winit-core:winit: add tablet input support

The API is integrated into the `WindowEvent::Pointer*` API and is
present in form of `TabletTool` variant on corresponding data entries.

For now implemented for Web, Windows, and with limitations for Wayland.

Fixes #99.

Co-authored-by: daxpedda <daxpedda@gmail.com>

winit-wayland/src/seat/mod.rs

@@ -13,6 +13,7 @@ use sctk::seat::pointer::{ThemeSpec, ThemedPointer};
 use sctk::seat::{Capability as SeatCapability, SeatHandler, SeatState};
 use tracing::warn;
 use wayland_protocols::wp::pointer_gestures::zv1::client::zwp_pointer_gesture_pinch_v1::ZwpPointerGesturePinchV1;
+use wayland_protocols::wp::tablet::zv2::client::zwp_tablet_seat_v2::ZwpTabletSeatV2;
 use winit_core::event::WindowEvent;
 use winit_core::keyboard::ModifiersState;
 
@@ -50,6 +51,9 @@ pub struct WinitSeatState {
     /// The text input bound on the seat.
     text_input: Option<Arc<ZwpTextInputV3>>,
 
+    /// The tablet input bound on the seat.
+    tablet: Option<Arc<ZwpTabletSeatV2>>,
+
     /// The relative pointer bound on the seat.
     relative_pointer: Option<ZwpRelativePointerV1>,
 
@@ -156,6 +160,12 @@ impl SeatHandler for WinitState {
                 TextInputData::default(),
             )));
         }
+
+        if let Some(tablet_state) =
+            seat_state.tablet.is_none().then_some(self.tablet_state.as_ref()).flatten()
+        {
+            seat_state.tablet = Some(Arc::new(tablet_state.get_tablet_seat(&seat, queue_handle)));
+        }
     }
 
     fn remove_capability(
@@ -177,6 +187,11 @@ impl SeatHandler for WinitState {
             text_input.destroy();
         }
 
+        // NOTE: figure out when this should actually be destroyed.
+        if let Some(tablet) = seat_state.tablet.take() {
+            tablet.destroy();
+        }
+
         match capability {
             SeatCapability::Touch => {
                 if let Some(touch) = seat_state.touch.take() {

winit-wayland/src/state.rs

@@ -30,6 +30,7 @@ use crate::seat::{
 };
 use crate::types::kwin_blur::KWinBlurManager;
 use crate::types::wp_fractional_scaling::FractionalScalingManager;
+use crate::types::wp_tablet_input_v2::TabletManager;
 use crate::types::wp_viewporter::ViewporterState;
 use crate::types::xdg_activation::XdgActivationState;
 use crate::types::xdg_toplevel_icon_manager::XdgToplevelIconManagerState;
@@ -100,6 +101,9 @@ pub struct WinitState {
     /// Relative pointer.
     pub relative_pointer: Option<RelativePointerState>,
 
+    /// Tablet manager.
+    pub tablet_state: Option<TabletManager>,
+
     /// Pointer constraints to handle pointer locking and confining.
     pub pointer_constraints: Option<Arc<PointerConstraintsState>>,
 
@@ -194,6 +198,7 @@ impl WinitState {
             text_input_state: TextInputState::new(globals, queue_handle).ok(),
 
             relative_pointer: RelativePointerState::new(globals, queue_handle).ok(),
+            tablet_state: TabletManager::new(globals, queue_handle).ok(),
             pointer_constraints: PointerConstraintsState::new(globals, queue_handle)
                 .map(Arc::new)
                 .ok(),

winit-wayland/src/types/mod.rs

@@ -3,6 +3,7 @@
 pub mod cursor;
 pub mod kwin_blur;
 pub mod wp_fractional_scaling;
+pub mod wp_tablet_input_v2;
 pub mod wp_viewporter;
 pub mod xdg_activation;
 pub mod xdg_toplevel_icon_manager;

