use strict;
use utf8;
+use POSIX qw(setsid);
use Pod::Usage;
use Getopt::Long;
+use Cwd qw(getcwd abs_path);
use Glib qw(TRUE FALSE);
use Gtk2 -init;
use Gtk2::MozEmbed;
=cut
+my $mozembed;
+
GetOptions ("help|?" => \$help,
"last" => \$last,
+ "mozembed" => \$mozembed,
"n=s" => \$start,
"splash!" => \$splash,
"start=s" => \$start,
die "techtalk-pse: cannot use --start and --last options together\n"
if defined $last && defined $start;
-die "techtalk-pse: too many arguments\n" if @ARGV >= 2;
+die "techtalk-pse: too many arguments\n" if !$mozembed && @ARGV >= 2;
+
+# Get the true name of the program.
+$0 = abs_path ($0);
# Locate the talk.
if (@ARGV > 0) {
}
}
-# MozEmbed initialization.
-Gtk2::MozEmbed->set_profile_path ("$ENV{HOME}/.@PACKAGE@", "Tech Talk PSE");
+# Get the talk directory and set environment variable $talkdir
+# which is inherited by all the scripts.
+my $talkdir = getcwd;
+$ENV{talkdir} = $talkdir;
# Get the files.
my @files;
-my %groups;
+my %files;
sub reread_directory
{
@files = ();
- %groups = ();
+ my $i = 0;
foreach (glob ("*")) {
- if (/^(\d+)([A-Z])?(?:-.*)\.(html|sh|txt)$/) {
+ if (/^(\d+)(?:-.*)\.(html|sh)$/) {
print STDERR "reading $_\n" if $verbose;
my $seq = $1;
- my $pos = $2 || "A";
- my $ext = $3;
+ my $ext = $2;
warn "techtalk-pse: $_: command file is not executable (+x)\n"
if $ext eq "sh" && ! -x $_;
- my $h = { name => $_, seq => $1, pos => $2, ext => $3 };
+ my $h = { name => $_, seq => $1, ext => $2, i => $i };
push @files, $h;
-
- $groups{$seq} = [] unless exists $groups{$seq};
- push @{$groups{$seq}}, $h;
+ $files{$_} = $h;
+ $i++;
} else {
print STDERR "ignoring $_\n" if $verbose;
}
}
+
+ if (@files > 0) {
+ $files[0]->{first} = 1;
+ $files[$#files]->{last} = 1;
+ }
}
reread_directory ();
print STDERR "read ", 0+@files, " files\n" if $verbose;
warn "techtalk-pse: no files found, continuing anyway ...\n"
}
+# Run with --mozembed: see below.
+run_mozembed () if $mozembed;
+
+# Else, normal run of the program ...
+
# Work out what slide we're starting on.
my $current;
if (defined $current) {
my $w = Gtk2::AboutDialog->new;
$w->set_authors ("Richard W.M. Jones");
$w->set_comments (
- "Superior technical demonstration software\n".
- "\n".
- "Keys\n".
- "↑ — Go back one slide\n".
- "↓ — Go forward one slide\n"
+ "Superior technical demonstration software\n"
);
$w->set_program_name ("Tech Talk Platinum Supreme Edition (PSE)");
$w->set_version ("@VERSION@");
$w->set_website ("http://people.redhat.com/~rjones");
$w->set_license ("GNU General Public License v2 or above");
- $w->signal_connect (destroy => sub { Gtk2->main_quit });
- $w->show_all;
+ $w->run;
+ print STDERR "calling \$w->destroy on about dialog\n" if $verbose;
+ $w->destroy;
+
+ # The dialog doesn't really get destroyed here. We have
+ # to add this hack to really destroy it.
