window.rs

  1use crate::{
  2    executor,
  3    geometry::vector::Vector2F,
  4    keymap::Keystroke,
  5    platform::{self, Event, WindowContext},
  6    Scene,
  7};
  8use cocoa::{
  9    appkit::{
 10        NSApplication, NSBackingStoreBuffered, NSScreen, NSView, NSViewHeightSizable,
 11        NSViewWidthSizable, NSWindow, NSWindowStyleMask,
 12    },
 13    base::{id, nil},
 14    foundation::{NSAutoreleasePool, NSInteger, NSSize, NSString},
 15    quartzcore::AutoresizingMask,
 16};
 17use ctor::ctor;
 18use foreign_types::ForeignType as _;
 19use objc::{
 20    class,
 21    declare::ClassDecl,
 22    msg_send,
 23    runtime::{Class, Object, Protocol, Sel, BOOL, NO, YES},
 24    sel, sel_impl,
 25};
 26use pathfinder_geometry::vector::vec2f;
 27use smol::Timer;
 28use std::{
 29    cell::RefCell,
 30    ffi::c_void,
 31    mem, ptr,
 32    rc::{Rc, Weak},
 33    sync::Arc,
 34    time::Duration,
 35};
 36
 37use super::{geometry::RectFExt, renderer::Renderer};
 38
 39const WINDOW_STATE_IVAR: &'static str = "windowState";
 40
 41static mut WINDOW_CLASS: *const Class = ptr::null();
 42static mut VIEW_CLASS: *const Class = ptr::null();
 43
 44#[allow(non_upper_case_globals)]
 45const NSViewLayerContentsRedrawDuringViewResize: NSInteger = 2;
 46
 47#[ctor]
 48unsafe fn build_classes() {
 49    WINDOW_CLASS = {
 50        let mut decl = ClassDecl::new("GPUIWindow", class!(NSWindow)).unwrap();
 51        decl.add_ivar::<*mut c_void>(WINDOW_STATE_IVAR);
 52        decl.add_method(sel!(dealloc), dealloc_window as extern "C" fn(&Object, Sel));
 53        decl.add_method(
 54            sel!(canBecomeMainWindow),
 55            yes as extern "C" fn(&Object, Sel) -> BOOL,
 56        );
 57        decl.add_method(
 58            sel!(canBecomeKeyWindow),
 59            yes as extern "C" fn(&Object, Sel) -> BOOL,
 60        );
 61        decl.add_method(
 62            sel!(sendEvent:),
 63            send_event as extern "C" fn(&Object, Sel, id),
 64        );
 65        decl.add_method(sel!(close), close_window as extern "C" fn(&Object, Sel));
 66        decl.register()
 67    };
 68
 69    VIEW_CLASS = {
 70        let mut decl = ClassDecl::new("GPUIView", class!(NSView)).unwrap();
 71        decl.add_ivar::<*mut c_void>(WINDOW_STATE_IVAR);
 72
 73        decl.add_method(sel!(dealloc), dealloc_view as extern "C" fn(&Object, Sel));
 74
 75        decl.add_method(
 76            sel!(keyDown:),
 77            handle_view_event as extern "C" fn(&Object, Sel, id),
 78        );
 79        decl.add_method(
 80            sel!(mouseDown:),
 81            handle_view_event as extern "C" fn(&Object, Sel, id),
 82        );
 83        decl.add_method(
 84            sel!(mouseUp:),
 85            handle_view_event as extern "C" fn(&Object, Sel, id),
 86        );
 87        decl.add_method(
 88            sel!(mouseMoved:),
 89            handle_view_event as extern "C" fn(&Object, Sel, id),
 90        );
 91        decl.add_method(
 92            sel!(mouseDragged:),
 93            handle_view_event as extern "C" fn(&Object, Sel, id),
 94        );
 95        decl.add_method(
 96            sel!(scrollWheel:),
 97            handle_view_event as extern "C" fn(&Object, Sel, id),
 98        );
 99
100        decl.add_method(
101            sel!(makeBackingLayer),
102            make_backing_layer as extern "C" fn(&Object, Sel) -> id,
103        );
104
105        decl.add_protocol(Protocol::get("CALayerDelegate").unwrap());
106        decl.add_method(
107            sel!(viewDidChangeBackingProperties),
108            view_did_change_backing_properties as extern "C" fn(&Object, Sel),
109        );
110        decl.add_method(
111            sel!(setFrameSize:),
112            set_frame_size as extern "C" fn(&Object, Sel, NSSize),
113        );
114        decl.add_method(
115            sel!(displayLayer:),
116            display_layer as extern "C" fn(&Object, Sel, id),
117        );
118
119        decl.register()
120    };
121}
122
123pub struct Window(Rc<RefCell<WindowState>>);
124
125struct WindowState {
126    id: usize,
127    native_window: id,
128    event_callback: Option<Box<dyn FnMut(Event)>>,
129    resize_callback: Option<Box<dyn FnMut(&mut dyn platform::WindowContext)>>,
