punktfunk/docs/releases/v0.19.0.md

Wire-compatible with 0.18.x — existing pairings and clients keep working. The new stylus plane is capability-negotiated (HOST_CAP_PEN) and rides an additive datagram that older peers never send and never have to parse, so a 0.18 host and a 0.19 client (or the reverse) pair exactly as before and simply fall back to pen-as-touch. WIRE_VERSION stays 2; the embeddable C ABI moves to 13 for one new entry point (punktfunk_connection_send_pen); the Windows display-driver protocol is unchanged at 6 (compat floor 3).

Pen, stylus & tablet — a whole new input plane

Punktfunk streams now carry a first-class, pressure-sensitive stylus, end to end and on every platform. It is its own wire plane — not mouse events in disguise — so pressure, tilt, hover and barrel buttons survive the trip from glass to host.

• The wire (P0). A state-full RICH_PEN datagram carries batches of up to 8 samples — sub-pixel f32 position, u16 pressure, hover distance, tilt + azimuth, an eraser tool, and two barrel buttons — ordered by a wrapping sequence number and dropped whole when stale, so a late batch never rewrites the present. A PenTracker coalesces the stream and HOST_CAP_PEN advertises the plane; toward a host without the bit the client keeps its pen-as-touch fallback.
• Linux host (P1). A per-session uinput virtual graphics tablet injects the full stylus — pressure and tilt included — and tears down with the session. HOST_CAP_PEN goes live wherever uinput is available.
• GameStream / Moonlight (P2). The host ingests Moonlight's SS_PEN/SS_TOUCH pointer packets and advertises the matching featureFlags, so a capable Moonlight client sends real stylus onto the same plane.
• Windows host (P3). PT_PEN + PT_TOUCH synthetic pointer injection drives the Windows pen stack directly — pressure and barrel buttons reach applications as genuine pen input.
• iPad (P4). Apple Pencil (including Pencil Pro) capture maps onto the stylus plane — pressure and tilt from the panel, with the cursor-capability fix so the pencil and the pointer coexist.
• Android (P5). Active-stylus capture (S Pen and friends) forwards onto the pen plane with pressure and tilt.

Touch injection, fixed

• Windows native touch actually injects now. PT_TOUCH pointer ids must be contiguous injector slots, but the host was passing the raw wire touch ids straight through — Windows rejected them silently and Moonlight-native multitouch landed nothing. Wire ids are now compacted into slots, and the first rejection is surfaced with a warning instead of vanishing.
• NaN pressure no longer drops a finger. VoidLink's finger touches arrive with a NaN pressureOrDistance; the GameStream path discarded the whole packet. It now tolerates NaN and injects the touch.

Cursor & pointer polish

• The forwarded cursor is scaled to the video fit on the SDL/Linux and Apple/macOS clients. A high-DPI host pointer was drawn against the client's own backing scale and came out roughly 2× too large; it now renders true-size against the streamed video.

Windows host fixes

• No more 0x57 on display-config isolate. When a supplied CCD path is doomed (a Steam Deck's live-deactivate always is), the isolate escalates to a keep-only supplied config instead of failing the whole apply with 0x57.
• Cursor exclusion is reported adapter-wide. The IddCx declare's cursor exclusion is not a per-target property; the virtual-display driver now reports cursor_excluded across the adapter.
• Secure-desktop cursor stood down. The IddCx hardware cursor is held down while the Windows secure desktop (UAC / Winlogon) is up, ending the duplicated/stuck pointer there.

Gamepad

• A virtual Steam Deck pad no longer degrades to a DualSense because of an unrelated Steam controller. To stop Steam Input from double-driving two identical controllers, the host downgrades a requested virtual Steam pad to a DualSense when a matching physical Valve controller is present — but the gate matched any 28DE (Valve) device. So plugging a physical Steam Controller 2 (28DE:1302) into the host dropped a client's virtual Steam Deck (28DE:1205) to the wrong pad — the passthrough came up as a DualSense. The gate now keys on the exact VID+PID: distinct Steam controllers coexist (Steam Input drives them side by side fine), and only a genuine same-identity duplicate — a physical Deck alongside a virtual Deck — still degrades.

Android input — mouse & keyboard regressions

Two regressions from 0.18.0's mouse-&-keyboard overhaul, felt most on Android TV boxes:

• Mouse back/forward stays in the stream. A mouse's back/forward buttons were synthesized by the reader as SOURCE_MOUSE key events and leaked into Android navigation (yanking you out of the stream on a TV); they're now swallowed while streaming.
• Hardware typing no longer pops the IME. The soft keyboard is gated on imeShown, so typing on a physical keyboard against a text-input host doesn't summon the on-screen IME.

Release & CI

• Release notes now ship with the release. Notes are authored in-repo at docs/releases/vX.Y.Z.md and seeded into the release body at creation, and stable releases announce to the Discord #releases channel. This file is the first of them.
• iOS .ipa attached. The iOS build exports an App Store-signed .ipa to the unified release and to the run artifacts (archival/TestFlight, not a direct sideload).

Versions

WIRE_VERSION 2 (unchanged — 0.18.x hosts and clients interoperate) · C ABI 13 (adds punktfunk_connection_send_pen; embedders recompile) · Windows display driver protocol 6, compat floor 3 (unchanged — pen injects through the Windows pen stack, not the display driver). Windows drivers ship separately, as always.