window.rs

  1use crate::{
  2    executor,
  3    geometry::vector::Vector2F,
  4    platform::{self, Event, WindowContext},
  5    util::post_inc,
  6    Scene,
  7};
  8use anyhow::{anyhow, Result};
  9use cocoa::{
 10    appkit::{
 11        NSBackingStoreBuffered, NSScreen, NSView, NSViewHeightSizable, NSViewWidthSizable,
 12        NSWindow, NSWindowStyleMask,
 13    },
 14    base::{id, nil},
 15    foundation::{NSAutoreleasePool, NSSize, NSString},
 16    quartzcore::AutoresizingMask,
 17};
 18use ctor::ctor;
 19use foreign_types::ForeignType as _;
 20use metal::{MTLClearColor, MTLLoadAction, MTLStoreAction};
 21use objc::{
 22    class,
 23    declare::ClassDecl,
 24    msg_send,
 25    runtime::{Class, Object, Protocol, Sel, BOOL, NO, YES},
 26    sel, sel_impl,
 27};
 28use pathfinder_geometry::vector::vec2f;
 29use smol::Timer;
 30use std::{
 31    cell::RefCell,
 32    ffi::c_void,
 33    mem, ptr,
 34    rc::Rc,
 35    time::{Duration, Instant},
 36};
 37
 38use super::{geometry::RectFExt, renderer::Renderer};
 39
 40const WINDOW_STATE_IVAR: &'static str = "windowState";
 41
 42static mut WINDOW_CLASS: *const Class = ptr::null();
 43static mut VIEW_CLASS: *const Class = ptr::null();
 44
 45#[ctor]
 46unsafe fn build_classes() {
 47    WINDOW_CLASS = {
 48        let mut decl = ClassDecl::new("GPUIWindow", class!(NSWindow)).unwrap();
 49        decl.add_ivar::<*mut c_void>(WINDOW_STATE_IVAR);
 50        decl.add_method(sel!(dealloc), dealloc_window as extern "C" fn(&Object, Sel));
 51        decl.add_method(
 52            sel!(canBecomeMainWindow),
 53            yes as extern "C" fn(&Object, Sel) -> BOOL,
 54        );
 55        decl.add_method(
 56            sel!(canBecomeKeyWindow),
 57            yes as extern "C" fn(&Object, Sel) -> BOOL,
 58        );
 59        decl.add_method(
 60            sel!(sendEvent:),
 61            send_event as extern "C" fn(&Object, Sel, id),
 62        );
 63        decl.register()
 64    };
 65
 66    VIEW_CLASS = {
 67        let mut decl = ClassDecl::new("GPUIView", class!(NSView)).unwrap();
 68        decl.add_ivar::<*mut c_void>(WINDOW_STATE_IVAR);
 69
 70        decl.add_method(sel!(dealloc), dealloc_view as extern "C" fn(&Object, Sel));
 71
 72        decl.add_method(
 73            sel!(keyDown:),
 74            handle_view_event as extern "C" fn(&Object, Sel, id),
 75        );
 76        decl.add_method(
 77            sel!(mouseDown:),
 78            handle_view_event as extern "C" fn(&Object, Sel, id),
 79        );
 80        decl.add_method(
 81            sel!(mouseUp:),
 82            handle_view_event as extern "C" fn(&Object, Sel, id),
 83        );
 84        decl.add_method(
 85            sel!(mouseDragged:),
 86            handle_view_event as extern "C" fn(&Object, Sel, id),
 87        );
 88        decl.add_method(
 89            sel!(scrollWheel:),
 90            handle_view_event as extern "C" fn(&Object, Sel, id),
 91        );
 92
 93        decl.add_protocol(Protocol::get("CALayerDelegate").unwrap());
 94        decl.add_method(
 95            sel!(makeBackingLayer),
 96            make_backing_layer as extern "C" fn(&Object, Sel) -> id,
 97        );
 98        decl.add_method(
 99            sel!(viewDidChangeBackingProperties),
100            view_did_change_backing_properties as extern "C" fn(&Object, Sel),
101        );
102        decl.add_method(
103            sel!(setFrameSize:),
104            set_frame_size as extern "C" fn(&Object, Sel, NSSize),
105        );
106        decl.add_method(
107            sel!(displayLayer:),
108            display_layer as extern "C" fn(&Object, Sel, id),
109        );
110
111        decl.register()
112    };
113}
114
115pub struct Window(Rc<RefCell<WindowState>>);
116
117struct WindowState {
118    native_window: id,
119    event_callback: Option<Box<dyn FnMut(Event, &mut dyn platform::WindowContext)>>,
120    resize_callback: Option<Box<dyn FnMut(&mut dyn platform::WindowContext)>>,
121    synthetic_drag_counter: usize,
122    executor: Rc<executor::Foreground>,
123    scene_to_render: Option<Scene>,
124    renderer: Renderer,
125    command_queue: metal::CommandQueue,
126    device: metal::Device,
127    layer: id,
128}
129
130pub struct RenderContext<'a> {
131    pub drawable_size: Vector2F,
132    pub device: &'a metal::Device,
133    pub command_encoder: &'a metal::RenderCommandEncoderRef,
134}
135
136impl Window {
137    pub fn open(
138        options: platform::WindowOptions,
139        executor: Rc<executor::Foreground>,
140    ) -> Result<Self> {
141        const PIXEL_FORMAT: metal::MTLPixelFormat = metal::MTLPixelFormat::BGRA8Unorm;
