1use crate::{
2 app::{AppContext, MutableAppContext, WindowInvalidation},
3 elements::Element,
4 font_cache::FontCache,
5 geometry::rect::RectF,
6 json::{self, ToJson},
7 keymap::Keystroke,
8 platform::{CursorStyle, Event},
9 scene::{CursorRegion, MouseRegionEvent},
10 text_layout::TextLayoutCache,
11 Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AssetCache, ElementBox, Entity,
12 FontSystem, ModelHandle, MouseButtonEvent, MouseMovedEvent, MouseRegion, MouseRegionId,
13 ReadModel, ReadView, RenderContext, RenderParams, Scene, UpgradeModelHandle, UpgradeViewHandle,
14 View, ViewHandle, WeakModelHandle, WeakViewHandle,
15};
16use pathfinder_geometry::vector::{vec2f, Vector2F};
17use serde_json::json;
18use smallvec::SmallVec;
19use std::{
20 collections::{HashMap, HashSet},
21 marker::PhantomData,
22 ops::{Deref, DerefMut, Range},
23 sync::Arc,
24};
25
26pub struct Presenter {
27 window_id: usize,
28 pub(crate) rendered_views: HashMap<usize, ElementBox>,
29 parents: HashMap<usize, usize>,
30 cursor_regions: Vec<CursorRegion>,
31 mouse_regions: Vec<(MouseRegion, usize)>,
32 font_cache: Arc<FontCache>,
33 text_layout_cache: TextLayoutCache,
34 asset_cache: Arc<AssetCache>,
35 last_mouse_moved_event: Option<Event>,
36 hovered_region_ids: HashSet<MouseRegionId>,
37 clicked_region: Option<MouseRegion>,
38 right_clicked_region: Option<MouseRegion>,
39 prev_drag_position: Option<Vector2F>,
40 titlebar_height: f32,
41}
42
43impl Presenter {
44 pub fn new(
45 window_id: usize,
46 titlebar_height: f32,
47 font_cache: Arc<FontCache>,
48 text_layout_cache: TextLayoutCache,
49 asset_cache: Arc<AssetCache>,
50 cx: &mut MutableAppContext,
51 ) -> Self {
52 Self {
53 window_id,
54 rendered_views: cx.render_views(window_id, titlebar_height),
55 parents: HashMap::new(),
56 cursor_regions: Default::default(),
57 mouse_regions: Default::default(),
58 font_cache,
59 text_layout_cache,
60 asset_cache,
61 last_mouse_moved_event: None,
62 hovered_region_ids: Default::default(),
63 clicked_region: None,
64 right_clicked_region: None,
65 prev_drag_position: None,
66 titlebar_height,
67 }
68 }
69
70 pub fn dispatch_path(&self, app: &AppContext) -> Vec<usize> {
71 let mut path = Vec::new();
72 if let Some(view_id) = app.focused_view_id(self.window_id) {
73 self.compute_dispatch_path_from(view_id, &mut path)
74 }
75 path
76 }
77
78 pub(crate) fn compute_dispatch_path_from(&self, mut view_id: usize, path: &mut Vec<usize>) {
79 path.push(view_id);
80 while let Some(parent_id) = self.parents.get(&view_id).copied() {
81 path.push(parent_id);
82 view_id = parent_id;
83 }
84 path.reverse();
85 }
86
87 pub fn invalidate(
88 &mut self,
89 invalidation: &mut WindowInvalidation,
90 cx: &mut MutableAppContext,
91 ) {
92 cx.start_frame();
93 for view_id in &invalidation.removed {
94 invalidation.updated.remove(&view_id);
95 self.rendered_views.remove(&view_id);
96 self.parents.remove(&view_id);
97 }
98 for view_id in &invalidation.updated {
99 self.rendered_views.insert(
100 *view_id,
101 cx.render_view(RenderParams {
102 window_id: self.window_id,
103 view_id: *view_id,
104 titlebar_height: self.titlebar_height,
105 hovered_region_ids: self.hovered_region_ids.clone(),
