[ViewVC] Annotation of: cvs/CV/bin/cv

#!/opt/bin/perl

use common::sense;

use Cwd ();
use Encode ();
use File::Glob ();
use Scalar::Util ();

use Gtk2 -init;
use Gtk2::Gdk::Keysyms;

use Gtk2::CV;

use Gtk2::CV::ImageWindow;
use Gtk2::CV::Schnauzer;

BEGIN {
   require Gtk2::CV::Plugin;
   require "$ENV{HOME}/.cvrc" if -r "$ENV{HOME}/.cvrc";
}

use Gtk2::CV::Plugin::NameCluster;
use Gtk2::CV::Plugin::RCluster;

Gtk2::CV::Jobber::start_slaves;

Gtk2::Rc->parse (Gtk2::CV::find_rcfile "gtkrc");

use File::Spec;

my $mainwin;
my $viewer;
my $viewer_count;
my $schnauzer;
my $info;
my $help;

my $schnauzer_idx = 0;

sub new_schnauzer {
   my $s = new Gtk2::CV::Schnauzer;

   $s->signal_connect_after (key_press_event => \&std_keys);
   $s->signal_connect (activate => sub {
      my $label = sprintf "%s (%d)",
                  (Glib::filename_display_name +(File::Spec->splitpath ($_[1]))[2]),
                  -s $_[1];
      $info->set_label ($label);
      $viewer->load_image ($_[1]) if $viewer; # TODO: error, or chose ANY viewer
   });

   Gtk2::CV::Plugin->call (new_schnauzer => $s);

   $s
}

our %VIEWER; # global viewer container so we can propagate signals

$SIG{USR1} = sub {
   # I assume glib calls us in a safe enough context to create an idle watcher
   add Glib::Idle sub {
      $_->reload for values %VIEWER;
      0
   };
};

sub new_viewer {
   my $self = new Gtk2::CV::ImageWindow;

   Scalar::Util::weaken ($VIEWER{$self+0} = $self);

   $viewer_count++;

   $self->set_title ("CV: Image");

   $self->signal_connect (key_press_event => sub {
      $viewer = $_[0];

      my $key = $_[1]->keyval;
      my $state = $_[1]->state;

      if ($state * "control-mask" && $key == $Gtk2::Gdk::Keysyms{c}) {
         my $viewer = new_viewer ();
         $viewer->set_image ($_[0]->{image});
         $viewer->show_all;
         1
      } else {
         &std_keys
            or $schnauzer->signal_emit (key_press_event => $_[1])
      }
   });
   $self->signal_connect (delete_event => sub { $_[0]->destroy; 0 });
   $self->signal_connect (destroy => sub {
      delete $VIEWER{$_[0]+0};
      $viewer = undef if $viewer == $_[0];

      main_quit Gtk2 unless --$viewer_count;

      0
   });

   $self->signal_connect (button3_press_event => sub {
      $mainwin->visible
         ? $mainwin->hide
         : $mainwin->show_all;

      1
   });

   Gtk2::CV::Plugin->call (new_imagewindow => $self);

   $self
}

sub std_keys {
   my $key = $_[1]->keyval;
   my $state = $_[1]->state;

   my $ctrl = $state * "control-mask";

   if ($key == $Gtk2::Gdk::Keysyms{q}) {
      $viewer->destroy;
   } elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{v}) {
      my $w = new Gtk2::Window;

      $w->set_role ("schnauzer");
      $w->set_title ("CV: Schnauzer");
      $w->add (my $s = new_schnauzer);
      $s->set_dir (File::Spec->curdir);
      $s->set_geometry_hints;
      $w->show_all;

   } elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{h}) {
      unless ($help) {
         require Gtk2::Ex::PodViewer;

         $help = new Gtk2::Window;
         $help->set_role ("help");
         $help->set_title ("CV: Help");
         $help->set_default_size (500, 300);
         $help->signal_connect (delete_event => sub { $help->hide; 1 });

         $help->add (my $sw = new Gtk2::ScrolledWindow);
         $sw->add (my $h = new Gtk2::Ex::PodViewer);

         #binmode DATA, ":utf8";
         $h->load_string (do { local $/; <DATA> });
      }

      $help->show_all;
   } else {
      return 0;
   }

   1
}

{
   $viewer = new_viewer;
   $::cur_viewer = $viewer;

   $schnauzer = new_schnauzer;