130    close_callback: Option<Box<dyn FnOnce()>>,
131    synthetic_drag_counter: usize,
132    executor: Rc<executor::Foreground>,
133    scene_to_render: Option<Scene>,
134    renderer: Renderer,
135    command_queue: metal::CommandQueue,
136    last_fresh_keydown: Option<(Keystroke, String)>,
137    layer: id,
138}
139
140impl Window {
141    pub fn open(
142        id: usize,
143        options: platform::WindowOptions,
144        executor: Rc<executor::Foreground>,
145        fonts: Arc<dyn platform::FontSystem>,
146    ) -> Self {
147        const PIXEL_FORMAT: metal::MTLPixelFormat = metal::MTLPixelFormat::BGRA8Unorm;
148
149        unsafe {
150            let pool = NSAutoreleasePool::new(nil);
151
152            let frame = options.bounds.to_ns_rect();
153            let style_mask = NSWindowStyleMask::NSClosableWindowMask
154                | NSWindowStyleMask::NSMiniaturizableWindowMask
155                | NSWindowStyleMask::NSResizableWindowMask
156                | NSWindowStyleMask::NSTitledWindowMask;
157
158            let native_window: id = msg_send![WINDOW_CLASS, alloc];
159            let native_window = native_window.initWithContentRect_styleMask_backing_defer_(
160                frame,
161                style_mask,
162                NSBackingStoreBuffered,
163                NO,
164            );
165            assert!(!native_window.is_null());
166
167            let device =
168                metal::Device::system_default().expect("could not find default metal device");
169
170            let layer: id = msg_send![class!(CAMetalLayer), layer];
171            let _: () = msg_send![layer, setDevice: device.as_ptr()];
172            let _: () = msg_send![layer, setPixelFormat: PIXEL_FORMAT];
173            let _: () = msg_send![layer, setAllowsNextDrawableTimeout: NO];
174            let _: () = msg_send![layer, setNeedsDisplayOnBoundsChange: YES];
175            let _: () = msg_send![layer, setPresentsWithTransaction: YES];
176            let _: () = msg_send![
177                layer,
178                setAutoresizingMask: AutoresizingMask::WIDTH_SIZABLE
179                    | AutoresizingMask::HEIGHT_SIZABLE
180            ];
181
182            let native_view: id = msg_send![VIEW_CLASS, alloc];
183            let native_view = NSView::init(native_view);
184            assert!(!native_view.is_null());
185
186            let window = Self(Rc::new(RefCell::new(WindowState {
187                id,
188                native_window,
189                event_callback: None,
190                resize_callback: None,
191                close_callback: None,
192                synthetic_drag_counter: 0,
193                executor,
194                scene_to_render: Default::default(),
195                renderer: Renderer::new(device.clone(), PIXEL_FORMAT, fonts),
196                command_queue: device.new_command_queue(),
197                last_fresh_keydown: None,
198                layer,
199            })));
200
201            (*native_window).set_ivar(
202                WINDOW_STATE_IVAR,
203                Rc::into_raw(window.0.clone()) as *const c_void,
204            );
205            (*native_view).set_ivar(
206                WINDOW_STATE_IVAR,
207                Rc::into_raw(window.0.clone()) as *const c_void,
208            );
209
210            if let Some(title) = options.title.as_ref() {
211                native_window.setTitle_(NSString::alloc(nil).init_str(title));
212            }
213            native_window.setAcceptsMouseMovedEvents_(YES);
214
215            native_view.setAutoresizingMask_(NSViewWidthSizable | NSViewHeightSizable);
216            native_view.setWantsBestResolutionOpenGLSurface_(YES);
217
218            // From winit crate: On Mojave, views automatically become layer-backed shortly after
219            // being added to a native_window. Changing the layer-backedness of a view breaks the
220            // association between the view and its associated OpenGL context. To work around this,
221            // on we explicitly make the view layer-backed up front so that AppKit doesn't do it
222            // itself and break the association with its context.
