--- loncom/homework/functionplotresponse.pm	2011/11/21 02:34:58	1.80
+++ loncom/homework/functionplotresponse.pm	2011/11/21 19:48:52	1.81
@@ -1,7 +1,7 @@
 # LearningOnline Network with CAPA
 # Functionplot responses
 #
-# $Id: functionplotresponse.pm,v 1.80 2011/11/21 02:34:58 www Exp $
+# $Id: functionplotresponse.pm,v 1.81 2011/11/21 19:48:52 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -654,10 +654,6 @@ sub start_functionplotrule {
    } else {
       $label='R'.$label;
    }
-   if ($Apache::functionplotresponse::splineorder{$label}) {
-       &Apache::lonxml::error(&mt('Rule indices must be unique.'));
-   }
-
 
    if ($target eq 'grade') {
 # Simply remember - in order - for later
@@ -772,9 +768,6 @@ sub start_functionplotvectorrule {
    } else {
       $label='R'.$label;
    }
-   if ($Apache::functionplotresponse::splineorder{$label}) {
-       &Apache::lonxml::error(&mt('Rule indices must be unique.'));
-   }
 
    if ($target eq 'grade') {
 # Simply remember - in order - for later
@@ -896,9 +889,6 @@ sub start_functionplotvectorsumrule {
    } else {
       $label='R'.$label;
    }
-   if ($Apache::functionplotresponse::splineorder{$label}) {
-       &Apache::lonxml::error(&mt('Rule indices must be unique.'));
-   }
    if ($target eq 'grade') {
 # Simply remember - in order - for later
       my $id=$Apache::inputtags::response[-1];
@@ -1382,6 +1372,22 @@ sub objectcoords {
    return ($env{'form.HWVAL_'.$id.'_'.$label.'_x'},
            $env{'form.HWVAL_'.$id.'_'.$label.'_y'});
 }
+
+sub attached {
+   my ($id,$vector,$object,$xmin,$xmax,$ymin,$ymax)=@_;
+   my ($xs,$xe,$ys,$ye)=&vectorcoords($id,$vector);
+   my ($xo,$yo)=&objectcoords($id,$object);
+   my $tolx=($xmax-$xmin)/100.;
+   my $toly=($ymax-$ymin)/100.;
+   my $tail=0;
+   my $tip=0;
+   &addlog("Proximity $vector ($xs,$xe,$ys,$ye) to $object ($xo,$yo)");
+   if ((abs($xs-$xo)<$tolx) && (abs($ys-$yo)<$toly)) { $tail=1; }
+   if ((abs($xe-$xo)<$tolx) && (abs($ye-$yo)<$toly)) { $tip=1; }
+   &addlog("Result tail:$tail tip:$tip");
+   return($tail,$tip);
+}
+
  
 sub vectorangle {
    my ($x,$y)=@_;
@@ -1459,6 +1465,55 @@ sub vectorcheck {
          return 0;
       }
    }
+   if ($attachpoint ne '') {
+      &addlog("Checking attached: ".$attachpoint);
+      my ($tail,$tip)=&attached($id,$vector,$attachpoint,$xmin,$xmax,$ymin,$ymax);
+      unless ($tail || $tip) {
+         &setfailed($label);
+         return 0;
+      }
+   }
+   if ($notattachpoint ne '') {
+      &addlog("Checking not attached: ".$notattachpoint);
+      my ($tail,$tip)=&attached($id,$vector,$notattachpoint,$xmin,$xmax,$ymin,$ymax);
+      if ($tail || $tip) {
+         &setfailed($label);
+         return 0;
+      }
+   }
+   if ($tailpoint ne '') {
+      &addlog("Checking tail: ".$tailpoint);
+      my ($tail,$tip)=&attached($id,$vector,$tailpoint,$xmin,$xmax,$ymin,$ymax);
+      unless ($tail) {
+         &setfailed($label);
+         return 0;
+      }
+   }
+   if ($nottailpoint ne '') {
+      &addlog("Checking not tail: ".$nottailpoint);
+      my ($tail,$tip)=&attached($id,$vector,$nottailpoint,$xmin,$xmax,$ymin,$ymax);
+      if ($tail) {
+         &setfailed($label);
+         return 0;
+      }
+   }
+   if ($tippoint ne '') {
+      &addlog("Checking tip: ".$tippoint);
+      my ($tail,$tip)=&attached($id,$vector,$tippoint,$xmin,$xmax,$ymin,$ymax);
+      unless ($tip) {
+         &setfailed($label);
+         return 0;
+      }
+   }
+   if ($nottippoint ne '') {
+      &addlog("Checking not tip: ".$nottippoint);
+      my ($tail,$tip)=&attached($id,$vector,$nottippoint,$xmin,$xmax,$ymin,$ymax);
+      if ($tip) {
+         &setfailed($label);
+         return 0;
+      }
+   }
+
    &addlog("Rule $label passed.");
    return 1;
 }