106 clicked_region_id: self.clicked_region.as_ref().and_then(MouseRegion::id),
107 right_clicked_region_id: self
108 .right_clicked_region
109 .as_ref()
110 .and_then(MouseRegion::id),
111 refreshing: false,
112 })
113 .unwrap(),
114 );
115 }
116 }
117
118 pub fn refresh(&mut self, invalidation: &mut WindowInvalidation, cx: &mut MutableAppContext) {
119 self.invalidate(invalidation, cx);
120 for (view_id, view) in &mut self.rendered_views {
121 if !invalidation.updated.contains(view_id) {
122 *view = cx
123 .render_view(RenderParams {
124 window_id: self.window_id,
125 view_id: *view_id,
126 titlebar_height: self.titlebar_height,
127 hovered_region_ids: self.hovered_region_ids.clone(),
128 clicked_region_id: self.clicked_region.as_ref().and_then(MouseRegion::id),
129 right_clicked_region_id: self
130 .right_clicked_region
131 .as_ref()
132 .and_then(MouseRegion::id),
133 refreshing: true,
134 })
135 .unwrap();
136 }
137 }
138 }
139
140 pub fn build_scene(
141 &mut self,
142 window_size: Vector2F,
143 scale_factor: f32,
144 refreshing: bool,
145 cx: &mut MutableAppContext,
146 ) -> Scene {
147 let mut scene = Scene::new(scale_factor);
148
149 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
150 self.layout(window_size, refreshing, cx);
151 let mut paint_cx = self.build_paint_context(&mut scene, window_size, cx);
152 paint_cx.paint(
153 root_view_id,
154 Vector2F::zero(),
155 RectF::new(Vector2F::zero(), window_size),
156 );
157 self.text_layout_cache.finish_frame();
158 self.cursor_regions = scene.cursor_regions();
159 self.mouse_regions = scene.mouse_regions();
160
161 if cx.window_is_active(self.window_id) {
162 if let Some(event) = self.last_mouse_moved_event.clone() {
163 let mut invalidated_views = Vec::new();
164 self.handle_hover_events(&event, &mut invalidated_views, cx);
165
166 for view_id in invalidated_views {
167 cx.notify_view(self.window_id, view_id);
168 }
169 }
170 }
171 } else {
172 log::error!("could not find root_view_id for window {}", self.window_id);
173 }
174
175 scene
176 }
177
178 fn layout(&mut self, window_size: Vector2F, refreshing: bool, cx: &mut MutableAppContext) {
179 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
180 self.build_layout_context(window_size, refreshing, cx)
181 .layout(root_view_id, SizeConstraint::strict(window_size));
182 }
183 }
184
185 pub fn build_layout_context<'a>(
186 &'a mut self,
187 window_size: Vector2F,
188 refreshing: bool,
189 cx: &'a mut MutableAppContext,
190 ) -> LayoutContext<'a> {
191 LayoutContext {
192 window_id: self.window_id,
193 rendered_views: &mut self.rendered_views,
194 parents: &mut self.parents,
195 font_cache: &self.font_cache,
196 font_system: cx.platform().fonts(),
197 text_layout_cache: &self.text_layout_cache,
198 asset_cache: &self.asset_cache,
199 view_stack: Vec::new(),
200 refreshing,
201 hovered_region_ids: self.hovered_region_ids.clone(),
202 clicked_region_id: self.clicked_region.as_ref().and_then(MouseRegion::id),
203 right_clicked_region_id: self.right_clicked_region.as_ref().and_then(MouseRegion::id),
204 titlebar_height: self.titlebar_height,
205 window_size,
206 app: cx,
207 }
208 }
209
210 pub fn build_paint_context<'a>(
