1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 platform::{CursorStyle, Event},
8 scene::CursorRegion,
9 text_layout::TextLayoutCache,
10 Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AssetCache, ElementBox, Entity,
11 FontSystem, ModelHandle, MouseRegion, MouseRegionId, ReadModel, ReadView, RenderContext,
12 RenderParams, Scene, UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle,
13 WeakViewHandle,
14};
15use pathfinder_geometry::vector::{vec2f, Vector2F};
16use serde_json::json;
17use std::{
18 collections::{HashMap, HashSet},
19 marker::PhantomData,
20 ops::{Deref, DerefMut},
21 sync::Arc,
22};
23
24pub struct Presenter {
25 window_id: usize,
26 pub(crate) rendered_views: HashMap<usize, ElementBox>,
27 parents: HashMap<usize, usize>,
28 cursor_regions: Vec<CursorRegion>,
29 mouse_regions: Vec<MouseRegion>,
30 font_cache: Arc<FontCache>,
31 text_layout_cache: TextLayoutCache,
32 asset_cache: Arc<AssetCache>,
33 last_mouse_moved_event: Option<Event>,
34 hovered_region_ids: HashSet<MouseRegionId>,
35 clicked_region: Option<MouseRegion>,
36 prev_drag_position: Option<Vector2F>,
37 titlebar_height: f32,
38}
39
40impl Presenter {
41 pub fn new(
42 window_id: usize,
43 titlebar_height: f32,
44 font_cache: Arc<FontCache>,
45 text_layout_cache: TextLayoutCache,
46 asset_cache: Arc<AssetCache>,
47 cx: &mut MutableAppContext,
48 ) -> Self {
49 Self {
50 window_id,
51 rendered_views: cx.render_views(window_id, titlebar_height),
52 parents: HashMap::new(),
53 cursor_regions: Default::default(),
54 mouse_regions: Default::default(),
55 font_cache,
56 text_layout_cache,
57 asset_cache,
58 last_mouse_moved_event: None,
59 hovered_region_ids: Default::default(),
60 clicked_region: None,
61 prev_drag_position: None,
62 titlebar_height,
63 }
64 }
65
66 pub fn dispatch_path(&self, app: &AppContext) -> Vec<usize> {
67 if let Some(view_id) = app.focused_view_id(self.window_id) {
68 self.dispatch_path_from(view_id)
69 } else {
70 Vec::new()
71 }
72 }
73
74 pub(crate) fn dispatch_path_from(&self, mut view_id: usize) -> Vec<usize> {
75 let mut path = Vec::new();
76 path.push(view_id);
77 while let Some(parent_id) = self.parents.get(&view_id).copied() {
78 path.push(parent_id);
79 view_id = parent_id;
80 }
81 path.reverse();
82 path
83 }
84
85 pub fn invalidate(
86 &mut self,
87 invalidation: &mut WindowInvalidation,
88 cx: &mut MutableAppContext,
89 ) {
90 cx.start_frame();
91 for view_id in &invalidation.removed {
92 invalidation.updated.remove(&view_id);
93 self.rendered_views.remove(&view_id);
94 self.parents.remove(&view_id);
95 }
96 for view_id in &invalidation.updated {
97 self.rendered_views.insert(
98 *view_id,
99 cx.render_view(RenderParams {
100 window_id: self.window_id,
101 view_id: *view_id,
102 titlebar_height: self.titlebar_height,
103 hovered_region_ids: self.hovered_region_ids.clone(),
104 clicked_region_id: self.clicked_region.as_ref().map(MouseRegion::id),
105 refreshing: false,
106 })
107 .unwrap(),
108 );
109 }
110 }
111
112 pub fn refresh(&mut self, invalidation: &mut WindowInvalidation, cx: &mut MutableAppContext) {
113 self.invalidate(invalidation, cx);
114 for (view_id, view) in &mut self.rendered_views {
115 if !invalidation.updated.contains(view_id) {
116 *view = cx
117 .render_view(RenderParams {
118 window_id: self.window_id,
119 view_id: *view_id,
120 titlebar_height: self.titlebar_height,
121 hovered_region_ids: self.hovered_region_ids.clone(),
122 clicked_region_id: self.clicked_region.as_ref().map(MouseRegion::id),
123 refreshing: true,
124 })
125 .unwrap();
126 }
127 }
128 }
129
130 pub fn build_scene(
131 &mut self,
132 window_size: Vector2F,
133 scale_factor: f32,
134 refreshing: bool,
135 cx: &mut MutableAppContext,
136 ) -> Scene {
137 let mut scene = Scene::new(scale_factor);
138
139 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
140 self.layout(window_size, refreshing, cx);
