window.rs

  1use crate::{
  2    executor,
  3    geometry::vector::Vector2F,
  4    platform::{self, Event, WindowContext},
  5    Scene,
  6};
  7use anyhow::{anyhow, Result};
  8use cocoa::{
  9    appkit::{
 10        NSBackingStoreBuffered, NSScreen, NSView, NSViewHeightSizable, NSViewWidthSizable,
 11        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!(mouseDragged:),
 88            handle_view_event as extern "C" fn(&Object, Sel, id),
 89        );
 90        decl.add_method(
 91            sel!(scrollWheel:),
 92            handle_view_event as extern "C" fn(&Object, Sel, id),
 93        );
 94
 95        decl.add_method(
 96            sel!(makeBackingLayer),
 97            make_backing_layer as extern "C" fn(&Object, Sel) -> id,
 98        );
 99
100        decl.add_protocol(Protocol::get("CALayerDelegate").unwrap());
101        decl.add_method(
102            sel!(viewDidChangeBackingProperties),
103            view_did_change_backing_properties as extern "C" fn(&Object, Sel),
104        );
105        decl.add_method(
106            sel!(setFrameSize:),
107            set_frame_size as extern "C" fn(&Object, Sel, NSSize),
108        );
109        decl.add_method(
110            sel!(displayLayer:),
111            display_layer as extern "C" fn(&Object, Sel, id),
112        );
113
114        decl.register()
115    };
116}
117
118pub struct Window(Rc<RefCell<WindowState>>);
119
120struct WindowState {
121    native_window: id,
122    event_callback: Option<Box<dyn FnMut(Event)>>,
123    resize_callback: Option<Box<dyn FnMut(&mut dyn platform::WindowContext)>>,
124    synthetic_drag_counter: usize,
125    executor: Rc<executor::Foreground>,
126    scene_to_render: Option<Scene>,
127    renderer: Renderer,
128    command_queue: metal::CommandQueue,
129    layer: id,
130}
131
132impl Window {
133    pub fn open(
134        options: platform::WindowOptions,
135        executor: Rc<executor::Foreground>,
136        fonts: Arc<dyn platform::FontSystem>,
137    ) -> Result<Self> {
138        const PIXEL_FORMAT: metal::MTLPixelFormat = metal::MTLPixelFormat::BGRA8Unorm;
139
140        unsafe {
141            let pool = NSAutoreleasePool::new(nil);
142
143            let frame = options.bounds.to_ns_rect();
144            let style_mask = NSWindowStyleMask::NSClosableWindowMask
145                | NSWindowStyleMask::NSMiniaturizableWindowMask
146                | NSWindowStyleMask::NSResizableWindowMask
147                | NSWindowStyleMask::NSTitledWindowMask;
148
149            let native_window: id = msg_send![WINDOW_CLASS, alloc];
150            let native_window = native_window.initWithContentRect_styleMask_backing_defer_(
151                frame,
152                style_mask,
153                NSBackingStoreBuffered,
154                NO,
155            );
156
157            if native_window == nil {
158                return Err(anyhow!("window returned nil from initializer"));
159            }
160
161            let device = metal::Device::system_default()
162                .ok_or_else(|| anyhow!("could not find default metal device"))?;
163
164            let layer: id = msg_send![class!(CAMetalLayer), layer];
165            let _: () = msg_send![layer, setDevice: device.as_ptr()];
166            let _: () = msg_send![layer, setPixelFormat: PIXEL_FORMAT];
167            let _: () = msg_send![layer, setAllowsNextDrawableTimeout: NO];
168            let _: () = msg_send![layer, setNeedsDisplayOnBoundsChange: YES];
169            let _: () = msg_send![layer, setPresentsWithTransaction: YES];
170            let _: () = msg_send![
171                layer,
172                setAutoresizingMask: AutoresizingMask::WIDTH_SIZABLE
173                    | AutoresizingMask::HEIGHT_SIZABLE
174            ];
175
176            let native_view: id = msg_send![VIEW_CLASS, alloc];
177            let native_view = NSView::init(native_view);
178            if native_view == nil {
179                return Err(anyhow!("view return nil from initializer"));
180            }
181
182            let window = Self(Rc::new(RefCell::new(WindowState {
183                native_window,
184                event_callback: None,
185                resize_callback: None,
186                synthetic_drag_counter: 0,
187                executor,
188                scene_to_render: Default::default(),
189                renderer: Renderer::new(device.clone(), PIXEL_FORMAT, fonts)?,
190                command_queue: device.new_command_queue(),
191                layer,
192            })));
193
194            (*native_window).set_ivar(
195                WINDOW_STATE_IVAR,
196                Rc::into_raw(window.0.clone()) as *const c_void,
197            );
198            (*native_view).set_ivar(
199                WINDOW_STATE_IVAR,
200                Rc::into_raw(window.0.clone()) as *const c_void,
201            );
202
203            if let Some(title) = options.title.as_ref() {
204                native_window.setTitle_(NSString::alloc(nil).init_str(title));
205            }
206            native_window.setAcceptsMouseMovedEvents_(YES);
207
208            native_view.setAutoresizingMask_(NSViewWidthSizable | NSViewHeightSizable);
209            native_view.setWantsBestResolutionOpenGLSurface_(YES);
210
211            // From winit crate: On Mojave, views automatically become layer-backed shortly after
212            // being added to a native_window. Changing the layer-backedness of a view breaks the
213            // association between the view and its associated OpenGL context. To work around this,
214            // on we explicitly make the view layer-backed up front so that AppKit doesn't do it
215            // itself and break the association with its context.
