1:
2: # The LearningOnline Network with CAPA
3: # image click response style
4: #
5: # $Id: imageresponse.pm,v 1.48 2004/02/18 00:23:01 albertel Exp $
6: #
7: # Copyright Michigan State University Board of Trustees
8: #
9: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
10: #
11: # LON-CAPA is free software; you can redistribute it and/or modify
12: # it under the terms of the GNU General Public License as published by
13: # the Free Software Foundation; either version 2 of the License, or
14: # (at your option) any later version.
15: #
16: # LON-CAPA is distributed in the hope that it will be useful,
17: # but WITHOUT ANY WARRANTY; without even the implied warranty of
18: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19: # GNU General Public License for more details.
20: #
21: # You should have received a copy of the GNU General Public License
22: # along with LON-CAPA; if not, write to the Free Software
23: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24: #
25: # /home/httpd/html/adm/gpl.txt
26: #
27: # http://www.lon-capa.org/
28: #
29: #FIXME LATER assumes multiple possible submissions but only one is possible
30: #currently
31:
32: package Apache::imageresponse;
33: use strict;
34: use Image::Magick;
35: use Apache::randomlylabel;
36: use Apache::londefdef;
37: use Apache::Constants qw(:common :http);
38:
39: BEGIN {
40: &Apache::lonxml::register('Apache::imageresponse',('imageresponse'));
41: }
42:
43: sub start_imageresponse {
44: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
45: my $result;
46: #when in a radiobutton response use these
47: &Apache::lonxml::register('Apache::imageresponse',
48: ('foilgroup','foil','text','image','rectangle',
49: 'polygon','conceptgroup'));
50: push (@Apache::lonxml::namespace,'imageresponse');
51: my $id = &Apache::response::start_response($parstack,$safeeval);
52: if ($target eq 'meta') {
53: $result=&Apache::response::meta_package_write('imageresponse');
54: } elsif ($target eq 'analyze') {
55: my $part_id="$Apache::inputtags::part.$id";
56: push (@{ $Apache::lonhomework::analyze{"parts"} },$part_id);
57: }
58: return $result;
59: }
60:
61: sub end_imageresponse {
62: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
63: &Apache::response::end_response;
64: pop @Apache::lonxml::namespace;
65: &Apache::lonxml::deregister('Apache::imageresponse',('foilgroup','foil','text','image','rectangle','conceptgroup'));
66: my $result;
67: if ($target eq 'edit') { $result=&Apache::edit::end_table(); }
68: return $result;
69: }
70:
71: %Apache::response::foilgroup=();
72: sub start_foilgroup {
73: %Apache::response::foilgroup=();
74: $Apache::imageresponse::conceptgroup=0;
75: &Apache::response::setrandomnumber();
76: return '';
77: }
78:
79: sub getfoilcounts {
80: my ($parstack,$safeeval)=@_;
81:
82: my $max = &Apache::lonxml::get_param('max',$parstack,$safeeval,'-2');
83: # +1 since instructors will count from 1
84: my $count = $#{ $Apache::response::foilgroup{'names'} }+1;
85: if (&Apache::response::showallfoils()) { $max=$count; }
86: return ($count,$max);
87: }
88:
89: sub whichfoils {
90: my ($max)=@_;
91: if (!defined(@{ $Apache::response::foilgroup{'names'} })) { return; }
92: my @names = @{ $Apache::response::foilgroup{'names'} };
93: my @whichopt =();
94: while ((($#whichopt+1) < $max) && ($#names > -1)) {
95: &Apache::lonxml::debug("Have $#whichopt max is $max");
96: my $aopt;
97: if (&Apache::response::showallfoils()) {
98: $aopt=0;
99: } else {
100: $aopt=int(&Math::Random::random_uniform() * ($#names+1));
