About

Durden is a free (3-clause BSD) desktop environment for Arcan, thus it requires a working arcan installation, optionally set-up with compatible launch targets etc. See the Arcan repository and wiki for those details.

For a complete list of features and estimated state, see the Features and Status section below.

Authors and Contact

Development is discussed on the IRC channel #arcan on the Freenode network (chat.freenode.org)

2015-2016, Björn Ståhl

Licensing

Durden is Licensed in the 3-clause BSD format that can be found in the licensing file.

The included terminal font, Hack-Bold is (c) Chris Simpkins and licensed under the Apache-2.0 license.

The includede fallback font, Emoji-One is provided free (cc-by 4.0 attribution) by http://emojione.com

Starting / Configuring

Make sure that arcan is built with support for builtin frameservers for terminal, decode, encode, remoting etc. else those features will be missing. Durden probes for available engine features and enables/disables access to these accordingly.

Install by adding or symlinking the durden subdirectory of the git repository to your home appl folder (/home/myuser/.arcan/appl/durden)

Start arcan with the resource path set to whatever directory subtree you want to be able to access for assets when browsing for images, video etc.

e.g. arcan -p /home/myuser/stuff durden

There are numerous other ways for setting this up, see the Arcan wiki and manpages for other namespacing and configuration options.

Default meta keys are META1: MENU and META2:RSHIFT, look into keybindings.lua for the currently mapped defaults. If you don't press any of the META keys during the first n (20 or so) keypresses, it is assumed that your meta bindings are broken and you will be queried for new ones.

Quick! meta1+enter - now you should get a terminal window.

A big point with durden as a desktop environment is to make minimal distinction between static configuration and UI directed reconfiguration. The means for changing settings should look and feel 'the same' no matter if it means exposing configuration changes to external programs using a pipe- command channel, mapping it to an input device, UI element like a button or even a timer.

UI directed configuration is made through global and target menus, accessible using meta1+g for global and meta1+t for target (if a window is selected).

The menus are navigated by default using the arrow keys and enter to select and you can filter the list of shown items by typing. meta1+escape to go back one level, meta1+select to activate but remain in menu, escape to close down.

Any path or menu item in the global or target menu can be bound to a keycombination, and this is done by going to global/input/bind custom. You will be prompted to press the binding you like and then navigate to the menu item you want to bind it to. To bind a sub-menu, hold meta1 while selecting.

It is however also possible to tweak/modify the startup defaults (see autorun.lua, keybindings.lua and gconf.lua).

Timers

Durden does not have explicit settings for suspend/resume, shutdown, lockscreen or similar features. Instead, most commands can be bound to a timer, of which there are three types:

Fire Once(a): about (n) seconds from now, run command (a)
Fire Periodically(a): every (n) seconds from now, run command (a)
Fire Idle(a,b): after (n) seconds of idle (no input activity and active space is not in fullscreen state), run command (a) going into idle, (b) going out.

3 is of particular interest as you can set multiple idle timers. For example> After (30 seconds, run lockscreen with key '1password1'). Then after (60 seconds , disable/enable displays) and finally after 120 seconds, suspend.

The file autorun.lua can also be used to add timers that are set when launched, Make sure the syntax is correct because the entire file will be ignored in the event of parser errors.

Lockscreen

A lockscreen can be setup temporarily by accessing system/lock and enter a one- use password, or as mentioned in the timers section, be bound to an idle timer or similar mechanism.

In addition, it is possible to bind a path to lockscreen success or fail_n_times by modifying gconf.lua, look for lock_ok and lock_fail_ entries. This can be used for strong effects like starting webcam streaming, running external commands or shutting down.

Database Configuration

The launch bar (default meta1+d) uses preconfigured execution profiles that are managed with a separate external tool as part of Arcan, called arcan_db, check the Arcan Wiki for more information.

Recall that for now, we don't implement display server protocols like X11, Wayland or MIR so the set of programs that can be launched and expected to run are fairly limited. See the development progress and timeline for Arcan itself for an idea as to when that will be possible.

There is support for running libretro 'cores' (dynamically linked libraries that wrap input/output/state management for common games and emulators) however.

The specifics for downloading/compiling cores and other data that might be needed is outside the scope here, but an example on how to add a target:

arcan_db add_target mycore RETRO [ARCAN_RESOURCEPATH]/.cores/core.so

will add a target with the name 'mycore' to the default database (homedir/.arcan/arcan.sqlite), using the libretro- binary 'format' and the actual file located relative to the current set resourcepath /.cores/core.so

Then we need a launch configuration, one with empty arguments are usually created with the name 'default' (when launching a target that has only one configuration, you won't be queried about what configuration that will be used).

arcan_db add_config mycore myconfig [ARCAN_RESOURCEPATH]/.assets/somefile

will add a config 'myconfig' to 'mycore' with somefile as first argument.

Most settings are stored in the database, and can either be manually. In the event of a broken configuration (where it is not possible to see or otherwise access relevant menus), it is possible to reset to a default state by calling

arcan_db drop_appl durden

Menu Widgets

in the widget folder, there are a few short example scripts on hooks that are enabled when menu navigation reaches a certain state or the lbar/bbar are used for some things. This feature is intended to help developing quick features like notes and a calculator, but also when using features that becomes easier with 'cheat sheets' like an ASCII table.

Status / Command / Output channels

By default, durden creates three named pipes (FIFO) in the ipc subdirectory of the APPLTEMP namespace (default, same as the durden path you run, but can be changed with the ARCAN_APPLTEMPPATH environment variable).