223            native_view.setWantsLayer(YES);
224            let _: () = msg_send![
225                native_view,
226                setLayerContentsRedrawPolicy: NSViewLayerContentsRedrawDuringViewResize
227            ];
228
229            native_window.setContentView_(native_view.autorelease());
230            native_window.makeFirstResponder_(native_view);
231
232            native_window.center();
233            native_window.makeKeyAndOrderFront_(nil);
234
235            pool.drain();
236
237            window
238        }
239    }
240
241    pub fn key_window_id() -> Option<usize> {
242        unsafe {
243            let app = NSApplication::sharedApplication(nil);
244            let key_window: id = msg_send![app, keyWindow];
245            if key_window.is_null() {
246                None
247            } else {
248                let id = get_window_state(&*key_window).borrow().id;
249                Some(id)
250            }
251        }
252    }
253}
254
255impl Drop for Window {
256    fn drop(&mut self) {
257        unsafe {
258            self.0.as_ref().borrow().native_window.close();
259        }
260    }
261}
262
263impl platform::Window for Window {
264    fn on_event(&mut self, callback: Box<dyn FnMut(Event)>) {
265        self.0.as_ref().borrow_mut().event_callback = Some(callback);
266    }
267
268    fn on_resize(&mut self, callback: Box<dyn FnMut(&mut dyn platform::WindowContext)>) {
269        self.0.as_ref().borrow_mut().resize_callback = Some(callback);
270    }
271
272    fn on_close(&mut self, callback: Box<dyn FnOnce()>) {
273        self.0.as_ref().borrow_mut().close_callback = Some(callback);
274    }
275}
276
277impl platform::WindowContext for Window {
278    fn size(&self) -> Vector2F {
279        self.0.as_ref().borrow().size()
280    }
281
282    fn scale_factor(&self) -> f32 {
283        self.0.as_ref().borrow().scale_factor()
284    }
285
286    fn present_scene(&mut self, scene: Scene) {
287        self.0.as_ref().borrow_mut().present_scene(scene);
288    }
289}
290
291impl platform::WindowContext for WindowState {
292    fn size(&self) -> Vector2F {
293        let NSSize { width, height, .. } =
294            unsafe { NSView::frame(self.native_window.contentView()) }.size;
295        vec2f(width as f32, height as f32)
296    }
297
298    fn scale_factor(&self) -> f32 {
299        unsafe {
300            let screen: id = msg_send![self.native_window, screen];
301            NSScreen::backingScaleFactor(screen) as f32
302        }
303    }
304
305    fn present_scene(&mut self, scene: Scene) {
306        self.scene_to_render = Some(scene);
307        unsafe {
308            let _: () = msg_send![self.native_window.contentView(), setNeedsDisplay: YES];
309        }
310    }
311}
312
313unsafe fn get_window_state(object: &Object) -> Rc<RefCell<WindowState>> {
314    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
315    let rc1 = Rc::from_raw(raw as *mut RefCell<WindowState>);
316    let rc2 = rc1.clone();
317    mem::forget(rc1);
318    rc2
319}
320
321unsafe fn drop_window_state(object: &Object) {
322    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
323    Rc::from_raw(raw as *mut RefCell<WindowState>);
324}
325
326extern "C" fn yes(_: &Object, _: Sel) -> BOOL {
327    YES
328}
329
330extern "C" fn dealloc_window(this: &Object, _: Sel) {
331    unsafe {
332        drop_window_state(this);
333        let () = msg_send![super(this, class!(NSWindow)), dealloc];
334    }
335}
336
337extern "C" fn dealloc_view(this: &Object, _: Sel) {
338    unsafe {
339        drop_window_state(this);
340        let () = msg_send![super(this, class!(NSView)), dealloc];
341    }
342}
343
344extern "C" fn handle_view_event(this: &Object, _: Sel, native_event: id) {
345    let window_state = unsafe { get_window_state(this) };
346    let weak_window_state = Rc::downgrade(&window_state);
347    let mut window_state_borrow = window_state.as_ref().borrow_mut();
348
349    let event = unsafe { Event::from_native(native_event, Some(window_state_borrow.size().y())) };
350
351    if let Some(event) = event {
352        match &event {
353            Event::LeftMouseDragged { position } => {
354                window_state_borrow.synthetic_drag_counter += 1;
355                window_state_borrow
356                    .executor
357                    .spawn(synthetic_drag(
358                        weak_window_state,
359                        window_state_borrow.synthetic_drag_counter,
360                        *position,
361                    ))
362                    .detach();
363            }
364            Event::LeftMouseUp { .. } => {
365                window_state_borrow.synthetic_drag_counter += 1;
366            }
367
368            // Ignore events from held-down keys after some of the initially-pressed keys
369            // were released.
