#![allow(non_snake_case)] mod runner; use std::{ cell::Cell, collections::VecDeque, ffi::c_void, marker::PhantomData, mem, panic, ptr, rc::Rc, sync::{ atomic::{AtomicU32, Ordering}, mpsc::{self, Receiver, Sender}, Arc, Mutex, MutexGuard, }, time::{Duration, Instant}, }; use once_cell::sync::Lazy; use raw_window_handle::{RawDisplayHandle, WindowsDisplayHandle}; use windows_sys::Win32::{ Devices::HumanInterfaceDevice::MOUSE_MOVE_RELATIVE, Foundation::{BOOL, HANDLE, HWND, LPARAM, LRESULT, POINT, RECT, WPARAM}, Graphics::Gdi::{ GetMonitorInfoW, MonitorFromRect, MonitorFromWindow, RedrawWindow, ScreenToClient, ValidateRect, MONITORINFO, MONITOR_DEFAULTTONULL, RDW_INTERNALPAINT, SC_SCREENSAVE, }, System::{ Ole::RevokeDragDrop, Threading::{GetCurrentThreadId, INFINITE}, }, UI::{ Controls::{HOVER_DEFAULT, WM_MOUSELEAVE}, Input::{ Ime::{GCS_COMPSTR, GCS_RESULTSTR, ISC_SHOWUICOMPOSITIONWINDOW}, KeyboardAndMouse::{ MapVirtualKeyW, ReleaseCapture, SetCapture, TrackMouseEvent, MAPVK_VK_TO_VSC_EX, TME_LEAVE, TRACKMOUSEEVENT, VK_NUMLOCK, VK_SHIFT, }, Pointer::{ POINTER_FLAG_DOWN, POINTER_FLAG_UP, POINTER_FLAG_UPDATE, POINTER_INFO, POINTER_PEN_INFO, POINTER_TOUCH_INFO, }, Touch::{ CloseTouchInputHandle, GetTouchInputInfo, TOUCHEVENTF_DOWN, TOUCHEVENTF_MOVE, TOUCHEVENTF_UP, TOUCHINPUT, }, RAWINPUT, RIM_TYPEKEYBOARD, RIM_TYPEMOUSE, }, WindowsAndMessaging::{ CreateWindowExW, DefWindowProcW, DestroyWindow, DispatchMessageW, GetCursorPos, GetMenu, GetMessageW, KillTimer, LoadCursorW, PeekMessageW, PostMessageW, RegisterClassExW, RegisterWindowMessageA, SetCursor, SetTimer, SetWindowPos, TranslateMessage, CREATESTRUCTW, GIDC_ARRIVAL, GIDC_REMOVAL, GWL_STYLE, GWL_USERDATA, HTCAPTION, HTCLIENT, MINMAXINFO, MNC_CLOSE, MSG, NCCALCSIZE_PARAMS, PM_REMOVE, PT_PEN, PT_TOUCH, RI_KEY_E0, RI_KEY_E1, RI_MOUSE_WHEEL, SC_MINIMIZE, SC_RESTORE, SIZE_MAXIMIZED, SWP_NOACTIVATE, SWP_NOMOVE, SWP_NOSIZE, SWP_NOZORDER, WHEEL_DELTA, WINDOWPOS, WM_CAPTURECHANGED, WM_CLOSE, WM_CREATE, WM_DESTROY, WM_DPICHANGED, WM_ENTERSIZEMOVE, WM_EXITSIZEMOVE, WM_GETMINMAXINFO, WM_IME_COMPOSITION, WM_IME_ENDCOMPOSITION, WM_IME_SETCONTEXT, WM_IME_STARTCOMPOSITION, WM_INPUT, WM_INPUT_DEVICE_CHANGE, WM_KEYDOWN, WM_KEYUP, WM_KILLFOCUS, WM_LBUTTONDOWN, WM_LBUTTONUP, WM_MBUTTONDOWN, WM_MBUTTONUP, WM_MENUCHAR, WM_MOUSEHWHEEL, WM_MOUSEMOVE, WM_MOUSEWHEEL, WM_NCACTIVATE, WM_NCCALCSIZE, WM_NCCREATE, WM_NCDESTROY, WM_NCLBUTTONDOWN, WM_PAINT, WM_POINTERDOWN, WM_POINTERUP, WM_POINTERUPDATE, WM_RBUTTONDOWN, WM_RBUTTONUP, WM_SETCURSOR, WM_SETFOCUS, WM_SETTINGCHANGE, WM_SIZE, WM_SYSCOMMAND, WM_SYSKEYDOWN, WM_SYSKEYUP, WM_TOUCH, WM_WINDOWPOSCHANGED, WM_WINDOWPOSCHANGING, WM_XBUTTONDOWN, WM_XBUTTONUP, WNDCLASSEXW, WS_EX_LAYERED, WS_EX_NOACTIVATE, WS_EX_TOOLWINDOW, WS_EX_TRANSPARENT, WS_OVERLAPPED, WS_POPUP, WS_VISIBLE, }, }, }; use crate::{ dpi::{PhysicalPosition, PhysicalSize}, error::RunLoopError, event::{ DeviceEvent, Event, Force, Ime, InnerSizeWriter, RawKeyEvent, Touch, TouchPhase, WindowEvent, }, event_loop::{ControlFlow, DeviceEvents, EventLoopClosed, EventLoopWindowTarget as RootELW}, keyboard::{KeyCode, ModifiersState}, platform::{pump_events::PumpStatus, scancode::KeyCodeExtScancode}, platform_impl::platform::{ dark_mode::try_theme, dpi::{become_dpi_aware, dpi_to_scale_factor}, drop_handler::FileDropHandler, ime::ImeContext, keyboard::KeyEventBuilder, keyboard_layout::LAYOUT_CACHE, monitor::{self, MonitorHandle}, raw_input, util, window::InitData, window_state::{CursorFlags, ImeState, WindowFlags, WindowState}, wrap_device_id, Fullscreen, WindowId, DEVICE_ID, }, window::WindowId as RootWindowId, }; use runner::{EventLoopRunner, EventLoopRunnerShared}; use self::runner::RunnerState; use super::window::set_skip_taskbar; type GetPointerFrameInfoHistory = unsafe extern "system" fn( pointerId: u32, entriesCount: *mut u32, pointerCount: *mut u32, pointerInfo: *mut POINTER_INFO, ) -> BOOL; type SkipPointerFrameMessages = unsafe extern "system" fn(pointerId: u32) -> BOOL; type GetPointerDeviceRects = unsafe extern "system" fn( device: HANDLE, pointerDeviceRect: *mut RECT, displayRect: *mut RECT, ) -> BOOL; type GetPointerTouchInfo = unsafe extern "system" fn(pointerId: u32, touchInfo: *mut POINTER_TOUCH_INFO) -> BOOL; type GetPointerPenInfo = unsafe extern "system" fn(pointId: u32, penInfo: *mut POINTER_PEN_INFO) -> BOOL; static GET_POINTER_FRAME_INFO_HISTORY: Lazy> = Lazy::new(|| get_function!("user32.dll", GetPointerFrameInfoHistory)); static SKIP_POINTER_FRAME_MESSAGES: Lazy> = Lazy::new(|| get_function!("user32.dll", SkipPointerFrameMessages)); static GET_POINTER_DEVICE_RECTS: Lazy> = Lazy::new(|| get_function!("user32.dll", GetPointerDeviceRects)); static GET_POINTER_TOUCH_INFO: Lazy> = Lazy::new(|| get_function!("user32.dll", GetPointerTouchInfo)); static GET_POINTER_PEN_INFO: Lazy> = Lazy::new(|| get_function!("user32.dll", GetPointerPenInfo)); pub(crate) struct WindowData { pub window_state: Arc>, pub event_loop_runner: EventLoopRunnerShared, pub key_event_builder: KeyEventBuilder, pub _file_drop_handler: Option, pub userdata_removed: Cell, pub recurse_depth: Cell, } impl WindowData { unsafe fn send_event(&self, event: Event) { self.event_loop_runner.send_event(event); } fn window_state_lock(&self) -> MutexGuard<'_, WindowState> { self.window_state.lock().unwrap() } } struct ThreadMsgTargetData { event_loop_runner: EventLoopRunnerShared, user_event_receiver: Receiver, } impl ThreadMsgTargetData { unsafe fn send_event(&self, event: Event) { self.event_loop_runner.send_event(event); } } /// The result of a subclass procedure (the message handling callback) #[derive(Clone, Copy)] pub(crate) enum ProcResult { DefWindowProc(WPARAM), Value(isize), } pub struct EventLoop { thread_msg_sender: Sender, window_target: RootELW, msg_hook: Option bool + 'static>>, } pub(crate) struct PlatformSpecificEventLoopAttributes { pub(crate) any_thread: bool, pub(crate) dpi_aware: bool, pub(crate) msg_hook: Option bool + 'static>>, } impl Default for PlatformSpecificEventLoopAttributes { fn default() -> Self { Self { any_thread: false, dpi_aware: true, msg_hook: None, } } } pub struct EventLoopWindowTarget { thread_id: u32, thread_msg_target: HWND, pub(crate) runner_shared: EventLoopRunnerShared, } impl EventLoop { pub(crate) fn new(attributes: &mut PlatformSpecificEventLoopAttributes) -> Self { let thread_id = unsafe { GetCurrentThreadId() }; if !attributes.any_thread && thread_id != main_thread_id() { panic!( "Initializing the event loop outside of the main thread is a significant \ cross-platform compatibility hazard. If you absolutely need to create an \ EventLoop on a different thread, you can use the \ `EventLoopBuilderExtWindows::any_thread` function." ); } if attributes.dpi_aware { become_dpi_aware(); } let thread_msg_target = create_event_target_window::(); let runner_shared = Rc::new(EventLoopRunner::new(thread_msg_target)); let thread_msg_sender = insert_event_target_window_data::(thread_msg_target, runner_shared.clone()); raw_input::register_all_mice_and_keyboards_for_raw_input( thread_msg_target, Default::default(), ); EventLoop { thread_msg_sender, window_target: RootELW { p: EventLoopWindowTarget { thread_id, thread_msg_target, runner_shared, }, _marker: PhantomData, }, msg_hook: attributes.msg_hook.take(), } } pub fn window_target(&self) -> &RootELW { &self.window_target } pub fn run(mut self, event_handler: F) -> Result<(), RunLoopError> where F: FnMut(Event, &RootELW, &mut ControlFlow), { self.run_ondemand(event_handler) } pub fn run_ondemand(&mut self, mut event_handler: F) -> Result<(), RunLoopError> where F: FnMut(Event, &RootELW, &mut ControlFlow), { { let runner = &self.window_target.p.runner_shared; if runner.state() != RunnerState::Uninitialized { return Err(RunLoopError::AlreadyRunning); } let event_loop_windows_ref = &self.window_target; // # Safety // We make sure to call runner.clear_event_handler() before // returning unsafe { runner.set_event_handler(move |event, control_flow| { event_handler(event, event_loop_windows_ref, control_flow) }); } } let exit_code = loop { if let ControlFlow::ExitWithCode(code) = self.wait_and_dispatch_message(None) { break code; } if let ControlFlow::ExitWithCode(code) = self.dispatch_peeked_messages() { break code; } }; let runner = &self.window_target.p.runner_shared; runner.loop_destroyed(); // # Safety // We assume that this will effectively call `runner.clear_event_handler()` // to meet the safety requirements for calling `runner.set_event_handler()` above. runner.reset_runner(); if exit_code == 0 { Ok(()) } else { Err(RunLoopError::ExitFailure(exit_code)) } } pub fn pump_events(&mut self, timeout: Option, mut event_handler: F) -> PumpStatus where F: FnMut(Event, &RootELW, &mut ControlFlow), { { let runner = &self.window_target.p.runner_shared; let event_loop_windows_ref = &self.window_target; // # Safety // We make sure to call runner.clear_event_handler() before // returning // // Note: we're currently assuming nothing can panic and unwind // to leave the runner in an unsound state with an associated // event handler. unsafe { runner.set_event_handler(move |event, control_flow| { event_handler(event, event_loop_windows_ref, control_flow) }); runner.wakeup(); } } if !matches!