+ Glib::Idle->add (sub { Gtk2->main_quit; return FALSE; });
Gtk2->main;
}
+MAIN: while (1) {
+ if (defined $current) {
+ my $go = show_slide ($current);
+ if (defined $go) {
+ print STDERR "go = $go\n" if $verbose;
+ last MAIN if $go eq "QUIT";
+
+ my $i = $current->{i};
+ print STDERR "i = $i\n" if $verbose;
+ $i-- if $go eq "PREV" && $i > 0;
+ $i++ if $go eq "NEXT" && $i+1 < @files;
+ $i = 0 if $go eq "FIRST";
+ $i = $#files if $go eq "LAST";
+ $i = $1 if $go =~ /^I_(\d+)$/;
+ $current = $files[$i];
+ }
+ } else {
+ print "No slides found. Press any key to reload directory ...\n";
+ $_ = <STDIN>;
+ }
+
+ # Reread directory between slides.
+ reread_directory ();
+
+ if (defined $current && !exists $files{$current->{name}}) {
+ # Current slide was deleted.
+ undef $current;
+ $current = $files[0] if @files;
+ }
+}
+
+sub show_slide
+{
+ my $slide = shift;
+
+ # Display an HTML page.
+ if ($slide->{ext} eq "html") {
+ # MozEmbed is incredibly crashy, so we run ourself as a
+ # subprocess, so when it segfaults we don't care. If all goes
+ # well and it doesn't crash, it should print a line 'RESULT FOO'
+ # where 'FOO' is the instruction (eg. 'NEXT', 'PREV', 'QUIT' etc).
+ my @cmd = ($0, "--mozembed", $talkdir, $slide->{name});
+ print STDERR "running subcommand: ", join (" ", @cmd), "\n"
+ if $verbose;
+ open CMD, "-|", @cmd
+ or die "failed to execute subcommand: ", join(" ", @cmd), ": $!\n";
+ my $r;
+ while (<CMD>) {
+ if (/^RESULT ([A-Z]+.*)/) {
+ $r = $1;
+ print STDERR "subcommand result: $r\n" if $verbose;
+ last;
+ }
+ }
+ # No RESULT line? Subcommand probably segfaulted, just
+ # continue to next slide.
+ $r ||= "NEXT";
+ return $r;
+ }
+ # Run a shell command.
+ elsif ($slide->{ext} eq "sh") {
+ my $pid;
+ # http://docstore.mik.ua/orelly/perl/cookbook/ch10_17.htm
+ local *run_process = sub {
+ $pid = fork ();
+ die "fork: $!" unless defined $pid;
+ unless ($pid) {
+ # Child.
+ POSIX::setsid ();
+ exec ("./".$slide->{name});
+ die "failed to execute command: ", $slide->{name}, ": $!";
+ }
+ # Parent returns.
+ };
+ local *kill_process = sub {
+ print STDERR "sending TERM signal to process group $pid\n"
+ if $verbose;
+ kill "TERM", -$pid;
+ };
+ run_process ();
+
+ my $r = "NEXT";
+
+ my $w = Gtk2::Window->new ();
+
+ my $s = $w->get_screen;
+ $w->set_default_size ($s->get_width, -1);
+ $w->move (0, 0);
+ $w->set_decorated (0);
+
+ my $bbox =
+ make_button_bar ((exists $slide->{first}),
+ (exists $slide->{last}),
+ sub { $r = $_[0]; $w->destroy },
+ restart => sub {
+ kill_process ();
+ run_process ();
+ },
+ );
+
+ $w->add ($bbox);
+
+ $w->signal_connect (destroy => sub {
+ Gtk2->main_quit;
+ return FALSE;
+ });
+ $w->show_all ();
+
+ Gtk2->main;
+
+ kill_process ();
+ print STDERR "returning r=$r\n" if $verbose;
+ return $r;
+ }
+}
+# If invoked with the --mozembed parameter then we just display a
+# single page. This is just to prevent crashes in MozEmbed from
+# killing the whole program.