winit-wayland/src/types/wp_tablet_input_v2.rs

@@ -0,0 +1,343 @@
+//! Handling of wp_tablet_input_v2.
+
+use std::sync::Mutex;
+
+use dpi::LogicalPosition;
+use sctk::compositor::SurfaceData;
+use sctk::globals::GlobalData;
+use sctk::reexports::client::backend::smallvec::SmallVec;
+use sctk::reexports::client::globals::{BindError, GlobalList};
+use sctk::reexports::client::protocol::wl_seat::WlSeat;
+use sctk::reexports::client::protocol::wl_surface::WlSurface;
+use sctk::reexports::client::{
+    delegate_dispatch, event_created_child, Connection, Dispatch, Proxy, QueueHandle, WEnum,
+};
+use sctk::reexports::protocols::wp::tablet::zv2::client::zwp_tablet_manager_v2::ZwpTabletManagerV2;
+use sctk::reexports::protocols::wp::tablet::zv2::client::zwp_tablet_pad_v2::ZwpTabletPadV2;
+use sctk::reexports::protocols::wp::tablet::zv2::client::zwp_tablet_seat_v2::{
+    self, ZwpTabletSeatV2,
+};
+use sctk::reexports::protocols::wp::tablet::zv2::client::zwp_tablet_tool_v2::{
+    ButtonState, Event as ToolEvent, Type as ToolType, ZwpTabletToolV2,
+};
+use sctk::reexports::protocols::wp::tablet::zv2::client::zwp_tablet_v2::ZwpTabletV2;
+use winit_core::event::{
+    ButtonSource, ElementState, Force, PointerKind, PointerSource, TabletToolButton,
+    TabletToolData as CoreTabletToolData, TabletToolKind, TabletToolTilt, WindowEvent,
+};
+
+use crate::state::WinitState;
+
+/// KWin blur manager.
+#[derive(Debug, Clone)]
+pub struct TabletManager {
+    manager: ZwpTabletManagerV2,
+}
+
+impl TabletManager {
+    pub fn new(
+        globals: &GlobalList,
+        queue_handle: &QueueHandle<WinitState>,
+    ) -> Result<Self, BindError> {
+        // Ignore v2 since we are not interested in its events.
+        let manager = globals.bind(queue_handle, 1..=1, GlobalData)?;
+        Ok(Self { manager })
+    }
+
+    pub fn get_tablet_seat(
+        &self,
+        seat: &WlSeat,
+        queue_handle: &QueueHandle<WinitState>,
+    ) -> ZwpTabletSeatV2 {
+        self.manager.get_tablet_seat(seat, queue_handle, ())
+    }
+}
+impl Dispatch<ZwpTabletManagerV2, GlobalData, WinitState> for TabletManager {
+    fn event(
+        _: &mut WinitState,
+        _: &ZwpTabletManagerV2,
+        _: <ZwpTabletManagerV2 as Proxy>::Event,
+        _: &GlobalData,
+        _: &Connection,
+        _: &QueueHandle<WinitState>,
+    ) {
+        unreachable!("no events defined for zwp_tablet_manager_v2");
+    }
+}
+
+impl Dispatch<ZwpTabletManagerV2, (), WinitState> for TabletManager {
+    fn event(
+        _: &mut WinitState,
+        _: &ZwpTabletManagerV2,
+        _: <ZwpTabletManagerV2 as Proxy>::Event,
+        _: &(),
+        _: &Connection,
+        _: &QueueHandle<WinitState>,
+    ) {
+        unreachable!("no events defined for zwp_tablet_manager_v2");
+    }
+}
+
+impl Dispatch<ZwpTabletSeatV2, (), WinitState> for TabletManager {
+    event_created_child!(WinitState, ZwpTabletSeatV2, [
+        zwp_tablet_seat_v2::EVT_TABLET_ADDED_OPCODE => (ZwpTabletV2, Default::default()),
+        zwp_tablet_seat_v2::EVT_TOOL_ADDED_OPCODE => (ZwpTabletToolV2, Default::default()),
+        zwp_tablet_seat_v2::EVT_PAD_ADDED_OPCODE => (ZwpTabletPadV2, Default::default())
+    ]);
+
+    fn event(
+        _: &mut WinitState,
+        _: &ZwpTabletSeatV2,
+        _: <ZwpTabletSeatV2 as Proxy>::Event,
+        _: &(),
+        _: &Connection,
+        _: &QueueHandle<WinitState>,
+    ) {
+    }
+}
+
+impl Dispatch<ZwpTabletToolV2, TabletToolData, WinitState> for TabletManager {
+    fn event(
+        state: &mut WinitState,
+        _: &ZwpTabletToolV2,
+        event: <ZwpTabletToolV2 as Proxy>::Event,
+        data: &TabletToolData,
+        _: &Connection,
+        _: &QueueHandle<WinitState>,
+    ) {
+        let mut data = data.inner.lock().unwrap();
+
+        match event {
+            ToolEvent::Type { tool_type: WEnum::Value(tool_type) } => {
+                data.ty = match tool_type {
+                    ToolType::Pen => TabletToolKind::Pen,
+                    ToolType::Eraser => TabletToolKind::Eraser,
+                    ToolType::Brush => TabletToolKind::Brush,
+                    ToolType::Pencil => TabletToolKind::Pencil,
+                    ToolType::Airbrush => TabletToolKind::Airbrush,
+                    ToolType::Finger => TabletToolKind::Finger,
+                    ToolType::Mouse => TabletToolKind::Mouse,
+                    ToolType::Lens => TabletToolKind::Lens,