   $mainwin = new Gtk2::Window;
   $mainwin->set_role ("main");
   $mainwin->set_title ("CV");
   $mainwin->add (my $vbox = new Gtk2::VBox);
   $mainwin->signal_connect (delete_event => sub { $mainwin->hide; 1 });

   $vbox->add ($schnauzer);
   $vbox->pack_end (my $frame = new Gtk2::Frame, 0, 0, 0);
   $frame->add (my $hbox = new Gtk2::HBox 0, 0);
   $hbox->pack_start ((new Gtk2::Label "Info: "), 0, 0, 0);
   $hbox->pack_end   (my $labelwindow = new Gtk2::EventBox, 1, 1, 0);
   $labelwindow->add ($info = new Gtk2::Label);
   $labelwindow->signal_connect_after (size_request => sub { $_[1]->width (0); 0 });
   $info->set (selectable => 1, xalign => 0, justify => "left");

   $schnauzer->set_geometry_hints;
}

if (@ARGV) {
   my $show_first = sub {
      $schnauzer->show_all;
      $schnauzer->handle_key ($Gtk2::Gdk::Keysyms{space}, []);
      $viewer->show_all;
   };

   if (@ARGV == 1 && $ARGV[0] eq "-0r") {
      local $/;
      $schnauzer->set_paths ([split /\x00/, <STDIN>], 1, $show_first);
   } elsif (@ARGV == 1 && -d $ARGV[0]) {
      $schnauzer->set_dir (shift, $show_first);
   } else {
      if ($ARGV[0] eq "-g") {
         shift @ARGV;
         @ARGV = map +(File::Glob::bsd_glob $_, File::Glob::GLOB_BRACE | File::Glob::GLOB_QUOTE), @ARGV;
      }
      $schnauzer->set_paths ([@ARGV], 1, $show_first);
   }
} else {
   $schnauzer->set_dir (File::Spec->curdir, sub {
      $mainwin->show_all;
      $viewer->show_all;
   });
}

main Gtk2;

Gtk2::CV::flush_aio;

__DATA__

=encoding utf-8

=head1 NAME

cv - a fast gtk+ image viewer loosely modeled after XV

=head1 SYNOPSIS

   cv [file...]

=head1 FEATURES

CV is supposed to work similar to the venerable XV image viewer, just
faster. Why faster?

=over 4

=item * optimized directory scanning algorithm

The directory scanning in CV uses some tricks that - on most modern
filesystems - makes it possible to detect filetypes faster than stat()'ing
every file. This makes CV suitable for directories with lots of files
(10000+).

This algorithm is quite unprecise - it doesn't make a difference between
files, device nodes, symlinks and the like, and filetype detection is done
using the file extension only.

On the positive side, it is usually many orders of magnitude faster than
traditional scanning techniques (good for directories with 10000 or
100000+ files).

=item * queuing for all time-consuming background tasks

All tasks, such as unlinking files or generating thumbnails, that can be
done in the background will be done so - no waiting required, even when
changing directories.

=item * use of asynchronous I/O

CV tries to use asynchronous I/O whereever it makes sense, for example
while scanning directories, waiting for stat data, unlinking files or
generating thumbnails. This usually decreases scanning times for large
directories a bit (especially on RAID devices and over NFS) and makes CV
much more interactive.

=item * fast image loading

The time span between the user issuing a command and displaying the new
image should be as small as possible. CV uses optimized (especially
for JPEG) loading functions and sacrifices some quality (e.g no gamma
correction, although this might change) to achieve this speed.

=item * fast thumbnail creation

Thumbnail creation uses both CPU and Disk-I/O. CV interleaves both, so
on modern CPUs, thumbnailing is usually limited by I/O speed. Thumbnail
creation for JPEGs has been specially optimized and can even take
advantage of multiple CPUs.

=item * minimum optical clutter

CV has no menus or other user interface elements that take up a lot of
screen space (or are useful for beginning users). The schnauzer windows
can also be somewhat crowded.

The point of an image viewer is viewing images, not a nice GUI. This is
similar to XV's behaviour.

=item * efficient (and hard to learn) user interface

CV uses key combinations. A lot. If you are an experienced XV user, you
will find most of these keys familiar. If not, CV might be hard to use at
first, but will be an efficient tool later.

=item * multi-window GUI

CV doesn't force you to use a specific layout, instead it relies on your
window manager, thus enabling you to chose whatever layout that suits you
most.