( self.wait_and_dispatch_message(timeout), ControlFlow::ExitWithCode(_) ) { self.dispatch_peeked_messages(); } let runner = &self.window_target.p.runner_shared; let status = if let ControlFlow::ExitWithCode(code) = runner.control_flow() { runner.loop_destroyed(); // Immediately reset the internal state for the loop to allow // the loop to be run more than once. runner.reset_runner(); PumpStatus::Exit(code) } else { runner.prepare_wait(); PumpStatus::Continue }; // We wait until we've checked for an exit status before clearing the // application callback, in case we need to dispatch a LoopExiting event // // # Safety // This pairs up with our call to `runner.set_event_handler` and ensures // the application's callback can't be held beyond its lifetime. runner.clear_event_handler(); status } /// Wait for one message and dispatch it, optionally with a timeout fn wait_and_dispatch_message(&mut self, timeout: Option) -> ControlFlow { let start = Instant::now(); let runner = &self.window_target.p.runner_shared; let control_flow_timeout = match runner.control_flow() { ControlFlow::Wait => None, ControlFlow::Poll => Some(Duration::ZERO), ControlFlow::WaitUntil(wait_deadline) => { Some(wait_deadline.saturating_duration_since(start)) } ControlFlow::ExitWithCode(_code) => unreachable!(), }; let timeout = min_timeout(control_flow_timeout, timeout); fn get_msg_with_timeout(msg: &mut MSG, timeout: Option) -> PumpStatus { unsafe { // A timeout of None means wait indefinitely (so we don't need to call SetTimer) let timer_id = timeout.map(|timeout| SetTimer(0, 0, dur2timeout(timeout), None)); let get_status = GetMessageW(msg, 0, 0, 0); if let Some(timer_id) = timer_id { KillTimer(0, timer_id); } // A return value of 0 implies `WM_QUIT` if get_status == 0 { PumpStatus::Exit(0) } else { PumpStatus::Continue } } } /// Fetch the next MSG either via PeekMessage or GetMessage depending on whether the /// requested timeout is `ZERO` (and so we don't want to block) /// /// Returns `None` if if no MSG was read, else a `Continue` or `Exit` status fn wait_for_msg(msg: &mut MSG, timeout: Option) -> Option { if timeout == Some(Duration::ZERO) { unsafe { if PeekMessageW(msg, 0, 0, 0, PM_REMOVE) != 0 { Some(PumpStatus::Continue) } else { None } } } else { Some(get_msg_with_timeout(msg, timeout)) } } // We aim to be consistent with the MacOS backend which has a RunLoop // observer that will dispatch AboutToWait when about to wait for // events, and NewEvents after the RunLoop wakes up. // // We emulate similar behaviour by treating `GetMessage` as our wait // point and wake up point (when it returns) and we drain all other // pending messages via `PeekMessage` until we come back to "wait" via // `GetMessage` // runner.prepare_wait(); // # Safety // The Windows API has no documented requirement for bitwise // initializing a `MSG` struct (it can be uninitialized memory for the C // API) and there's no API to construct or initialize a `MSG`. This // is the simplest way avoid unitialized memory in Rust let mut msg = unsafe { mem::zeroed() }; let msg_status = wait_for_msg(&mut msg, timeout); // Before we potentially exit, make sure to consistently emit an event for the wake up runner.wakeup(); match msg_status { None => {} // No MSG to dispatch Some(PumpStatus::Exit(code)) => { runner.set_exit_control_flow(code); return runner.control_flow(); } Some(PumpStatus::Continue) => { unsafe { let handled = if let Some(callback) = self.msg_hook.as_deref_mut() { callback(&mut msg as *mut _ as *mut _) } else { false }; if !handled { TranslateMessage(&msg); DispatchMessageW(&msg); } } if let Err(payload) = runner.take_panic_error() { runner.reset_runner(); panic::resume_unwind(payload); } } } runner.control_flow() } /// Dispatch all queued messages via `PeekMessageW` fn dispatch_peeked_messages(&mut self) -> ControlFlow { let runner = &self.window_target.p.runner_shared; // We generally want to continue dispatching all pending messages // but we also allow dispatching to be interrupted as a means to // ensure the `pump_events` won't indefinitely block an external // event loop if there are too many pending events. This interrupt // flag will be set after dispatching `RedrawRequested` events. runner.interrupt_msg_dispatch.set(false); // # Safety // The Windows API has no documented requirement for bitwise // initializing a `MSG` struct (it can be uninitialized memory for the C // API) and there's no API to construct or initialize a `MSG`. This // is the simplest way avoid unitialized memory in Rust let mut msg = unsafe { mem::zeroed() }; let mut control_flow = runner.control_flow(); loop { unsafe { if PeekMessageW(&mut msg, 0, 0, 0, PM_REMOVE) == false.into() { break; } let handled = if let Some(callback) = self.msg_hook.as_deref_mut() { callback(&mut msg as *mut _ as *mut _) } else { false }; if !handled { TranslateMessage(&msg); DispatchMessageW(&msg); } } if let Err(payload) = runner.take_panic_error() { runner.reset_runner(); panic::resume_unwind(payload); } control_flow = runner.control_flow(); if let ControlFlow::ExitWithCode(_code) = control_flow { break; } if runner.interrupt_msg_dispatch.get() { break; } } control_flow } pub fn create_proxy(&self) -> EventLoopProxy { EventLoopProxy { target_window: self.window_target.p.thread_msg_target, event_send: self.thread_msg_sender.clone(), } } } impl EventLoopWindowTarget { #[inline(always)] pub(crate) fn create_thread_executor(&self) -> EventLoopThreadExecutor { EventLoopThreadExecutor { thread_id: self.thread_id, target_window: self.thread_msg_target, } } // TODO: Investigate opportunities for caching pub fn available_monitors(&self) -> VecDeque { monitor::available_monitors() } pub fn primary_monitor(&self) -> Option { let monitor = monitor::primary_monitor(); Some(monitor) } pub fn raw_display_handle(&self) -> RawDisplayHandle { RawDisplayHandle::Windows(WindowsDisplayHandle::empty()) } pub fn listen_device_events(&self, allowed: DeviceEvents) { raw_input::register_all_mice_and_keyboards_for_raw_input(self.thread_msg_target, allowed); } } /// Returns the id of the main thread. /// /// Windows has no real API to check if the current executing thread is the "main thread", unlike /// macOS. /// /// Windows will let us look up the current thread's id, but there's no API that lets us check what /// the id of the main thread is. We would somehow need to get the main thread's id before a /// developer could spin off any other threads inside of the main entrypoint in order to emulate the /// capabilities of other platforms. /// /// We can get the id of the main thread by using CRT initialization. CRT initialization can be used /// to setup global state within a program. The OS will call a list of function pointers which /// assign values to a static variable. To have get a hold of the main thread id, we need to place /// our function pointer inside of the `.CRT$XCU` section so it is called before the main /// entrypoint. /// /// Full details of CRT initialization can be found here: /// fn main_thread_id() -> u32 { static mut MAIN_THREAD_ID: u32 = 0; /// Function pointer used in CRT initialization section to set the above static field's value. // Mark as used so this is not removable. #[used] #[allow(non_upper_case_globals)] // Place the function pointer inside of CRT initialization section so it is loaded before // main entrypoint. // // See: https://doc.rust-lang.org/stable/reference/abi.html#the-link_section-attribute #[link_section = ".CRT$XCU"] static INIT_MAIN_THREAD_ID: unsafe fn() = { unsafe fn initer() { MAIN_THREAD_ID = GetCurrentThreadId(); } initer }; unsafe { MAIN_THREAD_ID } } /// Returns the minimum `Option`, taking into account that `None` /// equates to an infinite timeout, not a zero timeout (so can't just use /// `Option::min`) fn min_timeout(a: Option, b: Option) -> Option { a.map_or(b, |a_timeout| { b.map_or(Some(a_timeout), |b_timeout| Some(a_timeout.min(b_timeout))) }) } // Implementation taken from https://github.com/rust-lang/rust/blob/db5476571d9b27c862b95c1e64764b0ac8980e23/src/libstd/sys/windows/mod.rs fn dur2timeout(dur: Duration) -> u32 { // Note that a duration is a (u64, u32) (seconds, nanoseconds) pair, and the // timeouts in windows APIs are typically u32 milliseconds. To translate, we // have two pieces to take care of: // // * Nanosecond precision is rounded up // * Greater than u32::MAX milliseconds (50 days) is rounded up to INFINITE // (never time out). dur.as_secs() .checked_mul(1000) .and_then(|ms| ms.checked_add((dur.subsec_nanos() as u64) / 1_000_000)) .and_then(|ms| { if dur.subsec_nanos() % 1_000_000 > 0 { ms.checked_add(1) } else { Some(ms) } }) .map(|ms| { if ms > u32::MAX as u64 { INFINITE } else { ms as u32 } }) .unwrap_or(INFINITE) } impl Drop for EventLoop { fn drop(&mut self) { unsafe { DestroyWindow(self.window_target.p.thread_msg_target); } } } pub(crate) struct EventLoopThreadExecutor { thread_id: u32, target_window: HWND, } unsafe impl Send for EventLoopThreadExecutor {} unsafe impl Sync for EventLoopThreadExecutor {} impl EventLoopThreadExecutor { /// Check to see if we're in the parent event loop's thread. pub(super) fn in_event_loop_thread(&self) -> bool { let cur_thread_id = unsafe { GetCurrentThreadId() }; self.thread_id == cur_thread_id } /// Executes a function in the event loop thread. If we're already in the event loop thread, /// we just call the function directly. /// /// The `Inserted` can be used to inject a `WindowState` for the callback to use. The state is /// removed automatically if the callback receives a `WM_CLOSE` message for the window. /// /// Note that if you are using this to change some property of a window and updating /// `WindowState` then you should call this within the lock of `WindowState`. Otherwise the /// events may be sent to the other thread in different order to the one in which you set /// `WindowState`, leaving them out of sync. /// /// Note that we use a FnMut instead of a FnOnce because we're too lazy to create an equivalent /// to the unstable FnBox. pub(super) fn execute_in_thread(&self, mut function: F) where F: FnMut() + Send + 'static, { unsafe { if self.in_event_loop_thread() { function(); } else { // We double-box because the first box is a fat pointer. let boxed2: ThreadExecFn = Box::new(Box::new(function)); let raw = Box::into_raw(boxed2); let res = PostMessageW(self.target_window, EXEC_MSG_ID.get(), raw as usize, 0); assert!( res != false.into(), "PostMessage failed; is the messages queue full?" ); } } } } type ThreadExecFn = Box>; pub struct EventLoopProxy { target_window: HWND, event_send: Sender, } unsafe impl Send for EventLoopProxy {} impl Clone for EventLoopProxy { fn clone(&self) -> Self { Self { target_window: self.target_window, event_send: self.event_send.clone(), } } } impl EventLoopProxy { pub fn send_event(&self, event: T) -> Result<(), EventLoopClosed> { unsafe { if PostMessageW(self.target_window, USER_EVENT_MSG_ID.get(), 0, 0) != false.into() { self.event_send.send(event).ok(); Ok(()) } else { Err(EventLoopClosed(event)) } } } } /// A lazily-initialized window message ID. pub struct LazyMessageId { /// The ID. id: AtomicU32, /// The name of the message. name: &'static str, } /// An invalid custom window ID. const INVALID_ID: u32 = 0x0; impl LazyMessageId { /// Create a new `LazyId`. const fn new(name: &'static str) -> Self { Self { id: AtomicU32::new(INVALID_ID), name, } } /// Get the message ID. pub fn get(&self) -> u32 { // Load the ID. let id = self.id.load(Ordering::Relaxed); if id != INVALID_ID { return id; } // Register the message. // SAFETY: We are sure that the pointer is a valid C string ending with '\0'. assert!(self.name.ends_with('\0')); let new_id = unsafe { RegisterWindowMessageA(self.name.as_ptr()) }; assert_ne!( new_id, 0, "RegisterWindowMessageA returned zero for '{}': {}", self.name, std::io::Error::last_os_error() ); // Store the new ID. Since `RegisterWindowMessageA` returns the same value for any given string, // the target value will always either be a). `INVALID_ID` or b). the correct ID. Therefore a // compare-and-swap operation here (or really any consideration) is never necessary. self.id.store(new_id, Ordering::Relaxed); new_id } } // Message sent by the `EventLoopProxy` when we want to wake up the thread. // WPARAM and LPARAM are unused. static USER_EVENT_MSG_ID: LazyMessageId = LazyMessageId::new("Winit::WakeupMsg\0"); // Message sent when we want to execute a closure in the thread. // WPARAM contains a Box> that must be retrieved with `Box::from_raw`, // and LPARAM is unused. static EXEC_MSG_ID: LazyMessageId = LazyMessageId::new("Winit::ExecMsg\0"); // Message sent by a `Window` when it wants to be destroyed by the main thread. // WPARAM and LPARAM are unused. pub static DESTROY_MSG_ID: LazyMessageId = LazyMessageId::new("Winit::DestroyMsg\0"); // WPARAM is a bool specifying the `WindowFlags::MARKER_RETAIN_STATE_ON_SIZE` flag. See the // documentation in the `window_state` module for more information. pub static SET_RETAIN_STATE_ON_SIZE_MSG_ID: LazyMessageId = LazyMessageId::new("Winit::SetRetainMaximized\0"); static THREAD_EVENT_TARGET_WINDOW_CLASS: Lazy> = Lazy::new(|| util::encode_wide("Winit Thread Event Target")); /// When the taskbar is created, it registers a message with the "TaskbarCreated" string and then broadcasts this message to all top-level windows /// pub static TASKBAR_CREATED: LazyMessageId = LazyMessageId::new("TaskbarCreated\0"); fn create_event_target_window() -> HWND { use windows_sys::Win32::UI::WindowsAndMessaging::CS_HREDRAW; use windows_sys::Win32::UI::WindowsAndMessaging::CS_VREDRAW; unsafe { let class = WNDCLASSEXW { cbSize: mem::size_of::() as u32, style: CS_HREDRAW | CS_VREDRAW, lpfnWndProc: Some(thread_event_target_callback::), cbClsExtra: 0, cbWndExtra: 0, hInstance: util::get_instance_handle(), hIcon: 0, hCursor: 0, // must be null in order for cursor state to work properly hbrBackground: 0, lpszMenuName: ptr::null(), lpszClassName: THREAD_EVENT_TARGET_WINDOW_CLASS.as_ptr(), hIconSm: 0, }; RegisterClassExW(&class); } unsafe { let window = CreateWindowExW( WS_EX_NOACTIVATE | WS_EX_TRANSPARENT | WS_EX_LAYERED // WS_EX_TOOLWINDOW prevents this window from ever showing up in the taskbar, which // we want to avoid. If you remove this style, this window won't show up in the // taskbar *initially*, but it can show up at some later point. This can sometimes // happen on its own after several hours have passed, although this has proven // difficult to reproduce. Alternatively, it can be manually triggered by killing // `explorer.exe` and then starting the process back up. // It is unclear why the bug is triggered by waiting for several hours. | WS_EX_TOOLWINDOW, THREAD_EVENT_TARGET_WINDOW_CLASS.as_ptr(), ptr::null(), WS_OVERLAPPED, 0, 0, 0, 0, 0, 0, util::get_instance_handle(), ptr::null(), ); super::set_window_long( window, GWL_STYLE, // The window technically has to be visible to receive WM_PAINT messages (which are used // for delivering events during resizes), but it isn't displayed to the user because of // the LAYERED style. (WS_VISIBLE | WS_POPUP) as isize, ); window } } fn insert_event_target_window_data( thread_msg_target: HWND, event_loop_runner: EventLoopRunnerShared, ) -> Sender { let (tx, rx) = mpsc::channel(); let userdata = ThreadMsgTargetData { event_loop_runner, user_event_receiver: rx, }; let input_ptr = Box::into_raw(Box::new(userdata)); unsafe { super::set_window_long(thread_msg_target, GWL_USERDATA, input_ptr as isize) }; tx } /// Capture mouse input, allowing `window` to receive mouse events when the cursor is outside of /// the window. unsafe fn capture_mouse(window: HWND, window_state: &mut WindowState) { window_state.mouse.capture_count += 1; SetCapture(window); } /// Release mouse input, stopping windows on this thread from receiving mouse input when the cursor /// is outside the window. unsafe fn release_mouse(mut window_state: MutexGuard<'_, WindowState>) { window_state.mouse.capture_count = window_state.mouse.capture_count.saturating_sub(1); if window_state.mouse.capture_count == 0 { // ReleaseCapture() causes a WM_CAPTURECHANGED where we lock the window_state. drop(window_state); ReleaseCapture(); } } fn normalize_pointer_pressure(pressure: u32) -> Option { match pressure { 1..