The respective fifos are called (write-only: status, command) and (read-only: output). Status can be used for providing external information, e.g. open files, available memory, network status and have it mapped on UI components like the status bar. The command protocol is similar to 'lemonbar' (so i3status with output format set to lemonbar can be used) with some additions.

| is used as group separator
%% escapes %
%{fmtcmd} changes format (stateful)

where possible fmtcmd values are:
 F#rrggbb set text color
 B#rrggbb set group background
 F- reset to default text color
 S+ switch to next screen
 S- switch to previous screen
 Sf switch to first (primary) screen
 Sl switch to last screen
 Snum switch to screen index 'num'
 Aidentifier set group "on click" action. This can only be set once for
 each group. If identifier is a valid path (#path/to/cmd or !path/to/cmd)
 on-click will run that path. Otherwise, identifier value will be written
 to output channel on click.

The command channel uses the same format as normal binds, meaning that there is a 'hidden' group of functions and the normal groups that prefix with !path/to/action or !path/to/value=somenum for global actions and #path/to/action for target actions.

of (command, global, target). In addition, the command name or path must be enabled in the built-in table in gconf.lua or manually added through the global/config/command_channel path. The feature works much like normal custom target or global bindings, but with some additional (gfunc.lua) functions available to be exposed.

There are few good mechanisms for probing the available command paths other than reading through the source code in menus, but running arcan durden dump_menus will give a decent aproximation, but some paths are only visible / available when certain preconditions have been fulfilled.

The output ipc channel acts as response for writes to both status and command channels.

Performance

For lower power devices where multi-screen setups isn't needed, simple display mode might be needed. This can be accessed by modifying gconf.lua or while running through Config/System/Display Mode (requires a Reset to activate).

Simple display mode disables some other features as well, e.g. orientation swap, some forms of recording / sharing and others that build on the main surface being rendered to an off-screen buffer.

While somewhat buggy, one might also want to try out mouse_mode = "native" where cursor drawing is treated outside the normal rendering pipeline. This may make the cursor feel more 'smooth' (but at the same time can't be used as an indicator for slowdowns in the rendering pipeline that might be relevant to investigate)

Browser

The built-in browser is currently limited in a number of ways due to arcan engine restrictions. The primary purpose is media selection (for sharing, playlists, navigation) and therefore only shows extensions that have a chance of being 'useful' (while also part of the shared resource- namespace) and does not have the ability to directly alter this space (deletion, moving, renaming) though it is likely that this functionality will be added as a system_load style .so/dll/dylib in the future.

Due to limitations in how arcan glob_resource currently works, it is blocking (nothing else happens until the operation finishes) and unbounded (you get all or nothing, not a cutoff after a certain number of items or time) which means that networked mappings and huge folders can introduce notable stalls, which is of course not acceptible.

Features and Status

To get an overview of the features that have been implemented and features that are being implemented, we have the following list:

Keep in mind that a lot of these features are primarily mapping to what arcan already supports and the remaining job is the user interface mapping rather than time-consuming hardcore development.

Extensions

The above featureset mostly covers what would be useful from a tiling DE perspective, but given the relative minimal effort in adding features that would allow mimicking other DEs ('start' button, dock, control panel, ..) -- some extension scripts and support is planned but not currently implemented (likely to be drop:able into a plugins folder that globbed / scanned on load With some minimal hook api).

start button, popup, control panel

While the status/etc. bar code should probably be replaced with a more flexible system for adding dynamic bars and attachment points, adding a clickable button to work like the normal windows-style start menu should be an easy thing.

The menu-code that uses the lbar currently could trivially be switched over to use such popup-menu style navigation, though some icon field may need to be added.

external widgets

Sweep the database at launch for a specific tag and launch them all at startup, attaching to a fixed size docklet "WindowMaker/NeXTStep style" or as part of the global/target menu screen.

desktop icons / shortcuts

For float layouts, allow local icons and shortcuts to be added for launching, but also for 'minimizing selected window' to desktop icon and some operation to hide/reveal active windows.

advanced keyboard - mouse navigation

Offscreen, run edge detection/amplification, downscale and readback to get a 'navigation map' of continous regions that the mouse cursor can be centered to, allowing much faster cursor positioning with keyboard and "sticky" regions with mouse navigation.

Repository

files that might be of interest)

durden/
    gconf.lua        - configuration management (default visuals and sizes)
    clipboard.lua    - clipboard management
			keybindings.lua  - active keybindings
    fglobal.lua      - global WM functions
			mouse.lua        - mouse gesture support
			shdrmgmt.lua     - shader loading and setup
			symtable.lua     - keyboard layout and input translation
    iostatem.lua     - per window input state machine tracking
			extevh.lua       - default frameserver event handlers
    durden.lua       - main script, input routing and process management
    display.lua      - display and multiple-workspace manager
    tiler.lua        - main tiling layout, workspace management etc.
    wnd_settings.lua - window serialization and restore
    lbar.lua         - support script for textedit control
    uiprim.lua       - UI primitives, buttons etc.
    bbar.lua         - binding bar, used for querying keybindings
    browser.lua      - lbar based resource browser
    suppl.lua        - text and menu convinience functions
    timer.lua        - one-off or recurrent timer events

durden/atypes/* - menus and settings for specific client subtypes
durden/menus/ - global menus and settings, target base menus and settings
	durden/widgets/ - customized menu path- helpers
	durden/shaders/ui/ - code for customizing decorations etc.
	durden/recordings - video recording output stored here
	durden/ipc/ - iopipes will be created here

We don't keep any necessary assets in the resource path as that should be accessible to the browser (one could essentially set it to / or whatever filesystem mount-point one wants).

happy-ferret / durden Goto Github PK

durden's Introduction