+sub run_mozembed
+{
+ my $w = Gtk2::Window->new ();
+ my $vbox = Gtk2::VBox->new ();
+ my $moz = Gtk2::MozEmbed->new ();
+ reread_directory ();
+ my $name = $ARGV[1];
+ $current = $files{$name};
+ my $url = "file://$talkdir/$name";
+ my $bbox =
+ make_button_bar ($current->{first}, $current->{last},
+ sub { print "RESULT ", $_[0], "\n"; $w->destroy }
+ );
+ $vbox->pack_start ($bbox, 0, 0, 0);
+ $vbox->add ($moz);
+ $w->fullscreen ();
+ #$w->set_default_size (640, 480);
+ $w->add ($vbox);
+ $w->signal_connect (destroy => sub {
+ Gtk2->main_quit;
+ return FALSE;
+ });
+ $w->show_all ();
+
+ $moz->load_url ($url);
+
+ Gtk2->main;
+
+ exit 0;
+}
+
+# Make the standard button bar across the top of the page.
+sub make_button_bar
+{
+ my $first = shift;
+ my $last = shift;
+ my $cb = shift;
+ my %params = @_;
+ my $bbox = Gtk2::Toolbar->new ();
+ $bbox->set_style ("GTK_TOOLBAR_TEXT");
+
+ my $i = 0;
+
+ my $bnext = Gtk2::ToolButton->new (undef, "Next slide");
+ $bnext->signal_connect (clicked => sub { &$cb ("NEXT") });
+ $bnext->set_sensitive (!$last);
+ $bbox->insert ($bnext, $i++);
+
+ my $bback = Gtk2::ToolButton->new (undef, "Back");
+ $bback->signal_connect (clicked => sub { &$cb ("PREV") });
+ $bback->set_sensitive (!$first);
+ $bbox->insert ($bback, $i++);
+
+ if (exists $params{restart}) {
+ $bbox->insert (Gtk2::SeparatorToolItem->new (), $i++);
+
+ my $brestart = Gtk2::ToolButton->new (undef, "Kill & restart");
+ $brestart->signal_connect (clicked => $params{restart});
+ $bbox->insert ($brestart, $i++);
+ }
+
+ my $sep = Gtk2::SeparatorToolItem->new ();
+ $sep->set_expand (TRUE);
+ $sep->set_draw (FALSE);
+ $bbox->insert ($sep, $i++);
+
+ my $optsmenu = Gtk2::Menu->new ();
+
+ my $bfirst = Gtk2::MenuItem->new ("First slide");
+ $bfirst->signal_connect (activate => sub { \&$cb ("FIRST") });
+ $bfirst->show ();
+ $optsmenu->append ($bfirst);
+
+ my $blast = Gtk2::MenuItem->new ("Last slide");
+ $blast->signal_connect (activate => sub { \&$cb ("LAST") });
+ $blast->show ();
+ $optsmenu->append ($blast);
+
+ my $slidesmenu = Gtk2::Menu->new ();
+ foreach (@files) {
+ my $item = Gtk2::MenuItem->new ($_->{name});
+ my $index = $_->{i};
+ $item->signal_connect (activate => sub { \&$cb ("I_$index") });
+ $item->set_sensitive ($current->{i} != $index);
+ $item->show ();
+ $slidesmenu->append ($item);
+ }
+
+ my $bslides = Gtk2::MenuItem->new ("Slides");
+ $bslides->set_submenu ($slidesmenu);
+ $bslides->show ();
+ $optsmenu->append ($bslides);
+
+ my $sep2 = Gtk2::SeparatorMenuItem->new ();
+ $sep2->show ();
+ $optsmenu->append ($sep2);
+
+ my $bscreenshot = Gtk2::MenuItem->new ("Take a screenshot");
+ $bscreenshot->signal_connect (activate => sub { screenshot () });
+ $bscreenshot->show ();
+ $optsmenu->append ($bscreenshot);
+
+ my $sep3 = Gtk2::SeparatorMenuItem->new ();
+ $sep3->show ();
+ $optsmenu->append ($sep3);
+
+ my $bquit = Gtk2::MenuItem->new ("Quit");
+ $bquit->signal_connect (activate => sub { \&$cb ("QUIT") });
+ $bquit->show ();
+ $optsmenu->append ($bquit);
+
+ my $boptions = Gtk2::MenuToolButton->new (undef, "Options");
+ #$boptions->signal_connect (clicked =>
+ # sub { $optsmenu->popup (undef, undef, undef, undef, ?, ?) } );
+ $bbox->insert ($boptions, $i++);
+ $boptions->set_menu ($optsmenu);
+
+ return $bbox;
+}
+
+# Try running the external "gnome-screenshot" program, if it's
+# available, else take a screenshot using gdk routines.
