UI key presses are still handled by regular X events, but in-game
"button" presses arrive via raw keyboard events. This gives transparent
handling of keyboard repeat (UI keys see repeat, game keys do not),
without messing with the server's settings (yay, that was most annoying
when it came to debugging), and the keyboard is never grabbed, so this
is a fairly user-friendly setup.
At first, I wasn't too keen on capturing them from the root window
(thinking about the user's security), but after a lot of investigation,
I found a post by Peter Hutterer
(http://who-t.blogspot.com/2011/09/whats-new-in-xi-21-raw-events.html)
commenting that root window events were added to XInput2 specifically
for games. Since application focus is tracked and unfocused key events
are dropped very early on, there's no way for code further down the
food-chain to know there even was an event, abusing the access would
require modifying the x11 input code, in which case all bets are off
anyway and any attempt at security anywhere in the code will fail,
meaning that nefarious progs code and the like shouldn't be a problem.
After a lot of thought, it really doesn't make sense to have an option
to block mouse input in x11 (not grabbing or similar does make sense, of
course). Not initializing mouse input made perfect sense in DOS and even
console Linux (SVGA) what with the low level access.
It turns out that if the barriers are set on the app window, and the app
grabs the pointer (even passively), barrier events will no longer be
sent to the app. However, creating the barriers on the root window and
the events are selected on the root window, the barrier events are sent
regardless of the grab state.
The kernel knows nothing about X11 application focus, so we need to take
care of it ourselves.
Device add/remove events are unaffected: the are always passed on.
Other subsystems, especially low-level input drivers, need to know when
the app has input focus. eg, as the evdev driver uses the raw stream
from the kernel, which has no idea about X application focus (in fact,
it seems the events are shared across multiple apps without any issue),
the evdev driver sees all the events thus needs to know when to drop
them.
It turns out to be possible to get a barrier event at the same time as a
configure notify event (which rebuilds the barriers), and trying to
release the pointer at such a time results in a bad barrier error and
program crash. Thus check the event barrier against the currently
existing barriers before attempting to release the pointer.
This does mean that a better mechanism for sequencing window
repositioning and barrier creation may be required.
This should be a much friendlier way of "grabbing" input, though I
suspect that using raw keyboard events will result in a keyboard grab,
which is part of the reason for wanting a friendly grab.
There does seem to be a problem with the mouse sneaking out of the
top-right and bottom-left corners. I currently suspect a bug in the X
server, but further investigation is needed.
This is needed for getting window position info into in_x11 without
exposing more globals, and is likely to be useful for other things,
especially as it doubles as a resize event when that's eventually
supported.
This is the first step in the long-sought goal of allowing the window
size to change, but is required for passing on getting window position
and size information (though size is in viddef, it makes sense to pass
both together).
This is necessary in focus-follows-mouse environments (at least for
openbox, but it wouldn't surprise me if most other WMs behave the same
way) because the WMs don't set focus when the pointer is grabbed (which
XInput does before the WM sees the enter event). This is especially
important when the window is fullscreen on a multi-monitor setup as
there is no border to *maybe* catch the mouse before it enters the
window.
Right now, only raw pointer motion and button events are handled, and
the mouse escapes the window, and there are some issues with focus in
focus-follows-mouse environments. However, this should be a much nicer
setup than DGA.
The current limit is still 32. Dealing with it properly will take some
rather advanced messing with XInput, and will be necessary assuming
non-XInput support is continued.
There's now IN_X11_Preinit, IN_X11_Postinit (both for want of better
names), and in_x11_init. The first two are for taking care of
initialization that needs to be done before window creation and between
window creation and mapping (ie, are very specific to X11 stuff) while
in_x11_init takes care of the setup for the input system. This proved
necessary in my XInput experimentation: a passive enter grab takes
effect only when the pointer enters the window, thus setting up the grab
with the pointer already in the window has no effect until the pointer
leaves the window and returns.
This was always a horrible hack just to get the screen centered on the
window back when we were doing fullscreen badly. With my experiments
with XInput, it has proven to be a liability (I'd forgotten it was even
there until it started imposing a 2s delay to QF's startup).
Input driver can now have an optional init_cvars function. This allows
them to create all their cvars before the actual init pass thus avoiding
some initialization order interdependency issues (in this case, fixing a
segfault when starting x11 clients fullscreen due to the in_dga cvar not
existing yet).
Well... it could be done better, but this works for now assuming it's in
/usr/include (and it's correct for mxe builts). Does need proper
autoconfiscation, though.
Seems to work nicely for keyboard (though key bindings are not
cross-platform). Mouse not tested yet, and I expect there are problems
with it for absolute inputs (yay mouse warp :P).
I have no idea why it was necessary, and certainly should not be now as
any such portability issues should be tucked away such that the client
code never sees such.
I didn't notice that uint is defined somewhere on Linux... until I tried
compiling for windows (not defined). Use a define to keep the cast
function naming nice.
Mouse axis and button names are handled internally (and thus
case-insensitive).
Key names are handled by X11. Case-sensitivity is currently determined
by Xlib.
keyhelp provides the input name if it is known, and in_bind tries to use
the provided input name if not a number. Case sensitivity for name
lookups is dependent on the input driver.
Everything is set up so default recipes work as expected (by me) for a
3Dconnexion SpaceNavigator:
translation axes move quakeguy in the direction the puck is moved
tilting the puck forward pitches forward (look down)
tilting the puck to the left rolls to the left
twisting the puck clockwise (looked at from the top) turns quakeguy
to the right.
This does mean that the default pitch motion for a regular mouse is now
push forward to pitch forward (look down) (inverted from before).
Mouse scaling is out (too small), but that's because in_amp etc are
ignored for now (thinking about how to integrate cvars with axis
recipes). Joystick input will be the same.
Reset the blocks completely when loading configs and fix a leftover from
when I thought I'd expose the block numbers to bindings but then changed
my mind to simply track the base binding.
The cooked inputs (ie_key, ie_mouse) are intended for UI interaction, so
generally should have priority over the raw events, which are intended
for game interaction.
There's now an internal event handler for taking care of device addition
and removal, and a public event handler for dealing with device input
events in various contexts In particular, so the clients can check for
the escape key.
Saving is not so important, but for loading, while the input system
doesn't make much use of cvars at this stage, it makes sense for them to
be loaded before the input system configuration is loaded.
While the console command line is quite good for setting everything up,
the devices being bound do need to be present when the commands are
executed (due to needing extra data provided by the devices). Thus
property lists that store the extra data (button and axis counts, device
names/ids, connection names, etc) seems to be the best solution.
Recipes themselves still use float, but using double in the cexpr values
allows bare floating point numbers (which parse as double) to be used,
making the bind command line a little more user-friendly.
Bill Currie