101: }
102: &Apache::lonxml::debug("From $#names elms, picking $aopt");
103: $aopt=splice(@names,$aopt,1);
104: &Apache::lonxml::debug("Picked $aopt");
105: push (@whichopt,$aopt);
106: }
107: return @whichopt;
108: }
109:
110: sub prep_image {
111: my ($image,$mode,$name)=@_;
112: my $part=$Apache::inputtags::part;
113: my $respid=$Apache::inputtags::response['-1'];
114: my $id=&Apache::loncommon::get_cgi_id();
115: my %x;
116: $x{"cgi.$id.BGIMG"}=&Apache::lonnet::escape($image);
117: my ($x,$y)=split(/:/,$Apache::lonhomework::history{"resource.$part.$respid.submission"});
118: #draws 2 xs on the image at the clicked location
119: #one in white and then one in red on top of the one in white
120: if (defined($x) && $x=~/\S/ && defined($y) && $y =~/\S/) {
121: $x{"cgi.$id.LINECOUNT"}=4;
122: my $length = 6;
123: my $width = 1;
124: my $extrawidth = 2;
125: my $xmin=($x-$length);
126: my $xmax=($x+$length);
127: my $ymin=($y-$length);
128: my $ymax=($y+$length);
129:
130: $x{"cgi.$id.LINE0"}=
131: join(':',(($xmin),($ymin),($xmax),($ymax),
132: "FFFFFF",($width+$extrawidth)));
133: $x{"cgi.$id.LINE1"}=
134: join(':',(($xmin),($ymax),($xmax),($ymin),
135: "FFFFFF",($width+$extrawidth)));
136: $x{"cgi.$id.LINE2"}=
137: join(':',(($xmin),($ymin),($xmax),($ymax),
138: "FF0000",($width)));
139: $x{"cgi.$id.LINE3"}=
140: join(':',(($xmin),($ymax),($xmax),($ymin),
141: "FF0000",($width)));
142: }
143: if ($mode eq 'answer') {
144: my $width = 1;
145: my $extrawidth = 2;
146: my @areas = @{ $Apache::response::foilgroup{"$name.area"} };
147: foreach my $area (@areas) {
148: if ($area=~/^rectangle:/) {
149: my ($x1,$y1,$x2,$y2)=
150: ($area=~m/rectangle:\(([0-9]+),([0-9]+)\)\-\(([0-9]+),([0-9]+)\)/);
151: my $i=$x{"cgi.$id.BOXCOUNT"}++;
152: $x{"cgi.$id.BOX$i"}=join(':',($x1,$y1,$x2,$y2,"FFFFFF",
153: ($width+$extrawidth)));
154: $i=$x{"cgi.$id.BOXCOUNT"}++;
155: $x{"cgi.$id.BOX$i"}=join(':',($x1,$y1,$x2,$y2,"00FF00",$width));
156: } elsif ($area=~/^polygon:(.*)/) {
157: my $i=$x{"cgi.$id.POLYCOUNT"}++;
158: $x{"cgi.$id.POLYOPT$i"}=join(':',("FFFFFF",($width+$extrawidth)));
159: $x{"cgi.$id.POLY$i"}=$1;
160: $i=$x{"cgi.$id.POLYCOUNT"}++;
161: $x{"cgi.$id.POLYOPT$i"}=join(':',("00FF00",$width));
162: $x{"cgi.$id.POLY$i"}=$1;
163: }
164: }
165: }
166: &Apache::lonnet::appenv(%x);
167: return $id;
168: }
169:
170: sub displayfoils {
171: my ($target,@whichopt) = @_;
172: my $result ='';
173: my $name;
174: my $temp=1;
175: foreach $name (@whichopt) {
176: $result.=$Apache::response::foilgroup{"$name.text"};
177: &Apache::lonxml::debug("Text is $result");
178: if ($target eq 'tex') {$result.="\\vskip 0 mm \n";} else {$result.="<br />\n";}
179: my $image=$Apache::response::foilgroup{"$name.image"};
180: &Apache::lonxml::debug("image is $image");
181: if ( $target eq 'web' && $image !~ /^http:/ ) {
182: $image=&clean_up_image($image);
183: }
184: &Apache::lonxml::debug("image is $image");
185: if ( &Apache::response::show_answer() ) {
186: if ($target eq 'tex') {
187: $result.=$Apache::response::foilgroup{"$name.image"}."\\vskip 0 mm \n";
188: } else {
189: my $token=&prep_image($image,'answer',$name);
190: $result.="<img src=\"/adm/randomlabel.png?token=$token\" /><br />\n";
191: }
192: } else {
193: if ($target eq 'tex') {
194: $result.=$Apache::response::foilgroup{"$name.image"}."\\vskip 0 mm \n";
195: } else {
196: my $id=$Apache::inputtags::response['-1'];
197: my $token=&prep_image($image);
198: my $temp=1;
199: $result.="<input type=\"image\" name=\"HWVAL_$id:$temp\" ".
