Web app: 3D mouse navigation through the Gamepad API (#1473)

The web app reads a 3D mouse through the Gamepad API and drives the camera through navigation::device, so it follows each page's navigation capabilities (#1336).

Co-authored-by: CamWight <CamWight@users.noreply.github.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

apps/solidcraft-web/src/main.rs

@@ -10,6 +10,8 @@
 mod files;
 #[cfg(target_arch = "wasm32")]
 mod install;
+#[cfg(any(target_arch = "wasm32", test))]
+mod space_mouse;
 
 #[cfg(target_arch = "wasm32")]
 mod web {
@@ -21,6 +23,7 @@ mod web {
     use wasm_bindgen::JsCast as _;
 
     use crate::files::{self, Files, Intent};
+    use crate::space_mouse::SpaceMouse;
 
     const CANVAS_ID: &str = "solidcraft_canvas";
     const LOADING_ID: &str = "solidcraft_loading";
@@ -67,6 +70,7 @@ mod web {
         /// On-demand CJK font: fetched only when a CJK language is selected.
         font: solidcraft_ui_egui::fonts::CjkFontLoader,
         font_result: FontLoadResult,
+        space_mouse: SpaceMouse,
     }
 
     impl Shell {
@@ -382,11 +386,14 @@ mod web {
         fn logic(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
             self.tick_font(ctx);
             self.app.logic(ctx);
+            self.space_mouse.logic(&mut self.app, ctx);
             self.files_tick(ctx);
             UNSAVED.with(|u| u.set(solidcraft_ui_egui::documents::any_dirty(&self.app)));
         }
-        fn raw_input_hook(&mut self, _ctx: &egui::Context, raw: &mut egui::RawInput) {
+        fn raw_input_hook(&mut self, ctx: &egui::Context, raw: &mut egui::RawInput) {
             files::take_drops(&self.files, raw);
+            // Before the app's own hook, which adds the control channel's events.
+            self.space_mouse.raw_input_hook(ctx, self.app.preferences.space_mouse_enabled, raw);
             self.app.raw_input_hook(raw);
         }
         fn ui(&mut self, ui: &mut egui::Ui, _frame: &mut eframe::Frame) {
@@ -516,6 +523,7 @@ mod web {
                             recents_synced: false,
                             font: Default::default(),
                             font_result: Rc::new(std::cell::RefCell::new(None)),
+                            space_mouse: SpaceMouse::default(),
                         }))
                     }),
                 )