+sub screenshot
+{
+ system ("gnome-screenshot");
+
+ if ($? == -1) {
+ # We are going to save the entire screen.
+ my $root = Gtk2::Gdk->get_default_root_window ();
+ my ($width, $height) = $root->get_size;
+
+ # Create blank pixbuf to hold the image.
+ my $gdkpixbuf = Gtk2::Gdk::Pixbuf->new ('rgb',
+ 0, 8, $width, $height);
+
+ $gdkpixbuf->get_from_drawable ($root, $root->get_colormap (),
+ 0, 0, 0, 0, $width, $height);
+
+ my $i = 0;
+ $i++ while -f "screenshot$i.png";
+ $gdkpixbuf->save ("screenshot$i.png", 'png');
+ }
+
+ return FALSE;
+}
1;
+__END__
+
=head1 TUTORIAL
+=head2 START WRITING A TALK
+
+[Before you start writing your real talk, I urge you to read
+L</WHAT MAKES A GOOD TALK> below].
+
+To start your talk, all you have to do is to make a new directory
+somewhere:
+
+ mkdir talk
+ cd talk
+
+A tech talk consists of HTML files ("slides") and shell scripts. The
+filenames must start with a number, followed optionally by a
+description, followed by the extension (C<.html> or C<.sh>). So to
+start our talk with two slides:
+
+ echo "This is the introduction" > 0010-introduction.html
+ echo "This is the second slide" > 0020-second.html
+
+To run it, run the command from within the talk directory:
+
+ techtalk-pse
+
+Any other file in the directory is ignored, so if you want to add
+Makefiles, version control files etc, just go ahead.
+
+=head2 TIPS FOR WRITING HTML
+
+You may have your own techniques and tools for writing HTML, so
+this section is just to share my ideas. I start every
+HTML file with a standard stylesheet and Javascript header:
+
+ <link rel="stylesheet" href="style.css" type="text/css"/>
+ <script src="code.js" type="text/javascript"></script>
+
+That just ensures that I can put common styling instructions for all
+my slides in a single file (C<style.css>), and I have one place where
+I can add all Javascript, if I need to use any (C<code.js>).
+
+=head3 BACKGROUNDS, FONTS AND LOGOS
+
+To add a common background and font size to all slides, put this in
+C<style.css>:
+
+ body {
+ font-size: 24pt;
+ background: url(background-image.jpg) no-repeat;
+ }
+
+To add a logo in one corner:
+
+ body {
+ background: url(logo.jpg) top right no-repeat;
+ }
+
+=head3 SCALING AND CENTERING
+
+Scaling slide text and images so that they appear at the same
+proportionate size for any screen resolution can be done using
+Javascript. (See
+L<https://developer.mozilla.org/En/DOM/window.innerHeight>).
+
+If you want to center text horizontally, use CSS, eg:
+
+ p.center {
+ text-align: center;
+ }
+
+To center text vertically, CSS3 is supposed to offer a solution some
+time, but while you're waiting for that try
+L<http://www.w3.org/Style/Examples/007/center#vertical>.
+
+=head3 PREVIEWING HTML
+
+I find it helpful to have Firefox open to display the HTML files and
+styles as I edit them. Just start firefox in the talk directory:
+
+ firefox file://$(pwd) &
+
+When you edit an HTML file, click the Firefox reload button to
+immediately see your changes.