142
143        unsafe {
144            let pool = NSAutoreleasePool::new(nil);
145
146            let frame = options.bounds.to_ns_rect();
147            let style_mask = NSWindowStyleMask::NSClosableWindowMask
148                | NSWindowStyleMask::NSMiniaturizableWindowMask
149                | NSWindowStyleMask::NSResizableWindowMask
150                | NSWindowStyleMask::NSTitledWindowMask;
151
152            let native_window: id = msg_send![WINDOW_CLASS, alloc];
153            let native_window = native_window.initWithContentRect_styleMask_backing_defer_(
154                frame,
155                style_mask,
156                NSBackingStoreBuffered,
157                NO,
158            );
159
160            if native_window == nil {
161                return Err(anyhow!("window returned nil from initializer"));
162            }
163
164            let device = metal::Device::system_default()
165                .ok_or_else(|| anyhow!("could not find default metal device"))?;
166
167            let layer: id = msg_send![class!(CAMetalLayer), layer];
168            let _: () = msg_send![layer, setDevice: device.as_ptr()];
169            let _: () = msg_send![layer, setPixelFormat: PIXEL_FORMAT];
170            let _: () = msg_send![layer, setAllowsNextDrawableTimeout: NO];
171            let _: () = msg_send![layer, setNeedsDisplayOnBoundsChange: YES];
172            let _: () = msg_send![layer, setPresentsWithTransaction: YES];
173            let _: () = msg_send![
174                layer,
175                setAutoresizingMask: AutoresizingMask::WIDTH_SIZABLE
176                    | AutoresizingMask::HEIGHT_SIZABLE
177            ];
178
179            let native_view: id = msg_send![VIEW_CLASS, alloc];
180            let native_view = NSView::init(native_view);
181            if native_view == nil {
182                return Err(anyhow!("view return nil from initializer"));
183            }
184
185            let window = Self(Rc::new(RefCell::new(WindowState {
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, PIXEL_FORMAT)?,
193                command_queue: device.new_command_queue(),
194                device,
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
222            native_view.layer().setBackgroundColor_(
223                msg_send![class!(NSColor), colorWithRed:1.0 green:0.0 blue:0.0 alpha:1.0],
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            Ok(window)
235        }
236    }
237
238    pub fn zoom(&self) {
239        unsafe {
240            self.0.as_ref().borrow().native_window.performZoom_(nil);
241        }
242    }
243}
244
245impl Drop for Window {
246    fn drop(&mut self) {
247        unsafe {
248            self.0.as_ref().borrow().native_window.close();
249        }
250    }
251}
252
253impl platform::Window for Window {
254    fn on_event(&mut self, callback: Box<dyn FnMut(Event, &mut dyn platform::WindowContext)>) {
255        self.0.as_ref().borrow_mut().event_callback = Some(callback);
256    }
257
258    fn on_resize(&mut self, callback: Box<dyn FnMut(&mut dyn platform::WindowContext)>) {
259        self.0.as_ref().borrow_mut().resize_callback = Some(callback);
260    }
261}
262
263impl platform::WindowContext for Window {
264    fn size(&self) -> Vector2F {
265        self.0.as_ref().borrow().size()
266    }
267
268    fn scale_factor(&self) -> f32 {
269        self.0.as_ref().borrow().scale_factor()
270    }
271
272    fn present_scene(&mut self, scene: Scene) {
273        self.0.as_ref().borrow_mut().present_scene(scene);
274    }
275}
276
277impl platform::WindowContext for WindowState {
278    fn size(&self) -> Vector2F {
279        let NSSize { width, height, .. } =
280            unsafe { NSView::frame(self.native_window.contentView()) }.size;
281        vec2f(width as f32, height as f32)
282    }
283
284    fn scale_factor(&self) -> f32 {
285        unsafe {
286            let screen: id = msg_send![self.native_window, screen];
287            NSScreen::backingScaleFactor(screen) as f32
288        }
289    }
290
291    fn present_scene(&mut self, scene: Scene) {
292        self.scene_to_render = Some(scene);
293        unsafe {
294            let _: () = msg_send![self.native_window.contentView(), setNeedsDisplay: YES];
295        }
296    }
297}
298
299unsafe fn get_window_state(object: &Object) -> Rc<RefCell<WindowState>> {
300    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
301    let rc1 = Rc::from_raw(raw as *mut RefCell<WindowState>);
302    let rc2 = rc1.clone();
303    mem::forget(rc1);
304    rc2
305}
306
307unsafe fn drop_window_state(object: &Object) {
