc($Apache::lonplot::plot{'plottype'}) eq 'polar') {
         $gnuplot_input .= 'set polar'.$/;
@@ -1728,42 +1897,10 @@ sub write_gnuplot_file {
         $gnuplot_input .= "set ylabel \"$ylabel\" $extra_space_y \n" if (defined($ylabel));
     }
     # tics
-    if (%xtics) {    
-	$gnuplot_input .= "set xtics $xtics{'location'} ";
-	$gnuplot_input .= ( $xtics{'mirror'} eq 'on'?"mirror ":"nomirror ");
-	$gnuplot_input .= "$xtics{'start'}, ";
-	$gnuplot_input .= "$xtics{'increment'}, ";
-	$gnuplot_input .= "$xtics{'end'} ";
-	if ($target eq 'tex') {
-	    $gnuplot_input .= 'font "Helvetica,22"';     # Needed in iso 8859-1 enc.
-	}
-	$gnuplot_input .= "\n";
-        if ($xtics{'minorfreq'} != 0) {
-            $gnuplot_input .= "set mxtics ".$xtics{'minorfreq'}."\n";
-        } 
-    } else {
-	if ($target eq 'tex') {
-	    $gnuplot_input .= 'set xtics font "Helvetica,22"'."\n"; # needed in iso 8859-1 enc
-	}
-    }
-    if (%ytics) {    
-	$gnuplot_input .= "set ytics $ytics{'location'} ";
-	$gnuplot_input .= ( $ytics{'mirror'} eq 'on'?"mirror ":"nomirror ");
-	$gnuplot_input .= "$ytics{'start'}, ";
-	$gnuplot_input .= "$ytics{'increment'}, ";
-        $gnuplot_input .= "$ytics{'end'} ";
-        if ($target eq 'tex') {
-            $gnuplot_input .= 'font "Helvetica,22"'; # Needed in iso-8859-1 encoding.
-        }
-        $gnuplot_input .= "\n";
-        if ($ytics{'minorfreq'} != 0) {
-            $gnuplot_input .= "set mytics ".$ytics{'minorfreq'}."\n";
-        } 
-    } else {
-	if ($target eq 'tex') {
-	    $gnuplot_input .= 'set ytics font "Helvetica,22"'."\n"; # Needed for iso 8859-1 enc.
-	}
-    }
+    $gnuplot_input .= &generate_tics('xtics', \%xtics, $target);
+
+    $gnuplot_input .= &generate_tics('ytics', \%ytics, $target);
+
     # axis
     if (%axis) {
         if ($axis{'xformat'} ne 'on') {
@@ -1842,10 +1979,13 @@ sub write_gnuplot_file {
     #  type (solid/dashed), color, width
     #
     my $linestyle_index = 50;
-    my $line_type    = '';     
-    my $line_color   = '';
     my $line_width   = '';
 
+    # If arrows are needed there will be an arrow style for each as well:
+    #
+
+    my $arrow_style_index = 50;
+
     my $plot_command;
     my $plot_type;
 
@@ -1855,6 +1995,7 @@ sub write_gnuplot_file {
 	if ($target eq 'tex') {
 	    $curve->{'linewidth'} *= 2;
 	}
+	$line_width = $curve->{'linewidth'};
 	if (exists($curve->{'function'})) {
 	    $plot_type    = 
 		$curve->{'function'}.' title "'.
@@ -1884,31 +2025,76 @@ sub write_gnuplot_file {
 		$curve->{'name'}.'" with '.
 		$curve->{'linestyle'};
 	}
+	my $pointtype = '';
+	my $pointsize = '';
+
+	# Figure out the linestyle:
+
+	my $lt = $curve->{'linetype'} ne '' ? $curve->{'linetype'} 
+	                : 'solid';	# Line type defaults to solid.
+	# The mapping of lt -> the actual gnuplot line type depends on the target:
+
+	if ($target eq 'tex') {
+	    $lt = $ps_linetypes{$lt};
+	} else {
+	    $lt = $linetypes{$lt}
+	}
+
+	my $color = $curve->{'color'};
+	$color =~ s/^x/#/;	        # Convert xhex color -> #hex color.   
+
+	my $style_command = "set style line $linestyle_index $pointtype $pointsize linetype $lt linewidth $line_width lc rgb '$color'\n";
+	$gnuplot_input .= $style_command;
+
+
+
 	if (($curve->{'linestyle'} eq 'points')      ||
 	    ($curve->{'linestyle'} eq 'linespoints') ||
 	    ($curve->{'linestyle'} eq 'errorbars')   ||
 	    ($curve->{'linestyle'} eq 'xerrorbars')  ||
 	    ($curve->{'linestyle'} eq 'yerrorbars')  ||
 	    ($curve->{'linestyle'} eq 'xyerrorbars')) {
-	    $plot_command.=' pointtype '.$curve->{'pointtype'};
-	    $plot_command.=' pointsize '.$curve->{'pointsize'};
+	    
+	    $pointtype =' pointtype '.$curve->{'pointtype'};
+	    $pointsize =' pointsize '.$curve->{'pointsize'};
 	} elsif ($curve->{'linestyle'} eq 'filledcurves') { 
 	    $plot_command.= ' '.$curve->{'limit'};
-	} elsif ($curve->{'linetype'} ne '' &&
-		 $curve->{'linestyle'} eq 'lines') {
-	    $plot_command.= ' linetype ';
-	    $plot_command.= $linetypes{$curve->{'linetype'}};
-	    $plot_command.= ' linecolor rgb "';
-	    # convert color from xaaaaaa to #aaaaaa
-	    $curve->{'color'} =~ s/^x/#/;
-	    $plot_command.= $curve->{'color'}.'"';
+	} elsif ($curve->{'linestyle'} eq 'vector') {
+
+	    # Create the arrow head style add it to 
+	    # $gnuplot_input..and ensure it gets
+	    # Selected in the plot command.
+
+	    $gnuplot_input .= "set style arrow $arrow_style_index ";
+	    $gnuplot_input .= ' ' . $curve->{'arrowhead'};
+	    $gnuplot_input .= ' size ' . $curve->{'arrowlength'};
+	    $gnuplot_input .= ','.$curve->{'arrowangle'};
+	    $gnuplot_input .= ',' . $curve->{'arrowbackangle'}; 
+	    $gnuplot_input .=  ' ' . $curve->{'arrowstyle'} . " ls $linestyle_index\n";
+
+
+	    $plot_command  .= "  arrowstyle $arrow_style_index ";
+	    $arrow_style_index++;
 	}
-	$plot_command.= ' linewidth '.$curve->{'linewidth'};
+
+
+
+
+	# The condition below is because gnuplot lumps the linestyle in with the 
+	# arrowstyle _sigh_.
+
+	if ($curve->{'linestyle'} ne 'vector') {
+	    $plot_command.= " ls $linestyle_index";
+	}
+
 	$gnuplot_input .= 'plot ' . $plot_type . ' ' . $plot_command . "\n";
+	$linestyle_index++;	# Each curve get a unique linestyle.
     }
     # Write the output to a file.
-    open (my $fh,">$tmpdir$filename.data");
-    binmode($fh, ":utf8");
+
+    # &Apache::lonnet::logthis($gnuplot_input); # uncomment to log the gnuplot input.
+    open (my $fh, "> $tmpdir$filename.data");
+    binmode($fh, ':utf8');
     print $fh $gnuplot_input;
     close($fh);
     # That's all folks.