feat(rumble): host-authoritative self-terminating envelopes (0xCA v2)

Rumble was level-triggered, unbounded state on a lossy channel: a non-zero
level meant "buzz until further notice", healed only by the host re-sending
state every 500 ms, and every client guessed when the host had died with its own
magic timeout (SDL 1.5 s, Apple 1.6 s, Android up to 60 s). A lost stop, a
reordered start, or a dead host could drone the motor for seconds.

Make "stuck rumble" inexpressible on the wire. The 0xCA datagram grows a
length-tolerant tail — [u8 seq][u16 ttl_ms] — so it self-terminates: the host
authorizes a level for at most ttl_ms and renews it (~120 ms) while it holds,
letting an abandoned one lapse client-side. seq is a per-pad wrapping reorder
gate (reusing GamepadSnapshot::seq_newer) so a reordered stale start can't
re-light a stopped motor. Decoders read the first 7 bytes as a plain level and
ignore the tail, so no wire-version bump: an old client renders a new host's
levels, and a new client falls back to its prior staleness heuristic against an
old host (ttl = None). All four generation pairings render correctly.

- core: encode_rumble_datagram_v2 / decode_rumble_envelope (datagram.rs); the
  client demux applies the seq gate then forwards (pad, low, high, Option<ttl>);
  next_rumble is unchanged (drops ttl), next_rumble_ttl keeps it; ABI adds
  punktfunk_connection_next_rumble2 + PUNKTFUNK_RUMBLE_NO_TTL, ABI_VERSION 4->5
  (WIRE_VERSION unchanged — the tail is backward-compatible).
- host (punktfunk1.rs): the flat 500 ms refresh becomes a renewal loop that bumps
  seq + stamps a fresh TTL on active pads and drains a short post-stop zero burst,
  then goes quiet. Hatches: PUNKTFUNK_RUMBLE_ENVELOPE=0 (legacy v1 + flat refresh,
  a bisect switch), PUNKTFUNK_RUMBLE_TTL_MS (clamped [150, 5000]).
- renderers honor the TTL as their playback duration/deadline and keep their old
  heuristic only for a legacy (ttl=None) update: pf-client-core (the Deck haptic
  keep-alive is now deadline-bounded so it can't sustain a host-stopped rumble),
  clients/windows (SDL duration), android (JNI packs the lease out-of-band in bit
  48 so any u16 ttl is unambiguous; Kotlin createOneShot(ttl)), apple
  (RumbleRenderer.envelopeDeadline + nextRumble2; sessionStaleSeconds demoted to
  the legacy fallback).
- tests: codec round-trip + tail tolerance + seq-gate reorder (Rust); the probe
  asserts the v2 tail arrived under PUNKTFUNK_TEST_FEEDBACK; the Apple loopback
  asserts ttlMs round-trips end to end; RumbleTuning lease-decision cases.