370            Event::KeyDown {
371                chars,
372                keystroke,
373                is_held,
374            } => {
375                let keydown = (keystroke.clone(), chars.clone());
376                if *is_held {
377                    if window_state_borrow.last_fresh_keydown.as_ref() != Some(&keydown) {
378                        return;
379                    }
380                } else {
381                    window_state_borrow.last_fresh_keydown = Some(keydown);
382                }
383            }
384
385            _ => {}
386        }
387
388        if let Some(mut callback) = window_state_borrow.event_callback.take() {
389            drop(window_state_borrow);
390            callback(event);
391            window_state.borrow_mut().event_callback = Some(callback);
392        }
393    }
394}
395
396extern "C" fn send_event(this: &Object, _: Sel, native_event: id) {
397    unsafe {
398        let () = msg_send![super(this, class!(NSWindow)), sendEvent: native_event];
399    }
400}
401
402extern "C" fn close_window(this: &Object, _: Sel) {
403    unsafe {
404        let close_callback = {
405            let window_state = get_window_state(this);
406            window_state
407                .as_ref()
408                .try_borrow_mut()
409                .ok()
410                .and_then(|mut window_state| window_state.close_callback.take())
411        };
412
413        if let Some(callback) = close_callback {
414            callback();
415        }
416
417        let () = msg_send![super(this, class!(NSWindow)), close];
418    }
419}
420
421extern "C" fn make_backing_layer(this: &Object, _: Sel) -> id {
422    let window_state = unsafe { get_window_state(this) };
423    let window_state = window_state.as_ref().borrow();
424    window_state.layer
425}
426
427extern "C" fn view_did_change_backing_properties(this: &Object, _: Sel) {
428    let window_state = unsafe { get_window_state(this) };
429    let mut window_state = window_state.as_ref().borrow_mut();
430
431    unsafe {
432        let _: () =
433            msg_send![window_state.layer, setContentsScale: window_state.scale_factor() as f64];
434    }
435
436    if let Some(mut callback) = window_state.resize_callback.take() {
437        callback(&mut *window_state);
438        window_state.resize_callback = Some(callback);
439    };
440}
441
442extern "C" fn set_frame_size(this: &Object, _: Sel, size: NSSize) {
443    let window_state = unsafe { get_window_state(this) };
444    let mut window_state = window_state.as_ref().borrow_mut();
445
446    if window_state.size() == vec2f(size.width as f32, size.height as f32) {
447        return;
448    }
449
450    unsafe {
451        let _: () = msg_send![super(this, class!(NSView)), setFrameSize: size];
452    }
453
454    let scale_factor = window_state.scale_factor() as f64;
455    let drawable_size: NSSize = NSSize {
456        width: size.width * scale_factor,
457        height: size.height * scale_factor,
458    };
459
460    unsafe {
461        let _: () = msg_send![window_state.layer, setDrawableSize: drawable_size];
462    }
463
464    if let Some(mut callback) = window_state.resize_callback.take() {
465        callback(&mut *window_state);
466        window_state.resize_callback = Some(callback);
467    };
468}
469
470extern "C" fn display_layer(this: &Object, _: Sel, _: id) {
471    unsafe {
472        let window_state = get_window_state(this);
473        let mut window_state = window_state.as_ref().borrow_mut();
474
475        if let Some(scene) = window_state.scene_to_render.take() {
476            let drawable: &metal::MetalDrawableRef = msg_send![window_state.layer, nextDrawable];
477            let command_queue = window_state.command_queue.clone();
478            let command_buffer = command_queue.new_command_buffer();
479
480            let size = window_state.size();
481            let scale_factor = window_state.scale_factor();
482
483            window_state.renderer.render(
484                &scene,
485                size * scale_factor,
486                command_buffer,
487                drawable.texture(),
488            );
489
490            command_buffer.commit();
491            command_buffer.wait_until_completed();
492            drawable.present();
493        };
494    }
495}
496
497async fn synthetic_drag(
498    window_state: Weak<RefCell<WindowState>>,
499    drag_id: usize,
500    position: Vector2F,
501) {
502    loop {
503        Timer::after(Duration::from_millis(16)).await;
504        if let Some(window_state) = window_state.upgrade() {
505            let mut window_state_borrow = window_state.borrow_mut();
506            if window_state_borrow.synthetic_drag_counter == drag_id {
507                if let Some(mut callback) = window_state_borrow.event_callback.take() {
508                    drop(window_state_borrow);
509                    callback(Event::LeftMouseDragged { position });
510                    window_state.borrow_mut().event_callback = Some(callback);
511                }
512            } else {
513                break;
514            }
515        }
516    }
517}