211 &'a mut self,
212 scene: &'a mut Scene,
213 window_size: Vector2F,
214 cx: &'a mut MutableAppContext,
215 ) -> PaintContext {
216 PaintContext {
217 scene,
218 window_size,
219 font_cache: &self.font_cache,
220 text_layout_cache: &self.text_layout_cache,
221 rendered_views: &mut self.rendered_views,
222 view_stack: Vec::new(),
223 app: cx,
224 }
225 }
226
227 pub fn rect_for_text_range(&self, range_utf16: Range<usize>, cx: &AppContext) -> Option<RectF> {
228 cx.focused_view_id(self.window_id).and_then(|view_id| {
229 let cx = MeasurementContext {
230 app: cx,
231 rendered_views: &self.rendered_views,
232 window_id: self.window_id,
233 };
234 cx.rect_for_text_range(view_id, range_utf16)
235 })
236 }
237
238 pub fn dispatch_event(&mut self, event: Event, cx: &mut MutableAppContext) -> bool {
239 if let Some(root_view_id) = cx.root_view_id(self.window_id) {
240 let mut invalidated_views = Vec::new();
241 let mut mouse_down_out_handlers = Vec::new();
242 let mut mouse_down_region = None;
243 let mut clicked_region = None;
244 let mut dragged_region = None;
245
246 match &event {
247 Event::MouseDown(
248 e @ MouseButtonEvent {
249 position, button, ..
250 },
251 ) => {
252 let mut hit = false;
253 for (region, _) in self.mouse_regions.iter().rev() {
254 if region.bounds.contains_point(*position) {
255 if !hit {
256 hit = true;
257 invalidated_views.push(region.view_id);
258 mouse_down_region =
259 Some((region.clone(), MouseRegionEvent::Down(e.clone())));
260 self.clicked_region = Some(region.clone());
261 self.prev_drag_position = Some(*position);
262 }
263 } else if let Some(handler) = region
264 .handlers
265 .get(&(MouseRegionEvent::down_out_disc(), Some(*button)))
266 {
267 mouse_down_out_handlers.push((
268 handler,
269 region.view_id,
270 MouseRegionEvent::DownOut(e.clone()),
271 ));
272 }
273 }
274 }
275 Event::MouseUp(e @ MouseButtonEvent { position, .. }) => {
276 self.prev_drag_position.take();
277 if let Some(region) = self.clicked_region.take() {
278 invalidated_views.push(region.view_id);
279 if region.bounds.contains_point(*position) {
280 clicked_region = Some((region, MouseRegionEvent::Click(e.clone())));
281 }
282 }
283 }
284 Event::MouseMoved(e @ MouseMovedEvent { position, .. }) => {
285 if let Some((clicked_region, prev_drag_position)) = self
286 .clicked_region
287 .as_ref()
288 .zip(self.prev_drag_position.as_mut())
289 {
290 dragged_region = Some((
291 clicked_region.clone(),
292 MouseRegionEvent::Drag(*prev_drag_position, e.clone()),
293 ));
294 *prev_drag_position = *position;
295 }
296
297 self.last_mouse_moved_event = Some(event.clone());
298 }
299 _ => {}
300 }
301
302 let (mut handled, mut event_cx) =
303 self.handle_hover_events(&event, &mut invalidated_views, cx);
304
305 for (handler, view_id, region_event) in mouse_down_out_handlers {
306 event_cx.with_current_view(view_id, |event_cx| handler(region_event, event_cx))
307 }
308
309 if let Some((mouse_down_region, region_event)) = mouse_down_region {
310 handled = true;
311 if let Some(mouse_down_callback) =
312 mouse_down_region.handlers.get(®ion_event.handler_key())
313 {
314 event_cx.with_current_view(mouse_down_region.view_id, |event_cx| {
