The cursor channel excluded the host pointer from the video for the whole session, but the client only draws it under the DESKTOP mouse model — flipping ⌃⌥⇧M to capture mid-stream left the session pointer-blind (user-found). The fix makes render ownership LIVE state: - wire: CursorRenderMode 0x51 (client→host, control stream) — client_draws: true = desktop model (host excludes + forwards), false = capture model / released (host composites, full fidelity — DWM on Windows incl. real XOR inversion, encoder blend on Linux). Sessions start client_draws=true (the pre-message behavior). - host: control task stores the flag; the encode loop edge-detects it — forwarding + frame.cursor strip while the client draws, quiet forwarder + overlay-into-blend while composited. SessionPlan now grants blend CAPABILITY wherever the capture has a pointer (dropping the !cursor_forward gate) so the composite side needs no encoder rebuild; per-tick frame.cursor decides what is drawn. - Windows: Capturer::set_cursor_forward → retained IOCTL_SET_CURSOR_FORWARD sender (proto v6) → driver (un)declares the IddCx hardware cursor on the LIVE monitor. Un-declare re-issues the setup with EMPTY caps (candidate mechanism — the DDI has no documented un-setup); resetup-on-commit is skipped while off, so a mode commit's software-cursor default is the fallback path. Failure against a pre-v6 driver logs and keeps declared-at-ADD behavior. - SDL client: one edge-detected reconciler at the cursor pump site — desktop-active = client draws; capture model or released = host composites. Covers the chord, the M3 auto-flip, and engage/release. - C ABI v12: punktfunk_connection_set_cursor_render (additive; wire version unchanged — pre-§8 hosts ignore the unknown message type). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
pf-driver-proto
The shared host ↔ driver binary contract for punktfunk's Windows pf-vdisplay virtual display — the control IOCTLs and the IDD-push frame transport, defined exactly once.
It's a path dependency of both the host workspace (crates/punktfunk-host)
and the out-of-workspace driver workspace (packaging/windows/drivers/),
so it must resolve identically from either build graph. That's why it's deliberately self-contained:
no_std (+ alloc), platform-neutral (GUID/LUID are plain integers each side converts to its own OS
type), and free of *.workspace = true inheritance.
Defining every wire struct here — with const size/offset asserts and bytemuck round-trips — turns
host↔driver ABI drift into a compile error instead of a silent frame or IOCTL corruption.
See the crate root (src/) for the wire types; the Windows virtual-display design is in
the internal planning repo (punktfunk-planning: windows-virtual-display-rust-port.md).