=item * i18n'ed filename handling throughout

As long as glib can recognize your filename encoding (either UTF-8 or
locale-specific, depending on the setting of G_BROKEN_FILENAMES) and you
have the relevant fonts, CV will display your filenames correctly.

=item * extensible through plug-ins

I have weird plug-ins that access remote databases to find a
directory. This is not likely to be of any use to other people. Likewise,
others might have weird requirements I cannot dream of.

=item * filename clustering

Among the standard plug-ins is a filename clustering plug-in, that (in
case of tens of thousands images in one directory) might be able to
cluster similar names together.

=back

=head1 DESCRIPTION

=head2 THE IMAGE WINDOW

You can use the following keys in the image window:

 q            quit the program
 <            half the image size
 >            double the image size
 ,            shrink the image by 10%
 .            enlarge the image by 10%
 n            reset to normal size
 m            maximize to screensize
 M            maximize to screensize, respecting image aspect
 ctrl-m       toggle maxpect-always mode
 ctrl-sift-m  toggle using current image size as max image size
 u            uncrop
 r            set scaling mode to 'nearest' (fastest)
 s            set scaling mode to 'bilinear' (default)
 shift-s      set scaling mode to 'hyper' (slowest)
 t            rotate clockwise 90°
 T            rotate counterclockwise°
 a            apply all rotations loslessly to a jpeg file (using exiftran)
 ctrl-v       open a new visual schnauzer window for the current dir
 ctrl-c       clone the current image window
 ctrl-e       run an editor ($CV_EDITOR or "gimp") on the current image
 ctrl-p       fire up the print dialog
 escape       cancel a crop action

And when playing movies, these additional keys are active:

 left         rewind by 10 seconds
 right        forward by 10 seconds
 down         rewind by 60 seconds
 up           forward by 60 seconds
 pg_up        rewind by 600 seconds
 pg_down      forward by 600 seconds
 o            toggle on-screen display
 p            pause/unpause
 escape       stop playing
 9            turn volume down
 0            turn volume up

Any other keys will be sent to the default schnauzer window, which can be
toggled on and off by right-clicking into the image window.

Left-clicking into the image window will let you crop the image (usually
to zoom into large images that CV scales down).

=head2 THE VISUAL SCHNAUZER

Any image-loading action in a schnauzer window acts on the
"last-recently-activated" imagewindow, which currently is simply the last
image window that received a keypress.

You can use the following keys in the schnauzer window:

 ctrl-space,
 space        move to and display next image
 ctrl-backspace,
 backspace    move to and display previous image
 ctrl-return,
 return       display selected picture, or enter directory

 cursor keys  move selection
 page-up      move one page up
 page-down    move one page down
 home         move to first file
 end          move to last file

 ctrl-a       select all files
 ctrl-shift-a select all files currently displayed in the schnauzer window
 ctrl-d       delete selected files WITHOUT ASKING AGAIN
 ctrl-g       force generation of thumbnais for the selected files
 ctrl-s       rescan current direcory or files updates/deletes etc.
 ctrl-u       update selected (or all) icons if neccessary
 ctrl--       unselected thumbnailed images
 ctrl-+       keep only thumbnailed images, deselect others

 ^            go to parent directory (caret).

 0-9,
 a-z          find the first filename beginning with this letter

Right-clicking into the schnauzer window displays a pop-up menu with
additional actions.

=head3 SELECTION

You can select entries in the Schnauzer in a variety of ways:

=over 4

=item Keyboard

Moving the cursor with the keyboard will first deselect all files and then
select the file you moved to.

=item Clicking

Clicking on an entry will select the one you clicked and deselect all
others.

=item Shift-Clicking

Shift-clicking will toggle the selection on the entry under the mouse.

=item Dragging

Dragging will select all entries between the one selected when pushing the
button and the one selected when releasing the button. If you move above
or below the schnauzer area while drag-selecting, the schnauzer will move
up/down one row twice per second. In addition, horizontal mouse movement
acts as a kind of invisible horizontal scrollbar.

=item Hint: double-click works while click-selecting

You can double-click any image while click-selecting to display it
without stopping the selection process. This will act as if you normally
double-clicked the image to display it, and will toggle the selection
twice, resulting in no change.

=back

=head1 FILES

When starting, CV runs the F<.cvrc> file in your F<$HOME> directory as if
it were a perl script. in that, you will mostly load plug-ins.