315 mouse_down_callback(region_event, event_cx);
316 })
317 }
318 }
319
320 if let Some((clicked_region, region_event)) = clicked_region {
321 handled = true;
322 if let Some(click_callback) =
323 clicked_region.handlers.get(®ion_event.handler_key())
324 {
325 event_cx.with_current_view(clicked_region.view_id, |event_cx| {
326 click_callback(region_event, event_cx);
327 })
328 }
329 }
330
331 if let Some((dragged_region, region_event)) = dragged_region {
332 handled = true;
333 if let Some(drag_callback) =
334 dragged_region.handlers.get(®ion_event.handler_key())
335 {
336 event_cx.with_current_view(dragged_region.view_id, |event_cx| {
337 drag_callback(region_event, event_cx);
338 })
339 }
340 }
341
342 if !handled {
343 handled = event_cx.dispatch_event(root_view_id, &event);
344 }
345
346 invalidated_views.extend(event_cx.invalidated_views);
347 let dispatch_directives = event_cx.dispatched_actions;
348
349 for view_id in invalidated_views {
350 cx.notify_view(self.window_id, view_id);
351 }
352
353 let mut dispatch_path = Vec::new();
354 for directive in dispatch_directives {
355 dispatch_path.clear();
356 if let Some(view_id) = directive.dispatcher_view_id {
357 self.compute_dispatch_path_from(view_id, &mut dispatch_path);
358 }
359 cx.dispatch_action_any(self.window_id, &dispatch_path, directive.action.as_ref());
360 }
361
362 handled
363 } else {
364 false
365 }
366 }
367
368 fn handle_hover_events<'a>(
369 &'a mut self,
370 event: &Event,
371 invalidated_views: &mut Vec<usize>,
372 cx: &'a mut MutableAppContext,
373 ) -> (bool, EventContext<'a>) {
374 let mut hover_regions = Vec::new();
375 // let mut unhovered_regions = Vec::new();
376 // let mut hovered_regions = Vec::new();
377
378 if let Event::MouseMoved(
379 e @ MouseMovedEvent {
380 position,
381 pressed_button,
382 ..
383 },
384 ) = event
385 {
386 if let None = pressed_button {
387 let mut style_to_assign = CursorStyle::Arrow;
388 for region in self.cursor_regions.iter().rev() {
389 if region.bounds.contains_point(*position) {
390 style_to_assign = region.style;
391 break;
392 }
393 }
394 cx.platform().set_cursor_style(style_to_assign);
395
396 let mut hover_depth = None;
397 for (region, depth) in self.mouse_regions.iter().rev() {
398 if region.bounds.contains_point(*position)
399 && hover_depth.map_or(true, |hover_depth| hover_depth == *depth)
400 {
401 hover_depth = Some(*depth);
402 if let Some(region_id) = region.id() {
403 if !self.hovered_region_ids.contains(®ion_id) {
404 invalidated_views.push(region.view_id);
405 hover_regions.push((
406 region.clone(),
407 MouseRegionEvent::Hover(true, e.clone()),
408 ));
409 self.hovered_region_ids.insert(region_id);
410 }
411 }
412 } else {
413 if let Some(region_id) = region.id() {
414 if self.hovered_region_ids.contains(®ion_id) {
415 invalidated_views.push(region.view_id);
416 hover_regions.push((
417 region.clone(),
418 MouseRegionEvent::Hover(false, e.clone()),
419 ));
420 self.hovered_region_ids.remove(®ion_id);
421 }
422 }
423 }
424 }
425 }
426 }
427
428 let mut event_cx = self.build_event_context(cx);
429 let mut handled = false;
430
431 for (hover_region, region_event) in hover_regions {
