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 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    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    device: metal::Device,
130    layer: id,
131}
132
133pub struct RenderContext<'a> {
134    pub drawable_size: Vector2F,
135    pub device: &'a metal::Device,
136    pub command_encoder: &'a metal::RenderCommandEncoderRef,
137}
138
139impl Window {
140    pub fn open(
141        options: platform::WindowOptions,
142        executor: Rc<executor::Foreground>,
143    ) -> Result<Self> {
144        const PIXEL_FORMAT: metal::MTLPixelFormat = metal::MTLPixelFormat::BGRA8Unorm;
145
146        unsafe {
147            let pool = NSAutoreleasePool::new(nil);
148
149            let frame = options.bounds.to_ns_rect();
150            let style_mask = NSWindowStyleMask::NSClosableWindowMask
151                | NSWindowStyleMask::NSMiniaturizableWindowMask
152                | NSWindowStyleMask::NSResizableWindowMask
153                | NSWindowStyleMask::NSTitledWindowMask;
154
155            let native_window: id = msg_send![WINDOW_CLASS, alloc];
156            let native_window = native_window.initWithContentRect_styleMask_backing_defer_(
157                frame,
158                style_mask,
159                NSBackingStoreBuffered,
160                NO,
161            );
162
163            if native_window == nil {
164                return Err(anyhow!("window returned nil from initializer"));
165            }
166
167            let device = metal::Device::system_default()
168                .ok_or_else(|| anyhow!("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            if native_view == nil {
185                return Err(anyhow!("view return nil from initializer"));
186            }
187
188            let window = Self(Rc::new(RefCell::new(WindowState {
189                native_window,
190                event_callback: None,
191                resize_callback: None,
192                synthetic_drag_counter: 0,
193                executor,
194                scene_to_render: Default::default(),
195                renderer: Renderer::new(&device, PIXEL_FORMAT)?,
196                command_queue: device.new_command_queue(),
197                device,
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            Ok(window)
238        }
239    }
240
241    pub fn zoom(&self) {
242        unsafe {
243            self.0.as_ref().borrow().native_window.performZoom_(nil);
244        }
245    }
246}
247
248impl Drop for Window {
249    fn drop(&mut self) {
250        unsafe {
251            self.0.as_ref().borrow().native_window.close();
252        }
253    }
254}
255
256impl platform::Window for Window {
257    fn on_event(&mut self, callback: Box<dyn FnMut(Event)>) {
258        self.0.as_ref().borrow_mut().event_callback = Some(callback);
259    }
260
261    fn on_resize(&mut self, callback: Box<dyn FnMut(&mut dyn platform::WindowContext)>) {
262        self.0.as_ref().borrow_mut().resize_callback = Some(callback);
263    }
264}
265
266impl platform::WindowContext for Window {
267    fn size(&self) -> Vector2F {
268        self.0.as_ref().borrow().size()
269    }
270
271    fn scale_factor(&self) -> f32 {
272        self.0.as_ref().borrow().scale_factor()
273    }
274
275    fn present_scene(&mut self, scene: Scene) {
276        self.0.as_ref().borrow_mut().present_scene(scene);
277    }
278}
279
280impl platform::WindowContext for WindowState {
281    fn size(&self) -> Vector2F {
282        let NSSize { width, height, .. } =
283            unsafe { NSView::frame(self.native_window.contentView()) }.size;
284        vec2f(width as f32, height as f32)
285    }
286
287    fn scale_factor(&self) -> f32 {
288        unsafe {
289            let screen: id = msg_send![self.native_window, screen];
290            NSScreen::backingScaleFactor(screen) as f32
291        }
292    }
293
294    fn present_scene(&mut self, scene: Scene) {
295        log::info!("present scene");
296        self.scene_to_render = Some(scene);
297        unsafe {
298            let _: () = msg_send![self.native_window.contentView(), setNeedsDisplay: YES];
299        }
300    }
301}
302
303unsafe fn get_window_state(object: &Object) -> Rc<RefCell<WindowState>> {