Example:

   system "fping -q -t 10 ether"
     or require "/fs/cv/cvplugin.pl";

This will load a plug-in, but only if the machine I<ether> is reachable
(supposedly the plug-in is networked in some way :).

=head1 ENVIRONMENT VARIABLES

=over 4

=item CV_EDITOR

The program that gets executed when the user presses C<CTRL-e> in the
Schnauzer or image window. The default is C<gimp>.

=item CV_AUDIO_PLAYER

Program used to play all sorts of audio (wav, aif, mp3, ogg...), default "play".
Will be called like C<< $CV_AUDIO_PLAYER -- <path> >>.

=item CV_PRINT_DESTINATION

The default (perl-style) destination to use in the print dialog.

=item CV_TRASHCAN

When set, must point to a directory where all files that are deleted by
the "Delete Physically" (ctrl-d) action are moved to (other deletion
actions still delete!). If unset, files that are deleted are really being
deleted.

=back

=head1 SIGNALS

Sending CV a SIGUSR1 signal will cause all image viewers to reload the
currently loaded image. This is useful if you use CV as a viewer for
changing data - just run it in the background with some path and each time
the image changes, send it a SIGUSR1.

=head1 SECURITY CONSIDERATIONS

CV uses Pixbuf to load non-JPEG images. Pixbuf is not considered safe for
this purpose, though (from the gtk-2.2 release notes):

"While efforts have been made to make gdk-pixbuf robust against invalid
images, using gdk-pixbuf to load untrusted data is not recommended, due to
the likelyhood that there are additional problems where an invalid image
could cause gdk-pixbuf to crash or worse."

=head1 BUGS/TODO

 Lots of functionality is missing.

 Pixbuf doesn't always honor G_BROKEN_FILENAMES, so accessing files with
 names incompatible with utf-8 might fail.

 rotate on disk
 lots of ui issues
 save(?)
 preferences

=head1 AUTHOR

Marc Lehmann <cv@plan9.de>.

