README.SaWMan

SaWMan
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DirectFB proudly presents SaWMan, the Shared application and Window Manager,
as a co-development of Royal Philips and Denis Oliver Kropp.

SaWMan is a new window manager module for use with DirectFB. Its main difference
to the default module is that it allows one process to be an application and window
manager, implementing all kinds of diversity, while SaWMan is only the working horse.

On its own, SaWMan will behave similar to the default window manager, but as soon as
there's an application manager, SaWMan will do synchronous RPCs to that application in
relevant functions of the window manager module. That means it switches to the process
and continues after it has completed the requested call and returned a result. The data
which those calls operate on is already in shared memory, e.g. a window configuration.

The application manager can hook itself into several operations with this, e.g. it can
forbid or modify requested window configurations right before they're actually applied
by SaWMan.

For non-desktop and especially non-pointer environments like TVs, it is important to
provide a simple and convenient layout and focus management. The layout of all windows
can be completely overridden by the application manager, e.g. to implement a screen
tiling mode.

The integration of application management allows easy definition and handling of
application specific constraints. The manager has a list of applications identified
by their name. Launching applications is usually initiated by the application manager
itself, e.g. based on global keys grabbed by an input only window. However, the public
SaWMan interfaces provide a way to send launch/shutdown requests from any application
to the application manager.

While the key grabbing only provides asynchronous notification about keys which are
then handled in the manager's main loop, SaWMan provides a hook to let the manager
basically filter every single input event in a synchronous way, similar to the window
configuration. Critical operations like layout and focus switching are best done in
this callback.

[...]

For more information you can check the more or less documented header files in the
include/ directory, or have a look at 'testman' - a minimal example of a manager
implementation in the samples/ directory. You'll also find a small test program
called 'testrun' which demonstrates launching of applications from another application.


Running testman
----------------

Once you have a session running after setting the option "wm = sawman" you'll notice
that there's nothing new, except the old window manager hacks (builtin keys) are gone.

However, if you start 'testman' from the samples/ directory, you'll see windows being
tiled on the screen, unless these windows have the DWCAPS_NODECORATION flag, e.g. LiTE
and XDirectFB use that.

You can try running "df_andi --dfb:force-windowed" or even simply run df_window.

Hitting F9 cycles the focus through managed windows.
F10 would switch layout modes, but there's only one implemented in the test code.
F11 switches between "smooth software" or "standard (hw/sw)" scaling (for windows only).

The smooth scaling algorithms have also been developed in the scope of this project.


Using testrun
--------------

The command "testrun <name>" will start/stop an application.

Available in the test code are:
	Penguins	df_andi --dfb:mode=640x480,force-windowed
	Windows		df_windows