Model playback latency from the device period, arrival jitter, source
packet phase, and resampler delay. Treat audio:latencyOffset as an
explicit addition to this minimum and align the first device pull to
the next packet deadline. This starts playback near its steady-state
target without unnecessary prefill or startup underruns. Use a
512-frame default period as a practical low-latency baseline.
Replace the startup clock hold with a one-sided proportional
acquisition controller, then hand off to source/device rate
feed-forward and a slow phase loop. Calibrate the logical device
timeline at handoff, discard correction that opposes the current
error, and slew-limit rate changes. This prevents startup drain,
integral wind-up, overshoot, and long convergence while preserving
clock-drift compensation.
Allow audio backends to expose a real-time resampler and use
PipeWire's adaptive resampler when version 1.4 or newer supports it.
Retain libsamplerate as the fallback and add audio:resampler to select
the implementation. Wait for PipeWire stream setup to complete and
propagate rate-control failures cleanly.
Track PipeWire input-consumption and output-equivalent clocks
separately. The input clock measures ring latency while the output
clock drives feed-forward using the ratio that governed each request.
This removes delayed self-feedback that made adaptive resampling
oscillate between the correction limits.
Reduce audio:debug output to useful latency, clock, jitter, and xrun
values, and scale the playback graph from the startup estimate. Update
the option names and documentation for the new latency model.
Drive playback timing from audio sample positions instead of packet
arrival cadence. Use SPICE multimedia timestamps to anchor streams,
detect discontinuities, and estimate the long-term source rate. Ignore
their coarse phase corrections when steering the playback buffer.
Measure the device clock independently and wait for it to stabilize
before enabling a bounded, slew-limited phase controller. Align startup
buffering from logical producer and consumer positions so backend
startup reserves do not become persistent latency.
Size the buffer from the backend period, measured delivery jitter, and
resampler delay. Update PipeWire and PulseAudio to report their actual
startup requirements and presentation latency. Default to a 10 ms
device period with 4 ms of additional buffering, and make detailed
synchronization diagnostics opt-in through audio:debug.
This reduces startup and steady-state latency while compensating for
physical and virtual device clock drift without reacting to transport
jitter or SPICE timestamp quantization.
This change alters the small square dot cursor to a more visible 16x16
cursor for X11. A new option `spice:largeDotCursor` can be set to use an
alternative 32x32 cursor for the vision impaired.
This makes it possible to define the escape key by name rather then just
it's integer code, while still allowing fallback to using an integer
value for codes that may not be defined.
Example: `input:escapeKey=KEY_F1`
An invalid string value will also print a list of all valid string
values.
The current minimum target latency is partially based upon the default qemu
behaviour whereby audio packets are delivered in a sawtooth pattern, with
packet timestamps drifting between 5ms above and below the measured clock.
This 5ms error is baked into the minimum target latency to avoid
underrunning.
This sawtooth pattern can be reduced by specifying a lower timer period in
the qemu configuration, so remove it from the hardcoded minimum latency and
add it to the default configurable buffer latency instead. This allows
users that have configured their VM appropriately to reduce the overall
latency.
This adds a new `audio:bufferLatency` option which allows the user to
adjust the amount of buffering LG does over the absolute bare minimum. By
default, this is set large enough to absorb typical timing jitter from
Spice. Users may reduce this if they care more about latency than audio
quality.
This adds a new `audio:periodSize` option which defaults to 2048 frames.
For PipeWire, this controls the `PIPEWIRE_LATENCY` value. For PulseAudio,
the controls the target buffer length (`tlength`) value.
This adds a new `earlyInit` call which allows the overlay to register
options before actually being intialized. Also the keybind handling and
state tracking for each overlay has been moved internal to the overlay
itself.
Without configuring Wayland compositors to send frame callbacks as late as
possible, JIT rendering can increase latency by more than one frame.
For example, by default, sway asks applications to render right after a
vblank, and does its own composition right after a vblank, resulting in
~2 frame's worth of latency. If max_render_time is set on the output,
it composes that many milliseconds before the vblank, losing ~1 frame's
worth of latency. If max_render_time is set on the window also, the frame
callback is sent that many milliseconds before composition, and we achieve
perfectly low latency.
Therefore, out of the box, JIT rendering should not be enabled, as manual
compositor configuration is required for optimal results.
For reference, the following sway settings results in the best latency:
output <insert output name> max_render_time 1
for_window [app_id="looking-glass-client"] max_render_time 1
This reverts commit 3baed05728.
When requested, JIT render mode will be used if the display server supports it.
Otherwise, a warning is generated instead.
This essentially uses the signalNextFrame logic for imgui, but for everything.
We automatically enable this mode when overlay is on.
Currently, this exposes some damage tracking bugs in the EGL renderer.
We look for the client config in $XDG_CONFIG_HOME/looking-glass/client.ini.
This is done because it's more conventional, and also allows us to add
additional configuration files, e.g. for the host.
We fallback to $HOME/.config as is standard, and then as a last resort use
getpwuid(getuid())->pw_dir. This is also recommended by the getpwuid manpage:
> An application that wants to determine its user's home directory should
> inspect the value of HOME (rather than the value getpwuid(getuid())->pw_dir)
> since this allows the user to modify their notion of "the home directory"
> during a login session.
Currently, we load /etc/looking-glass-client.ini and/or
~/.config/looking-glass-client.ini as long as they exist, even if they are
not files. We should only load them if they are files.
The refresh-copyright script now automatically updates the copyright string
embedded in config.c. In order to achieve this, refresh-copyright gained the
ability to reflow text as the situation needs.