141 let mut paint_cx = self.build_paint_context(&mut scene, cx);
142 paint_cx.paint(
143 root_view_id,
144 Vector2F::zero(),
145 RectF::new(Vector2F::zero(), window_size),
146 );
147 self.text_layout_cache.finish_frame();
148 self.cursor_regions = scene.cursor_regions();
149 self.mouse_regions = scene.mouse_regions();
150
151 if cx.window_is_active(self.window_id) {
152 if let Some(event) = self.last_mouse_moved_event.clone() {
153 self.dispatch_event(event, cx)
154 }
155 }
156 } else {
157 log::error!("could not find root_view_id for window {}", self.window_id);
158 }
159
160 scene
161 }
162
163 fn layout(&mut self, size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
164 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
165 self.build_layout_context(refreshing, cx)
166 .layout(root_view_id, SizeConstraint::strict(size));
167 }
168 }
169
170 pub fn build_layout_context<'a>(
171 &'a mut self,
172 refreshing: bool,
173 cx: &'a mut MutableAppContext,
174 ) -> LayoutContext<'a> {
175 LayoutContext {
176 rendered_views: &mut self.rendered_views,
177 parents: &mut self.parents,
178 font_cache: &self.font_cache,
179 font_system: cx.platform().fonts(),
180 text_layout_cache: &self.text_layout_cache,
181 asset_cache: &self.asset_cache,
182 view_stack: Vec::new(),
183 refreshing,
184 hovered_region_ids: self.hovered_region_ids.clone(),
185 clicked_region_id: self.clicked_region.as_ref().map(MouseRegion::id),
186 titlebar_height: self.titlebar_height,
187 app: cx,
188 }
189 }
190
191 pub fn build_paint_context<'a>(
192 &'a mut self,
193 scene: &'a mut Scene,
194 cx: &'a mut MutableAppContext,
195 ) -> PaintContext {
196 PaintContext {
197 scene,
198 font_cache: &self.font_cache,
199 text_layout_cache: &self.text_layout_cache,
200 rendered_views: &mut self.rendered_views,
201 view_stack: Vec::new(),
202 app: cx,
203 }
204 }
205
206 pub fn dispatch_event(&mut self, event: Event, cx: &mut MutableAppContext) {
207 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
208 let mut invalidated_views = Vec::new();
209 let mut hovered_regions = Vec::new();
210 let mut unhovered_regions = Vec::new();
211 let mut clicked_region = None;
212 let mut dragged_region = None;
213
214 match event {
215 Event::LeftMouseDown { position, .. } => {
216 for region in self.mouse_regions.iter().rev() {
217 if region.bounds.contains_point(position) {
218 invalidated_views.push(region.view_id);
219 self.clicked_region = Some(region.clone());
220 self.prev_drag_position = Some(position);
221 break;
222 }
223 }
224 }
225 Event::LeftMouseUp {
226 position,
227 click_count,
228 ..
229 } => {
230 self.prev_drag_position.take();
231 if let Some(region) = self.clicked_region.take() {
232 invalidated_views.push(region.view_id);
233 if region.bounds.contains_point(position) {
234 clicked_region = Some((region, position, click_count));
235 }
236 }
237 }
238 Event::MouseMoved {
239 position,
240 left_mouse_down,
241 } => {
242 self.last_mouse_moved_event = Some(event.clone());
243
244 if !left_mouse_down {
245 let mut style_to_assign = CursorStyle::Arrow;
246 for region in self.cursor_regions.iter().rev() {
247 if region.bounds.contains_point(position) {
248 style_to_assign = region.style;
249 break;
250 }
251 }
252 cx.platform().set_cursor_style(style_to_assign);
253
254 for region in self.mouse_regions.iter().rev() {
255 let region_id = region.id();
256 if region.bounds.contains_point(position) {
257 if !self.hovered_region_ids.contains(®ion_id) {
258 invalidated_views.push(region.view_id);
259 hovered_regions.push(region.clone());
260 self.hovered_region_ids.insert(region_id);
261 }
262 } else {
263 if self.hovered_region_ids.contains(®ion_id) {
264 invalidated_views.push(region.view_id);
265 unhovered_regions.push(region.clone());
266 self.hovered_region_ids.remove(®ion_id);
267 }
268 }
269 }
270 }
271 }
272 Event::LeftMouseDragged { position } => {
273 if let Some((clicked_region, prev_drag_position)) = self