308    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
309    Rc::from_raw(raw as *mut WindowState);
310}
311
312extern "C" fn yes(_: &Object, _: Sel) -> BOOL {
313    YES
314}
315
316extern "C" fn dealloc_window(this: &Object, _: Sel) {
317    unsafe {
318        drop_window_state(this);
319        let () = msg_send![super(this, class!(NSWindow)), dealloc];
320    }
321}
322
323extern "C" fn dealloc_view(this: &Object, _: Sel) {
324    unsafe {
325        drop_window_state(this);
326        let () = msg_send![super(this, class!(NSView)), dealloc];
327    }
328}
329
330extern "C" fn handle_view_event(this: &Object, _: Sel, native_event: id) {
331    let window_state = unsafe { get_window_state(this) };
332    let mut window_state_borrow = window_state.as_ref().borrow_mut();
333
334    let event = unsafe { Event::from_native(native_event, Some(window_state_borrow.size().y())) };
335
336    if let Some(event) = event {
337        match event {
338            Event::LeftMouseDragged { position } => {
339                schedule_synthetic_drag(&&window_state, position)
340            }
341            Event::LeftMouseUp { .. } => {
342                post_inc(&mut window_state_borrow.synthetic_drag_counter);
343            }
344            _ => {}
345        }
346
347        if let Some(mut callback) = window_state_borrow.event_callback.take() {
348            callback(event, &mut *window_state_borrow);
349            window_state_borrow.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    log::info!("display layer");
411    unsafe {
412        let window_state = get_window_state(this);
413        let mut window_state = window_state.as_ref().borrow_mut();
414
415        if let Some(scene) = window_state.scene_to_render.take() {
416            let drawable: &metal::MetalDrawableRef = msg_send![window_state.layer, nextDrawable];
417
418            let render_pass_descriptor = metal::RenderPassDescriptor::new();
419            let color_attachment = render_pass_descriptor
420                .color_attachments()
421                .object_at(0)
422                .unwrap();
423            color_attachment.set_texture(Some(drawable.texture()));
424            color_attachment.set_load_action(MTLLoadAction::Clear);
425            color_attachment.set_store_action(MTLStoreAction::Store);
426            color_attachment.set_clear_color(MTLClearColor::new(0., 0., 0., 1.));
427
428            let command_queue = window_state.command_queue.clone();
429            let command_buffer = command_queue.new_command_buffer();
430            let command_encoder = command_buffer.new_render_command_encoder(render_pass_descriptor);
431
432            let size = window_state.size();
433            let scale_factor = window_state.scale_factor();
434            let device = window_state.device.clone();
435
436            window_state.renderer.render(
437                &scene,
438                &RenderContext {
439                    drawable_size: size * scale_factor,
440                    device: &device,
441                    command_encoder,
442                },
443            );
444
445            command_encoder.end_encoding();
446            command_buffer.commit();
447            command_buffer.wait_until_completed();
448            drawable.present();
449
450            log::info!("present");
451        };
452    }
453}
454
455fn schedule_synthetic_drag(window_state: &Rc<RefCell<WindowState>>, position: Vector2F) {
456    let weak_window_state = Rc::downgrade(window_state);
457    let mut window_state = window_state.as_ref().borrow_mut();
458
459    let drag_id = post_inc(&mut window_state.synthetic_drag_counter);
460    let instant = Instant::now() + Duration::from_millis(16);
461
462    window_state
463        .executor
464        .spawn(async move {
465            Timer::at(instant).await;
466            if let Some(window_state) = weak_window_state.upgrade() {
467                let mut window_state_borrow = window_state.as_ref().borrow_mut();
468                if window_state_borrow.synthetic_drag_counter == drag_id {
469                    if let Some(mut callback) = window_state_borrow.event_callback.take() {
470                        schedule_synthetic_drag(&window_state, position);
471                        callback(
472                            Event::LeftMouseDragged { position },
473                            &mut *window_state_borrow,
474                        );
475                        window_state_borrow.event_callback = Some(callback);
476                    }
477                }
478            }
479        })
480        .detach();
481}