Until the tracking is good enough for a hand-shaped hole, each hand cuts a
disk facing the eye, wide enough for the whole hand plus the margin, drawn
as the stadium around the ellipse each eye sees on the screen with a soft
edge. mesh and capsules stay selectable (HANDS_MATTE, cutouts matte).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- handcut: reads fh_hands version 2 (the skeleton's joints, radii, elbow, pinch point; version 1
still works) and the gestures file; the matte is hand-shaped: a tapered capsule per finger
bone, the palm and the thumb's web as convex slabs, the forearm toward the elbow, drawn with
a soft-edged convex polygon shader; its margin is an angle from the eyes plus motion
(HANDS_MATTE_MARGIN, _MOTION, _MOTION_MAX), the capsules stay selectable (HANDS_MATTE), and a
per-distance correction hook is off by default (HANDS_MATTE_SHIFT). The CPU part is in
handcut.cpp (no GPU or SteamVR calls), the renderer in handrender.cpp.
- handinput: the near claim, poke to click (index straight and nearest, two frames at the
surface, an approach speed or 1 cm deep, release 1.5 cm out or 1 cm back, the click held
still until a 1.5 cm slide, re-press guard, through-the-panel release), pokes on the curve,
reset, dock and close buttons, pinch on the bar, edges, corners, tab or title bar to move
(facing the head) or resize, two hands to stretch and turn, two hands to one, lost hands.
- vr.cpp: hands read once per tick, "hands <L> <R> <allowed>" from the pointer helper, "near
<capture_ns> <L> <R>" to it per hands frame, want-hz while near, glows on the cutout buffer,
hand holders for KWin's button and carried panels, the handinput and cutouts commands.
- tests/handinput_test.cpp: unit tests, and replays of ft-handreplay --publish-dump
(scripts/test-handinput.sh, justfile test-c).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A see-through test panel with dots on the wrist, middle knuckle and fingertips of each
tracked hand, one colour per timing: where the cameras saw the hand, moved ahead to now,
and moved ahead to now + the cutouts' lead. Recorded together with the headset view, they
show how far the cutouts land from the hand Room View shows, still and moving, and which
lead fits. Each tick goes to a JSON-lines log. Renderer::Marks draws the dots; Hands::Points
gives the landmarks. ft-screens' cutouts are unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The cutout composite drew each screen's whole client buffer into a side-by-side buffer on
every tick a hand was in front of it, then waited for the GPU with glFinish (1-6 ms, the
likely cause of the VR frame drops on 2026-10-01). Now:
- A drawn buffer gets a fence and is shown from a later tick once the fence has passed, so
ft-screens never waits for the GPU (except for a panel's first buffer after a pause, so a
stale one never shows). The prediction lead goes from 25 to 36 ms for that tick.
- Nothing is drawn when the client frame and the cutouts haven't changed, and SteamVR
isn't handed the same buffer again.
- When only the cutouts moved, a buffer that holds the same client frame is drawn again
only around the old and new cutouts (scissored).
- "cutouts state" reports draws, partial draws, unchanged ticks, busy ticks, waits and CPU
time per second since the last state; ft-handtest prints the same counts.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- The runtime files move to /run/user/UID/frametop-hands/: the desktop
session deletes /run/user/UID/frametop at every start.
- The cutout copy shader runs at highp: mediump (16-bit on Adreno)
stepped 1.7 texels across a 3440-pixel screen.
- One hand no longer pinches both sides after its left/right call flips
mid-pinch, and --pinch-palm-down (0.6) holds back pinches with the palm
facing down (typing on a lap keyboard).
- ft-camd judges a colour frame fresh by its luma rows only, and logs
per-buffer changes at stale colour frames with FT_CAMD_DEBUG=1.
- hands/run.sh caps skips the setcap when ft-camd already has them.
- The replay tool dumps poses (--poses), and its pinch events carry the
hand id.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ft-screens' hand cutouts read /run/user/UID/frametop/hands through
hands/include/fh_hands.h instead of their own copy of its offsets.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Where frame-hands tracks a hand between an eye and a screen, that eye sees the
room through the screen. handcut.cpp draws the screen's buffer side by side
(one half per eye) with the hands cut out, only while a hand is in front of it.
The cutouts command turns it on or off. ft-handtest tries it on a test panel.
Not yet tested in the headset.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