274 .clicked_region
275 .as_ref()
276 .zip(self.prev_drag_position.as_mut())
277 {
278 dragged_region =
279 Some((clicked_region.clone(), position - *prev_drag_position));
280 *prev_drag_position = position;
281 }
282
283 self.last_mouse_moved_event = Some(Event::MouseMoved {
284 position,
285 left_mouse_down: true,
286 });
287 }
288 _ => {}
289 }
290
291 let mut event_cx = self.build_event_context(cx);
292 for unhovered_region in unhovered_regions {
293 if let Some(hover_callback) = unhovered_region.hover {
294 event_cx.with_current_view(unhovered_region.view_id, |event_cx| {
295 hover_callback(false, event_cx);
296 })
297 }
298 }
299
300 for hovered_region in hovered_regions {
301 if let Some(hover_callback) = hovered_region.hover {
302 event_cx.with_current_view(hovered_region.view_id, |event_cx| {
303 hover_callback(true, event_cx);
304 })
305 }
306 }
307
308 if let Some((clicked_region, position, click_count)) = clicked_region {
309 if let Some(click_callback) = clicked_region.click {
310 event_cx.with_current_view(clicked_region.view_id, |event_cx| {
311 click_callback(position, click_count, event_cx);
312 })
313 }
314 }
315
316 if let Some((dragged_region, delta)) = dragged_region {
317 if let Some(drag_callback) = dragged_region.drag {
318 event_cx.with_current_view(dragged_region.view_id, |event_cx| {
319 drag_callback(delta, event_cx);
320 })
321 }
322 }
323
324 event_cx.dispatch_event(root_view_id, &event);
325
326 invalidated_views.extend(event_cx.invalidated_views);
327 let dispatch_directives = event_cx.dispatched_actions;
328
329 for view_id in invalidated_views {
330 cx.notify_view(self.window_id, view_id);
331 }
332 for directive in dispatch_directives {
333 cx.dispatch_action_any(self.window_id, &directive.path, directive.action.as_ref());
334 }
335 }
336 }
337
338 pub fn build_event_context<'a>(
339 &'a mut self,
340 cx: &'a mut MutableAppContext,
341 ) -> EventContext<'a> {
342 EventContext {
343 rendered_views: &mut self.rendered_views,
344 dispatched_actions: Default::default(),
345 font_cache: &self.font_cache,
346 text_layout_cache: &self.text_layout_cache,
347 view_stack: Default::default(),
348 invalidated_views: Default::default(),
349 notify_count: 0,
350 app: cx,
351 }
352 }
353
354 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
355 let view = cx.root_view(self.window_id)?;
356 Some(json!({
357 "root_view": view.debug_json(cx),
358 "root_element": self.rendered_views.get(&view.id())
359 .map(|root_element| {
360 root_element.debug(&DebugContext {
361 rendered_views: &self.rendered_views,
362 font_cache: &self.font_cache,
363 app: cx,
364 })
365 })
366 }))
367 }
368}
369
370pub struct DispatchDirective {
371 pub path: Vec<usize>,
372 pub action: Box<dyn Action>,
373}
374
375pub struct LayoutContext<'a> {
376 rendered_views: &'a mut HashMap<usize, ElementBox>,
377 parents: &'a mut HashMap<usize, usize>,
378 view_stack: Vec<usize>,
379 pub font_cache: &'a Arc<FontCache>,
380 pub font_system: Arc<dyn FontSystem>,
381 pub text_layout_cache: &'a TextLayoutCache,
382 pub asset_cache: &'a AssetCache,
383 pub app: &'a mut MutableAppContext,
384 pub refreshing: bool,
385 titlebar_height: f32,
386 hovered_region_ids: HashSet<MouseRegionId>,
387 clicked_region_id: Option<MouseRegionId>,
388}
389
390impl<'a> LayoutContext<'a> {
391 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
392 if let Some(parent_id) = self.view_stack.last() {
393 self.parents.insert(view_id, *parent_id);
394 }
395 self.view_stack.push(view_id);
396 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
397 let size = rendered_view.layout(constraint, self);
398 self.rendered_views.insert(view_id, rendered_view);
399 self.view_stack.pop();
400 size
401 }
402
403 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
404 where
405 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
406 V: View,
407 {
408 handle.update(self.app, |view, cx| {