apps/solidcraft-web/src/space_mouse.rs

@@ -0,0 +1,351 @@
+//! The 3D mouse in the browser (#1336), through the Gamepad API.
+//!
+//! Chromium browsers list a 3Dconnexion device itself, with its six axes scaled to -1..1 from the
+//! device's ±350. Firefox lists only joysticks and gamepads (a 3D mouse is a HID multi-axis
+//! controller), but 3DxWare's virtual joystick carries the same six axes once 3DxWare's profile
+//! for Firefox sends them there. Both come in the device's own order and signs, so the shared
+//! navigation takes them with 3DxWare's object-mode mapping, as the Linux app does without a
+//! profile.
+
+use solidcraft_ui_egui::space_mouse::{Axes, FULL_SCALE};
+
+/// Seconds after the cap last moved that wheel events are still taken for 3DxWare's: one can be
+/// queued just before the cap stops and only reach the next frame.
+const WHEEL_QUIET_S: f64 = 0.15;
+
+/// Logitech's vendor id, which older 3Dconnexion devices carry, and those devices' product ids
+/// (usb.ids). Logitech's own gamepads and wheels carry the same vendor id.
+const LOGITECH: u16 = 0x046d;
+const LOGITECH_3D_MICE: [u16; 11] = [0xc603, 0xc605, 0xc606, 0xc621, 0xc623, 0xc625, 0xc626, 0xc627, 0xc628, 0xc629, 0xc62b];
+/// 3Dconnexion's own vendor id. The browser lists only its 3D mice as gamepads: its mice, and the
+/// mouse side of its receivers, are not gamepads.
+const THREEDCONNEXION: u16 = 0x256f;
+/// 3DxWare's virtual joystick.
+const VIRTUAL_JOYSTICK: (u16, u16) = (0xbeef, 0x046d);
+
+/// What a gamepad the browser lists is, when it is a 3D mouse. A device is read before the
+/// joystick: in a Chromium browser both are listed, and the joystick stays at rest.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
+pub enum Source {
+    Device,
+    VirtualJoystick,
+}
+
+/// The vendor and product ids in a gamepad's id: `Name (Vendor: 046d Product: c62b)` in Chromium
+/// browsers, `046d-c62b-Name` in Firefox.
+fn vendor_product(id: &str) -> Option<(u16, u16)> {
+    fn hex(digits: &str) -> Option<u16> {
+        if (1..=4).contains(&digits.len()) && digits.bytes().all(|b| b.is_ascii_hexdigit()) { u16::from_str_radix(digits, 16).ok() } else { None }
+    }
+    if let Some((_, ids)) = id.rsplit_once("Vendor: ") {
+        let (vendor, rest) = ids.split_once(" Product: ")?;
+        let product = rest.split(|c: char| !c.is_ascii_hexdigit()).next()?;
+        return Some((hex(vendor)?, hex(product)?));
+    }
+    let mut parts = id.splitn(3, '-');
+    let (vendor, product, _name) = (parts.next()?, parts.next()?, parts.next()?);
+    Some((hex(vendor)?, hex(product)?))
+}
+
+/// Whether a gamepad is a 3D mouse, from the id the browser gives it.
+pub fn source(id: &str) -> Option<Source> {
+    match vendor_product(id)? {
+        VIRTUAL_JOYSTICK => Some(Source::VirtualJoystick),
+        (THREEDCONNEXION, _) => Some(Source::Device),
+        (LOGITECH, product) if LOGITECH_3D_MICE.contains(&product) => Some(Source::Device),
+        _ => None,
+    }
+}
+
+/// The six axes in the device's raw units, from a gamepad's axes (-1..1). Fewer than six: not a
+/// 3D mouse. A value that isn't a number reads as rest.
+pub fn axes(values: &[f64]) -> Option<Axes> {
+    let raw = |i: usize| values.get(i).map(|&v| if v.is_finite() { (v.clamp(-1.0, 1.0) * f64::from(FULL_SCALE)).round() as i16 } else { 0 });
+    Some(Axes { translation: [raw(0)?, raw(1)?, raw(2)?], rotation: [raw(3)?, raw(4)?, raw(5)?] })
+}
+
+/// The 3D mouse to read among the ones listed: the first device, else the first joystick.
+pub fn choose(found: impl IntoIterator<Item = (Source, Axes)>) -> Option<Axes> {
+    found.into_iter().min_by_key(|(source, _)| *source).map(|(_, axes)| axes)
+}
+
+/// 3DxWare turns the cap's motion into mouse-wheel turns in a browser (its zoom emulation). The
+/// app reads the cap itself, so those are dropped: wheel events while the cap is moving and for
+/// [`WHEEL_QUIET_S`] after. 3DxWare sends them only well past the dead zone (from about a third
+/// of full deflection), never at rest, so a wheel turn with the cap at rest is the user's.