200: "src=\"/adm/randomlabel.png?token=$token\" /><br />\n";
201: }
202: }
203: $temp++;
204: }
205: return $result;
206: }
207:
208: sub clean_up_image {
209: my ($image)=@_;
210: if ($image =~ /\s*<img\s*/) {
211: ($image) = ($image =~ /src\s*=\s*\"([^\"]+)\"/i);
212: if ($image !~ /^http:/) {
213: $image=&Apache::lonnet::hreflocation('',$image);
214: }
215: if (!$image) {
216: $image='/home/httpd/html/adm/lonKaputt/lonlogo_broken.gif';
217: }
218: } else {
219: $image=&Apache::lonnet::filelocation($Apache::lonxml::pwd[-1],$image);
220: if (&Apache::lonnet::repcopy($image) ne OK) {
221: $image='/home/httpd/html/adm/lonKaputt/lonlogo_broken.gif';
222: }
223: }
224: return $image;
225: }
226:
227: sub gradefoils {
228: my (@whichopt) = @_;
229: my $x;
230: my $y;
231: my $result;
232: my $id=$Apache::inputtags::response['-1'];
233: my $temp=1;
234: foreach my $name (@whichopt) {
235: $x=$ENV{"form.HWVAL_$id:$temp.x"};
236: $y=$ENV{"form.HWVAL_$id:$temp.y"};
237: &Apache::lonxml::debug("Got a x of $x and a y of $y for $name");
238: if (defined($x) && defined($y) &&
239: defined(@{ $Apache::response::foilgroup{"$name.area"} })) {
240: my @areas = @{ $Apache::response::foilgroup{"$name.area"} };
241: my $grade="INCORRECT";
242: foreach my $area (@areas) {
243: &Apache::lonxml::debug("Area is $area for $name");
244: $area =~ m/([a-z]*):/;
245: &Apache::lonxml::debug("Area of type $1");
246: if ($1 eq 'rectangle') {
247: $grade=&grade_rectangle($area,$x,$y);
248: } elsif ($1 eq 'polygon') {
249: $grade=&grade_polygon($area,$x,$y);
250: } else {
251: &Apache::lonxml::error("Unknown area style $area");
252: }
253: &Apache::lonxml::debug("Area said $grade");
254: if ($grade eq 'APPROX_ANS') { last; }
255: }
256: &Apache::lonxml::debug("Foil was $grade");
257: if ($grade eq 'INCORRECT') { $result= 'INCORRECT'; }
258: if (($grade eq 'APPROX_ANS') && ($result ne 'APPROX_ANS')) { $result=$grade; }
259: &Apache::lonxml::debug("Question is $result");
260: $temp++;
261: }
262: }
263: $Apache::lonhomework::results{"resource.$Apache::inputtags::part.$id.submission"}="$x:$y";
264: $Apache::lonhomework::results{"resource.$Apache::inputtags::part.$id.awarddetail"}=$result;
265: return '';
266: }
267:
268: sub end_foilgroup {
269: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
270: my $result='';
271: my @whichopt;
272: if ($target eq 'web' || $target eq 'grade' || $target eq 'tex' ||
273: $target eq 'analyze') {
274: my ($count,$max) = &getfoilcounts($parstack,$safeeval);
275: if ($count>$max) { $count=$max }
276: &Apache::lonxml::debug("Count is $count from $max");