432 handled = true;
433 if let Some(hover_callback) = hover_region.handlers.get(®ion_event.handler_key()) {
434 event_cx.with_current_view(hover_region.view_id, |event_cx| {
435 hover_callback(region_event, event_cx);
436 })
437 }
438 }
439
440 (handled, event_cx)
441 }
442
443 pub fn build_event_context<'a>(
444 &'a mut self,
445 cx: &'a mut MutableAppContext,
446 ) -> EventContext<'a> {
447 EventContext {
448 rendered_views: &mut self.rendered_views,
449 dispatched_actions: Default::default(),
450 font_cache: &self.font_cache,
451 text_layout_cache: &self.text_layout_cache,
452 view_stack: Default::default(),
453 invalidated_views: Default::default(),
454 notify_count: 0,
455 window_id: self.window_id,
456 app: cx,
457 }
458 }
459
460 pub fn debug_elements(&self, cx: &AppContext) -> Option<json::Value> {
461 let view = cx.root_view(self.window_id)?;
462 Some(json!({
463 "root_view": view.debug_json(cx),
464 "root_element": self.rendered_views.get(&view.id())
465 .map(|root_element| {
466 root_element.debug(&DebugContext {
467 rendered_views: &self.rendered_views,
468 font_cache: &self.font_cache,
469 app: cx,
470 })
471 })
472 }))
473 }
474}
475
476pub struct DispatchDirective {
477 pub dispatcher_view_id: Option<usize>,
478 pub action: Box<dyn Action>,
479}
480
481pub struct LayoutContext<'a> {
482 window_id: usize,
483 rendered_views: &'a mut HashMap<usize, ElementBox>,
484 parents: &'a mut HashMap<usize, usize>,
485 view_stack: Vec<usize>,
486 pub font_cache: &'a Arc<FontCache>,
487 pub font_system: Arc<dyn FontSystem>,
488 pub text_layout_cache: &'a TextLayoutCache,
489 pub asset_cache: &'a AssetCache,
490 pub app: &'a mut MutableAppContext,
491 pub refreshing: bool,
492 pub window_size: Vector2F,
493 titlebar_height: f32,
494 hovered_region_ids: HashSet<MouseRegionId>,
495 clicked_region_id: Option<MouseRegionId>,
496 right_clicked_region_id: Option<MouseRegionId>,
497}
498
499impl<'a> LayoutContext<'a> {
500 pub(crate) fn keystrokes_for_action(
501 &self,
502 action: &dyn Action,
503 ) -> Option<SmallVec<[Keystroke; 2]>> {
504 self.app
505 .keystrokes_for_action(self.window_id, &self.view_stack, action)
506 }
507
508 fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
509 if let Some(parent_id) = self.view_stack.last() {
510 self.parents.insert(view_id, *parent_id);
511 }
512 self.view_stack.push(view_id);
513 let mut rendered_view = self.rendered_views.remove(&view_id).unwrap();
514 let size = rendered_view.layout(constraint, self);
515 self.rendered_views.insert(view_id, rendered_view);
516 self.view_stack.pop();
517 size
518 }
519
520 pub fn render<F, V, T>(&mut self, handle: &ViewHandle<V>, f: F) -> T
521 where
522 F: FnOnce(&mut V, &mut RenderContext<V>) -> T,
523 V: View,
524 {
525 handle.update(self.app, |view, cx| {
526 let mut render_cx = RenderContext {
527 app: cx,
528 window_id: handle.window_id(),
529 view_id: handle.id(),
530 view_type: PhantomData,
531 titlebar_height: self.titlebar_height,
532 hovered_region_ids: self.hovered_region_ids.clone(),
533 clicked_region_id: self.clicked_region_id,
534 right_clicked_region_id: self.right_clicked_region_id,
535 refreshing: self.refreshing,
536 };
537 f(view, &mut render_cx)