=1024 => Some(Force::Normalized(pressure as f64 / 1024.0)), _ => None, } } /// Emit a `ModifiersChanged` event whenever modifiers have changed. /// Returns the current modifier state fn update_modifiers(window: HWND, userdata: &WindowData) { use crate::event::WindowEvent::ModifiersChanged; let modifiers = { let mut layouts = LAYOUT_CACHE.lock().unwrap(); layouts.get_agnostic_mods() }; let mut window_state = userdata.window_state.lock().unwrap(); if window_state.modifiers_state != modifiers { window_state.modifiers_state = modifiers; // Drop lock drop(window_state); unsafe { userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: ModifiersChanged(modifiers.into()), }); } } } unsafe fn gain_active_focus(window: HWND, userdata: &WindowData) { use crate::event::WindowEvent::Focused; update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: Focused(true), }); } unsafe fn lose_active_focus(window: HWND, userdata: &WindowData) { use crate::event::WindowEvent::{Focused, ModifiersChanged}; userdata.window_state_lock().modifiers_state = ModifiersState::empty(); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: ModifiersChanged(ModifiersState::empty().into()), }); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: Focused(false), }); } /// Any window whose callback is configured to this function will have its events propagated /// through the events loop of the thread the window was created in. // // This is the callback that is called by `DispatchMessage` in the events loop. // // Returning 0 tells the Win32 API that the message has been processed. // FIXME: detect WM_DWMCOMPOSITIONCHANGED and call DwmEnableBlurBehindWindow if necessary pub(super) unsafe extern "system" fn public_window_callback( window: HWND, msg: u32, wparam: WPARAM, lparam: LPARAM, ) -> LRESULT { let userdata = super::get_window_long(window, GWL_USERDATA); let userdata_ptr = match (userdata, msg) { (0, WM_NCCREATE) => { let createstruct = &mut *(lparam as *mut CREATESTRUCTW); let initdata = &mut *(createstruct.lpCreateParams as *mut InitData<'_, T>); let result = match initdata.on_nccreate(window) { Some(userdata) => { super::set_window_long(window, GWL_USERDATA, userdata as _); DefWindowProcW(window, msg, wparam, lparam) } None => -1, // failed to create the window }; return result; } // Getting here should quite frankly be impossible, // but we'll make window creation fail here just in case. (0, WM_CREATE) => return -1, (_, WM_CREATE) => { let createstruct = &mut *(lparam as *mut CREATESTRUCTW); let initdata = createstruct.lpCreateParams; let initdata = &mut *(initdata as *mut InitData<'_, T>); initdata.on_create(); return DefWindowProcW(window, msg, wparam, lparam); } (0, _) => return DefWindowProcW(window, msg, wparam, lparam), _ => userdata as *mut WindowData, }; let (result, userdata_removed, recurse_depth) = { let userdata = &*(userdata_ptr); userdata.recurse_depth.set(userdata.recurse_depth.get() + 1); let result = public_window_callback_inner(window, msg, wparam, lparam, userdata); let userdata_removed = userdata.userdata_removed.get(); let recurse_depth = userdata.recurse_depth.get() - 1; userdata.recurse_depth.set(recurse_depth); (result, userdata_removed, recurse_depth) }; if userdata_removed && recurse_depth == 0 { drop(Box::from_raw(userdata_ptr)); } result } unsafe fn public_window_callback_inner( window: HWND, msg: u32, wparam: WPARAM, lparam: LPARAM, userdata: &WindowData, ) -> LRESULT { let mut result = ProcResult::DefWindowProc(wparam); // Send new modifiers before sending key events. let mods_changed_callback = || match msg { WM_KEYDOWN | WM_SYSKEYDOWN | WM_KEYUP | WM_SYSKEYUP => { update_modifiers(window, userdata); result = ProcResult::Value(0); } _ => (), }; userdata .event_loop_runner .catch_unwind(mods_changed_callback) .unwrap_or_else(|| result = ProcResult::Value(-1)); let keyboard_callback = || { use crate::event::WindowEvent::KeyboardInput; let events = userdata .key_event_builder .process_message(window, msg, wparam, lparam, &mut result); for event in events { userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: KeyboardInput { device_id: DEVICE_ID, event: event.event, is_synthetic: event.is_synthetic, }, }); } }; userdata .event_loop_runner .catch_unwind(keyboard_callback) .unwrap_or_else(|| result = ProcResult::Value(-1)); // I decided to bind the closure to `callback` and pass it to catch_unwind rather than passing // the closure to catch_unwind directly so that the match body indendation wouldn't change and // the git blame and history would be preserved. let callback = || match msg { WM_NCCALCSIZE => { let window_flags = userdata.window_state_lock().window_flags; if wparam == 0 || window_flags.contains(WindowFlags::MARKER_DECORATIONS) { result = ProcResult::DefWindowProc(wparam); return; } let params = &mut *(lparam as *mut NCCALCSIZE_PARAMS); if util::is_maximized(window) { // Limit the window size when maximized to the current monitor. // Otherwise it would include the non-existent decorations. // // Use `MonitorFromRect` instead of `MonitorFromWindow` to select // the correct monitor here. // See https://github.com/MicrosoftEdge/WebView2Feedback/issues/2549 let monitor = MonitorFromRect(¶ms.rgrc[0], MONITOR_DEFAULTTONULL); if let Ok(monitor_info) = monitor::get_monitor_info(monitor) { params.rgrc[0] = monitor_info.monitorInfo.rcWork; } } else if window_flags.contains(WindowFlags::MARKER_UNDECORATED_SHADOW) { // Extend the client area to cover the whole non-client area. // https://docs.microsoft.com/en-us/windows/win32/winmsg/wm-nccalcsize#remarks // // HACK(msiglreith): To add the drop shadow we slightly tweak the non-client area. // This leads to a small black 1px border on the top. Adding a margin manually // on all 4 borders would result in the caption getting drawn by the DWM. // // Another option would be to allow the DWM to paint inside the client area. // Unfortunately this results in janky resize behavior, where the compositor is // ahead of the window surface. Currently, there seems no option to achieve this // with the Windows API. params.rgrc[0].top += 1; params.rgrc[0].bottom += 1; } result = ProcResult::Value(0); } WM_ENTERSIZEMOVE => { userdata .window_state_lock() .set_window_flags_in_place(|f| f.insert(WindowFlags::MARKER_IN_SIZE_MOVE)); result = ProcResult::Value(0); } WM_EXITSIZEMOVE => { let mut state = userdata.window_state_lock(); if state.dragging { state.dragging = false; PostMessageW(window, WM_LBUTTONUP, 0, lparam); } state.set_window_flags_in_place(|f| f.remove(WindowFlags::MARKER_IN_SIZE_MOVE)); result = ProcResult::Value(0); } WM_NCLBUTTONDOWN => { if wparam == HTCAPTION as _ { PostMessageW(window, WM_MOUSEMOVE, 0, lparam); } result = ProcResult::DefWindowProc(wparam); } WM_CLOSE => { use crate::event::WindowEvent::CloseRequested; userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: CloseRequested, }); result = ProcResult::Value(0); } WM_DESTROY => { use crate::event::WindowEvent::Destroyed; RevokeDragDrop(window); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: Destroyed, }); result = ProcResult::Value(0); } WM_NCDESTROY => { super::set_window_long(window, GWL_USERDATA, 0); userdata.userdata_removed.set(true); result = ProcResult::Value(0); } WM_PAINT => { if userdata.event_loop_runner.should_buffer() { // this branch can happen in response to `UpdateWindow`, if win32 decides to // redraw the window outside the normal flow of the event loop. RedrawWindow(window, ptr::null(), 0, RDW_INTERNALPAINT); } else { userdata.send_event(Event::RedrawRequested(RootWindowId(WindowId(window)))); } result = ProcResult::DefWindowProc(wparam); } WM_WINDOWPOSCHANGING => { let mut window_state = userdata.window_state_lock(); if let Some(ref mut fullscreen) = window_state.fullscreen { let window_pos = &mut *(lparam as *mut WINDOWPOS); let new_rect = RECT { left: window_pos.x, top: window_pos.y, right: window_pos.x + window_pos.cx, bottom: window_pos.y + window_pos.cy, }; const NOMOVE_OR_NOSIZE: u32 = SWP_NOMOVE | SWP_NOSIZE; let new_rect = if window_pos.flags & NOMOVE_OR_NOSIZE != 0 { let cur_rect = util::WindowArea::Outer.get_rect(window) .expect("Unexpected GetWindowRect failure; please report this error to https://github.com/rust-windowing/winit"); match window_pos.flags & NOMOVE_OR_NOSIZE { NOMOVE_OR_NOSIZE => None, SWP_NOMOVE => Some(RECT { left: cur_rect.left, top: cur_rect.top, right: cur_rect.left + window_pos.cx, bottom: cur_rect.top + window_pos.cy, }), SWP_NOSIZE => Some(RECT { left: window_pos.x, top: window_pos.y, right: window_pos.x - cur_rect.left + cur_rect.right, bottom: window_pos.y - cur_rect.top + cur_rect.bottom, }), _ => unreachable!