=cut

Revision:	1.80
Committed:	Mon Nov 30 20:13:49 2009 UTC (14 years, 6 months ago) by root
Branch:	MAIN
Changes since 1.79:	+2 -0 lines
Log Message:	common::sense
#	User	Rev	Content
1	root	1.1	#!/opt/bin/perl
2
3	root	1.80	use common::sense;
4
5	root	1.37	use Cwd ();
6			use Encode ();
7	root	1.72	use File::Glob ();
8	root	1.79	use Scalar::Util ();
9	root	1.37
10	root	1.12	use Gtk2 -init;
11			use Gtk2::Gdk::Keysyms;
12
13	root	1.48	use Gtk2::CV;
14
15	root	1.12	use Gtk2::CV::ImageWindow;
16			use Gtk2::CV::Schnauzer;
17
18	root	1.48	BEGIN {
19			require Gtk2::CV::Plugin;
20			require "$ENV{HOME}/.cvrc" if -r "$ENV{HOME}/.cvrc";
21			}
22
23			use Gtk2::CV::Plugin::NameCluster;
24			use Gtk2::CV::Plugin::RCluster;
25	root	1.16
26	root	1.77	Gtk2::CV::Jobber::start_slaves;
27
28	root	1.16	Gtk2::Rc->parse (Gtk2::CV::find_rcfile "gtkrc");
29
30	root	1.20	use File::Spec;
31
32			my $mainwin;
33	root	1.12	my $viewer;
34	root	1.62	my $viewer_count;
35	root	1.12	my $schnauzer;
36	root	1.20	my $info;
37	root	1.21	my $help;
38	root	1.12
39	root	1.25	my $schnauzer_idx = 0;
40
41	root	1.12	sub new_schnauzer {
42	root	1.20	my $s = new Gtk2::CV::Schnauzer;
43	root	1.12
44			$s->signal_connect_after (key_press_event => \&std_keys);
45	root	1.20	$s->signal_connect (activate => sub {
46			my $label = sprintf "%s (%d)",
47	root	1.75	(Glib::filename_display_name +(File::Spec->splitpath ($_[1]))[2]),
48	root	1.20	-s $_[1];
49			$info->set_label ($label);
50	root	1.62	$viewer->load_image ($_[1]) if $viewer; # TODO: error, or chose ANY viewer
51	root	1.20	});
52	root	1.12
53	root	1.40	Gtk2::CV::Plugin->call (new_schnauzer => $s);
54
55	root	1.53	$s
56	root	1.12	}
57
58	root	1.79	our %VIEWER; # global viewer container so we can propagate signals
59
60			$SIG{USR1} = sub {
61			# I assume glib calls us in a safe enough context to create an idle watcher
62			add Glib::Idle sub {
63			$_->reload for values %VIEWER;
64			0
65			};
66			};
67
68	root	1.62	sub new_viewer {
69			my $self = new Gtk2::CV::ImageWindow;
70
71	root	1.79	Scalar::Util::weaken ($VIEWER{$self+0} = $self);
72
73	root	1.62	$viewer_count++;
74
75			$self->set_title ("CV: Image");
76
77			$self->signal_connect (key_press_event => sub {
78			$viewer = $_[0];
79
80			my $key = $_[1]->keyval;
81			my $state = $_[1]->state;
82
83			if ($state * "control-mask" && $key == $Gtk2::Gdk::Keysyms{c}) {
84			my $viewer = new_viewer ();
85			$viewer->set_image ($_[0]->{image});
86			$viewer->show_all;
87			1
88			} else {
89			&std_keys
90			or $schnauzer->signal_emit (key_press_event => $_[1])
91			}
92			});
93	root	1.63	$self->signal_connect (delete_event => sub { $_[0]->destroy; 0 });
94	root	1.62	$self->signal_connect (destroy => sub {
95	root	1.79	delete $VIEWER{$_[0]+0};
96	root	1.62	$viewer = undef if $viewer == $_[0];
97
98			main_quit Gtk2 unless --$viewer_count;
99	root	1.63
100			0
101	root	1.62	});
102
103			$self->signal_connect (button3_press_event => sub {
104			$mainwin->visible
105			? $mainwin->hide
106			: $mainwin->show_all;
107	root	1.63
108	root	1.62	1
109			});
110
111			Gtk2::CV::Plugin->call (new_imagewindow => $self);
112
113			$self
114			}
115
116	root	1.12	sub std_keys {
117			my $key = $_[1]->keyval;
118			my $state = $_[1]->state;
119
120	root	1.21	my $ctrl = $state * "control-mask";
121	root	1.12
122			if ($key == $Gtk2::Gdk::Keysyms{q}) {
123	root	1.62	$viewer->destroy;
124	root	1.12	} elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{v}) {
125	root	1.20	my $w = new Gtk2::Window;
126	root	1.26
127	root	1.66	$w->set_role ("schnauzer");
128	root	1.26	$w->set_title ("CV: Schnauzer");
129	root	1.20	$w->add (my $s = new_schnauzer);
130			$s->set_dir (File::Spec->curdir);
131	root	1.25	$s->set_geometry_hints;
132	root	1.21	$w->show_all;
133	root	1.25
134	root	1.21	} elsif ($ctrl && $key == $Gtk2::Gdk::Keysyms{h}) {
135			unless ($help) {
136	root	1.73	require Gtk2::Ex::PodViewer;
137	root	1.21
138			$help = new Gtk2::Window;
139	root	1.67	$help->set_role ("help");
140	root	1.26	$help->set_title ("CV: Help");
141	root	1.21	$help->set_default_size (500, 300);
142			$help->signal_connect (delete_event => sub { $help->hide; 1 });
143
144			$help->add (my $sw = new Gtk2::ScrolledWindow);
145	root	1.73	$sw->add (my $h = new Gtk2::Ex::PodViewer);
146	root	1.21
147			#binmode DATA, ":utf8";
148			$h->load_string (do { local $/; <DATA> });
149			}
150
151			$help->show_all;
152	root	1.12	} else {
153	root	1.43	return 0;