277: @whichopt = &whichfoils($max);
278: if ($target eq 'web' || $target eq 'tex') {
279: $result=&displayfoils($target,@whichopt);
280: } elsif ($target eq 'grade') {
281: if ( defined $ENV{'form.submitted'}) { &gradefoils(@whichopt); }
282: } elsif ( $target eq 'analyze') {
283: &Apache::response::analyze_store_foilgroup(\@whichopt,
284: ['text','image','area']);
285: }
286: } elsif ($target eq 'edit') {
287: $result=&Apache::edit::end_table();
288: }
289: return $result;
290: }
291:
292: sub start_conceptgroup {
293: $Apache::imageresponse::conceptgroup=1;
294: %Apache::response::conceptgroup=();
295: return '';
296: }
297:
298: sub end_conceptgroup {
299: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
300: $Apache::imageresponse::conceptgroup=0;
301: my $result;
302: if ($target eq 'web' || $target eq 'grade' || $target eq 'tex' ||
303: $target eq 'analyze') {
304: &Apache::response::pick_foil_for_concept($target,
305: ['area','text','image'],
306: \%Apache::hint::image,
307: $parstack,$safeeval);
308: } elsif ($target eq 'edit') {
309: $result=&Apache::edit::end_table();
310: }
311: return $result;
312: }
313:
314: sub insert_foil {
315: return '
316: <foil>
317: <image></image>
318: <text></text>
319: <rectangle></rectangle>
320: </foil>
321: ';
322: }
323:
324: $Apache::imageresponse::curname='';
325: sub start_foil {
326: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
327: if ($target eq 'web' || $target eq 'grade' || $target eq 'tex' ||
328: $target eq 'analyze') {
329: my $name = &Apache::lonxml::get_param('name',$parstack,$safeeval);
330: if ($name eq '') { $name=$Apache::lonxml::curdepth; }
331: if ( $Apache::imageresponse::conceptgroup
332: && !&Apache::response::showallfoils()) {
333: push(@{ $Apache::response::conceptgroup{'names'} }, $name);
334: } else {
335: push(@{ $Apache::response::foilgroup{'names'} }, $name);
336: }
337: $Apache::imageresponse::curname=$name;
338: }
339: return '';
340: }
341:
342: sub end_foil {
343: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
344: my $result;
345: if ($target eq 'edit') {
346: $result=&Apache::edit::end_table();
347: }
348: return $result;
349: }
350:
351: sub start_text {
352: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
353: my $result='';
354: if ($target eq 'web' || $target eq 'tex' || $target eq 'analyze') {
355: &Apache::lonxml::startredirection;
356: } elsif ($target eq 'edit') {
357: my $descr=&Apache::lonxml::get_all_text('/text',$parser);
358: $result=&Apache::edit::tag_start($target,$token,'Task Description').
359: &Apache::edit::editfield($token->[1],$descr,'Text',60,2).