+
+Tech Talk PSE uses Mozilla embedding to display HTML, which uses the
+same Mozilla engine as Firefox, so what you should see in Firefox
+should be identical to what Tech Talk PSE displays.
+
+=head2 CREATING FIGURES
+
+Use your favorite tool to draw the figure, convert it to an image (in
+any format that the Mozilla engine can display) and include it using
+an C<E<lt>imgE<gt>> tag, eg:
+
+ <img src="fig1.gif">
+
+Suitable tools include: XFig, GnuPlot, GraphViz, and many TeX tools
+such as PicTex and in particular TikZ.
+
+=head2 EMBEDDING VIDEOS, ANIMATIONS, ETC.
+
+Using HTML 5, embedding videos in the browser is easy. See:
+L<https://developer.mozilla.org/En/Using_audio_and_video_in_Firefox>
+
+For animations, you could try L<Haxe|http://haxe.org/> which has a
+Javascript back-end. There are many other possibilities.
+
+If you are B<sure> that the venue will have an internet connection,
+why not embed a YouTube video.
+
+=head2 DISPLAYING EXISTING WEB PAGES
+
+Obviously you could just have an HTML file that contains a redirect to
+the public web page:
+
+ <meta http-equiv="Refresh" content="0; url=http://www.example.com/">
+
+However if you want your talk to work offline, then it's better to
+download the web page in advance, eg. using Firefox's "Save Page As
+-E<gt> Web Page, complete" feature, into the talk directory, then
+either rename or make a symbolic link to the slide name:
+
+ ln -s "haXe - Welcome to haXe.html" 0010-haxe-homepage.html
+
+=head2 TIPS FOR WRITING SHELL SCRIPTS
+
+Make sure each C<*.sh> file you write is executable, otherwise Tech
+Talk PSE won't be able to run it. (The program gives a warning if you
+forget this).
+
+A good idea is to start each script by sourcing some common functions.
+All my scripts start with:
+
+ #!/bin/bash -
+ source functions
+
+where C<functions> is another file (ignored by Tech Talk PSE) which
+contains common functions for setting shell history and starting a
+terminal.
+
+In C<functions>, I have:
+
+ # -*- shell-script -*-
+
+ # Place any local environment variables required in 'local'.
+ if [ -f local ]; then source local; fi
+
+ export PS1="$ "
+
+ export HISTFILE=$talkdir/history
+
+ rm -f $HISTFILE
+ touch $HISTFILE
+
+ add_history ()
+ {
+ echo "$@" >> $HISTFILE
+ }
+
+ terminal ()
+ {
+ # Make $HISTFILE unwritable so the shell won't update it
+ # when it exits.
+ chmod -w $HISTFILE
+
+ # Run gnome-terminal.
+ exec \
+ gnome-terminal \
+ --window \
+ --geometry=+100+100 \
+ --hide-menubar \
+ --disable-factory \
+ -e '/bin/bash --norc' \
+ "$@"
+ }
+
+By initializing the shell history, during your talk you can rapidly
+recall commands to start parts of the demonstration just by hitting
+the Up arrow. A complete shell script from one of my talks would look
+like this:
+
+ #!/bin/bash -
+ source functions
+ add_history guestfish -i debian.img
+ terminal --title="Examining a Debian guest image in guestfish"
+
+This is just a starting point for your own scripts. You may want to
+use a different terminal, such as xterm, and you may want to adjust
+terminal fonts.
+
=head1 REFERENCE
+=head2 ORDER OF FILES
+
+Tech Talk PSE displays the slides in the directory in lexicographic
+order (the same order as C<LANG=C ls -1>). Only files matching the
+following regexp are considered:
+
+ ^(\d+)(?:-.*)\.(html|sh)$
+
+For future compatibility, you should ensure that every slide has a
+unique numeric part (ie. I<don't> have C<0010-aaa.html> and
+C<0010-bbb.html>). This is because in future we want to have the
+ability to display multiple files side by side.
