--- loncom/xml/lontexconvert.pm 2008/01/29 11:18:06 1.86 +++ loncom/xml/lontexconvert.pm 2011/02/10 20:07:00 1.98.2.1 @@ -1,7 +1,7 @@ # The LearningOnline Network with CAPA # TeX Conversion Module # -# $Id: lontexconvert.pm,v 1.86 2008/01/29 11:18:06 foxr Exp $ +# $Id: lontexconvert.pm,v 1.98.2.1 2011/02/10 20:07:00 raeburn Exp $ # # Copyright Michigan State University Board of Trustees # @@ -47,7 +47,8 @@ use Apache::lonlocal; use Apache::lonnet; use lib '/home/httpd/lib/perl/'; use LONCAPA; - +use URI::Escape; +use IO::Socket::INET; # ====================================================================== Header @@ -79,10 +80,7 @@ sub init_tth { $Apache::lontexconvert::messedup=0; -# we need this routine because &converted can get called from inside -# of the safespace (through &xmlparse('stuff') which doesn't -# allow the opcode for alarm, so we need to compile this before we get -# into the safe space since opcode checks only occur at compile time + sub convert_real { my ($texstring)=@_; my ($xmlstring,$errorstring); @@ -113,7 +111,8 @@ sub convert_real { # reasonably well to ⇔. If we get many more of these, # we're going to need to have a translation sub. # - $xmlstring=~s/\\rightleftharpoons/\&\#8660;/g; + my $lrharpoon = pack("U", 0x21cc); + $xmlstring=~s/\\rightleftharpoons/$lrharpoon/g; &Apache::lonxml::end_alarm(); return ($xmlstring,$errorstring); @@ -218,7 +217,9 @@ sub jsMath_converted { sub tex_engine { if (exists($env{'form.texengine'})) { - return $env{'form.texengine'}; + if ($env{'form.texengine'} ne '') { + return $env{'form.texengine'}; + } } if ($env{'request.course.id'} && exists($env{'course.'.$env{'request.course.id'}.'.texengine'})) { @@ -241,16 +242,52 @@ sub init_math_support { return; } +sub mimetex_valign { + my ($esc_texstring)=@_; + my $valign = 0; + my $lonhost = $Apache::lonnet::perlvar{'lonHostID'}; + my $hostname = &Apache::lonnet::hostname($lonhost); + my $path = '/cgi-bin/mimetex.cgi?'.$esc_texstring; + my $socket; + &Apache::lonxml::start_alarm(); + my $socket = IO::Socket::INET->new(PeerAddr => $hostname, + PeerPort => 'http(80)', + Proto => 'tcp'); + if ($socket) { + my $headreq = "HEAD $path HTTP/1.0\r\n\r\n"; + print $socket $headreq; + while (<$socket>) { + if (/Vertical\-Align\:\s*?([\-\d]+)/) { + $valign = $1; + } + } + $socket->close(); + } + &Apache::lonxml::end_alarm(); + return $valign; +} + sub mimetex_converted { my $texstring=shift; + +# Alt-Argument for screen readers + my $alt_string=$$texstring; + $alt_string=~s/\"/\'\'/g; + +# Is this displaystyle? + my $displaystyle=&displaystyle($texstring); +# Remove math environment delimiters + &clean_out_math_mode($texstring); if ($displaystyle) { $$texstring='\\displaystyle \\Large '.$$texstring; } - my $result=''; + my $esc_texstring = &uri_escape($$texstring); + my $valign = &mimetex_valign($esc_texstring); + my $result=''.$alt_string.''; if ($displaystyle) { $result='
'.$result.'
'; } @@ -266,6 +303,8 @@ sub converted { return &jsMath_converted($string); } elsif ($mode =~ /mimetex/i) { return &mimetex_converted($string); + } elsif ($mode =~ /raw/i) { + return $$string; } return &tth_converted($string); } @@ -350,7 +389,7 @@ sub msgtexconverted { sub algebra { use AlgParser; - my ($string,$target,$style)=@_; + my ($string,$target,$style,$parstack,$safeeval)=@_; my $parser = new AlgParserWithImplicitExpand; $string=&prepare_algebra($string); my $ret = $parser->parse($string); @@ -367,7 +406,9 @@ sub algebra { $latex='\\ensuremath{'.$latex.'}'; } if ($target eq 'web' || $target eq 'analyze') { - $result = &converted(\$latex); + my $display=&Apache::lonxml::get_param('display',$parstack,$safeeval); + $result = &converted(\$latex,$display); +# $result = &converted(\$latex); } else { $result = $latex; } @@ -414,8 +455,111 @@ sub postprocess_algebra { __END__ +=pod + +=head1 NAME + +Apache::lontexconvert; + +=head1 SYNOPSIS + +Access to tth/ttm + +This is part of the LearningOnline Network with CAPA project +described at http://www.lon-capa.org. + + +=head1 SUBROUTINES + +=over + +=item init_tth() + +Header + +=item convert_real() + + we need this routine because &converted can get called from inside + of the safespace (through &xmlparse('stuff') which doesn't + allow the opcode for alarm, so we need to compile this before we get + into the safe space since opcode checks only occur at compile time + +=item tth_converted() + + +=item clean_out_math_mode() + + +=item displaystyle() + + +=item jsMath_converted() + + +=item tex_engine() + + +=item init_math_support() + +=item mimetex_valign() + + Makes a HEAD call to /cgi-bin/mimetex.cgi via IO:: to retrieve the + vertical alignment, before the subsequent call to mimetex_converted() + which generates the tag and the corresponding image. + + Input: 1. $esc_texstring (escaped TeX to be rendered by mimetex). + Output: 1. $valign - number of pixels: positive or negative integer + which will be included in tag for mimetex image to + support vertical alignment of image within a line of text. + + If a server is running SSL, and Apache rewrite rules are in place + to rewrite requests for http to https, modification will most likely + be needed for pass through for HEAD requests for /cgi-bin/mimetex.cgi. + + Example rewrite rules which rewrite all http traffic to https, + except HEAD requests for /cgi-bin/mimetex.cgi are: + + + RewriteEngine On + RewriteLogLevel 0 + + RewriteCond %{HTTPS} off + RewriteCond %{HTTP:Host} (.*) + RewriteCond %{REQUEST_METHOD} !HEAD + RewriteRule ^/(.*) https://%1/$1 [R=301,L] + + RewriteCond %{HTTPS} off + RewriteCond %{HTTP:Host} (.*) + RewriteCond %{REQUEST_METHOD} HEAD + RewriteCond %{REQUEST_URI} !^/cgi-bin/mimetex.cgi + RewriteRule ^/(.*) https://%1/$1 [R=301,L] + + +=item mimetex_converted() + + +=item converted() + + +=item to_convert() + +message display + +=item smiley() + +??? + +=item msgtexconverted() + +=item algebra() + +=item prepare_algebra() + +=item postprocess_algebra() +=back +=cut