360: &Apache::edit::end_row();
361: } elsif ($target eq "modified") {
362: $result=$token->[4].&Apache::edit::modifiedfield('/text',$parser);
363: }
364: return $result;
365: }
366:
367: sub end_text {
368: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
369: my $result;
370: if ($target eq 'web' || $target eq 'tex' || $target eq 'analyze') {
371: my $name = $Apache::imageresponse::curname;
372: if ( $Apache::imageresponse::conceptgroup
373: && !&Apache::response::showallfoils() ) {
374: $Apache::response::conceptgroup{"$name.text"} = &Apache::lonxml::endredirection;
375: } else {
376: $Apache::response::foilgroup{"$name.text"} = &Apache::lonxml::endredirection;
377: }
378: } elsif ($target eq 'edit') {
379: $result=&Apache::edit::end_table();
380: }
381: return $result;
382: }
383:
384: sub start_image {
385: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
386: my $result='';
387: if ($target eq 'web' || $target eq 'tex' || $target eq 'analyze') {
388: &Apache::lonxml::startredirection;
389: } elsif ($target eq 'edit') {
390: my $bgimg=&Apache::lonxml::get_all_text('/image',$parser);
391: $Apache::edit::bgimgsrc=$bgimg;
392: $Apache::edit::bgimgsrcdepth=$Apache::lonxml::curdepth;
393:
394: $result=&Apache::edit::tag_start($target,$token,'Clickable Image').
395: &Apache::edit::editline($token->[1],$bgimg,'Image Source File',40);
396: $result.=&Apache::edit::browse(undef,'textnode').' ';
397: $result.=&Apache::edit::search(undef,'textnode').
398: &Apache::edit::end_row();
399: } elsif ($target eq "modified") {
400: $result=$token->[4].&Apache::edit::modifiedfield('/image',$parser);
401: }
402: return $result;
403: }
404:
405: sub end_image {
406: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
407: my $result;
408: my $name = $Apache::imageresponse::curname;
409: if ($target eq 'web') {
410: my $image = &Apache::lonxml::endredirection;
411: &Apache::lonxml::debug("original image is $image");
412: if ( $Apache::imageresponse::conceptgroup
413: && !&Apache::response::showallfoils()) {
414: $Apache::response::conceptgroup{"$name.image"} = $image;
415: } else {
416: $Apache::response::foilgroup{"$name.image"} = $image;
417: }
418: } elsif ($target eq 'analyze') {
419: my $image = &Apache::lonxml::endredirection;
420: if ( $Apache::imageresponse::conceptgroup
421: && !&Apache::response::showallfoils()) {
422: $Apache::response::conceptgroup{"$name.image"} = $image;
423: } else {
424: $Apache::response::foilgroup{"$name.image"} = $image;
425: }
426: } elsif ($target eq 'edit') {
427: $result=&Apache::edit::end_table();
428: } elsif ($target eq 'tex') {
429: my $src = &Apache::lonxml::endredirection;
430: $src=&Apache::lonnet::filelocation($Apache::lonxml::pwd[-1],$src);
431: my $width_param = '';
432: my $height_param = '';
433: my $scaling = .3;
434: my $image = Image::Magick->new;
435: my $current_figure = $image->Read($src);
436: $width_param = $image->Get('width') * $scaling;;
437: $height_param = $image->Get('height') * $scaling;;
438: undef $image;
439: my $epssrc = $src;
440: $epssrc =~ s/(\.gif|\.jpg)$/\.eps/i;
441: if (not -e $epssrc) {
442: my $localfile = $epssrc;
443: $localfile =~ s/.*(\/res)/$1/;
444: my $file;
445: my $path;
446: if ($localfile =~ m!(.*)/([^/]*)$!) {
447: $file = $2;
448: $path = $1.'/';
449: }
450: my $signal_eps = 0;
451: my @content_directory = &Apache::lonnet::dirlist($path);
452: for (my $iy=0;$iy<=$#content_directory;$iy++) {
453: my @tempo_array = split(/&/,$content_directory[$iy]);
454: $content_directory[$iy] = $tempo_array[0];
455: if ($file eq $tempo_array[0]) {
456: $signal_eps = 1;
457: last;
458: }
459: }
460: if ($signal_eps) {
461: my $eps_file = &Apache::lonnet::getfile($localfile);
462: } else {
463: $localfile = $src;
464: $localfile =~ s/.*(\/res)/$1/;
465: my $as = &Apache::lonnet::getfile($src);
466: }
467: }
468: my $file;
469: my $path;
470: if ($src =~ m!(.*)/([^/]*)$!) {
471: $file = $2;
472: $path = $1.'/';
473: }
474: my $newsrc = $src;
475: $newsrc =~ s/(\.gif|\.jpg|\.jpeg)$/\.eps/i;
476: $file=~s/(\.gif|\.jpg|\.jpeg)$/\.eps/i;
477: #do we have any specified size of the picture?