154	root	1.12	}
155
156	root	1.43	1
157	root	1.12	}
158
159	root	1.20	{
160	root	1.62	$viewer = new_viewer;
161			$::cur_viewer = $viewer;
162	root	1.40
163	root	1.20	$schnauzer = new_schnauzer;
164
165			$mainwin = new Gtk2::Window;
166	root	1.66	$mainwin->set_role ("main");
167	root	1.20	$mainwin->set_title ("CV");
168			$mainwin->add (my $vbox = new Gtk2::VBox);
169	root	1.53	$mainwin->signal_connect (delete_event => sub { $mainwin->hide; 1 });
170	root	1.20
171			$vbox->add ($schnauzer);
172	root	1.22	$vbox->pack_end (my $frame = new Gtk2::Frame, 0, 0, 0);
173	root	1.20	$frame->add (my $hbox = new Gtk2::HBox 0, 0);
174	root	1.45	$hbox->pack_start ((new Gtk2::Label "Info: "), 0, 0, 0);
175			$hbox->pack_end (my $labelwindow = new Gtk2::EventBox, 1, 1, 0);
176			$labelwindow->add ($info = new Gtk2::Label);
177			$labelwindow->signal_connect_after (size_request => sub { $_[1]->width (0); 0 });
178			$info->set (selectable => 1, xalign => 0, justify => "left");
179	root	1.25
180			$schnauzer->set_geometry_hints;
181	root	1.20	}
182	root	1.12
183			if (@ARGV) {
184	root	1.68	my $show_first = sub {
185			$schnauzer->show_all;
186			$schnauzer->handle_key ($Gtk2::Gdk::Keysyms{space}, []);
187			$viewer->show_all;
188			};
189
190	root	1.71	if (@ARGV == 1 && $ARGV[0] eq "-0r") {
191			local $/;
192	root	1.74	$schnauzer->set_paths ([split /\x00/, <STDIN>], 1, $show_first);
193	root	1.71	} elsif (@ARGV == 1 && -d $ARGV[0]) {
194	root	1.74	$schnauzer->set_dir (shift, $show_first);
195	root	1.71	} else {
196	root	1.72	if ($ARGV[0] eq "-g") {
197			shift @ARGV;
198			@ARGV = map +(File::Glob::bsd_glob $_, File::Glob::GLOB_BRACE \| File::Glob::GLOB_QUOTE), @ARGV;
199			}
200	root	1.74	$schnauzer->set_paths ([@ARGV], 1, $show_first);
201	root	1.71	}
202	root	1.17	} else {
203	root	1.68	$schnauzer->set_dir (File::Spec->curdir, sub {
204			$mainwin->show_all;
205			$viewer->show_all;
206			});
207	root	1.12	}
208
209			main Gtk2;
210	root	1.21
211	root	1.69	Gtk2::CV::flush_aio;
212
213	root	1.21	__DATA__
214	root	1.12
215	root	1.58	=encoding utf-8
216
217	root	1.11	=head1 NAME
218
219	root	1.47	cv - a fast gtk+ image viewer loosely modeled after XV
220	root	1.11
221			=head1 SYNOPSIS
222
223			cv [file...]
224
225	root	1.47	=head1 FEATURES
226
227			CV is supposed to work similar to the venerable XV image viewer, just
228			faster. Why faster?
229
230			=over 4
231
232			=item * optimized directory scanning algorithm
233
234	root	1.55	The directory scanning in CV uses some tricks that - on most modern
235	root	1.47	filesystems - makes it possible to detect filetypes faster than stat()'ing
236			every file. This makes CV suitable for directories with lots of files
237			(10000+).
238
239			This algorithm is quite unprecise - it doesn't make a difference between
240			files, device nodes, symlinks and the like, and filetype detection is done
241			using the file extension only.
242
243	root	1.55	On the positive side, it is usually many orders of magnitude faster than
244			traditional scanning techniques (good for directories with 10000 or
245			100000+ files).
246
247	root	1.53	=item * queuing for all time-consuming background tasks
248
249			All tasks, such as unlinking files or generating thumbnails, that can be
250			done in the background will be done so - no waiting required, even when
251			changing directories.
252
253	root	1.47	=item * use of asynchronous I/O
254
255			CV tries to use asynchronous I/O whereever it makes sense, for example
256	root	1.53	while scanning directories, waiting for stat data, unlinking files or
257			generating thumbnails. This usually decreases scanning times for large
258			directories a bit (especially on RAID devices and over NFS) and makes CV
259			much more interactive.
260	root	1.47
261			=item * fast image loading
262
263			The time span between the user issuing a command and displaying the new
264			image should be as small as possible. CV uses optimized (especially
265			for JPEG) loading functions and sacrifices some quality (e.g no gamma
266	root	1.55	correction, although this might change) to achieve this speed.
267	root	1.47
268			=item * fast thumbnail creation
269
270	root	1.55	Thumbnail creation uses both CPU and Disk-I/O. CV interleaves both, so
271			on modern CPUs, thumbnailing is usually limited by I/O speed. Thumbnail
272			creation for JPEGs has been specially optimized and can even take
273			advantage of multiple CPUs.
274	root	1.47