538 })
539 }
540}
541
542impl<'a> Deref for LayoutContext<'a> {
543 type Target = MutableAppContext;
544
545 fn deref(&self) -> &Self::Target {
546 self.app
547 }
548}
549
550impl<'a> DerefMut for LayoutContext<'a> {
551 fn deref_mut(&mut self) -> &mut Self::Target {
552 self.app
553 }
554}
555
556impl<'a> ReadView for LayoutContext<'a> {
557 fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
558 self.app.read_view(handle)
559 }
560}
561
562impl<'a> ReadModel for LayoutContext<'a> {
563 fn read_model<T: Entity>(&self, handle: &ModelHandle<T>) -> &T {
564 self.app.read_model(handle)
565 }
566}
567
568impl<'a> UpgradeModelHandle for LayoutContext<'a> {
569 fn upgrade_model_handle<T: Entity>(
570 &self,
571 handle: &WeakModelHandle<T>,
572 ) -> Option<ModelHandle<T>> {
573 self.app.upgrade_model_handle(handle)
574 }
575
576 fn model_handle_is_upgradable<T: Entity>(&self, handle: &WeakModelHandle<T>) -> bool {
577 self.app.model_handle_is_upgradable(handle)
578 }
579
580 fn upgrade_any_model_handle(&self, handle: &AnyWeakModelHandle) -> Option<AnyModelHandle> {
581 self.app.upgrade_any_model_handle(handle)
582 }
583}
584
585impl<'a> UpgradeViewHandle for LayoutContext<'a> {
586 fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
587 self.app.upgrade_view_handle(handle)
588 }
589
590 fn upgrade_any_view_handle(&self, handle: &crate::AnyWeakViewHandle) -> Option<AnyViewHandle> {
591 self.app.upgrade_any_view_handle(handle)
592 }
593}
594
595pub struct PaintContext<'a> {
596 rendered_views: &'a mut HashMap<usize, ElementBox>,
597 view_stack: Vec<usize>,
598 pub window_size: Vector2F,
599 pub scene: &'a mut Scene,
600 pub font_cache: &'a FontCache,
601 pub text_layout_cache: &'a TextLayoutCache,
602 pub app: &'a AppContext,
603}
604
605impl<'a> PaintContext<'a> {
606 fn paint(&mut self, view_id: usize, origin: Vector2F, visible_bounds: RectF) {
607 if let Some(mut tree) = self.rendered_views.remove(&view_id) {
608 self.view_stack.push(view_id);
609 tree.paint(origin, visible_bounds, self);
610 self.rendered_views.insert(view_id, tree);
611 self.view_stack.pop();
612 }
613 }
614
615 #[inline]
616 pub fn paint_layer<F>(&mut self, clip_bounds: Option<RectF>, f: F)
617 where
618 F: FnOnce(&mut Self) -> (),
619 {
620 self.scene.push_layer(clip_bounds);
621 f(self);
622 self.scene.pop_layer();
623 }
624
625 pub fn current_view_id(&self) -> usize {
626 *self.view_stack.last().unwrap()
627 }
628}
629
630impl<'a> Deref for PaintContext<'a> {
631 type Target = AppContext;
632
633 fn deref(&self) -> &Self::Target {
634 self.app
635 }
636}
637
638pub struct EventContext<'a> {
639 rendered_views: &'a mut HashMap<usize, ElementBox>,
640 dispatched_actions: Vec<DispatchDirective>,
641 pub font_cache: &'a FontCache,
642 pub text_layout_cache: &'a TextLayoutCache,
643 pub app: &'a mut MutableAppContext,
644 pub window_id: usize,
645 pub notify_count: usize,
646 view_stack: Vec<usize>,
647 invalidated_views: HashSet<usize>,
648}
649
650impl<'a> EventContext<'a> {
651 fn dispatch_event(&mut self, view_id: usize, event: &Event) -> bool {
652 if let Some(mut element) = self.rendered_views.remove(&view_id) {
653 let result =
