--- loncom/homework/functionplotresponse.pm	2010/11/23 23:55:01	1.46
+++ loncom/homework/functionplotresponse.pm	2010/11/24 02:53:13	1.47
@@ -1,7 +1,7 @@
 # LearningOnline Network with CAPA
 # option list style responses
 #
-# $Id: functionplotresponse.pm,v 1.46 2010/11/23 23:55:01 www Exp $
+# $Id: functionplotresponse.pm,v 1.47 2010/11/24 02:53:13 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -330,7 +330,7 @@ ENDYOFFAXISLABEL
 }
 
 sub plot_script {
-   my ($id,$function,$fixed,$label,$color,$xmin,$xmax)=@_;
+   my ($id,$function,$fixed,$label,$color,$xmin,$xmax,$thickness)=@_;
    $label=~s/\W//g;
    if (($label) && ($label!~/^[A-Za-z]/)) {
       $label='C'.$label;
@@ -354,7 +354,8 @@ sub plot_script {
    if ($fixed) {
       return "document.ggbApplet_$id.evalCommand('$label=Function[$function,$xmin,$xmax]');\n".
              ($visible?'':"document.ggbApplet_$id.setLabelVisible('$label', false);\n").
-             ($color?"document.ggbApplet_$id.setColor('$label',$rc,$gc,$bc);\n":'');
+             ($color?"document.ggbApplet_$id.setColor('$label',$rc,$gc,$bc);\n":'').
+             ($thickness?"document.ggbApplet_$id.setLineThickness('$label',$thickness);\n":'');
    } else {
        return "document.ggbApplet_$id.evalCommand('y=$function');\n";
    }
@@ -393,6 +394,8 @@ sub start_backgroundplot {
    my $result='';
    my $internalid = $Apache::inputtags::part.'_'.$Apache::inputtags::response[-1];
    my $function=&Apache::lonxml::get_param('function',$parstack,$safeeval);
+   my $xinitial=&Apache::lonxml::get_param('xinitial',$parstack,$safeeval);
+   my $xfinal=&Apache::lonxml::get_param('xfinal',$parstack,$safeeval);
    my $label=&Apache::lonxml::get_param('label',$parstack,$safeeval);
    my $color=&Apache::lonxml::get_param('color',$parstack,$safeeval);
    $color=~s/[^a-fA-F0-9]//gs;
@@ -402,11 +405,17 @@ sub start_backgroundplot {
    unless ($function) { $function="0"; }
    if ($target eq 'web') {
       my ($xmin,$xmax,$ymin,$ymax)=&boundaries($parstack,$safeeval,-3);
-      $result.=&plot_script($internalid,$function,$fixed,$label,$color,$xmin,$xmax);
+      unless (defined($xinitial)) { $xinitial=$xmin; }
+      unless (defined($xfinal)) { $xfinal=$xmax; }
+      $result.=&plot_script($internalid,$function,$fixed,$label,$color,$xinitial,$xfinal);
    } 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('Initial x-value (optional):','xinitial',
+                                     $token,'8').
+             &Apache::edit::text_arg('Final x-value (optional):','xfinal',
+                                     $token,'8').
              &Apache::edit::text_arg('Label on Plot:','label',
                                      $token,'8').
              &Apache::edit::text_arg('Color (hex code):','color',
@@ -416,7 +425,7 @@ sub start_backgroundplot {
              &Apache::edit::end_row();
   } elsif ($target eq 'modified') {
     my $constructtag=&Apache::edit::get_new_args($token,$parstack,
-                                                 $safeeval,'function','label','color','fixed');
+                                                 $safeeval,'function','label','xinitial','xfinal','color','fixed');
     if ($constructtag) { $result=&Apache::edit::rebuild_tag($token); }
   }
   return $result;
@@ -826,12 +835,15 @@ sub start_functionplotresponse {
              &Apache::edit::select_arg('y-axis visible:','yaxisvisible',
                                   ['yes','no'],$token).'<br />'.
              &Apache::edit::select_arg('Grid visible:','gridvisible',
-                                  ['yes','no'],$token).
+                                  ['yes','no'],$token).'<br />'.
+             &Apache::edit::text_arg('Background plot(s) for answer (function:xmin:xmax,function:xmin:xmax,...):',
+                                         'answerdisplay',$token,'50');
+
              &Apache::edit::end_row().&Apache::edit::start_spanning_row();
   } elsif ($target eq 'modified') {
     my $constructtag=&Apache::edit::get_new_args($token,$parstack,
                                                  $safeeval,'xlabel','xmin','xmax','ylabel','ymin','ymax',
-                                                           'xaxisvisible','yaxisvisible','gridvisible');
+                                                           'xaxisvisible','yaxisvisible','gridvisible','answerdisplay');
     if ($constructtag) { $result = &Apache::edit::rebuild_tag($token); }
 
   } elsif ($target eq 'meta') {
@@ -1162,8 +1174,24 @@ sub end_functionplotelements {
   if ($target eq 'edit' ) {
      $result=&Apache::edit::end_table();
   } elsif ($target eq 'web') {
-# Now is the time to render all of the stored splines
      my ($xmin,$xmax,$ymin,$ymax)=&boundaries($parstack,$safeeval,-2);
+
+# Are we in show answer mode?
+     my $showanswer=&Apache::response::show_answer();
+     if ($showanswer) {
+# Render answerdisplay
+        my $answerdisplay=&Apache::lonxml::get_param('answerdisplay',$parstack,$safeeval,-2);
+        if ($answerdisplay=~/\S/s) {
+           foreach my $plot (split(/\s*\,\s*/,$answerdisplay)) {
+              my ($func,$xl,$xh)=split(/\s*\:\s*/,$plot);
+              if ((!defined($xl)) || ($xl eq '')) { $xl=$xmin; }
+              if ((!defined($xh)) || ($xh eq '')) { $xh=$xmax; }
+              $result.=&plot_script($internalid,$func,1,'','00aa00',$xl,$xh,6);
+           }
+        }
+     }
+
+# Now is the time to render all of the stored splines
      foreach my $label (keys(%Apache::functionplotresponse::splineorder)) {
         $result.=&generate_spline($internalid,$label,$xmin,$xmax,$ymin,$ymax);
      }