.TH 12to11
.SH NAME
12to11 - Wayland to X protocol translator
.SH SYNOPSIS
.B 12to11
[\-\fIclass\fP class] [\-\fIname\fP name]
.SH DESCRIPTION
.I 12to11
starts a Wayland compositor on the next available socket;
Wayland programs will then be displayed through the X server.
.SH OPTIONS
Some X Toolkit library-style command-line arguments are also accepted,
despite the protocol translator being implemented without using a
toolkit.  These options are:
.TP 8
.B \-class \fIclass\fP
This option specifies the resource class under which resources are to
be obtained.  When not set, it defaults to the string ``12to11''.  The
resource class and name used by the protocol translator are \fInot\fP
set as the
.B WM_CLASS
property on windows created by the protocol translator; instead, those
windows get the classes and names assigned to them by their individual
Wayland clients.
.TP 8
.B \-name \fIname\fP
This option specifies the instance name under which resources are to
be obtained.  When not set, it defaults to the executable file name.
.TP 8
.B \-help\fP
This option causes the protocol translator to print a message
describing options it accepts.  The protocol translator will then exit
after printing the message.
.SH RESOURCES
\fI12to11\fP understands some resource names and classes that can be
used to specify various settings that affect its behavior.  Those
resources are listed below:
.TP 8
.B ximFont\fP (class \fBXimFont\fP)
Specifies the font to be used for displaying the preedit or status
areas of an input method.
.IP
In many input methods, the preedit (a.k.a composition or
preconversion) string and/or a status window is displayed on screen
while typing by the input method server.  The client is supposed to
determine the font used by the input method server to display --
however, the Wayland protocol does not allow Wayland clients to
specify that themselves, so the protocol translator has to do that by
itself.
.TP
.B ximStyles\fP (class \fBXimStyles\fP)
Specifies the default input method styles used by the protocol
translator.
.IP
X input methods can support different editing styles, which affect how
preconversion and status text is displayed while typing.  These styles
are named:
.TP
.I overTheSpot
In ``over the spot'', the preedit string is displayed in a window
created by the input method at a location specified by the Wayland
client, typically the text insertion point.
.TP
.I offTheSpot
In ``off the spot'', the preedit string is displayed in a window
created by the input method at some location away from the text
insertion point.  Often, this type of window is placed at the bottom
of the preedit window.
.TP
.I rootWindow
In the ``root window'' editing style, the preedit string is displayed
in a popup window created by the input method.
.TP
.I onTheSpot
In the ``on the spot'' editing style, the preedit string is displayed
inside the text itself by the Wayland client.
.PP
Not all input methods support all editing styles.  In the real world,
most only support one or two of the styles listed above.  The protocol
translator will search for a style supported by the input method when
initializing input method support.  The \fBximStyles\fP resource is
used to control the order in which the protocol translator searches
for input styles, and should be a comma separated list of input names,
which are searched in left-to-right order.  For example,
.PP
.in +4
.EX
\fBoverTheSpot,rootWindow\fP
.EE
.in
.PP
will result in the protocol translator searching for the ``over the
spot'' input style, and if that is not present, the ``root window''
style.  Whitespace must not be present inside the comma-separated
list.  When \fBximStyles\fP is not specified, it defaults to:
.PP
.in +4
.EX
\fBoverTheSpot,offTheSpot,rootWindow,onTheSpot\fP
.EE
.in
.SH ENVIRONMENT
Several environment variables exist that modify the behavior of the
protocol translator in one way or another.  Most of these are used for
debugging, but some may be relevant to users as well.
.PP
The
.B USE_BUILTIN_RESIZE
environment variable, if set, forces the use of the built-in
drag-to-resize support provided by the protocol translator, even if
the X window manager provides its own.
.PP
The
.B DEBUG_REFRESH_PREDICTION
environment variable, if set, forces the frame clock to predict the
presentation deadline of the X compositing manager.  This is used to
debug code that is otherwise not run without subsurfaces being
present.
.PP
The
.B DISABLE_FRAME_SYNCHRONIZATION
environment variable, if set, disables frame synchronization with the
X compositing manager.  Setting this variable is probably not a good
idea.
.PP
The
.B SYNCHRONIZE
environment variable, if set, causes the X library to check for errors
immediately after issuing a request.  The resulting backtraces from
the error handler then reflect the protocol request that actually
caused the error, instead of some unpredictable request in the future.
.PP
The
.B APPLY_STATE_WORKAROUND
environment variable, if set, causes the protocol translator to handle
toplevel window state changes differently.  If Wayland programs do not
make the transition between fullscreen and maximized states correctly,
try setting this variable.
.PP
The
.B GLOBAL_SCALE
environment variable, if set to an integer, overrides the global
program scale factor normally provided by the
.I Gdk/WindowScalingFactor
X setting.
.PP
The
.B OUTPUT_SCALE
environment variable, if set to an integer, overrides the output scale
factor that is otherwise set to the global program scale factor.
Setting this option is only useful to debug Wayland program
downscaling.
.PP
The
.B DIRECT_STATE_CHANGES
variable, if set, forces ConfigureNotify events from the window
manager to be handled directly, without waiting some time for a
corresponding _NET_WM_STATE event to arrive.  This is only
useful for debugging the window resizing logic.
.PP
The
.B RENDERER
variable, if set, controls the rendering backend used by the
protocol translator.  When set to
.I help
it prints a list of available rendering backends instead.
.PP
The
.B RENDER_VISUAL
variable, if set to a number, contains the ID of the visual used
when the EGL rendering backend is in use.
.SH BUGS
There is a hard to catch bug where Wayland programs leaving the
fullscreen or maximized state may abruptly return to their maximized
size.  Setting the
.B APPLY_STATE_WORKAROUND
environment variable may help.
.PP
Mozilla Firefox also does not work correctly.  Resizing the Firefox
window leads to screen tearing, and Firefox often resizes its toplevel
windows outside their normal boundaries, causing invalid screen
contents to be displayed over other applications.
.PP
Using this protocol translator under a window manager that does not at
least support the
.B _NET_WM_SYNC_REQUEST
and
.B _NET_WM_STATE
window manager hints will result in Wayland programs running
incorrectly.
.SH "SEE ALSO"
X(7), Xorg(1)
.SH AUTHOR
Various contributors.