window.rs

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