478: my $TeXwidth = &Apache::lonxml::get_param('TeXwidth',$parstack,$safeeval);
479: my $TeXheight = &Apache::lonxml::get_param('TeXheight',$parstack,$safeeval);
480: my $width = &Apache::lonxml::get_param('width',$parstack,$safeeval);
481: if ($TeXwidth ne '') {
482: $width_param = $TeXwidth;
483: } elsif ($TeXheight ne '') {
484: $width_param = $TeXheight/$height_param*$width_param;
485: } elsif ($width ne '') {
486: $width_param = $width*$scaling;
487: }
488: #where can we find the picture?
489: if (-e $newsrc) {
490: if ($path) {
491: $Apache::response::foilgroup{"$name.image"} ='\vskip 0 mm \noindent\graphicspath{{'.$path.'}}\includegraphics[width='.$width_param.' mm]{'.$file.'} ';
492: }
493: } else {
494: #care about eps dynamical generation
495: $Apache::response::foilgroup{"$name.image"}='\vskip 0 mm '.&Apache::londefdef::eps_generation($src,$file,$width_param);
496: }
497: }
498: return $result;
499: }
500:
501: sub start_rectangle {
502: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
503: my $result='';
504: if ($target eq 'web' || $target eq 'grade' || $target eq 'tex' ||
505: $target eq 'analyze') {
506: &Apache::lonxml::startredirection;
507: } elsif ($target eq 'edit') {
508: my $coords=&Apache::lonxml::get_all_text('/rectangle',$parser);
509: $result=&Apache::edit::tag_start($target,$token,'Rectangle').
510: &Apache::edit::editline($token->[1],$coords,'Coordinate Pairs',40).
511: &Apache::edit::entercoord(undef,'textnode',undef,undef,'box').
512: &Apache::edit::end_row();
513: } elsif ($target eq "modified") {
514: &Apache::edit::deletecoorddata();
515: $result=$token->[4].&Apache::edit::modifiedfield('/rectangle',$parser);
516: }
517: return $result;
518: }
519:
520: sub grade_rectangle {
521: my ($spec,$x,$y) = @_;
522: &Apache::lonxml::debug("Spec is $spec");
523: my ($x1,$y1,$x2,$y2)=($spec=~m/rectangle:\(([0-9]+),([0-9]+)\)\-\(([0-9]+),([0-9]+)\)/);
524: &Apache::lonxml::debug("Point $x1,$y1,$x2,$y2");
525: if ($x1 > $x2) { my $temp=$x1;$x1=$x2;$x2=$temp; }
526: if ($y1 > $y2) { my $temp=$y1;$y1=$y2;$y2=$temp; }
527: if (($x >= $x1) && ($x <= $x2) && ($y >= $y1) && ($y <= $y2)) {
528: return 'APPROX_ANS';
529: }
530: return 'INCORRECT';
531: }
532:
533: sub end_rectangle {
534: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
535: my $result;
536: if ($target eq 'web' || $target eq 'grade' || $target eq 'tex' ||
537: $target eq 'analyze') {
538: my $name = $Apache::imageresponse::curname;
539: my $area = &Apache::lonxml::endredirection;
540: &Apache::lonxml::debug("out is $area for $name");
541: if ( $Apache::imageresponse::conceptgroup
542: && !&Apache::response::showallfoils()) {
543: push @{ $Apache::response::conceptgroup{"$name.area"} },"rectangle:$area";
544: } else {
545: push @{ $Apache::response::foilgroup{"$name.area"} },"rectangle:$area";
546: }
547: } elsif ($target eq 'edit') {
548: $result=&Apache::edit::end_table();
549: }
550: return $result;
551: }
552:
553: sub start_polygon {
554: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
555: my $result='';
556: if ($target eq 'web' || $target eq 'grade' || $target eq 'tex' ||
557: $target eq 'analyze') {
558: &Apache::lonxml::startredirection;
559: } elsif ($target eq 'edit') {
560: my $coords=&Apache::lonxml::get_all_text('/polygon',$parser);
561: $result=&Apache::edit::tag_start($target,$token,'Polygon').