+#[derive(Debug, Default)]
+pub struct WheelGuard {
+    moved_at: Option<f64>,
+}
+
+impl WheelGuard {
+    /// Takes this frame's reading (`now` in seconds) and drops the frame's wheel events if they
+    /// are 3DxWare's.
+    pub fn filter(&mut self, moving: bool, now: f64, events: &mut Vec<egui::Event>) {
+        if moving {
+            self.moved_at = Some(now);
+        }
+        let recent = self.moved_at.is_some_and(|at| (0.0..=WHEEL_QUIET_S).contains(&(now - at)));
+        if recent {
+            events.retain(|e| !matches!(e, egui::Event::MouseWheel { .. } | egui::Event::Zoom(_)));
+        }
+    }
+}
+
+#[cfg(target_arch = "wasm32")]
+pub use browser::SpaceMouse;
+
+#[cfg(target_arch = "wasm32")]
+mod browser {
+    use std::cell::Cell;
+    use std::rc::Rc;
+
+    use solidcraft_ui_egui::SolveApp;
+    use solidcraft_ui_egui::space_mouse::{Axes, DriverMapping, navigate_frame};
+    use wasm_bindgen::JsCast as _;
+    use wasm_bindgen::closure::Closure;
+
+    use super::{WheelGuard, axes, choose, source};
+
+    /// How often the page looks for the cap starting to move while nothing else redraws.
+    const WAKE_MS: i32 = 50;
+
+    /// The 3D mouse the browser lists, if any.
+    fn read() -> Option<Axes> {
+        let pads = web_sys::window()?.navigator().get_gamepads().ok()?;
+        choose(pads.iter().filter_map(|pad| {
+            let pad = pad.dyn_into::<web_sys::Gamepad>().ok().filter(web_sys::Gamepad::connected)?;
+            let source = source(&pad.id())?;
+            let values: Vec<f64> = pad.axes().iter().map(|v| v.as_f64().unwrap_or(f64::NAN)).collect();
+            Some((source, axes(&values)?))
+        }))
+    }
+
+    /// Reads the 3D mouse once per frame and moves the view with it.
+    #[derive(Default)]
+    pub struct SpaceMouse {
+        axes: Axes,
+        /// The previous frame's time and the step since it (seconds).
+        last: Option<f64>,
+        seconds: f64,
+        wheel: WheelGuard,
+        /// Listening for gamepads (from the first frame with navigation on).
+        listening: bool,
+        /// The timer that wakes the app when the cap starts moving runs (from when a 3D mouse
+        /// is first listed).
+        waking: bool,
+        /// Navigation is on (the waker reads it).
+        enabled: Rc<Cell<bool>>,
+    }
+
+    impl SpaceMouse {
+        /// At the start of a frame: reads the cap and drops 3DxWare's emulated wheel from the
+        /// frame's input, before the app sees it.
+        pub fn raw_input_hook(&mut self, ctx: &egui::Context, enabled: bool, raw: &mut egui::RawInput) {
+            let now = raw.time.unwrap_or_else(|| js_sys::Date::now() / 1000.0);
+            self.seconds = self.last.map_or(0.0, |last| now - last);
+            self.last = Some(now);
+            self.enabled.set(enabled);
+            self.axes = Axes::default();
+            if !enabled {
+                return;
+            }
+            if !self.listening {
+                self.listening = true;
+                listen(ctx);
+            }
+            let reading = read();
+            if reading.is_some() && !self.waking {
+                self.waking = wake(ctx, &self.enabled);
+            }
+            // Inside the dead zone is rest: a cap resting just off zero doesn't keep redrawing.
+            self.axes = reading.filter(|axes| axes.moving()).unwrap_or_default();
+            self.wheel.filter(self.axes.moving(), now, &mut raw.events);
+        }
+
+        pub fn logic(&self, app: &mut SolveApp, ctx: &egui::Context) {
+            navigate_frame(app, ctx, DriverMapping::object_mode(), self.axes, self.seconds);
+        }
+    }
+
+    /// A 3D mouse is listed only once it has been moved on the page: redraw then, so the frame
+    /// finds it without waiting for the pointer.
+    fn listen(ctx: &egui::Context) {
+        let Some(window) = web_sys::window() else { return };
+        let ctx = ctx.clone();
+        let on_connect = Closure::<dyn FnMut()>::new(move || ctx.request_repaint());