The host-side idle-timeout from the previous commit is defense in depth on the
game side; this is the guarantee on the client side. Design:
punktfunk-planning/design/rumble-envelope-plan.md.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
This commit is contained in:
2026-07-11 03:08:27 +02:00
parent 19e9828e8d
commit 73c911cae4
17 changed files with 734 additions and 91 deletions
@@ -35,6 +35,9 @@ class GamepadFeedback(private val handle: Long) {
const val TAG_LED: Byte = 0x01
const val TAG_PLAYER_LEDS: Byte = 0x02
const val TAG_TRIGGER: Byte = 0x03
// Fallback one-shot duration against a legacy host (no v2 TTL lease): the prior fixed value.
// A new host renews far below this, so it never actually holds this long there.
const val LEGACY_RUMBLE_MS = 60_000L
}
@Volatile private var running = false
@@ -66,7 +69,17 @@ class GamepadFeedback(private val handle: Long) {
while (running) {
val ev = NativeBridge.nativeNextRumble(handle)
if (ev < 0L) continue // timeout / closed
renderRumble(((ev ushr 16) and 0xFFFF).toInt(), (ev and 0xFFFF).toInt())
// ev bit 48 = has a v2 lease; bits 32..47 = ttl_ms; 16..31 = low; 0..15 = high. The
// lease flag is out-of-band, so any ttl_ms (incl. 0xFFFF) is a real lease — no
// in-band sentinel. No lease (legacy host) → the prior long one-shot.
val hasLease = ((ev ushr 48) and 0x1L) == 0x1L
val ttl = ((ev ushr 32) and 0xFFFF).toInt()
val durationMs = if (hasLease) ttl.toLong() else LEGACY_RUMBLE_MS
renderRumble(
((ev ushr 16) and 0xFFFF).toInt(),
(ev and 0xFFFF).toInt(),
durationMs,
)
}
}, "pf-rumble").apply { isDaemon = true; start() }
@@ -143,9 +156,14 @@ class GamepadFeedback(private val handle: Long) {
}
}
/** low = heavy/left motor, high = light/right motor; both 0..0xFFFF (the host's u16 amplitudes). */
private fun renderRumble(low: Int, high: Int) {
Log.i(TAG, "rumble low=$low high=$high") // verification line — BEFORE any no-op return
/**
* low = heavy/left motor, high = light/right motor; both 0..0xFFFF (the host's u16 amplitudes).
* `durationMs` is the host's v2 envelope TTL — the one-shot self-terminates after it unless the
* host renews, so a lost stop (or a dead host) silences at the lease instead of the old fixed
* 60 s. Against a legacy host it is [LEGACY_RUMBLE_MS] (the prior fixed duration).
*/
private fun renderRumble(low: Int, high: Int, durationMs: Long) {
Log.i(TAG, "rumble low=$low high=$high ttlMs=$durationMs") // verification line — BEFORE any no-op return
val lo = toAmplitude(low)
val hi = toAmplitude(high)
val m = vm
@@ -157,12 +175,12 @@ class GamepadFeedback(private val handle: Long) {
val combo = CombinedVibration.startParallel()
if (amplitudeControlled && vibratorIds.size >= 2) {
// ids[0] = light/right, ids[1] = heavy/left (XInput/Moonlight convention).
if (hi != 0) combo.addVibrator(vibratorIds[0], oneShot(hi))
if (lo != 0) combo.addVibrator(vibratorIds[1], oneShot(lo))
if (hi != 0) combo.addVibrator(vibratorIds[0], oneShot(hi, durationMs))
if (lo != 0) combo.addVibrator(vibratorIds[1], oneShot(lo, durationMs))
} else {
// Single motor or no amplitude control: blend both into one effect.
val a = (lo * 0.8 + hi * 0.33).toInt().coerceIn(1, 255)
for (id in vibratorIds) combo.addVibrator(id, oneShot(a))
for (id in vibratorIds) combo.addVibrator(id, oneShot(a, durationMs))
}
runCatching { m.vibrate(combo.combine()) }
return
@@ -175,7 +193,10 @@ class GamepadFeedback(private val handle: Long) {
}
val a = (lo * 0.8 + hi * 0.33).toInt().coerceIn(1, 255)
runCatching {
lv.vibrate(if (amplitudeControlled) oneShot(a) else oneShot(VibrationEffect.DEFAULT_AMPLITUDE))
lv.vibrate(
if (amplitudeControlled) oneShot(a, durationMs)
else oneShot(VibrationEffect.DEFAULT_AMPLITUDE, durationMs)
)
}
}
@@ -185,8 +206,10 @@ class GamepadFeedback(private val handle: Long) {
return if (v16 != 0 && a == 0) 1 else a
}
// Long one-shot held until the next packet (the host re-sends ~periodically); cancel on zero.
private fun oneShot(amp: Int): VibrationEffect = VibrationEffect.createOneShot(60_000L, amp)
// One-shot held for `durationMs` — the host's v2 TTL (renewed while the level holds), so it
// self-terminates on a lost stop; cancel on zero.
private fun oneShot(amp: Int, durationMs: Long): VibrationEffect =
VibrationEffect.createOneShot(durationMs, amp)
// ---- HID output ----
+18 -6
View File
@@ -24,8 +24,12 @@ const TAG_PLAYER_LEDS: u8 = 0x02;
const TAG_TRIGGER: u8 = 0x03;
/// `NativeBridge.nativeNextRumble(handle): Long` — block up to ~100 ms for the next rumble update.
/// Returns `(low << 16) | high` (each 0..=0xFFFF; `0` = stop), or `-1` on timeout / session closed.
/// Pad index is dropped (single-pad model). Run from a dedicated Kotlin poll thread.
/// Returns a packed positive long: bit 48 = "has a v2 lease", bits 32..47 = `ttl_ms`, bits 16..31 =
/// `low`, bits 0..15 = `high` (`low`/`high` 0..=0xFFFF, `0/0` = stop). The lease flag is
/// out-of-band so ANY 16-bit `ttl_ms` — including 0xFFFF — is unambiguous (no in-band sentinel to
/// collide with a real 65535 ms lease). No lease (legacy host) → bit 48 clear, and Kotlin falls
/// back to its long one-shot. `-1` on timeout / session closed (all packed values are positive, so
/// `-1` stays unambiguous). Pad index is dropped (single-pad model). Run from a Kotlin poll thread.
#[no_mangle]
pub extern "system" fn Java_io_unom_punktfunk_kit_NativeBridge_nativeNextRumble(
_env: JNIEnv,
@@ -37,12 +41,20 @@ pub extern "system" fn Java_io_unom_punktfunk_kit_NativeBridge_nativeNextRumble(
if handle == 0 {
return -1;
}
// SAFETY: live handle per the nativeConnect/nativeClose contract; next_rumble is &self on the
// Sync connector — safe alongside the decode/audio/input threads. Kotlin stops these poll
// SAFETY: live handle per the nativeConnect/nativeClose contract; next_rumble_ttl is &self on
// the Sync connector — safe alongside the decode/audio/input threads. Kotlin stops these poll
// threads (and joins them — unbounded) before nativeClose frees the handle.
let h = unsafe { &*(handle as *const SessionHandle) };
match h.client.next_rumble(PULL_TIMEOUT) {
Ok((_pad, low, high)) => (jlong::from(low) << 16) | jlong::from(high),
match h.client.next_rumble_ttl(PULL_TIMEOUT) {
Ok((_pad, low, high, ttl)) => {
// The reorder gate already ran in the core, so this update is fresh. Encode the
// Option out-of-band: a real lease sets bit 48 and carries ttl_ms verbatim.
let (lease_flag, ttl_bits) = match ttl {
Some(ms) => (1i64 << 48, jlong::from(ms) << 32),
None => (0, 0),
};
lease_flag | ttl_bits | (jlong::from(low) << 16) | jlong::from(high)
}
Err(_) => -1, // NoFrame (timeout) or Closed — Kotlin loops on its running flag
}
})