(), } } else { Some(new_rect) }; if let Some(new_rect) = new_rect { let new_monitor = MonitorFromRect(&new_rect, MONITOR_DEFAULTTONULL); match fullscreen { Fullscreen::Borderless(ref mut fullscreen_monitor) => { if new_monitor != 0 && fullscreen_monitor .as_ref() .map(|monitor| new_monitor != monitor.hmonitor()) .unwrap_or(true) { if let Ok(new_monitor_info) = monitor::get_monitor_info(new_monitor) { let new_monitor_rect = new_monitor_info.monitorInfo.rcMonitor; window_pos.x = new_monitor_rect.left; window_pos.y = new_monitor_rect.top; window_pos.cx = new_monitor_rect.right - new_monitor_rect.left; window_pos.cy = new_monitor_rect.bottom - new_monitor_rect.top; } *fullscreen_monitor = Some(MonitorHandle::new(new_monitor)); } } Fullscreen::Exclusive(ref video_mode) => { let old_monitor = video_mode.monitor.hmonitor(); if let Ok(old_monitor_info) = monitor::get_monitor_info(old_monitor) { let old_monitor_rect = old_monitor_info.monitorInfo.rcMonitor; window_pos.x = old_monitor_rect.left; window_pos.y = old_monitor_rect.top; window_pos.cx = old_monitor_rect.right - old_monitor_rect.left; window_pos.cy = old_monitor_rect.bottom - old_monitor_rect.top; } } } } } result = ProcResult::Value(0); } // WM_MOVE supplies client area positions, so we send Moved here instead. WM_WINDOWPOSCHANGED => { use crate::event::WindowEvent::Moved; let windowpos = lparam as *const WINDOWPOS; if (*windowpos).flags & SWP_NOMOVE != SWP_NOMOVE { let physical_position = PhysicalPosition::new((*windowpos).x, (*windowpos).y); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: Moved(physical_position), }); } // This is necessary for us to still get sent WM_SIZE. result = ProcResult::DefWindowProc(wparam); } WM_SIZE => { use crate::event::WindowEvent::Resized; let w = super::loword(lparam as u32) as u32; let h = super::hiword(lparam as u32) as u32; let physical_size = PhysicalSize::new(w, h); let event = Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: Resized(physical_size), }; { let mut w = userdata.window_state_lock(); // See WindowFlags::MARKER_RETAIN_STATE_ON_SIZE docs for info on why this `if` check exists. if !w .window_flags() .contains(WindowFlags::MARKER_RETAIN_STATE_ON_SIZE) { let maximized = wparam == SIZE_MAXIMIZED as usize; w.set_window_flags_in_place(|f| f.set(WindowFlags::MAXIMIZED, maximized)); } } userdata.send_event(event); result = ProcResult::Value(0); } WM_MENUCHAR => { result = ProcResult::Value((MNC_CLOSE << 16) as isize); } WM_IME_STARTCOMPOSITION => { let ime_allowed = userdata.window_state_lock().ime_allowed; if ime_allowed { userdata.window_state_lock().ime_state = ImeState::Enabled; userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Enabled), }); } result = ProcResult::DefWindowProc(wparam); } WM_IME_COMPOSITION => { let ime_allowed_and_composing = { let w = userdata.window_state_lock(); w.ime_allowed && w.ime_state != ImeState::Disabled }; // Windows Hangul IME sends WM_IME_COMPOSITION after WM_IME_ENDCOMPOSITION, so // check whether composing. if ime_allowed_and_composing { let ime_context = ImeContext::current(window); if lparam == 0 { userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Preedit(String::new(), None)), }); } // Google Japanese Input and ATOK have both flags, so // first, receive composing result if exist. if (lparam as u32 & GCS_RESULTSTR) != 0 { if let Some(text) = ime_context.get_composed_text() { userdata.window_state_lock().ime_state = ImeState::Enabled; userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Preedit(String::new(), None)), }); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Commit(text)), }); } } // Next, receive preedit range for next composing if exist. if (lparam as u32 & GCS_COMPSTR) != 0 { if let Some((text, first, last)) = ime_context.get_composing_text_and_cursor() { userdata.window_state_lock().ime_state = ImeState::Preedit; let cursor_range = first.map(|f| (f, last.unwrap_or(f))); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Preedit(text, cursor_range)), }); } } } // Not calling DefWindowProc to hide composing text drawn by IME. result = ProcResult::Value(0); } WM_IME_ENDCOMPOSITION => { let ime_allowed_or_composing = { let w = userdata.window_state_lock(); w.ime_allowed || w.ime_state != ImeState::Disabled }; if ime_allowed_or_composing { if userdata.window_state_lock().ime_state == ImeState::Preedit { // Windows Hangul IME sends WM_IME_COMPOSITION after WM_IME_ENDCOMPOSITION, so // trying receiving composing result and commit if exists. let ime_context = ImeContext::current(window); if let Some(text) = ime_context.get_composed_text() { userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Preedit(String::new(), None)), }); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Commit(text)), }); } } userdata.window_state_lock().ime_state = ImeState::Disabled; userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Ime(Ime::Disabled), }); } result = ProcResult::DefWindowProc(wparam); } WM_IME_SETCONTEXT => { // Hide composing text drawn by IME. let wparam = wparam & (!ISC_SHOWUICOMPOSITIONWINDOW as usize); result = ProcResult::DefWindowProc(wparam); } // this is necessary for us to maintain minimize/restore state WM_SYSCOMMAND => { if wparam == SC_RESTORE as usize { let mut w = userdata.window_state_lock(); w.set_window_flags_in_place(|f| f.set(WindowFlags::MINIMIZED, false)); } if wparam == SC_MINIMIZE as usize { let mut w = userdata.window_state_lock(); w.set_window_flags_in_place(|f| f.set(WindowFlags::MINIMIZED, true)); } // Send `WindowEvent::Minimized` here if we decide to implement one if wparam == SC_SCREENSAVE as usize { let window_state = userdata.window_state_lock(); if window_state.fullscreen.is_some() { result = ProcResult::Value(0); return; } } result = ProcResult::DefWindowProc(wparam); } WM_MOUSEMOVE => { use crate::event::WindowEvent::{CursorEntered, CursorMoved}; let mouse_was_outside_window = { let mut w = userdata.window_state_lock(); let was_outside_window = !w.mouse.cursor_flags().contains(CursorFlags::IN_WINDOW); w.mouse .set_cursor_flags(window, |f| f.set(CursorFlags::IN_WINDOW, true)) .ok(); was_outside_window }; if mouse_was_outside_window { userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: CursorEntered { device_id: DEVICE_ID, }, }); // Calling TrackMouseEvent in order to receive mouse leave events. TrackMouseEvent(&mut TRACKMOUSEEVENT { cbSize: mem::size_of::() as u32, dwFlags: TME_LEAVE, hwndTrack: window, dwHoverTime: HOVER_DEFAULT, }); } let x = super::get_x_lparam(lparam as u32) as f64; let y = super::get_y_lparam(lparam as u32) as f64; let position = PhysicalPosition::new(x, y); let cursor_moved; { // handle spurious WM_MOUSEMOVE messages // see https://devblogs.microsoft.com/oldnewthing/20031001-00/?p=42343 // and http://debugandconquer.blogspot.com/2015/08/the-cause-of-spurious-mouse-move.html let mut w = userdata.window_state_lock(); cursor_moved = w.mouse.last_position != Some(position); w.mouse.last_position = Some(position); } if cursor_moved { update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: CursorMoved { device_id: DEVICE_ID, position, }, }); } result = ProcResult::Value(0); } WM_MOUSELEAVE => { use crate::event::WindowEvent::CursorLeft; { let mut w = userdata.window_state_lock(); w.mouse .set_cursor_flags(window, |f| f.set(CursorFlags::IN_WINDOW, false)) .ok(); } userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: CursorLeft { device_id: DEVICE_ID, }, }); result = ProcResult::Value(0); } WM_MOUSEWHEEL => { use crate::event::MouseScrollDelta::LineDelta; let value = (wparam >> 16) as i16; let value = value as i32; let value = value as f32 / WHEEL_DELTA as f32; update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::MouseWheel { device_id: DEVICE_ID, delta: LineDelta(0.0, value), phase: TouchPhase::Moved, }, }); result = ProcResult::Value(0); } WM_MOUSEHWHEEL => { use crate::event::MouseScrollDelta::LineDelta; let value = (wparam >> 16) as i16; let value = value as i32; let value = -value as f32 / WHEEL_DELTA as f32; // NOTE: inverted! See https://github.com/rust-windowing/winit/pull/2105/ update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::MouseWheel { device_id: DEVICE_ID, delta: LineDelta(value, 0.0), phase: TouchPhase::Moved, }, }); result = ProcResult::Value(0); } WM_KEYDOWN | WM_SYSKEYDOWN => { if msg == WM_SYSKEYDOWN { result = ProcResult::DefWindowProc(wparam); } } WM_KEYUP | WM_SYSKEYUP => { if msg == WM_SYSKEYUP && GetMenu(window) != 0 { // let Windows handle event if the window has a native