--- loncom/homework/functionplotresponse.pm	2010/11/19 17:20:44	1.40
+++ loncom/homework/functionplotresponse.pm	2010/11/19 20:03:13	1.41
@@ -1,7 +1,7 @@
 # LearningOnline Network with CAPA
 # option list style responses
 #
-# $Id: functionplotresponse.pm,v 1.40 2010/11/19 17:20:44 www Exp $
+# $Id: functionplotresponse.pm,v 1.41 2010/11/19 20:03:13 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -316,17 +316,21 @@ ENDYAXISLABELSCRIPT
 }
 
 sub plot_script {
-   my ($id,$function,$fixed)=@_;
+   my ($id,$function,$fixed,$label,$xmin,$xmax)=@_;
+   $label=~s/\W//g;
+   if (($label) && ($label!~/^[A-Za-z]/)) {
+      $label='C'.$label;
+   }
+   my $visible=0;
+   if ($label) {
+      $visible="1";
+   } else {
+      $Apache::functionplotresponse::counter++;
+      $label='C'.$Apache::functionplotresponse::counter;
+   }
    if ($fixed) {
-# Use stupid trick to nail this to a location
-# Oddly, it seems like only one plot cannot be nailed to a location
-# Non-nailed-down plots apparently get overwritten
-      return (<<ENDPLOTSCRIPT);
-            document.ggbApplet_$id.evalCommand("a=1");
-            document.ggbApplet_$id.setVisible("a",false);
-            // This MUST be a DEPENDENT OBJECT in order to be locked down:
-            document.ggbApplet_$id.evalCommand("y=a*($function)");
-ENDPLOTSCRIPT
+      return "document.ggbApplet_$id.evalCommand('$label=Function[$function,$xmin,$xmax]')".
+             ($visible?'':"document.ggbApplet.setLabelVisible('$label', false);");
    } else {
        return "document.ggbApplet_$id.evalCommand('y=$function')";
    }
@@ -365,21 +369,25 @@ sub start_backgroundplot {
    my $result='';
    my $internalid = $Apache::inputtags::part.'_'.$Apache::inputtags::response[-1];
    my $function=&Apache::lonxml::get_param('function',$parstack,$safeeval);
+   my $label=&Apache::lonxml::get_param('label',$parstack,$safeeval);
    my $fixed=(&Apache::lonxml::get_param('fixed',$parstack,$safeeval)=~/on|true|yes|1/i?1:0);
  
    unless ($function) { $function="0"; }
    if ($target eq 'web') {
-      $result.=&plot_script($internalid,$function,$fixed);
+      my ($xmin,$xmax,$ymin,$ymax)=&boundaries($parstack,$safeeval,-3);
+      $result.=&plot_script($internalid,$function,$fixed,$label,$xmin,$xmax);
    } elsif ($target eq 'edit') {
         $result=&Apache::edit::tag_start($target,$token,'Background Function Plot').
              &Apache::edit::text_arg('Function:','function',
                                      $token,'16').
+             &Apache::edit::text_arg('Label on Plot:','label',
+                                     $token,'8').
              &Apache::edit::select_arg('Fixed location:','fixed',
                                   ['yes','no'],$token).
              &Apache::edit::end_row();
   } elsif ($target eq 'modified') {
     my $constructtag=&Apache::edit::get_new_args($token,$parstack,
-                                                 $safeeval,'function','fixed');
+                                                 $safeeval,'function','label','fixed');
     if ($constructtag) { $result=&Apache::edit::rebuild_tag($token); }
   }
   return $result;
@@ -753,22 +761,7 @@ sub start_functionplotresponse {
   &decode_previous_answer($Apache::lonhomework::history{"resource.$partid.$id.submission"});
 
 # Parameters of <functionplotresponse>
-  my $xmin=&Apache::lonxml::get_param('xmin',$parstack,$safeeval);
-  $xmin=(defined($xmin)?$xmin:-10);
-  my $xmax=&Apache::lonxml::get_param('xmax',$parstack,$safeeval);
-  $xmax=(defined($xmax)?$xmax:10);
-  my $ymin=&Apache::lonxml::get_param('ymin',$parstack,$safeeval);
-  $ymin=(defined($ymin)?$ymin:-10);
-  my $ymax=&Apache::lonxml::get_param('ymax',$parstack,$safeeval);
-  $ymax=(defined($ymax)?$ymax:10);
-  if ($xmax<=$xmin) {
-     &Apache::lonxml::warning('Maximum x-value needs to be larger than minimum value.');
-     $xmax=$xmin+20;
-  }
-  if ($ymax<=$ymin) {
-     &Apache::lonxml::warning('Maximum y-value needs to be larger than minimum value.');
-     $ymax=$ymin+20;
-  }
+  my ($xmin,$xmax,$ymin,$ymax)=&boundaries($parstack,$safeeval);
   my $xaxisvisible=(&Apache::lonxml::get_param('xaxisvisible',$parstack,$safeeval)=~/on|true|yes|1/i?'true':'false');
   my $yaxisvisible=(&Apache::lonxml::get_param('yaxisvisible',$parstack,$safeeval)=~/on|true|yes|1/i?'true':'false');
   my $gridvisible=(&Apache::lonxml::get_param('gridvisible',$parstack,$safeeval)=~/on|true|yes|1/i?'true':'false');
@@ -1035,14 +1028,7 @@ sub end_functionplotruleset {
 #
 # Actually grade
 #
-        my $xmin=&Apache::lonxml::get_param('xmin',$parstack,$safeeval,-2);
-        $xmin=(defined($xmin)?$xmin:-10);
-        my $xmax=&Apache::lonxml::get_param('xmax',$parstack,$safeeval,-2);
-        $xmax=(defined($xmax)?$xmax:10);
-        my $ymin=&Apache::lonxml::get_param('ymin',$parstack,$safeeval,-2);
-        $ymin=(defined($ymin)?$ymin:-10);
-        my $ymax=&Apache::lonxml::get_param('ymax',$parstack,$safeeval,-2);
-        $ymax=(defined($ymax)?$ymax:10);
+    my ($xmin,$xmax,$ymin,$ymax)=&boundaries($parstack,$safeeval,-2);
 