304    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
305    let rc1 = Rc::from_raw(raw as *mut RefCell<WindowState>);
306    let rc2 = rc1.clone();
307    mem::forget(rc1);
308    rc2
309}
310
311unsafe fn drop_window_state(object: &Object) {
312    let raw: *mut c_void = *object.get_ivar(WINDOW_STATE_IVAR);
313    Rc::from_raw(raw as *mut WindowState);
314}
315
316extern "C" fn yes(_: &Object, _: Sel) -> BOOL {
317    YES
318}
319
320extern "C" fn dealloc_window(this: &Object, _: Sel) {
321    unsafe {
322        drop_window_state(this);
323        let () = msg_send![super(this, class!(NSWindow)), dealloc];
324    }
325}
326
327extern "C" fn dealloc_view(this: &Object, _: Sel) {
328    unsafe {
329        drop_window_state(this);
330        let () = msg_send![super(this, class!(NSView)), dealloc];
331    }
332}
333
334extern "C" fn handle_view_event(this: &Object, _: Sel, native_event: id) {
335    let window_state = unsafe { get_window_state(this) };
336    let weak_window_state = Rc::downgrade(&window_state);
337    let mut window_state_borrow = window_state.as_ref().borrow_mut();
338
339    let event = unsafe { Event::from_native(native_event, Some(window_state_borrow.size().y())) };
340
341    if let Some(event) = event {
342        match event {
343            Event::LeftMouseDragged { position } => {
344                window_state_borrow.synthetic_drag_counter += 1;
345                window_state_borrow
346                    .executor
347                    .spawn(synthetic_drag(
348                        weak_window_state,
349                        window_state_borrow.synthetic_drag_counter,
350                        position,
351                    ))
352                    .detach();
353            }
354            Event::LeftMouseUp { .. } => {
355                window_state_borrow.synthetic_drag_counter += 1;
356            }
357            _ => {}
358        }
359
360        if let Some(mut callback) = window_state_borrow.event_callback.take() {
361            drop(window_state_borrow);
362            callback(event);
363            window_state.borrow_mut().event_callback = Some(callback);
364        }
365    }
366}
367
368extern "C" fn send_event(this: &Object, _: Sel, native_event: id) {
369    unsafe {
370        let () = msg_send![super(this, class!(NSWindow)), sendEvent: native_event];
371    }
372}
373
374extern "C" fn make_backing_layer(this: &Object, _: Sel) -> id {
375    let window_state = unsafe { get_window_state(this) };
376    let window_state = window_state.as_ref().borrow();
377    window_state.layer
378}
379
380extern "C" fn view_did_change_backing_properties(this: &Object, _: Sel) {
381    let window_state = unsafe { get_window_state(this) };
382    let mut window_state = window_state.as_ref().borrow_mut();
383
384    unsafe {
385        let _: () =
386            msg_send![window_state.layer, setContentsScale: window_state.scale_factor() as f64];
387    }
388
389    if let Some(mut callback) = window_state.resize_callback.take() {
390        callback(&mut *window_state);
391        window_state.resize_callback = Some(callback);
392    };
393}
394
395extern "C" fn set_frame_size(this: &Object, _: Sel, size: NSSize) {
396    let window_state = unsafe { get_window_state(this) };
397    let mut window_state = window_state.as_ref().borrow_mut();
398
399    if window_state.size() == vec2f(size.width as f32, size.height as f32) {
400        return;
401    }
402
403    unsafe {
404        let _: () = msg_send![super(this, class!(NSView)), setFrameSize: size];
405    }
406
407    let scale_factor = window_state.scale_factor() as f64;
408    let drawable_size: NSSize = NSSize {
409        width: size.width * scale_factor,
410        height: size.height * scale_factor,
411    };
412
413    unsafe {
414        let _: () = msg_send![window_state.layer, setDrawableSize: drawable_size];
415    }
416
417    if let Some(mut callback) = window_state.resize_callback.take() {
418        callback(&mut *window_state);
419        window_state.resize_callback = Some(callback);
420    };
421}
422
423extern "C" fn display_layer(this: &Object, _: Sel, _: id) {
424    log::info!("display layer");
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}