562: &Apache::edit::editline($token->[1],$coords,'Coordinate list',40).
563: &Apache::edit::entercoord(undef,'textnode',undef,undef,'polygon').
564: &Apache::edit::end_row();
565: } elsif ($target eq "modified") {
566: $result=$token->[4].&Apache::edit::modifiedfield('/polygon',$parser);
567: }
568: return $result;
569: }
570:
571: sub grade_polygon {
572: my ($spec,$x,$y) = @_;
573: &Apache::lonxml::debug("Spec is $spec");
574: $spec=~s/^polygon://;
575: my @polygon;
576: foreach my $coord (split('-',$spec)) {
577: my ($x,$y)=($coord=~m/\(([0-9]+),([0-9]+)\)/);
578: &Apache::lonxml::debug("x $x y $y");
579: push @polygon, {'x'=>$x,'y'=>$y};
580: }
581: #make end point start point
582: push @polygon, $polygon[0];
583: # cribbed from
584: # http://geometryalgorithms.com/Archive/algorithm_0103/algorithm_0103.htm
585: my $crossing = 0; # the crossing number counter
586:
587: # loop through all edges of the polygon
588: for (my $i=0; $i<$#polygon; $i++) { # edge from V[i] to V[i+1]
589: if ((($polygon[$i]->{'y'} <= $y)
590: && ($polygon[$i+1]->{'y'} > $y)) # an upward crossing
591: ||
592: (($polygon[$i]->{'y'} > $y)
593: && ($polygon[$i+1]->{'y'} <= $y))) { # a downward crossing
594: # compute the actual edge-ray intersect x-coordinate
595: my $vt = ($y - $polygon[$i]->{'y'})
596: / ($polygon[$i+1]->{'y'} - $polygon[$i]->{'y'});
597: if ($x < $polygon[$i]->{'x'} + $vt *
598: ($polygon[$i+1]->{'x'} - $polygon[$i]->{'x'})) { # x<intersect
599: $crossing++; # a valid crossing of y=P.y right of P.x
600: }
601: }
602: }
603:
604: # 0 if even (out), and 1 if odd (in)
605: if ($crossing%2) {
606: return 'APPROX_ANS';
607: } else {
608: return 'INCORRECT';
609: }
610: }
611:
612: sub end_polygon {
613: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
614: my $result;
615: if ($target eq 'web' || $target eq 'grade' || $target eq 'tex' ||
616: $target eq 'analyze') {
617: my $name = $Apache::imageresponse::curname;
618: my $area = &Apache::lonxml::endredirection;
619: $area=~s/\s*//g;
620: &Apache::lonxml::debug("out is $area for $name");
621: if ( $Apache::imageresponse::conceptgroup
622: && !&Apache::response::showallfoils()) {
623: push @{ $Apache::response::conceptgroup{"$name.area"} },"polygon:$area";
624: } else {
625: push @{ $Apache::response::foilgroup{"$name.area"} },"polygon:$area";
626: }
627: } elsif ($target eq 'edit') {
628: $result=&Apache::edit::end_table();
629: }
630: return $result;
631: }
632: 1;
633: __END__
634:
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