iris: a phone-shaped desktop window, driven by the same touch recordings

Layer 2 of docs/RUST.md's "Three test layers":

    ./run-headless.sh phone --phone --shot /tmp/p.png -- -p transcript-fixture

opens `transcript-fixture`'s screen -- the same fixture and the same
fold the headless tests and the Android bench use -- in a window at the
phone's own 1080x2424 and `content_scale` 2.55, and screenshots it. 15
seconds, warm. `--replay FILE` drives one of the `.touch` recordings
into it and writes `<shot>-before.png` too, so "the list moved" is two
pictures: the flick carries it back about seven turns of the fixture.

Two things this needed.

**The desktop backend now lays out in physical pixels with a density,
exactly as Android does** (`default::content_scale`, overridable with
`IRIS_SCALE`, which is how `--phone` hands it the phone's). It used to
divide winit's coordinates into a separate "logical" space, which left
`UiRenderState::resize` (physical, from `WindowEvent::Resized`) and the
window uniform (logical) disagreeing on any display whose scale factor
is not 1.0, and rasterised glyphs at one resolution to show them at
another. At 1.0 -- every display here -- the numbers are unchanged, and
the `tabs` screenshot is identical.

**`rig-input`'s `replay-touch`** puts a gesture on screen. This
machine's compositor has no pointer to move: sway runs on the headless
backend with no input devices, so `swaymsg seat - cursor press` reports
success and `swaymsg -t get_seats` shows `capabilities: 0`. wlroots 0.19
dropped `WLR_HEADLESS_INPUTS` and ydotool's uinput device would be
ignored by a compositor not reading libinput, so the virtual-pointer
protocol is what is left. It parses the *same* `TouchScript` the
harness does, so one recording drives both layers.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

iris/run-headless.sh

@@ -3,6 +3,25 @@
 #
 #   ./run-headless.sh tabs [-- cargo args]
 #   ./run-headless.sh tabs --shot /tmp/tabs.png --seconds 4
+#   ./run-headless.sh phone --phone --shot /tmp/p.png -- -p transcript-fixture
+#   ./run-headless.sh phone --phone --replay transcript-fixture/touch/flick-120hz.touch \
+#       --shot /tmp/p.png -- -p transcript-fixture
+#
+# `--phone` is layer 2 of docs/RUST.md's "Three test layers": the output
+# and the window take Iris's phone's own size and density (1080x2424 at
+# `content_scale` 2.55, from docs/bench/iris-phone-v2-2026-09-06.md,
+# carried in `transcript_fixture::PHONE_*`), and `IRIS_SCALE` hands that
+# density to iris the way `DisplayMetrics.density` does on Android
+# (`iris::default::content_scale`). So a screenshot from here and one
+# from the phone are the same layout at the same density, and what
+# differs is only the renderer. Without it the output stays desktop-
+# shaped, which is what every other example wants.
+#
+# `--replay FILE` drives one of the `.touch` recordings the headless
+# tests use (`iris/transcript-fixture/touch/`) into the window through
+# `rig-input`'s `replay-touch` -- one recording, both layers. With
+# `--shot` it also writes `<shot>-before.png` from just before the
+# gesture, since "the list moved" is a claim about two pictures.
 #
 # `--bin` runs a real crate binary instead of an example (E4's
 # `desktop-app`, which is a window a person runs, not a demo) --
@@ -29,19 +48,31 @@ here=$(cd "$(dirname "$0")" && pwd)
 run="${XDG_RUNTIME_DIR:-/tmp}/iris-headless"
 seconds=3
 shot=""
+replay=""
 example=""
 kind=example
+phone=no
+
+# The phone Iris runs the bench on. Not typed from memory: these are
+# `transcript_fixture::PHONE_WIDTH`/`PHONE_HEIGHT`/`PHONE_SCALE`, which
+# in turn come from her own reports -- keep the three in step.
+PHONE_MODE=1080x2424@120Hz
+PHONE_SCALE=2.55
+DESKTOP_MODE=1920x1200@60Hz
 
 while [ $# -gt 0 ]; do
     case "$1" in
         --shot) shot=$2; shift 2 ;;
         --seconds) seconds=$2; shift 2 ;;
         --bin) kind=bin; shift ;;
+        --phone) phone=yes; shift ;;
+        --replay) replay=$2; shift 2 ;;
         --) shift; break ;;
         *) example=$1; shift ;;
     esac
 done
-[ -n "$example" ] || { echo "usage: $0 NAME [--bin] [--shot PNG] [--seconds N] [-- cargo args]" >&2; exit 2; }
+[ -n "$example" ] || { echo "usage: $0 NAME [--bin] [--phone] [--replay TOUCH] [--shot PNG] [--seconds N] [-- cargo args]" >&2; exit 2; }
+[ -z "$replay" ] || [ -f "$replay" ] || { echo "run-headless: no touch script at $replay" >&2; exit 2; }
 
 mkdir -p "$run"
 export SWAYSOCK="$run/sway.sock"
@@ -78,6 +109,27 @@ export WAYLAND_DISPLAY
 
 echo "run-headless: $WAYLAND_DISPLAY (sway $(swaymsg -t get_version --raw | sed -n 's/.*"human_readable":"\([^"]*\)".*/\1/p'))" >&2
 
+# Set every run rather than only when it changes: this compositor is
+# reused across runs (see the socket comment above), so a desktop-shaped
+# run after a phone-shaped one would otherwise inherit the phone's output
+# and silently screenshot the wrong size.
+if [ "$phone" = yes ]; then
+    mode=$PHONE_MODE
+    export IRIS_SCALE="$PHONE_SCALE"
+    echo "run-headless: phone-shaped output $PHONE_MODE at IRIS_SCALE=$PHONE_SCALE" >&2
+else
+    mode=$DESKTOP_MODE
+fi
+swaymsg output HEADLESS-1 mode "$mode" >/dev/null
+# The extent `replay-touch` positions against, so a script's coordinates
+# are the output's own pixels.
+out_w=${mode%x*}
+out_h=${mode#*x}; out_h=${out_h%@*}
+
+# Built before the app starts, so a compile error is not reported as a
+# window that failed to move.
+[ -z "$replay" ] || cargo build --bin replay-touch -p rig-input >&2
+
 cd "$here"
 if [ "$kind" = bin ]; then
     cargo build --bin "$example" "$@" >&2
@@ -111,6 +163,18 @@ while [ $i -lt "$((seconds * 2))" ]; do
     i=$((i + 1)); sleep 0.5
 done
 
+if [ -n "$replay" ] && kill -0 "$pid" 2>/dev/null; then
+    if [ -n "$shot" ]; then
+        grim "${shot%.png}-before.png"
+        echo "run-headless: wrote ${shot%.png}-before.png (before the gesture)" >&2
+    fi
+    "$here/target/debug/replay-touch" "$out_w" "$out_h" "$replay"
+    # A fling outlives the finger: the gesture's own last sample is not
+    # when the list stops. Long enough for Android's spline to settle
+    # (`FlingCalculator::duration` tops out around a second and a half).
+    sleep 2
+fi
+
 if kill -0 "$pid" 2>/dev/null; then
     [ -n "$shot" ] && grim "$shot" && echo "run-headless: wrote $shot" >&2
     kill "$pid" 2>/dev/null || true