menu, a modal event loop // is started here on Alt key up. result = ProcResult::DefWindowProc(wparam); } } WM_LBUTTONDOWN => { use crate::event::{ElementState::Pressed, MouseButton::Left, WindowEvent::MouseInput}; capture_mouse(window, &mut userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Pressed, button: Left, }, }); result = ProcResult::Value(0); } WM_LBUTTONUP => { use crate::event::{ ElementState::Released, MouseButton::Left, WindowEvent::MouseInput, }; release_mouse(userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Released, button: Left, }, }); result = ProcResult::Value(0); } WM_RBUTTONDOWN => { use crate::event::{ ElementState::Pressed, MouseButton::Right, WindowEvent::MouseInput, }; capture_mouse(window, &mut userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Pressed, button: Right, }, }); result = ProcResult::Value(0); } WM_RBUTTONUP => { use crate::event::{ ElementState::Released, MouseButton::Right, WindowEvent::MouseInput, }; release_mouse(userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Released, button: Right, }, }); result = ProcResult::Value(0); } WM_MBUTTONDOWN => { use crate::event::{ ElementState::Pressed, MouseButton::Middle, WindowEvent::MouseInput, }; capture_mouse(window, &mut userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Pressed, button: Middle, }, }); result = ProcResult::Value(0); } WM_MBUTTONUP => { use crate::event::{ ElementState::Released, MouseButton::Middle, WindowEvent::MouseInput, }; release_mouse(userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Released, button: Middle, }, }); result = ProcResult::Value(0); } WM_XBUTTONDOWN => { use crate::event::{ ElementState::Pressed, MouseButton::Back, MouseButton::Forward, MouseButton::Other, WindowEvent::MouseInput, }; let xbutton = super::get_xbutton_wparam(wparam as u32); capture_mouse(window, &mut userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Pressed, button: match xbutton { 1 => Back, 2 => Forward, _ => Other(xbutton), }, }, }); result = ProcResult::Value(0); } WM_XBUTTONUP => { use crate::event::{ ElementState::Released, MouseButton::Back, MouseButton::Forward, MouseButton::Other, WindowEvent::MouseInput, }; let xbutton = super::get_xbutton_wparam(wparam as u32); release_mouse(userdata.window_state_lock()); update_modifiers(window, userdata); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: MouseInput { device_id: DEVICE_ID, state: Released, button: match xbutton { 1 => Back, 2 => Forward, _ => Other(xbutton), }, }, }); result = ProcResult::Value(0); } WM_CAPTURECHANGED => { // lparam here is a handle to the window which is gaining mouse capture. // If it is the same as our window, then we're essentially retaining the capture. This // can happen if `SetCapture` is called on our window when it already has the mouse // capture. if lparam != window { userdata.window_state_lock().mouse.capture_count = 0; } result = ProcResult::Value(0); } WM_TOUCH => { let pcount = super::loword(wparam as u32) as usize; let mut inputs = Vec::with_capacity(pcount); let htouch = lparam; if GetTouchInputInfo( htouch, pcount as u32, inputs.as_mut_ptr(), mem::size_of::() as i32, ) > 0 { inputs.set_len(pcount); for input in &inputs { let mut location = POINT { x: input.x / 100, y: input.y / 100, }; if ScreenToClient(window, &mut location) == false.into() { continue; } let x = location.x as f64 + (input.x % 100) as f64 / 100f64; let y = location.y as f64 + (input.y % 100) as f64 / 100f64; let location = PhysicalPosition::new(x, y); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Touch(Touch { phase: if util::has_flag(input.dwFlags, TOUCHEVENTF_DOWN) { TouchPhase::Started } else if util::has_flag(input.dwFlags, TOUCHEVENTF_UP) { TouchPhase::Ended } else if util::has_flag(input.dwFlags, TOUCHEVENTF_MOVE) { TouchPhase::Moved } else { continue; }, location, force: None, // WM_TOUCH doesn't support pressure information id: input.dwID as u64, device_id: DEVICE_ID, }), }); } } CloseTouchInputHandle(htouch); result = ProcResult::Value(0); } WM_POINTERDOWN | WM_POINTERUPDATE | WM_POINTERUP => { if let ( Some(GetPointerFrameInfoHistory), Some(SkipPointerFrameMessages), Some(GetPointerDeviceRects), ) = ( *GET_POINTER_FRAME_INFO_HISTORY, *SKIP_POINTER_FRAME_MESSAGES, *GET_POINTER_DEVICE_RECTS, ) { let pointer_id = super::loword(wparam as u32) as u32; let mut entries_count = 0u32; let mut pointers_count = 0u32; if GetPointerFrameInfoHistory( pointer_id, &mut entries_count, &mut pointers_count, ptr::null_mut(), ) == false.into() { result = ProcResult::Value(0); return; } let pointer_info_count = (entries_count * pointers_count) as usize; let mut pointer_infos = Vec::with_capacity(pointer_info_count); if GetPointerFrameInfoHistory( pointer_id, &mut entries_count, &mut pointers_count, pointer_infos.as_mut_ptr(), ) == false.into() { result = ProcResult::Value(0); return; } pointer_infos.set_len(pointer_info_count); // https://docs.microsoft.com/en-us/windows/desktop/api/winuser/nf-winuser-getpointerframeinfohistory // The information retrieved appears in reverse chronological order, with the most recent entry in the first // row of the returned array for pointer_info in pointer_infos.iter().rev() { let mut device_rect = mem::MaybeUninit::uninit(); let mut display_rect = mem::MaybeUninit::uninit(); if GetPointerDeviceRects( pointer_info.sourceDevice, device_rect.as_mut_ptr(), display_rect.as_mut_ptr(), ) == false.into() { continue; } let device_rect = device_rect.assume_init(); let display_rect = display_rect.assume_init(); // For the most precise himetric to pixel conversion we calculate the ratio between the resolution // of the display device (pixel) and the touch device (himetric). let himetric_to_pixel_ratio_x = (display_rect.right - display_rect.left) as f64 / (device_rect.right - device_rect.left) as f64; let himetric_to_pixel_ratio_y = (display_rect.bottom - display_rect.top) as f64 / (device_rect.bottom - device_rect.top) as f64; // ptHimetricLocation's origin is 0,0 even on multi-monitor setups. // On multi-monitor setups we need to translate the himetric location to the rect of the // display device it's attached to. let x = display_rect.left as f64 + pointer_info.ptHimetricLocation.x as f64 * himetric_to_pixel_ratio_x; let y = display_rect.top as f64 + pointer_info.ptHimetricLocation.y as f64 * himetric_to_pixel_ratio_y; let mut location = POINT { x: x.floor() as i32, y: y.floor() as i32, }; if ScreenToClient(window, &mut location) == false.into() { continue; } let force = match pointer_info.pointerType { PT_TOUCH => { let mut touch_info = mem::MaybeUninit::uninit(); GET_POINTER_TOUCH_INFO.and_then(|GetPointerTouchInfo| { match GetPointerTouchInfo( pointer_info.pointerId, touch_info.as_mut_ptr(), ) { 0 => None, _ => normalize_pointer_pressure( touch_info.assume_init().pressure, ), } }) } PT_PEN => { let mut pen_info = mem::MaybeUninit::uninit(); GET_POINTER_PEN_INFO.and_then(|GetPointerPenInfo| { match GetPointerPenInfo( pointer_info.pointerId, pen_info.as_mut_ptr(), ) { 0 => None, _ => { normalize_pointer_pressure(pen_info.assume_init().pressure) } } }) } _ => None, }; let x = location.x as f64 + x.fract(); let y = location.y as f64 + y.fract(); let location = PhysicalPosition::new(x, y); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: WindowEvent::Touch(Touch { phase: if util::has_flag(pointer_info.pointerFlags, POINTER_FLAG_DOWN) { TouchPhase::Started } else if util::has_flag(pointer_info.pointerFlags, POINTER_FLAG_UP) { TouchPhase::Ended } else if util::has_flag(pointer_info.pointerFlags, POINTER_FLAG_UPDATE) { TouchPhase::Moved } else { continue; }, location, force, id: pointer_info.pointerId as u64, device_id: DEVICE_ID, }), }); } SkipPointerFrameMessages(pointer_id); } result = ProcResult::Value(0); } WM_NCACTIVATE => { let is_active = wparam != false.into(); let active_focus_changed = userdata.window_state_lock().set_active(is_active); if active_focus_changed { if is_active { gain_active_focus(window, userdata); } else { lose_active_focus(window, userdata); } } result = ProcResult::DefWindowProc(wparam); } WM_SETFOCUS => { let active_focus_changed = userdata.window_state_lock().set_focused(true); if active_focus_changed { gain_active_focus(window, userdata); } result = ProcResult::Value(0); } WM_KILLFOCUS => { let active_focus_changed = userdata.window_state_lock().set_focused(false); if active_focus_changed { lose_active_focus(window, userdata); } result = ProcResult::Value(0); } WM_SETCURSOR => { let set_cursor_to = { let window_state = userdata.window_state_lock(); // The return value for the preceding `WM_NCHITTEST` message is conveniently // provided through the low-order word of lParam. We use that here since // `WM_MOUSEMOVE` seems to come after `WM_SETCURSOR` for a given cursor movement. let in_client_area = super::loword(lparam as u32) as u32 == HTCLIENT; if in_client_area { Some(window_state.mouse.cursor) } else { None } }; match set_cursor_to { Some(cursor) => { let cursor = LoadCursorW(0, util::to_windows_cursor(cursor)); SetCursor(cursor); result = ProcResult::Value(0); } None => result = ProcResult::DefWindowProc(wparam), } } WM_GETMINMAXINFO => { let mmi = lparam as *mut MINMAXINFO; let window_state = userdata.window_state_lock(); let window_flags = window_state.window_flags; if window_state.min_size.is_some() || window_state.max_size.is_some() { if let Some(min_size) = window_state.min_size { let min_size = min_size.to_physical(window_state.scale_factor); let (width, height): (u32, u32) = window_flags.adjust_size(window, min_size).into(); (*mmi).ptMinTrackSize = POINT { x: width as i32, y: height as i32, }; } if let Some(max_size) = window_state.max_size { let max_size = max_size.to_physical(window_state.scale_factor); let (width, height): (u32, u32) = window_flags.adjust_size(window, max_size).into(); (*mmi).ptMaxTrackSize = POINT { x: width as i32, y: height as i32, }; } } result = ProcResult::Value(0); } // Only sent on Windows 8.1 or newer. On Windows 7 and older user has to log out to change // DPI, therefore all applications are closed while DPI is changing. WM_DPICHANGED => { use crate::event::WindowEvent::ScaleFactorChanged; // This message actually provides two DPI values - x and y. However MSDN says that // "you only need to use either the X-axis or the Y-axis value when scaling your // application since they are the same". // https://msdn.microsoft.com/en-us/library/windows/desktop/dn312083(v=vs.85).aspx let new_dpi_x = super::loword(wparam as u32) as u32; let new_scale_factor = dpi_to_scale_factor(new_dpi_x); let old_scale_factor: f64; let (allow_resize, window_flags) = { let mut window_state = userdata.window_state_lock(); old_scale_factor = window_state.scale_factor; window_state.scale_factor = new_scale_factor; if new_scale_factor == old_scale_factor { result = ProcResult::Value(0); return; } let allow_resize = window_state.fullscreen.is_none() && !window_state.window_flags().contains(WindowFlags::MAXIMIZED); (allow_resize, window_state.window_flags) }; // New size as suggested by Windows. let suggested_rect = *(lparam as *const RECT); // The window rect provided is the window's outer size, not it's inner size. However, // win32 doesn't provide an `UnadjustWindowRectEx` function to get the client rect from // the outer rect, so we instead adjust the window rect to get the decoration margins // and remove them from the outer size. let margin_left: i32; let margin_top: i32; // let margin_right: i32; // let margin_bottom: i32; { let adjusted_rect = window_flags .adjust_rect(window, suggested_rect) .unwrap_or(suggested_rect); margin_left = suggested_rect.left - adjusted_rect.left; margin_top = suggested_rect.top - adjusted_rect.top; // margin_right = adjusted_rect.right - suggested_rect.right; // margin_bottom = adjusted_rect.bottom - suggested_rect.bottom; } let old_physical_inner_rect = util::WindowArea::Inner .get_rect(window) .expect("failed to query (old) inner window area"); let old_physical_inner_size = PhysicalSize::new( (old_physical_inner_rect.right - old_physical_inner_rect.left) as u32, (old_physical_inner_rect.bottom - old_physical_inner_rect.top) as u32, ); // `allow_resize` prevents us from re-applying DPI adjustment to the restored size after // exiting fullscreen (the restored size is already DPI adjusted). let new_physical_inner_size = match allow_resize { // We calculate our own size because the default suggested rect doesn't do a great job // of preserving the window's logical size. true => old_physical_inner_size .to_logical::(old_scale_factor) .to_physical::(new_scale_factor), false => old_physical_inner_size, }; let new_inner_size = Arc::new(Mutex::new(new_physical_inner_size)); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: ScaleFactorChanged { scale_factor: new_scale_factor, inner_size_writer: InnerSizeWriter::new(Arc::downgrade(&new_inner_size)), }, }); let new_physical_inner_size = *new_inner_size.lock().unwrap(); drop(new_inner_size); let dragging_window: bool; { let window_state = userdata.window_state_lock(); dragging_window = window_state .window_flags() .contains(WindowFlags::MARKER_IN_SIZE_MOVE); // Unset maximized if we're changing the window's size. if new_physical_inner_size != old_physical_inner_size { WindowState::set_window_flags(window_state, window, |f| { f.set(WindowFlags::MAXIMIZED, false) }); } } let new_outer_rect: RECT; { let suggested_ul = ( suggested_rect.left + margin_left, suggested_rect.top + margin_top, ); let mut conservative_rect = RECT { left: suggested_ul.0, top: suggested_ul.1, right: suggested_ul.0 + new_physical_inner_size.width as i32, bottom: suggested_ul.1 + new_physical_inner_size.height as i32, }; conservative_rect = window_flags .adjust_rect(window, conservative_rect) .unwrap_or(conservative_rect); // If we're dragging the window, offset the window so that the cursor's // relative horizontal position in the title bar is preserved. if dragging_window { let bias = { let cursor_pos = { let mut pos = mem::zeroed(); GetCursorPos(&mut pos); pos }; let suggested_cursor_horizontal_ratio = (cursor_pos.x - suggested_rect.left) as f64 / (suggested_rect.right - suggested_rect.left) as f64; (cursor_pos.x - (suggested_cursor_horizontal_ratio * (conservative_rect.right - conservative_rect.left) as f64) as i32) - conservative_rect.left }; conservative_rect.left += bias; conservative_rect.right += bias; } // Check to see if the new window rect is on the monitor with the new DPI factor. // If it isn't, offset the window so that it is. let new_dpi_monitor = MonitorFromWindow(window, MONITOR_DEFAULTTONULL); let conservative_rect_monitor = MonitorFromRect(&conservative_rect, MONITOR_DEFAULTTONULL); new_outer_rect = if conservative_rect_monitor == new_dpi_monitor { conservative_rect } else { let get_monitor_rect = |monitor| { let mut monitor_info = MONITORINFO { cbSize: mem::size_of::() as _, ..mem::zeroed() }; GetMonitorInfoW(monitor, &mut monitor_info); monitor_info.rcMonitor }; let wrong_monitor = conservative_rect_monitor; let wrong_monitor_rect = get_monitor_rect(wrong_monitor); let new_monitor_rect = get_monitor_rect(new_dpi_monitor); // The direction to nudge the window in to get the window onto the monitor with // the new DPI factor. We calculate this by seeing which monitor edges are // shared and nudging away from the wrong monitor based on those. #[allow(clippy::bool_to_int_with_if)] let delta_nudge_to_dpi_monitor = ( if wrong_monitor_rect.left == new_monitor_rect.right { -1 } else if wrong_monitor_rect.right == new_monitor_rect.left { 1 } else { 0 }, if wrong_monitor_rect.bottom == new_monitor_rect.top { 1 } else if wrong_monitor_rect.top == new_monitor_rect.bottom { -1 } else { 0 }, ); let abort_after_iterations = new_monitor_rect.right - new_monitor_rect.left + new_monitor_rect.bottom - new_monitor_rect.top; for _ in 0..abort_after_iterations { conservative_rect.left += delta_nudge_to_dpi_monitor.0; conservative_rect.right += delta_nudge_to_dpi_monitor.0; conservative_rect.top += delta_nudge_to_dpi_monitor.1; conservative_rect.bottom += delta_nudge_to_dpi_monitor.1; if MonitorFromRect(&conservative_rect, MONITOR_DEFAULTTONULL) == new_dpi_monitor { break; } } conservative_rect }; } SetWindowPos( window, 0, new_outer_rect.left, new_outer_rect.top, new_outer_rect.right - new_outer_rect.left, new_outer_rect.bottom - new_outer_rect.top, SWP_NOZORDER | SWP_NOACTIVATE, ); result = ProcResult::Value(0); } WM_SETTINGCHANGE => { use crate::event::WindowEvent::ThemeChanged; let preferred_theme = userdata.window_state_lock().preferred_theme; if preferred_theme.is_none() { let new_theme = try_theme(window, preferred_theme); let mut window_state = userdata.window_state_lock(); if window_state.current_theme != new_theme { window_state.current_theme = new_theme; drop(window_state); userdata.send_event(Event::WindowEvent { window_id: RootWindowId(WindowId(window)), event: ThemeChanged(new_theme), }); } } result = ProcResult::DefWindowProc(wparam); } _ => { if msg == DESTROY_MSG_ID.get() { DestroyWindow(window); result = ProcResult::Value(0); } else