216            native_view.setWantsLayer(YES);
217            let _: () = msg_send![
218                native_view,
219                setLayerContentsRedrawPolicy: NSViewLayerContentsRedrawDuringViewResize
220            ];
221
222            native_window.setContentView_(native_view.autorelease());
223            native_window.makeFirstResponder_(native_view);
224
225            native_window.center();
226            native_window.makeKeyAndOrderFront_(nil);
227
228            pool.drain();
229
230            Ok(window)
231        }
232    }
233}
234
235impl Drop for Window {
236    fn drop(&mut self) {
237        unsafe {
238            self.0.as_ref().borrow().native_window.close();
239        }
240    }
241}
242
243impl platform::Window for Window {
244    fn on_event(&mut self, callback: Box<dyn FnMut(Event)>) {
245        self.0.as_ref().borrow_mut().event_callback = Some(callback);
246    }
247
248    fn on_resize(&mut self, callback: Box<dyn FnMut(&mut dyn platform::WindowContext)>) {
249        self.0.as_ref().borrow_mut().resize_callback = Some(callback);
250    }
251}
252
253impl platform::WindowContext for Window {
254    fn size(&self) -> Vector2F {
255        self.0.as_ref().borrow().size()
256    }
257
258    fn scale_factor(&self) -> f32 {
259        self.0.as_ref().borrow().scale_factor()
260    }
261
262    fn present_scene(&mut self, scene: Scene) {
263        self.0.as_ref().borrow_mut().present_scene(scene);
264    }
265}
266
267impl platform::WindowContext for WindowState {
268    fn size(&self) -> Vector2F {
269        let NSSize { width, height, .. } =
270            unsafe { NSView::frame(self.native_window.contentView()) }.size;
271        vec2f(width as f32, height as f32)
272    }
273
274    fn scale_factor(&self) -> f32 {
275        unsafe {
276            let screen: id = msg_send![self.native_window, screen];
277            NSScreen::backingScaleFactor(screen) as f32
278        }
279    }
280
281    fn present_scene(&mut self, scene: Scene) {
282        self.scene_to_render = Some(scene);
283        unsafe {
284            let _: () = msg_send![self.native_window.contentView(), setNeedsDisplay: YES];
285        }
286    }
287}
288
289unsafe fn get_window_state(object: &Object) -> Rc<RefCell<WindowState>> {
290    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
291    let rc1 = Rc::from_raw(raw as *mut RefCell<WindowState>);
292    let rc2 = rc1.clone();
293    mem::forget(rc1);
294    rc2
295}
296
297unsafe fn drop_window_state(object: &Object) {
298    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
299    Rc::from_raw(raw as *mut WindowState);
300}
301
302extern "C" fn yes(_: &Object, _: Sel) -> BOOL {
303    YES
304}
305
306extern "C" fn dealloc_window(this: &Object, _: Sel) {
307    unsafe {
308        drop_window_state(this);
309        let () = msg_send![super(this, class!(NSWindow)), dealloc];
310    }
311}
312
313extern "C" fn dealloc_view(this: &Object, _: Sel) {
314    unsafe {
315        drop_window_state(this);
316        let () = msg_send![super(this, class!(NSView)), dealloc];
317    }
318}
319
320extern "C" fn handle_view_event(this: &Object, _: Sel, native_event: id) {
321    let window_state = unsafe { get_window_state(this) };
322    let weak_window_state = Rc::downgrade(&window_state);
323    let mut window_state_borrow = window_state.as_ref().borrow_mut();
324
325    let event = unsafe { Event::from_native(native_event, Some(window_state_borrow.size().y())) };
326
327    if let Some(event) = event {
328        match event {
329            Event::LeftMouseDragged { position } => {
330                window_state_borrow.synthetic_drag_counter += 1;
331                window_state_borrow
332                    .executor
333                    .spawn(synthetic_drag(
334                        weak_window_state,
335                        window_state_borrow.synthetic_drag_counter,
336                        position,
337                    ))
338                    .detach();
339            }
340            Event::LeftMouseUp { .. } => {