654 self.with_current_view(view_id, |this| element.dispatch_event(event, this));
655 self.rendered_views.insert(view_id, element);
656 result
657 } else {
658 false
659 }
660 }
661
662 fn with_current_view<F, T>(&mut self, view_id: usize, f: F) -> T
663 where
664 F: FnOnce(&mut Self) -> T,
665 {
666 self.view_stack.push(view_id);
667 let result = f(self);
668 self.view_stack.pop();
669 result
670 }
671
672 pub fn window_id(&self) -> usize {
673 self.window_id
674 }
675
676 pub fn view_id(&self) -> Option<usize> {
677 self.view_stack.last().copied()
678 }
679
680 pub fn is_parent_view_focused(&self) -> bool {
681 if let Some(parent_view_id) = self.view_stack.last() {
682 self.app.focused_view_id(self.window_id) == Some(*parent_view_id)
683 } else {
684 false
685 }
686 }
687
688 pub fn focus_parent_view(&mut self) {
689 if let Some(parent_view_id) = self.view_stack.last() {
690 self.app.focus(self.window_id, Some(*parent_view_id))
691 }
692 }
693
694 pub fn dispatch_any_action(&mut self, action: Box<dyn Action>) {
695 self.dispatched_actions.push(DispatchDirective {
696 dispatcher_view_id: self.view_stack.last().copied(),
697 action,
698 });
699 }
700
701 pub fn dispatch_action<A: Action>(&mut self, action: A) {
702 self.dispatch_any_action(Box::new(action));
703 }
704
705 pub fn notify(&mut self) {
706 self.notify_count += 1;
707 if let Some(view_id) = self.view_stack.last() {
708 self.invalidated_views.insert(*view_id);
709 }
710 }
711
712 pub fn notify_count(&self) -> usize {
713 self.notify_count
714 }
715}
716
717impl<'a> Deref for EventContext<'a> {
718 type Target = MutableAppContext;
719
720 fn deref(&self) -> &Self::Target {
721 self.app
722 }
723}
724
725impl<'a> DerefMut for EventContext<'a> {
726 fn deref_mut(&mut self) -> &mut Self::Target {
727 self.app
728 }
729}
730
731pub struct MeasurementContext<'a> {
732 app: &'a AppContext,
733 rendered_views: &'a HashMap<usize, ElementBox>,
734 pub window_id: usize,
735}
736
737impl<'a> Deref for MeasurementContext<'a> {
738 type Target = AppContext;
739
740 fn deref(&self) -> &Self::Target {
741 self.app
742 }
743}
744
745impl<'a> MeasurementContext<'a> {
746 fn rect_for_text_range(&self, view_id: usize, range_utf16: Range<usize>) -> Option<RectF> {
747 let element = self.rendered_views.get(&view_id)?;
748 element.rect_for_text_range(range_utf16, self)
749 }
750}
751
752pub struct DebugContext<'a> {
753 rendered_views: &'a HashMap<usize, ElementBox>,
754 pub font_cache: &'a FontCache,
755 pub app: &'a AppContext,
756}
757
758#[derive(Clone, Copy, Debug, Eq, PartialEq)]
759pub enum Axis {
760 Horizontal,
761 Vertical,
762}
763
764impl Axis {
765 pub fn invert(self) -> Self {
766 match self {
767 Self::Horizontal => Self::Vertical,
768 Self::Vertical => Self::Horizontal,
769 }
770 }
771}
772
773impl ToJson for Axis {
774 fn to_json(&self) -> serde_json::Value {
775 match self {
776 Axis::Horizontal => json!("horizontal"),
777 Axis::Vertical => json!("vertical"),
778 }
779 }
780}
781
782pub trait Vector2FExt {
783 fn along(self, axis: Axis) -> f32;
784}
785
786impl Vector2FExt for Vector2F {
787 fn along(self, axis: Axis) -> f32 {
788 match axis {
789 Axis::Horizontal => self.x(),