+                    _ => return,
+                };
+            },
+            ToolEvent::Capability { .. } => {},
+            ToolEvent::Done => (),
+            ToolEvent::ProximityIn { serial, surface, .. } => {
+                data.pending.push(TabletEvent::Enter { serial, surface });
+            },
+            ToolEvent::ProximityOut => data.pending.push(TabletEvent::Left),
+            ToolEvent::Down { serial } => {
+                let event = TabletEvent::Button {
+                    state: ElementState::Pressed,
+                    serial: Some(serial),
+                    button: TabletToolButton::Contact,
+                };
+
+                data.pending.push(event);
+            },
+            ToolEvent::Up => {
+                let event = TabletEvent::Button {
+                    state: ElementState::Released,
+                    serial: None,
+                    button: TabletToolButton::Contact,
+                };
+
+                data.pending.push(event);
+            },
+            ToolEvent::Tilt { tilt_x, tilt_y } => {
+                data.tool_state.tilt = Some(TabletToolTilt { x: tilt_x as i8, y: tilt_y as i8 });
+            },
+            ToolEvent::Motion { x, y } => {
+                data.position = (x, y).into();
+                data.pending.push(TabletEvent::Moved);
+            },
+            ToolEvent::Pressure { pressure } => {
+                data.tool_state.force = Some(Force::Normalized(pressure as f64 / u16::MAX as f64));
+            },
+            ToolEvent::Rotation { degrees } => {
+                data.tool_state.twist = Some(degrees as u16);
+            },
+            ToolEvent::Button { serial, button, state: WEnum::Value(state) } => {
+                let state = match state {
+                    ButtonState::Released => ElementState::Released,
+                    ButtonState::Pressed => ElementState::Pressed,
+                    _ => return,
+                };
+
+                // Map similar to SDL.
+                let button = match button {
+                    // BTN_STYLUS.
+                    0x14b => TabletToolButton::Contact,
+                    0x14c => TabletToolButton::Barrel,
+                    // BTN_STYLUS3.
+                    0x149 => TabletToolButton::Other(1),
+                    // There's no defined conversion for any of that.
+                    button => TabletToolButton::Other(button as u16),
+                };
+
+                let event = TabletEvent::Button { button, state, serial: Some(serial) };
+                data.pending.push(event);
+            },
+            ToolEvent::Frame { .. } => {
+                let kind = data.ty;
+                for event in std::mem::take(&mut data.pending) {
+                    if let TabletEvent::Enter { surface, serial } = &event {
+                        data.latest_enter_serial = Some(*serial);
+                        data.surface = Some(surface.clone());
+                    }
+
+                    // Handle events only for top-level surface.
+                    let surface = match data
+                        .surface
+                        .as_ref()
+                        .map(|surface| (surface, surface.data::<SurfaceData>()))
+                    {
+                        Some((surface, Some(surface_data)))
+                            if surface_data.parent_surface().is_none() =>
+                        {
+                            surface
+                        },
+                        _ => continue,
+                    };
+
+                    let window_id = crate::make_wid(surface);
+
+                    // Ensure that window exists.
+                    let window = match state.windows.get_mut().get_mut(&window_id) {
+                        Some(window) => window.lock().unwrap(),
+                        None => continue,
+                    };
+
+                    let position = data.position.to_physical(window.scale_factor());
+
+                    let window_event = match event {
+                        TabletEvent::Enter { .. } => WindowEvent::PointerEntered {
+                            device_id: None,
+                            position,
+                            primary: true,
+                            kind: PointerKind::TabletTool(kind),
+                        },
+                        TabletEvent::Moved => WindowEvent::PointerMoved {
+                            device_id: None,