341                window_state_borrow.synthetic_drag_counter += 1;
342            }
343            _ => {}
344        }
345
346        if let Some(mut callback) = window_state_borrow.event_callback.take() {
347            drop(window_state_borrow);
348            callback(event);
349            window_state.borrow_mut().event_callback = Some(callback);
350        }
351    }
352}
353
354extern "C" fn send_event(this: &Object, _: Sel, native_event: id) {
355    unsafe {
356        let () = msg_send![super(this, class!(NSWindow)), sendEvent: native_event];
357    }
358}
359
360extern "C" fn make_backing_layer(this: &Object, _: Sel) -> id {
361    let window_state = unsafe { get_window_state(this) };
362    let window_state = window_state.as_ref().borrow();
363    window_state.layer
364}
365
366extern "C" fn view_did_change_backing_properties(this: &Object, _: Sel) {
367    let window_state = unsafe { get_window_state(this) };
368    let mut window_state = window_state.as_ref().borrow_mut();
369
370    unsafe {
371        let _: () =
372            msg_send![window_state.layer, setContentsScale: window_state.scale_factor() as f64];
373    }
374
375    if let Some(mut callback) = window_state.resize_callback.take() {
376        callback(&mut *window_state);
377        window_state.resize_callback = Some(callback);
378    };
379}
380
381extern "C" fn set_frame_size(this: &Object, _: Sel, size: NSSize) {
382    let window_state = unsafe { get_window_state(this) };
383    let mut window_state = window_state.as_ref().borrow_mut();
384
385    if window_state.size() == vec2f(size.width as f32, size.height as f32) {
386        return;
387    }
388
389    unsafe {
390        let _: () = msg_send![super(this, class!(NSView)), setFrameSize: size];
391    }
392
393    let scale_factor = window_state.scale_factor() as f64;
394    let drawable_size: NSSize = NSSize {
395        width: size.width * scale_factor,
396        height: size.height * scale_factor,
397    };
398
399    unsafe {
400        let _: () = msg_send![window_state.layer, setDrawableSize: drawable_size];
401    }
402
403    if let Some(mut callback) = window_state.resize_callback.take() {
404        callback(&mut *window_state);
405        window_state.resize_callback = Some(callback);
406    };
407}
408
409extern "C" fn display_layer(this: &Object, _: Sel, _: id) {
410    unsafe {
411        let window_state = get_window_state(this);
412        let mut window_state = window_state.as_ref().borrow_mut();
413
414        if let Some(scene) = window_state.scene_to_render.take() {
415            let drawable: &metal::MetalDrawableRef = msg_send![window_state.layer, nextDrawable];
416            let command_queue = window_state.command_queue.clone();
417            let command_buffer = command_queue.new_command_buffer();
418
419            let size = window_state.size();
420            let scale_factor = window_state.scale_factor();
421
422            window_state.renderer.render(
423                &scene,
424                size * scale_factor,
425                command_buffer,
426                drawable.texture(),
427            );
428
429            command_buffer.commit();
430            command_buffer.wait_until_completed();
431            drawable.present();
432        };
433    }
434}
435
436async fn synthetic_drag(
437    window_state: Weak<RefCell<WindowState>>,
438    drag_id: usize,
439    position: Vector2F,
440) {
441    loop {
442        Timer::after(Duration::from_millis(16)).await;
443        if let Some(window_state) = window_state.upgrade() {
444            let mut window_state_borrow = window_state.borrow_mut();
445            if window_state_borrow.synthetic_drag_counter == drag_id {
446                if let Some(mut callback) = window_state_borrow.event_callback.take() {
447                    drop(window_state_borrow);
448                    callback(Event::LeftMouseDragged { position });
449                    window_state.borrow_mut().event_callback = Some(callback);
450                }
451            } else {
452                break;
453            }
454        }
455    }
456}