+        let _ = window.add_event_listener_with_callback("gamepadconnected", on_connect.as_ref().unchecked_ref());
+        // The listener lives as long as the page.
+        on_connect.forget();
+    }
+
+    /// The browser sends no event when a gamepad moves, so a timer looks while the app is idle and
+    /// redraws when the cap starts moving; the frames that follow keep going on their own.
+    fn wake(ctx: &egui::Context, enabled: &Rc<Cell<bool>>) -> bool {
+        let Some(window) = web_sys::window() else { return false };
+        let (ctx, enabled) = (ctx.clone(), Rc::clone(enabled));
+        let tick = Closure::<dyn FnMut()>::new(move || {
+            if enabled.get() && read().is_some_and(Axes::moving) {
+                ctx.request_repaint();
+            }
+        });
+        let started = window.set_interval_with_callback_and_timeout_and_arguments_0(tick.as_ref().unchecked_ref(), WAKE_MS).is_ok();
+        // The timer lives as long as the page.
+        tick.forget();
+        started
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn wheel(dy: f32) -> egui::Event {
+        egui::Event::MouseWheel {
+            unit: egui::MouseWheelUnit::Point,
+            delta: egui::vec2(0.0, dy),
+            modifiers: egui::Modifiers::NONE,
+            phase: egui::TouchPhase::Move,
+        }
+    }
+
+    fn other() -> egui::Event {
+        egui::Event::PointerMoved(egui::pos2(1.0, 2.0))
+    }
+
+    #[test]
+    fn recognises_3d_mice_in_each_browsers_ids() {
+        // As Edge and Firefox list them (Windows 11, SpaceMouse Pro, 3DxWare 10).
+        assert_eq!(source("SpaceMouse Pro (Vendor: 046d Product: c62b)"), Some(Source::Device));
+        assert_eq!(source("Unknown Gamepad (Vendor: beef Product: 046d)"), Some(Source::VirtualJoystick));
+        assert_eq!(source("beef-046d-Unknown Gamepad"), Some(Source::VirtualJoystick));
+        // 3Dconnexion's own vendor id, any product; the older devices under Logitech's.
+        assert_eq!(source("SpaceMouse Compact (Vendor: 256f Product: c635)"), Some(Source::Device));
+        assert_eq!(source("256f-c652-3Dconnexion Universal Receiver"), Some(Source::Device));
+        assert_eq!(source("46d-c626-SpaceNavigator"), Some(Source::Device));
+        assert_eq!(source("SpaceNavigator (STANDARD GAMEPAD Vendor: 046d Product: c626)"), Some(Source::Device));
+        for product in LOGITECH_3D_MICE {
+            assert_eq!(source(&format!("x (Vendor: 046d Product: {product:04x})")), Some(Source::Device));
+            assert_eq!(source(&format!("046d-{product:04X}-x")), Some(Source::Device));
+        }
+    }
+
+    #[test]
+    fn gamepads_and_other_logitech_devices_are_not_3d_mice() {
+        for id in [
+            "Logitech Dual Action (STANDARD GAMEPAD Vendor: 046d Product: c216)",
+            "046d-c21d-Logitech Gamepad F310",
+            "G29 Driving Force Racing Wheel (Vendor: 046d Product: c24f)",
+            "046d-c215-Logitech Extreme 3D",
+            "NuLOOQ navigator (Vendor: 046d Product: c640)",
+            "Xbox 360 Controller (XInput STANDARD GAMEPAD)",
+            "45e-28e-Xbox 360 Wired Controller",
+            "beef-046e-Unknown Gamepad",
+            "beee-046d-Unknown Gamepad",
+            "",
+            "-",
+            "--",
+            "256f-",
+            "256f-c635",
+            "Vendor: 256f",
+            "Vendor: 256f Product: ",
+            "x (Vendor: 256fff Product: c635)",
+            "x (Vendor: zz6f Product: c635)",
+            "12345-c635-x",
+            "256f--x",
+            "SpaceMouse Pro",
+        ] {
+            assert_eq!(source(id), None, "{id:?}");
+        }
+    }
+
+    #[test]
+    fn ids_never_panic() {
+        // Hostile and odd ids: multi-byte text around the markers, markers repeated or cut short.
+        for id in [
+            "Vendor: é Product: ü",
+            "Vendor: Vendor: 256f Product: c635)",
+            "é-ü-ö",
+            "Ⅰ (Vendor: 256f Product: c6Ⅰ)",
+            "\u{0}-\u{0}-\u{0}",
+            "Vendor: 256f Product: c635 Vendor: ",
+        ] {
+            let _ = source(id);