275			=item * minimum optical clutter
276
277			CV has no menus or other user interface elements that take up a lot of
278	root	1.55	screen space (or are useful for beginning users). The schnauzer windows
279			can also be somewhat crowded.
280	root	1.47
281			The point of an image viewer is viewing images, not a nice GUI. This is
282			similar to XV's behaviour.
283
284			=item * efficient (and hard to learn) user interface
285
286			CV uses key combinations. A lot. If you are an experienced XV user, you
287			will find most of these keys familiar. If not, CV might be hard to use at
288			first, but will be an efficient tool later.
289
290	root	1.55	=item * multi-window GUI
291
292			CV doesn't force you to use a specific layout, instead it relies on your
293			window manager, thus enabling you to chose whatever layout that suits you
294			most.
295
296	root	1.47	=item * i18n'ed filename handling throughout
297
298			As long as glib can recognize your filename encoding (either UTF-8 or
299	root	1.55	locale-specific, depending on the setting of G_BROKEN_FILENAMES) and you
300			have the relevant fonts, CV will display your filenames correctly.
301	root	1.47
302			=item * extensible through plug-ins
303
304			I have weird plug-ins that access remote databases to find a
305			directory. This is not likely to be of any use to other people. Likewise,
306			others might have weird requirements I cannot dream of.
307
308			=item * filename clustering
309
310			Among the standard plug-ins is a filename clustering plug-in, that (in
311			case of tens of thousands images in one directory) might be able to
312			cluster similar names together.
313
314			=back
315
316	root	1.11	=head1 DESCRIPTION
317
318			=head2 THE IMAGE WINDOW
319
320			You can use the following keys in the image window:
321
322	root	1.50	q quit the program
323			< half the image size
324			> double the image size
325			, shrink the image by 10%
326			. enlarge the image by 10%
327			n reset to normal size
328			m maximize to screensize
329			M maximize to screensize, respecting image aspect
330			ctrl-m toggle maxpect-always mode
331	root	1.59	ctrl-sift-m toggle using current image size as max image size
332	root	1.50	u uncrop
333			r set scaling mode to 'nearest' (fastest)
334			s set scaling mode to 'bilinear' (default)
335			shift-s set scaling mode to 'hyper' (slowest)
336			t rotate clockwise 90°
337			T rotate counterclockwise°
338	root	1.64	a apply all rotations loslessly to a jpeg file (using exiftran)
339	root	1.50	ctrl-v open a new visual schnauzer window for the current dir
340	root	1.63	ctrl-c clone the current image window
341	root	1.50	ctrl-e run an editor ($CV_EDITOR or "gimp") on the current image
342	root	1.57	ctrl-p fire up the print dialog
343	root	1.50	escape cancel a crop action
344	root	1.11
345	root	1.33	And when playing movies, these additional keys are active:
346
347	root	1.50	left rewind by 10 seconds
348			right forward by 10 seconds
349			down rewind by 60 seconds
350			up forward by 60 seconds
351			pg_up rewind by 600 seconds
352			pg_down forward by 600 seconds
353			o toggle on-screen display
354			p pause/unpause
355			escape stop playing
356			9 turn volume down
357			0 turn volume up
358	root	1.33
359	root	1.47	Any other keys will be sent to the default schnauzer window, which can be
360			toggled on and off by right-clicking into the image window.
361	root	1.11
362	root	1.47	Left-clicking into the image window will let you crop the image (usually
363			to zoom into large images that CV scales down).
364	root	1.11
365			=head2 THE VISUAL SCHNAUZER
366
367	root	1.63	Any image-loading action in a schnauzer window acts on the
368			"last-recently-activated" imagewindow, which currently is simply the last
369			image window that received a keypress.
370
371	root	1.11	You can use the following keys in the schnauzer window:
372
373	root	1.47	ctrl-space,
374	root	1.50	space move to and display next image
375	root	1.47	ctrl-backspace,
376	root	1.50	backspace move to and display previous image
377	root	1.47	ctrl-return,
378	root	1.50	return display selected picture, or enter directory
379	root	1.11
380	root	1.50	cursor keys move selection
381			page-up move one page up
382			page-down move one page down
383			home move to first file
384			end move to last file
385
386			ctrl-a select all files
387			ctrl-shift-a select all files currently displayed in the schnauzer window