790 Axis::Vertical => self.y(),
791 }
792 }
793}
794
795#[derive(Copy, Clone, Debug)]
796pub struct SizeConstraint {
797 pub min: Vector2F,
798 pub max: Vector2F,
799}
800
801impl SizeConstraint {
802 pub fn new(min: Vector2F, max: Vector2F) -> Self {
803 Self { min, max }
804 }
805
806 pub fn strict(size: Vector2F) -> Self {
807 Self {
808 min: size,
809 max: size,
810 }
811 }
812
813 pub fn strict_along(axis: Axis, max: f32) -> Self {
814 match axis {
815 Axis::Horizontal => Self {
816 min: vec2f(max, 0.0),
817 max: vec2f(max, f32::INFINITY),
818 },
819 Axis::Vertical => Self {
820 min: vec2f(0.0, max),
821 max: vec2f(f32::INFINITY, max),
822 },
823 }
824 }
825
826 pub fn max_along(&self, axis: Axis) -> f32 {
827 match axis {
828 Axis::Horizontal => self.max.x(),
829 Axis::Vertical => self.max.y(),
830 }
831 }
832
833 pub fn min_along(&self, axis: Axis) -> f32 {
834 match axis {
835 Axis::Horizontal => self.min.x(),
836 Axis::Vertical => self.min.y(),
837 }
838 }
839
840 pub fn constrain(&self, size: Vector2F) -> Vector2F {
841 vec2f(
842 size.x().min(self.max.x()).max(self.min.x()),
843 size.y().min(self.max.y()).max(self.min.y()),
844 )
845 }
846}
847
848impl Default for SizeConstraint {
849 fn default() -> Self {
850 SizeConstraint {
851 min: Vector2F::zero(),
852 max: Vector2F::splat(f32::INFINITY),
853 }
854 }
855}
856
857impl ToJson for SizeConstraint {
858 fn to_json(&self) -> serde_json::Value {
859 json!({
860 "min": self.min.to_json(),
861 "max": self.max.to_json(),
862 })
863 }
864}
865
866pub struct ChildView {
867 view: AnyViewHandle,
868}
869
870impl ChildView {
871 pub fn new(view: impl Into<AnyViewHandle>) -> Self {
872 Self { view: view.into() }
873 }
874}
875
876impl Element for ChildView {
877 type LayoutState = ();
878 type PaintState = ();
879
880 fn layout(
881 &mut self,
882 constraint: SizeConstraint,
883 cx: &mut LayoutContext,
884 ) -> (Vector2F, Self::LayoutState) {
885 let size = cx.layout(self.view.id(), constraint);
886 (size, ())
887 }
888
889 fn paint(
890 &mut self,
891 bounds: RectF,
892 visible_bounds: RectF,
893 _: &mut Self::LayoutState,
894 cx: &mut PaintContext,
895 ) -> Self::PaintState {
896 cx.paint(self.view.id(), bounds.origin(), visible_bounds);
897 }
898
899 fn dispatch_event(
900 &mut self,
901 event: &Event,
902 _: RectF,
903 _: RectF,
904 _: &mut Self::LayoutState,
905 _: &mut Self::PaintState,
906 cx: &mut EventContext,
907 ) -> bool {
908 cx.dispatch_event(self.view.id(), event)
909 }
910
911 fn rect_for_text_range(
912 &self,
913 range_utf16: Range<usize>,
914 _: RectF,
915 _: RectF,
916 _: &Self::LayoutState,
917 _: &Self::PaintState,
918 cx: &MeasurementContext,
919 ) -> Option<RectF> {
920 cx.rect_for_text_range(self.view.id(), range_utf16)
921 }
922
923 fn debug(
924 &self,
925 bounds: RectF,
926 _: &Self::LayoutState,
927 _: &Self::PaintState,
928 cx: &DebugContext,
929 ) -> serde_json::Value {
930 json!({
931 "type": "ChildView",
932 "view_id": self.view.id(),
933 "bounds": bounds.to_json(),
934 "view": self.view.debug_json(cx.app),
935 "child": if let Some(view) = cx.rendered_views.get(&self.view.id()) {
936 view.debug(cx)
937 } else {
938 json!(null)
939 }
940 })
941 }
942}