409 let mut render_cx = RenderContext {
410 app: cx,
411 window_id: handle.window_id(),
412 view_id: handle.id(),
413 view_type: PhantomData,
414 titlebar_height: self.titlebar_height,
415 hovered_region_ids: self.hovered_region_ids.clone(),
416 clicked_region_id: self.clicked_region_id,
417 refreshing: self.refreshing,
418 };
419 f(view, &mut render_cx)
420 })
421 }
422}
423
424impl<'a> Deref for LayoutContext<'a> {
425 type Target = MutableAppContext;
426
427 fn deref(&self) -> &Self::Target {
428 self.app
429 }
430}
431
432impl<'a> DerefMut for LayoutContext<'a> {
433 fn deref_mut(&mut self) -> &mut Self::Target {
434 self.app
435 }
436}
437
438impl<'a> ReadView for LayoutContext<'a> {
439 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
440 self.app.read_view(handle)
441 }
442}
443
444impl<'a> ReadModel for LayoutContext<'a> {
445 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
446 self.app.read_model(handle)
447 }
448}
449
450impl<'a> UpgradeModelHandle for LayoutContext<'a> {
451 fn upgrade_model_handle<T: Entity>(
452 &self,
453 handle: &WeakModelHandle<T>,
454 ) -> Option<ModelHandle<T>> {
455 self.app.upgrade_model_handle(handle)
456 }
457
458 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
459 self.app.model_handle_is_upgradable(handle)
460 }
461
462 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
463 self.app.upgrade_any_model_handle(handle)
464 }
465}
466
467impl<'a> UpgradeViewHandle for LayoutContext<'a> {
468 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
469 self.app.upgrade_view_handle(handle)
470 }
471
472 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
473 self.app.upgrade_any_view_handle(handle)
474 }
475}
476
477pub struct PaintContext<'a> {
478 rendered_views: &'a mut HashMap<usize, ElementBox>,
479 view_stack: Vec<usize>,
480 pub scene: &'a mut Scene,
481 pub font_cache: &'a FontCache,
482 pub text_layout_cache: &'a TextLayoutCache,
483 pub app: &'a AppContext,
484}
485
486impl<'a> PaintContext<'a> {
487 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
488 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
489 self.view_stack.push(view_id);
490 tree.paint(origin, visible_bounds, self);
491 self.rendered_views.insert(view_id, tree);
492 self.view_stack.pop();
493 }
494 }
495
496 pub fn current_view_id(&self) -> usize {
497 *self.view_stack.last().unwrap()
498 }
499}
500
501impl<'a> Deref for PaintContext<'a> {
502 type Target = AppContext;
503
504 fn deref(&self) -> &Self::Target {
505 self.app
506 }
507}
508
509pub struct EventContext<'a> {
510 rendered_views: &'a mut HashMap<usize, ElementBox>,
511 dispatched_actions: Vec<DispatchDirective>,
512 pub font_cache: &'a FontCache,
513 pub text_layout_cache: &'a TextLayoutCache,
514 pub app: &'a mut MutableAppContext,
515 pub notify_count: usize,
516 view_stack: Vec<usize>,
517 invalidated_views: HashSet<usize>,
518}
519
520impl<'a> EventContext<'a> {
521 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
522 if let Some(mut element) = self.rendered_views.remove(&view_id) {
523 let result =
524 self.with_current_view(view_id, |this| element.dispatch_event(event, this));
525 self.rendered_views.insert(view_id, element);
526 result
527 } else {
528 false
529 }
530 }
531
532 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
533 where
534 F: FnOnce(&mut Self) -> T,
535 {
536 self.view_stack.push(view_id);
537 let result = f(self);
538 self.view_stack.pop();
539 result
540 }
541
542 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
543 self.dispatched_actions.push(DispatchDirective {
544 path: self.view_stack.clone(),
545 action,
546 });
547 }
548
549 pub fn dispatch_action<A: Action>(&mut self, action: A) {
550 self.dispatch_any_action(Box::new(action));
551 }
552
553 pub fn notify(&mut self) {
554 self.notify_count += 1;
555 if let Some(view_id) = self.view_stack.last() {
556 self.invalidated_views.insert(*view_id);
557 }