388			ctrl-d delete selected files WITHOUT ASKING AGAIN
389			ctrl-g force generation of thumbnais for the selected files
390			ctrl-s rescan current direcory or files updates/deletes etc.
391			ctrl-u update selected (or all) icons if neccessary
392	root	1.76	ctrl-- unselected thumbnailed images
393			ctrl-+ keep only thumbnailed images, deselect others
394	root	1.47
395	root	1.56	^ go to parent directory (caret).
396
397	root	1.47	0-9,
398	root	1.50	a-z find the first filename beginning with this letter
399	root	1.47
400			Right-clicking into the schnauzer window displays a pop-up menu with
401			additional actions.
402
403	root	1.60	=head3 SELECTION
404
405			You can select entries in the Schnauzer in a variety of ways:
406
407			=over 4
408
409			=item Keyboard
410
411			Moving the cursor with the keyboard will first deselect all files and then
412			select the file you moved to.
413
414	root	1.61	=item Clicking
415	root	1.60
416	root	1.61	Clicking on an entry will select the one you clicked and deselect all
417			others.
418	root	1.60
419	root	1.61	=item Shift-Clicking
420
421			Shift-clicking will toggle the selection on the entry under the mouse.
422
423			=item Dragging
424	root	1.60
425			Dragging will select all entries between the one selected when pushing the
426			button and the one selected when releasing the button. If you move above
427			or below the schnauzer area while drag-selecting, the schnauzer will move
428			up/down one row twice per second. In addition, horizontal mouse movement
429			acts as a kind of invisible horizontal scrollbar.
430
431			=item Hint: double-click works while click-selecting
432
433			You can double-click any image while click-selecting to display it
434			without stopping the selection process. This will act as if you normally
435			double-clicked the image to display it, and will toggle the selection
436			twice, resulting in no change.
437
438			=back
439
440	root	1.47	=head1 FILES
441
442			When starting, CV runs the F<.cvrc> file in your F<$HOME> directory as if
443			it were a perl script. in that, you will mostly load plug-ins.
444
445			Example:
446
447			system "fping -q -t 10 ether"
448			or require "/fs/cv/cvplugin.pl";
449
450			This will load a plug-in, but only if the machine I<ether> is reachable
451			(supposedly the plug-in is networked in some way :).
452	root	1.11
453	root	1.79	=head1 ENVIRONMENT VARIABLES
454	root	1.27
455			=over 4
456
457	root	1.38	=item CV_EDITOR
458
459			The program that gets executed when the user presses C<CTRL-e> in the
460			Schnauzer or image window. The default is C<gimp>.
461
462	root	1.70	=item CV_AUDIO_PLAYER
463
464			Program used to play all sorts of audio (wav, aif, mp3, ogg...), default "play".
465			Will be called like C<< $CV_AUDIO_PLAYER -- <path> >>.
466
467	root	1.27	=item CV_PRINT_DESTINATION
468
469			The default (perl-style) destination to use in the print dialog.
470
471	root	1.38	=item CV_TRASHCAN
472
473	root	1.78	When set, must point to a directory where all files that are deleted by
474			the "Delete Physically" (ctrl-d) action are moved to (other deletion
475			actions still delete!). If unset, files that are deleted are really being
476			deleted.
477	root	1.38
478	root	1.27	=back
479
480	root	1.79	=head1 SIGNALS
481
482			Sending CV a SIGUSR1 signal will cause all image viewers to reload the
483			currently loaded image. This is useful if you use CV as a viewer for
484			changing data - just run it in the background with some path and each time
485			the image changes, send it a SIGUSR1.
486
487	root	1.23	=head1 SECURITY CONSIDERATIONS
488
489	root	1.54	CV uses Pixbuf to load non-JPEG images. Pixbuf is not considered safe for
490			this purpose, though (from the gtk-2.2 release notes):
491	root	1.23
492			"While efforts have been made to make gdk-pixbuf robust against invalid
493			images, using gdk-pixbuf to load untrusted data is not recommended, due to
494			the likelyhood that there are additional problems where an invalid image
495			could cause gdk-pixbuf to crash or worse."
496
497	root	1.11	=head1 BUGS/TODO
498	root	1.23
499	root	1.47	Lots of functionality is missing.
500
501			Pixbuf doesn't always honor G_BROKEN_FILENAMES, so accessing files with
502	root	1.54	names incompatible with utf-8 might fail.
503	root	1.11
504			rotate on disk
505			lots of ui issues
506			save(?)
507			preferences
508
509			=head1 AUTHOR
510
511			Marc Lehmann <cv@plan9.de>.
512
513			=cut
514	root	1.1