katarakt - a simple PDF viewer with three layouts
katarakt ([OPTIONS] FILE|(-u URL))*
It’s a PDF viewer. It views PDFs.
There are currently three layouts. The single layout is
very simple and only supports scrolling on a per page basis. As the name
suggests the current page is displayed in the center and zoomed to fit the
window. It is active by default.
The grid layout is much more advanced and offers continuous
(smooth, per pixel) scrolling, zooming and adjusting the column count. Pages
keep their correct relative size and are shown in a grid.
The presenter layout is for giving a presentation. It opens
a second window, to be viewed on the projector, and shows the current and
next slide in the main window.
For every file passed on the command line a separate process is
spawned.
-u, --url
Instead of opening a local document, download it from the
given URL.
-p, --page NUM
Start on page NUM.
-f, --fullscreen
Start in fullscreen mode.
-q, --quit true|false
If true, quit on initialization failure. If false, show
the window even if an error occured. Overrides the config option
quit_on_init_fail.
-s, --single-instance true|false
If true, prevents opening the same document twice and
focuses the existing instance. Overrides the config option
single_instance_per_file.
--write-default-config FILE
Write the built-in default configuration to FILE
and exit. Hint: on unix systems, you can use --write-defaults
/dev/stdout to print the defaults.
-v, --version
Print version information and exit.
-h, --help
Print help and exit.
Variables and key bindings can be changed by modifying the katarakt.ini file. By
default it is read from $XDG_CONFIG_HOME.
Variables must be listed under the section "[Settings]",
keys under section "[Keys]". Settings that are not present in the
config file use the built-in default. For a list of all variables with a
short explanation see below.
q
Quit katarakt.
1
Switch to single layout. Views a single page at a
time, scaled to fit the screen.
2
Switch to grid layout. Views pages in a continuous
fashion, scaled to fit the window width. Supports zooming and multiple
columns.
3
Switch to presenter layout. Views the current page
and a smaller preview of the next page. Also, opens a second window that shows
only the current page for displaying on a projector.
Up, Down, Left, Right, k,
j, h, l
Move around (up/down/left/right).
^u, ^d
Scroll up/down half the screen.
BackSpace, Space, ^b, ^f
Scroll up/down the screen. By default scrolls 90% to
create an overlapping region.
PgUp, PgDown
Scroll up/down one page. Kind of swaps the pages in
place.
Home, End, g, G
Go to the first/last page.
^g
Show goto page bar.
/
Show the search bar. Hitting Esc will hide the
results, searching for an empty string will clear them. If the search term
contains an uppercase letter the search is case sensitive
("smartcase"). If you search for the same term twice the next hit
starting from the current view is selected.
?
Show the search bar. This next search will be
backwards.
n, N
Focus next/previous search hit. This does not take the
current view into account. For finding the next hit around the current view
search for the same term again.
^n, ^N
Focus next/previous search hit that is currently not
visible.
^o, ^i, Alt-Left, Alt-Right
Move backward/forward through the jump list. Entries are
added automatically when jumping.
m
Manually add the current page to the jump list.
-, +, =
Adjust zoom level (grid layout only).
z
Reset zoom level to default, i.e. fit width (grid
layout only).
[, ]
Adjust column count (grid layout only).
{, }
Adjust the column the first page will be displayed in.
Useful for reading in a book layout with a cover page (grid layout
only).
,, .
Rotate pages left/right.
t
Toggle the page number display in the bottom right
corner.
i
Toggle between normal and inverted color rendering.
^c
Copy the current selection to the global clipboard.
v
Swap the mouse buttons for selection and panning. The the
left mouse button’s current operation is indicated by the mouse
cursor.
f
Toggle fullscreen.
r
Reload the document. This can also be achieved by sending
SIGUSR1 to the process. katarakt reloads automatically if the opened
file has changed.
o
Open a different document; shows a file dialog.
s
Show a file dialog to save the current document.
F9
Toggle the table of contents.
x
Toggle freezing the slide currently displayed in the
projector window. When frozen, scrolling only affects the main window.
string default_layout
single: The layout on startup. Possible values:
single, grid, presenter.
string background_color
0xDF202020: Background color in ARGB Format. Alpha only
works when using a compositor.
string background_color_fullscreen
0xFF000000: Fullscreen background color in ARGB
Format.
string unrendered_page_color
0x40FFFFFF: Color that gets drawn instead of a page that
hasn’t been rendered yet. If colors are inverted, this gets inverted as
well.
int click_link_button
1: The mouse button used for clicking links. Buttons 1-5
are supported.
int drag_view_button
2: The mouse button used for scrolling the view.
Double-clicking this button centers the view around the location of the click.
This is especially useful when using many columns to get an overview. Resets
the column count to 1.
int select_text_button
1: The mouse button used for text selection. Double- and
triple-clicking are supported to select with word/line granularity.
int hide_mouse_timeout
2000: The delay in milliseconds after which the mouse
cursor is hidden. Set to 0 to disable.
int smooth_scroll_delta
30: Pixel offset when moving around.
float screen_scroll_factor
0.9: Factor for scrolling the screen. Should be <= 1
to create an overlapping region.
float jump_padding
0.2: Distance from the border of the screen to keep for
jump targets, e.g. search hits. Moves the view so that search hits are
centered more.
int rect_margin
2: Number of pixels search rects are expanded by.
int useless_gap
2: Gap between two pages in grid layout in
pixels.
int min_zoom
-14: Smallest zoom value.
int max_zoom
30: Biggest zoom value.
float zoom_factor
0.05: Influences the number of steps between min and
max.
int min_page_width
50: Pages can not be smaller than this.
bool quit_on_init_fail
false: If true, quit katarakt if the document fails to
open.
bool single_instance_per_file
false: If set and katarakt is called with a file that is
already shown in another katarakt instance, then the other katarakt window is
activated instead.
string stylesheet
See http://doc.qt.io/qt-4.8/stylesheet.html. It can be
overridden via Qt’s
-stylesheet command line option. The
following example changes the
goto page bar:
stylesheet="
GotoLine {
margin: 0px;
padding: 4px;
border-top-right-radius: 6px;
border-top: 1px solid black;
border-right: 1px solid black;
}"
string page_overlay_text
Page %1/%2: The text in the bottom right corner.
string icon_theme
The name of your icon theme. Fill in if auto detection
fails.
int prefetch_count
4: Number of pages exceeding the currently visible ones
to render, back- and forwards respectively.
float inverted_color_contrast
0.5: the contrast when using inverted colors to avoid too
much brightness.
float inverted_color_brightening
0.15: amount of brightening when using inverted colors to
shift black to gray.
int mouse_wheel_factor
120: QT delta for turning the mouse wheel 1 click.
Shouldn’t need to be touched.
bool thumbnail_filter
true: Enables the higher quality downsampling filter for
thumbnails.
int thumbnail_size
32: One dimension of square thumbnails saved at run-time
for every page that was once rendered.
Feel free to join the IRC channel #katarakt on freenode.
katarakt is written by Philipp Erhardt.
Gitweb: http://git.cs.fau.de/?p=katarakt
Homepage: http://git.cs.fau.de/~go18gomu/katarakt/
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