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