if msg == SET_RETAIN_STATE_ON_SIZE_MSG_ID.get() { let mut window_state = userdata.window_state_lock(); window_state.set_window_flags_in_place(|f| { f.set(WindowFlags::MARKER_RETAIN_STATE_ON_SIZE, wparam != 0) }); result = ProcResult::Value(0); } else if msg == TASKBAR_CREATED.get() { let window_state = userdata.window_state_lock(); set_skip_taskbar(window, window_state.skip_taskbar); result = ProcResult::DefWindowProc(wparam); } else { result = ProcResult::DefWindowProc(wparam); } } }; userdata .event_loop_runner .catch_unwind(callback) .unwrap_or_else(|| result = ProcResult::Value(-1)); match result { ProcResult::DefWindowProc(wparam) => DefWindowProcW(window, msg, wparam, lparam), ProcResult::Value(val) => val, } } unsafe extern "system" fn thread_event_target_callback( window: HWND, msg: u32, wparam: WPARAM, lparam: LPARAM, ) -> LRESULT { let userdata_ptr = super::get_window_long(window, GWL_USERDATA) as *mut ThreadMsgTargetData; if userdata_ptr.is_null() { // `userdata_ptr` will always be null for the first `WM_GETMINMAXINFO`, as well as `WM_NCCREATE` and // `WM_CREATE`. return DefWindowProcW(window, msg, wparam, lparam); } let userdata = Box::from_raw(userdata_ptr); if msg != WM_PAINT { RedrawWindow(window, ptr::null(), 0, RDW_INTERNALPAINT); } let mut userdata_removed = false; // I decided to bind the closure to `callback` and pass it to catch_unwind rather than passing // the closure to catch_unwind directly so that the match body indendation wouldn't change and // the git blame and history would be preserved. let callback = || match msg { WM_NCDESTROY => { super::set_window_long(window, GWL_USERDATA, 0); userdata_removed = true; 0 } WM_PAINT => { ValidateRect(window, ptr::null()); // Default WM_PAINT behaviour. This makes sure modals and popups are shown immediatly when opening them. DefWindowProcW(window, msg, wparam, lparam) } WM_INPUT_DEVICE_CHANGE => { let event = match wparam as u32 { GIDC_ARRIVAL => DeviceEvent::Added, GIDC_REMOVAL => DeviceEvent::Removed, _ => unreachable!(), }; userdata.send_event(Event::DeviceEvent { device_id: wrap_device_id(lparam as u32), event, }); 0 } WM_INPUT => { if let Some(data) = raw_input::get_raw_input_data(lparam as _) { handle_raw_input(&userdata, data); } DefWindowProcW(window, msg, wparam, lparam) } _ if msg == USER_EVENT_MSG_ID.get() => { if let Ok(event) = userdata.user_event_receiver.recv() { userdata.send_event(Event::UserEvent(event)); } 0 } _ if msg == EXEC_MSG_ID.get() => { let mut function: ThreadExecFn = Box::from_raw(wparam as *mut _); function(); 0 } _ => DefWindowProcW(window, msg, wparam, lparam), }; let result = userdata .event_loop_runner .catch_unwind(callback) .unwrap_or(-1); if userdata_removed { drop(userdata); } else { Box::into_raw(userdata); } result } unsafe fn handle_raw_input(userdata: &ThreadMsgTargetData, data: RAWINPUT) { use crate::event::{ DeviceEvent::{Button, Key, Motion, MouseMotion, MouseWheel}, ElementState::{Pressed, Released}, MouseScrollDelta::LineDelta, }; let device_id = wrap_device_id(data.header.hDevice as _); if data.header.dwType == RIM_TYPEMOUSE { let mouse = data.data.mouse; if util::has_flag(mouse.usFlags as u32, MOUSE_MOVE_RELATIVE) { let x = mouse.lLastX as f64; let y = mouse.lLastY as f64; if x != 0.0 { userdata.send_event(Event::DeviceEvent { device_id, event: Motion { axis: 0, value: x }, }); } if y != 0.0 { userdata.send_event(Event::DeviceEvent { device_id, event: Motion { axis: 1, value: y }, }); } if x != 0.0 || y != 0.0 { userdata.send_event(Event::DeviceEvent { device_id, event: MouseMotion { delta: (x, y) }, }); } } let button_flags = mouse.Anonymous.Anonymous.usButtonFlags; if util::has_flag(button_flags as u32, RI_MOUSE_WHEEL) { let button_data = mouse.Anonymous.Anonymous.usButtonData; // We must cast to i16 first, becaues `usButtonData` must be interpreted as signed. let delta = button_data as i16 as f32 / WHEEL_DELTA as f32; userdata.send_event(Event::DeviceEvent { device_id, event: MouseWheel { delta: LineDelta(0.0, delta), }, }); } let button_state = raw_input::get_raw_mouse_button_state(button_flags as u32); // Left, middle, and right, respectively. for (index, state) in button_state.iter().enumerate() { if let Some(state) = *state { // This gives us consistency with X11, since there doesn't // seem to be anything else reasonable to do for a mouse // button ID. let button = (index + 1) as _; userdata.send_event(Event::DeviceEvent { device_id, event: Button { button, state }, }); } } } else if data.header.dwType == RIM_TYPEKEYBOARD { let keyboard = data.data.keyboard; let pressed = keyboard.Message == WM_KEYDOWN || keyboard.Message == WM_SYSKEYDOWN; let released = keyboard.Message == WM_KEYUP || keyboard.Message == WM_SYSKEYUP; if !pressed && !released { return; } let state = if pressed { Pressed } else { Released }; let extension = { if util::has_flag(keyboard.Flags, RI_KEY_E0 as _) { 0xE000 } else if util::has_flag(keyboard.Flags, RI_KEY_E1 as _) { 0xE100 } else { 0x0000 } }; let scancode = if keyboard.MakeCode == 0 { // In some cases (often with media keys) the device reports a scancode of 0 but a // valid virtual key. In these cases we obtain the scancode from the virtual key. MapVirtualKeyW(keyboard.VKey as u32, MAPVK_VK_TO_VSC_EX) as u16 } else { keyboard.MakeCode | extension }; if scancode == 0xE11D || scancode == 0xE02A { // At the hardware (or driver?) level, pressing the Pause key is equivalent to pressing // Ctrl+NumLock. // This equvalence means that if the user presses Pause, the keyboard will emit two // subsequent keypresses: // 1, 0xE11D - Which is a left Ctrl (0x1D) with an extension flag (0xE100) // 2, 0x0045 - Which on its own can be interpreted as Pause // // There's another combination which isn't quite an equivalence: // PrtSc used to be Shift+Asterisk. This means that on some keyboards, presssing // PrtSc (print screen) produces the following sequence: // 1, 0xE02A - Which is a left shift (0x2A) with an extension flag (0xE000) // 2, 0xE037 - Which is a numpad multiply (0x37) with an exteion flag (0xE000). This on // its own it can be interpreted as PrtSc // // For this reason, if we encounter the first keypress, we simply ignore it, trusting // that there's going to be another event coming, from which we can extract the // appropriate key. // For more on this, read the article by Raymond Chen, titled: // "Why does Ctrl+ScrollLock cancel dialogs?" // https://devblogs.microsoft.com/oldnewthing/20080211-00/?p=23503 return; } let code = if keyboard.VKey == VK_NUMLOCK { // Historically, the NumLock and the Pause key were one and the same physical key. // The user could trigger Pause by pressing Ctrl+NumLock. // Now these are often physically separate and the two keys can be differentiated by // checking the extension flag of the scancode. NumLock is 0xE045, Pause is 0x0045. // // However in this event, both keys are reported as 0x0045 even on modern hardware. // Therefore we use the virtual key instead to determine whether it's a NumLock and // set the KeyCode accordingly. // // For more on this, read the article by Raymond Chen, titled: // "Why does Ctrl+ScrollLock cancel dialogs?" // https://devblogs.microsoft.com/oldnewthing/20080211-00/?p=23503 KeyCode::NumLock } else { KeyCode::from_scancode(scancode as u32) }; if keyboard.VKey == VK_SHIFT { match code { KeyCode::NumpadDecimal | KeyCode::Numpad0 | KeyCode::Numpad1 | KeyCode::Numpad2 | KeyCode::Numpad3 | KeyCode::Numpad4 | KeyCode::Numpad5 | KeyCode::Numpad6 | KeyCode::Numpad7 | KeyCode::Numpad8 | KeyCode::Numpad9 => { // On Windows, holding the Shift key makes numpad keys behave as if NumLock // wasn't active. The way this is exposed to applications by the system is that // the application receives a fake key release event for the shift key at the // moment when the numpad key is pressed, just before receiving the numpad key // as well. // // The issue is that in the raw device event (here), the fake shift release // event reports the numpad key as the scancode. Unfortunately, the event doesn't // have any information to tell whether it's the left shift or the right shift // that needs to get the fake release (or press) event so we don't forward this // event to the application at all. // // For more on this, read the article by Raymond Chen, titled: // "The shift key overrides NumLock" // https://devblogs.microsoft.com/oldnewthing/20040906-00/?p=37953 return; } _ => (), } } userdata.send_event(Event::DeviceEvent { device_id, event: Key(RawKeyEvent { physical_key: code, state, }), }); } }