+        }
+        let mut seed = 0x2545_f491_4f6c_dd1d_u64;
+        let alphabet: Vec<char> = "0123456789abcdefABCDEF- ():VendorProductéⅠ\u{0}".chars().collect();
+        for _ in 0..20_000 {
+            let len = (seed % 40) as usize;
+            let id: String = (0..len)
+                .map(|_| {
+                    seed ^= seed << 13;
+                    seed ^= seed >> 7;
+                    seed ^= seed << 17;
+                    alphabet[(seed % alphabet.len() as u64) as usize]
+                })
+                .collect();
+            if let Some(Source::Device) = source(&id) {
+                let (vendor, product) = vendor_product(&id).expect("recognised ids have both");
+                assert!(vendor == THREEDCONNEXION || (vendor == LOGITECH && LOGITECH_3D_MICE.contains(&product)), "{id:?}");
+            }
+        }
+    }
+
+    #[test]
+    fn gamepad_axes_are_the_devices_raw_units() {
+        // Full deflection is the desktop's 350, and the browser's scale keeps the device's steps.
+        let axes = axes(&[1.0, -1.0, 0.5, -0.5, 2.0 / 700.0, 0.0]).expect("six axes");
+        assert_eq!(axes, Axes { translation: [350, -350, 175], rotation: [-175, 1, 0] });
+        for raw in -350_i16..=350 {
+            let value = f64::from(raw) / 350.0;
+            assert_eq!(super::axes(&[value; 6]).map(|a| a.translation[0]), Some(raw));
+        }
+        // Past full deflection is full deflection; anything that isn't a number is rest.
+        let hostile = super::axes(&[f64::NAN, f64::INFINITY, f64::NEG_INFINITY, 1e300, -1e300, f64::MIN_POSITIVE]).expect("six axes");
+        assert_eq!(hostile, Axes { translation: [0, 0, 0], rotation: [350, -350, 0] });
+        // A gamepad with fewer than six axes is not a 3D mouse; extra axes are ignored.
+        assert_eq!(super::axes(&[1.0; 5]), None);
+        assert_eq!(super::axes(&[]), None);
+        assert_eq!(super::axes(&[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0]), Some(Axes::default()));
+    }
+
+    #[test]
+    fn a_device_is_read_before_the_virtual_joystick() {
+        let moving = Axes { translation: [100, 0, 0], rotation: [0; 3] };
+        let other = Axes { translation: [0, 200, 0], rotation: [0; 3] };
+        assert_eq!(choose([(Source::VirtualJoystick, other), (Source::Device, moving)]), Some(moving));
+        assert_eq!(choose([(Source::Device, moving), (Source::VirtualJoystick, other)]), Some(moving));
+        assert_eq!(choose([(Source::VirtualJoystick, other)]), Some(other));
+        // Two devices: the first listed.
+        assert_eq!(choose([(Source::Device, moving), (Source::Device, other)]), Some(moving));
+        assert_eq!(choose([]), None);
+    }
+
+    #[test]
+    fn wheel_turns_are_dropped_while_the_cap_moves_and_kept_at_rest() {
+        let mut guard = WheelGuard::default();
+        // At rest, the wheel is the user's.
+        let mut events = vec![wheel(100.0), other()];
+        guard.filter(false, 10.0, &mut events);
+        assert_eq!(events.len(), 2);
+        // Moving: 3DxWare's wheel (and a pinch zoom) goes; everything else stays.
+        let mut events = vec![wheel(-100.0), other(), egui::Event::Zoom(1.1), wheel(100.0)];
+        guard.filter(true, 11.0, &mut events);
+        assert_eq!(events, vec![other()]);
+        // Just after the cap stops, a queued one still goes.
+        let mut events = vec![wheel(100.0)];
+        guard.filter(false, 11.0 + WHEEL_QUIET_S - 0.01, &mut events);
+        assert!(events.is_empty());
+        // Later, the wheel is the user's again.
+        let mut events = vec![wheel(100.0)];
+        guard.filter(false, 11.0 + WHEEL_QUIET_S + 0.01, &mut events);
+        assert_eq!(events.len(), 1);
+        // A clock that goes back never swallows the user's wheel.
+        let mut events = vec![wheel(100.0)];
+        guard.filter(false, 5.0, &mut events);
+        assert_eq!(events.len(), 1);
+        let mut events = vec![wheel(100.0)];
+        guard.filter(false, f64::NAN, &mut events);
+        assert_eq!(events.len(), 1);
+    }
+}