+
+Also for future compatibility, I<don't> use file names that have an
+uppercase letter immediately after the numeric part. This is because
+in future we want to allow placement hints using filenames like
+C<0010L-on-the-left.html> and C<0010R-on-the-right.html>.
+
+=head2 BASE URL AND CURRENT DIRECTORY
+
+The base URL is set to the be the directory containing the talk files.
+Thus you should use relative paths, eg:
+
+ <img src="fig1.gif">
+
+You can also place assets into subdirectories, because subdirectories
+are ignored by Tech Talk PSE, eg:
+
+ <img src="images/fig1.gif">
+
+When running shell scripts, the current directory is also set to be
+the directory containing the talk files, so the same rules about using
+relative paths apply there too.
+
+The environment variable C<$talkdir> is exported to scripts and it
+contains the absolute path of the directory containing the talk files.
+When a script is run, the current directory is the same as
+C<$talkdir>, but if your script changes directory (eg. into a
+subdirectory containing supporting files) then it can be useful to use
+C<$talkdir> to refer back to the original directory.
+
=head1 WHAT MAKES A GOOD TALK
+I like what Edward Tufte writes, for example his evisceration of
+PowerPoint use at NASA here:
+L<http://www.edwardtufte.com/bboard/q-and-a-fetch-msg?msg_id=0001yB>
+
+However it is sometimes hard to translate his ideas into clear
+presentations, and not all of that is the fault of the tools. Here
+are my thoughts and rules on how to deliver a good talk.
+
+B<First, most important rule:> Before you start drawing any slides at
+all, write your talk as a short essay.
+
+This is the number one mistake that presenters make, and it is partly
+a tool fault, because PowerPoint, OpenOffice, even Tech Talk PSE, all
+open up on an initial blank slide, inviting you to write a title and
+some bullet points. If you start that way, you will end up using the
+program as a kind of clumsy outlining tool, and then reading that
+outline to your audience. That's boring and a waste of time for you
+and your audience. (It would be quicker for them just to download the
+talk and read it at home).
+
+B<Secondly:> How long do you want to spend preparing the talk? A good
+talk, with a sound essay behind it, well thought out diagrams and
+figures, and interesting demonstrations, takes many hours to prepare.
+How many hours? I would suggest thinking about how many hours of
+effort your audience are putting in. Even just 20 people sitting
+there for half an hour is 10 man-hours of attention, and that is a
+very small talk, and doesn't include all the extra time and hassle
+that it took to get them all in one place.
+
+I don't think you can get away with spending less than two full days
+preparing a talk, if you want to master the topic and draw up accurate
+slides. Steve Jobs is reputed to spend weeks preparing his annual
+sales talk to the Apple faithful.
+
+B<Thirdly:> Now that you're going to write your talk as an essay, what
+should go in the slides? I would say that you should consider
+delivering the essay, I<not> the slides, to people who don't make the
+talk. An essay can be turned into an article or blog posting, whereas
+even "read-out-the-bullet-point" slides have a low information
+density, large size, and end-user compatibility problems (*.pptx
+anyone?).
+
+What, then, goes on the slides? Anything you cannot just say:
+diagrams, graphs, videos, animations, and of course (only with Tech
+Talk PSE!) demonstrations.
+
+B<Lastly:> Once you've got your talk as an essay and slides, practice,
+practice and practice again. Deliver the talk to yourself in the
+mirror, to your colleagues. Practice going backwards and forwards
+through the slides, using your actual laptop and the software so you
+know what to click and what keys to press. Partly memorize what you
+are going to say (but use short notes written on paper if you need
+to).
+
=head1 SEE ALSO
The Cognitive Style of PowerPoint, Tufte, Edward R.
git.annexia.org / techtalk-pse.git / blobdiff