+                            position,
+                            primary: true,
+                            source: PointerSource::TabletTool {
+                                kind,
+                                data: data.tool_state.clone(),
+                            },
+                        },
+                        TabletEvent::Button { button, state, serial } => {
+                            // Update serial if we have it.
+                            if let Some(serial) = serial {
+                                data.latest_button_serial = Some(serial);
+                            }
+
+                            WindowEvent::PointerButton {
+                                device_id: None,
+                                state,
+                                position,
+                                primary: true,
+                                button: ButtonSource::TabletTool {
+                                    kind,
+                                    button,
+                                    data: data.tool_state.clone(),
+                                },
+                            }
+                        },
+                        TabletEvent::Left => WindowEvent::PointerLeft {
+                            device_id: None,
+                            position: Some(position),
+                            primary: true,
+                            kind: PointerKind::TabletTool(kind),
+                        },
+                    };
+
+                    state.events_sink.push_window_event(window_event, window_id);
+
+                    // Clear up the surface after we've processed `Left` event.
+                    if matches!(event, TabletEvent::Left) {
+                        data.surface = None;
+                        data.latest_button_serial = None;
+                        data.latest_enter_serial = None;
+                        data.tool_state = Default::default();
+                    }
+                }
+            },
+            _ => (),
+        }
+    }
+}
+
+#[derive(Debug, Default)]
+struct TabletToolData {
+    inner: Mutex<TabletToolDataInner>,
+}
+
+#[derive(Debug, Default)]
+pub(crate) struct TabletToolDataInner {
+    pub(crate) ty: TabletToolKind,
+
+    /// Core tablet tool data.
+    pub(crate) tool_state: CoreTabletToolData,
+
+    /// Pending events until the `frame` is received.
+    pub(crate) pending: SmallVec<[TabletEvent; 4]>,
+
+    /// Surface the tablet most recently entered.
+    pub(crate) surface: Option<WlSurface>,
+
+    /// Position relative to the surface.
+    pub(crate) position: LogicalPosition<f64>,
+
+    // NOTE: even though we don't utilize serials
+    // right now, track them anyway.
+    /// The serial of the latest enter event for the pointer
+    pub(crate) latest_enter_serial: Option<u32>,
+
+    /// The serial of the latest button event for the pointer
+    pub(crate) latest_button_serial: Option<u32>,
+}
+
+// Due to wayland using logical coordinates,
+// delay the conversion to physical until the dispatch actually happens,
+// so the scaling is applied at the time of actual dispatch, since it
+// can technically change before the `frame` event.
+#[derive(Debug, Clone)]
+pub(crate) enum TabletEvent {
+    Enter { serial: u32, surface: WlSurface },
+    Left,
+    Moved,
+    Button { button: TabletToolButton, state: ElementState, serial: Option<u32> },
+}
+
+impl Dispatch<ZwpTabletV2, (), WinitState> for TabletManager {
+    fn event(
+        _: &mut WinitState,
+        _: &ZwpTabletV2,
+        _: <ZwpTabletV2 as Proxy>::Event,
+        _: &(),
+        _: &Connection,
+        _: &QueueHandle<WinitState>,
+    ) {
+    }
+}
+
+impl Dispatch<ZwpTabletPadV2, (), WinitState> for TabletManager {
+    fn event(
+        _: &mut WinitState,
+        _: &ZwpTabletPadV2,
+        _: <ZwpTabletPadV2 as Proxy>::Event,
+        _: &(),
+        _: &Connection,
+        _: &QueueHandle<WinitState>,
+    ) {
+    }
+}
+
+delegate_dispatch!(WinitState: [ZwpTabletManagerV2: GlobalData] => TabletManager);
+delegate_dispatch!(WinitState: [ZwpTabletManagerV2: ()] => TabletManager);
+delegate_dispatch!(WinitState: [ZwpTabletSeatV2: ()] => TabletManager);
+delegate_dispatch!(WinitState: [ZwpTabletV2: ()] => TabletManager);
+delegate_dispatch!(WinitState: [ZwpTabletToolV2: TabletToolData] => TabletManager);
+delegate_dispatch!(WinitState: [ZwpTabletPadV2: ()] => TabletManager);