558 }
559
560 pub fn notify_count(&self) -> usize {
561 self.notify_count
562 }
563}
564
565impl<'a> Deref for EventContext<'a> {
566 type Target = MutableAppContext;
567
568 fn deref(&self) -> &Self::Target {
569 self.app
570 }
571}
572
573impl<'a> DerefMut for EventContext<'a> {
574 fn deref_mut(&mut self) -> &mut Self::Target {
575 self.app
576 }
577}
578
579pub struct DebugContext<'a> {
580 rendered_views: &'a HashMap<usize, ElementBox>,
581 pub font_cache: &'a FontCache,
582 pub app: &'a AppContext,
583}
584
585#[derive(Clone, Copy, Debug, Eq, PartialEq)]
586pub enum Axis {
587 Horizontal,
588 Vertical,
589}
590
591impl Axis {
592 pub fn invert(self) -> Self {
593 match self {
594 Self::Horizontal => Self::Vertical,
595 Self::Vertical => Self::Horizontal,
596 }
597 }
598}
599
600impl ToJson for Axis {
601 fn to_json(&self) -> serde_json::Value {
602 match self {
603 Axis::Horizontal => json!("horizontal"),
604 Axis::Vertical => json!("vertical"),
605 }
606 }
607}
608
609pub trait Vector2FExt {
610 fn along(self, axis: Axis) -> f32;
611}
612
613impl Vector2FExt for Vector2F {
614 fn along(self, axis: Axis) -> f32 {
615 match axis {
616 Axis::Horizontal => self.x(),
617 Axis::Vertical => self.y(),
618 }
619 }
620}
621
622#[derive(Copy, Clone, Debug)]
623pub struct SizeConstraint {
624 pub min: Vector2F,
625 pub max: Vector2F,
626}
627
628impl SizeConstraint {
629 pub fn new(min: Vector2F, max: Vector2F) -> Self {
630 Self { min, max }
631 }
632
633 pub fn strict(size: Vector2F) -> Self {
634 Self {
635 min: size,
636 max: size,
637 }
638 }
639
640 pub fn strict_along(axis: Axis, max: f32) -> Self {
641 match axis {
642 Axis::Horizontal => Self {
643 min: vec2f(max, 0.0),
644 max: vec2f(max, f32::INFINITY),
645 },
646 Axis::Vertical => Self {
647 min: vec2f(0.0, max),
648 max: vec2f(f32::INFINITY, max),
649 },
650 }
651 }
652
653 pub fn max_along(&self, axis: Axis) -> f32 {
654 match axis {
655 Axis::Horizontal => self.max.x(),
656 Axis::Vertical => self.max.y(),
657 }
658 }
659
660 pub fn min_along(&self, axis: Axis) -> f32 {
661 match axis {
662 Axis::Horizontal => self.min.x(),
663 Axis::Vertical => self.min.y(),
664 }
665 }
666
667 pub fn constrain(&self, size: Vector2F) -> Vector2F {
668 vec2f(
669 size.x().min(self.max.x()).max(self.min.x()),
670 size.y().min(self.max.y()).max(self.min.y()),
671 )
672 }
673}
674
675impl ToJson for SizeConstraint {
676 fn to_json(&self) -> serde_json::Value {
677 json!({
678 "min": self.min.to_json(),
679 "max": self.max.to_json(),
680 })
681 }
682}
683
684pub struct ChildView {
685 view: AnyViewHandle,
686}
687
688impl ChildView {
689 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
690 Self { view: view.into() }
691 }
692}
693
694impl Element for ChildView {
695 type LayoutState = ();
696 type PaintState = ();
697
698 fn layout(
699 &mut self,
700 constraint: SizeConstraint,
701 cx: &mut LayoutContext,
702 ) -> (Vector2F, Self::LayoutState) {
703 let size = cx.layout(self.view.id(), constraint);
704 (size, ())
705 }
706
707 fn paint(
708 &mut self,
709 bounds: RectF,
710 visible_bounds: RectF,
711 _: &mut Self::LayoutState,
712 cx: &mut PaintContext,
713 ) -> Self::PaintState {
714 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
715 }
716
717 fn dispatch_event(
718 &mut self,
719 event: &Event,
720 _: RectF,
721 _: RectF,
722 _: &mut Self::LayoutState,
723 _: &mut Self::PaintState,
724 cx: &mut EventContext,
725 ) -> bool {
726 cx.dispatch_event(self.view.id(), event)
727 }
728
729 fn debug(
730 &self,
731 bounds: RectF,
732 _: &Self::LayoutState,
733 _: &Self::PaintState,
734 cx: &DebugContext,
735 ) -> serde_json::Value {
736 json!({
737 "type": "ChildView",
738 "view_id": self.view.id(),
739 "bounds": bounds.to_json(),
740 "view": self.view.debug_json(cx.app),
741 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
742 view.debug(cx)
743 } else {
744 json!(null)
745 }
746 })
747 }
748}