         my $ad='';
         undef  %Apache::functionplotresponse::functionplotrulelabels;
@@ -1122,20 +1108,7 @@ sub end_functionplotelements {
      $result=&Apache::edit::end_table();
   } elsif ($target eq 'web') {
 # Now is the time to render all of the stored splines
-      my $xmin=&Apache::lonxml::get_param('xmin',$parstack,$safeeval,-2);
-      $xmin=(defined($xmin)?$xmin:-10);
-      my $xmax=&Apache::lonxml::get_param('xmax',$parstack,$safeeval,-2);
-      $xmax=(defined($xmax)?$xmax:10);
-      my $ymin=&Apache::lonxml::get_param('ymin',$parstack,$safeeval,-2);
-      $ymin=(defined($ymin)?$ymin:-10);
-      my $ymax=&Apache::lonxml::get_param('ymax',$parstack,$safeeval,-2);
-      $ymax=(defined($ymax)?$ymax:10);
-      if ($xmax<=$xmin) {
-        $xmax=$xmin+20;
-      }
-      if ($ymax<=$ymin) {
-         $ymax=$ymin+20;
-      }
+     my ($xmin,$xmax,$ymin,$ymax)=&boundaries($parstack,$safeeval,-2);
      foreach my $label (keys(%Apache::functionplotresponse::splineorder)) {
         $result.=&generate_spline($internalid,$label,$xmin,$xmax,$ymin,$ymax);
      }
@@ -1162,6 +1135,25 @@ sub end_functionplotelements {
   return $result;
 }
 
+sub boundaries {
+   my ($parstack,$safeeval,$level)=@_;
+   my $xmin=&Apache::lonxml::get_param('xmin',$parstack,$safeeval,$level);
+   $xmin=(defined($xmin)?$xmin:-10);
+   my $xmax=&Apache::lonxml::get_param('xmax',$parstack,$safeeval,$level);
+   $xmax=(defined($xmax)?$xmax:10);
+   my $ymin=&Apache::lonxml::get_param('ymin',$parstack,$safeeval,$level);
+   $ymin=(defined($ymin)?$ymin:-10);
+   my $ymax=&Apache::lonxml::get_param('ymax',$parstack,$safeeval,$level);
+   $ymax=(defined($ymax)?$ymax:10);
+   if ($xmax<=$xmin) {
+      $xmax=$xmin+20;
+   }
+   if ($ymax<=$ymin) {
+      $ymax=$ymin+20;
+   }
+   return ($xmin,$xmax,$ymin,$ymax);
+}
+
 sub start_functionplotelements {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
@@ -1181,20 +1173,7 @@ sub start_functionplotelements {
        .&Apache::edit::start_spanning_row()
        ."\n";
    } elsif ($target eq 'web') {
-      my $xmin=&Apache::lonxml::get_param('xmin',$parstack,$safeeval,-2);
-      $xmin=(defined($xmin)?$xmin:-10);
-      my $xmax=&Apache::lonxml::get_param('xmax',$parstack,$safeeval,-2);
-      $xmax=(defined($xmax)?$xmax:10);
-      my $ymin=&Apache::lonxml::get_param('ymin',$parstack,$safeeval,-2);
-      $ymin=(defined($ymin)?$ymin:-10);
-      my $ymax=&Apache::lonxml::get_param('ymax',$parstack,$safeeval,-2);
-      $ymax=(defined($ymax)?$ymax:10);
-      if ($xmax<=$xmin) {
-        $xmax=$xmin+20;
-      }
-      if ($ymax<=$ymin) {
-         $ymax=$ymin+20;
-      }
+      my ($xmin,$xmax,$ymin,$ymax)=&boundaries($parstack,$safeeval,-2);
       my $xaxisvisible=(&Apache::lonxml::get_param('xaxisvisible',$parstack,$safeeval,-2)=~/on|true|yes|1/i?'true':'false');
       my $yaxisvisible=(&Apache::lonxml::get_param('yaxisvisible',$parstack,$safeeval,-2)=~/on|true|yes|1/i?'true':'false');
       my $gridvisible=(&Apache::lonxml::get_param('gridvisible',$parstack,$safeeval,-2)=~/on|true|yes|1/i?'true':'false');