scene.rs

  1mod mouse_event;
  2mod mouse_region;
  3mod region;
  4
  5#[cfg(debug_assertions)]
  6use collections::HashSet;
  7use derive_more::Mul;
  8use schemars::JsonSchema;
  9use serde::Deserialize;
 10use serde_derive::Serialize;
 11use std::{
 12    any::{Any, TypeId},
 13    borrow::Cow,
 14    rc::Rc,
 15    sync::Arc,
 16};
 17
 18use crate::{
 19    color::Color,
 20    fonts::{FontId, GlyphId},
 21    geometry::{rect::RectF, vector::Vector2F},
 22    platform::{current::Surface, CursorStyle},
 23    ImageData, WindowContext,
 24};
 25pub use mouse_event::*;
 26pub use mouse_region::*;
 27
 28pub struct SceneBuilder {
 29    stacking_contexts: Vec<StackingContext>,
 30    active_stacking_context_stack: Vec<usize>,
 31    /// Used by the gpui2 crate.
 32    pub event_handlers: Vec<EventHandler>,
 33    #[cfg(debug_assertions)]
 34    mouse_region_ids: HashSet<MouseRegionId>,
 35}
 36
 37pub struct Scene {
 38    scale_factor: f32,
 39    stacking_contexts: Vec<StackingContext>,
 40    event_handlers: Vec<EventHandler>,
 41}
 42
 43struct StackingContext {
 44    layers: Vec<Layer>,
 45    active_layer_stack: Vec<usize>,
 46    z_index: usize,
 47}
 48
 49#[derive(Default)]
 50pub struct Layer {
 51    clip_bounds: Option<RectF>,
 52    quads: Vec<Quad>,
 53    underlines: Vec<Underline>,
 54    images: Vec<Image>,
 55    surfaces: Vec<Surface>,
 56    shadows: Vec<Shadow>,
 57    glyphs: Vec<Glyph>,
 58    image_glyphs: Vec<ImageGlyph>,
 59    icons: Vec<Icon>,
 60    paths: Vec<Path>,
 61    cursor_regions: Vec<CursorRegion>,
 62    mouse_regions: Vec<MouseRegion>,
 63}
 64
 65#[derive(Copy, Clone)]
 66pub struct CursorRegion {
 67    pub bounds: RectF,
 68    pub style: CursorStyle,
 69}
 70
 71#[derive(Default, Debug)]
 72pub struct Quad {
 73    pub bounds: RectF,
 74    pub background: Option<Color>,
 75    pub border: Border,
 76    pub corner_radii: CornerRadii,
 77}
 78
 79#[derive(Default, Debug, Mul, Clone, Copy, Serialize, JsonSchema)]
 80pub struct CornerRadii {
 81    pub top_left: f32,
 82    pub top_right: f32,
 83    pub bottom_right: f32,
 84    pub bottom_left: f32,
 85}
 86
 87impl<'de> Deserialize<'de> for CornerRadii {
 88    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
 89    where
 90        D: serde::Deserializer<'de>,
 91    {
 92        #[derive(Deserialize)]
 93        pub struct CornerRadiiHelper {
 94            pub top_left: Option<f32>,
 95            pub top_right: Option<f32>,
 96            pub bottom_right: Option<f32>,
 97            pub bottom_left: Option<f32>,
 98        }
 99
100        #[derive(Deserialize)]
101        #[serde(untagged)]
102        enum RadiusOrRadii {
103            Radius(f32),
104            Radii(CornerRadiiHelper),
105        }
106
107        let json = RadiusOrRadii::deserialize(deserializer)?;
108
109        let result = match json {
110            RadiusOrRadii::Radius(radius) => CornerRadii::from(radius),
111            RadiusOrRadii::Radii(CornerRadiiHelper {
112                top_left,
113                top_right,
114                bottom_right,
115                bottom_left,
116            }) => CornerRadii {
117                top_left: top_left.unwrap_or(0.0),
118                top_right: top_right.unwrap_or(0.0),
119                bottom_right: bottom_right.unwrap_or(0.0),
120                bottom_left: bottom_left.unwrap_or(0.0),
121            },
122        };
123
124        Ok(result)
125    }
126}
127
128impl From<f32> for CornerRadii {
129    fn from(radius: f32) -> Self {
130        Self {
131            top_left: radius,
132            top_right: radius,
133            bottom_right: radius,
134            bottom_left: radius,
135        }
136    }
137}
138
139#[derive(Debug)]
140pub struct Shadow {
141    pub bounds: RectF,
142    pub corner_radii: CornerRadii,
143    pub sigma: f32,
144    pub color: Color,
145}
146
147#[derive(Debug, Clone, Copy)]
148pub struct Glyph {
149    pub font_id: FontId,
150    pub font_size: f32,
151    pub id: GlyphId,
152    pub origin: Vector2F,
153    pub color: Color,
154}
155
156#[derive(Debug)]
157pub struct ImageGlyph {
158    pub font_id: FontId,
159    pub font_size: f32,
160    pub id: GlyphId,
161    pub origin: Vector2F,
162}
163
164pub struct Icon {
165    pub bounds: RectF,
166    pub svg: usvg::Tree,
167    pub path: Cow<'static, str>,
168    pub color: Color,
169}
170
171#[derive(Clone, Copy, Default, Debug)]
172pub struct Border {
173    pub color: Color,
174    pub top: f32,
175    pub right: f32,
176    pub bottom: f32,
177    pub left: f32,
178}
179
180#[derive(Clone, Copy, Default, Debug)]
181pub struct Underline {
182    pub origin: Vector2F,
183    pub width: f32,
184    pub thickness: f32,
185    pub color: Color,
186    pub squiggly: bool,
187}
188
189#[derive(Debug)]
190pub struct Path {
191    pub bounds: RectF,
192    pub color: Color,
193    pub vertices: Vec<PathVertex>,
194}
195
196#[derive(Debug)]
197pub struct PathVertex {
198    pub xy_position: Vector2F,
199    pub st_position: Vector2F,
200}
201
202pub struct Image {
203    pub bounds: RectF,
204    pub border: Border,
205    pub corner_radii: CornerRadii,
206    pub grayscale: bool,
207    pub data: Arc<ImageData>,
208}
209
210impl Scene {
211    pub fn scale_factor(&self) -> f32 {
212        self.scale_factor
213    }
214
215    pub fn layers(&self) -> impl Iterator<Item = &Layer> {
216        self.stacking_contexts.iter().flat_map(|s| &s.layers)
217    }
218
219    pub fn cursor_regions(&self) -> Vec<CursorRegion> {
220        self.layers()
221            .flat_map(|layer| &layer.cursor_regions)
222            .copied()
223            .collect()
224    }
225
226    pub fn mouse_regions(&self) -> Vec<(MouseRegion, usize)> {
227        self.stacking_contexts
228            .iter()
229            .flat_map(|context| {
230                context
231                    .layers
232                    .iter()
233                    .flat_map(|layer| &layer.mouse_regions)
234                    .map(|region| (region.clone(), context.z_index))
235            })
236            .collect()
237    }
238
239    pub fn take_event_handlers(&mut self) -> Vec<EventHandler> {
240        self.event_handlers
241            .sort_by(|a, b| a.order.cmp(&b.order).reverse());
242        std::mem::take(&mut self.event_handlers)
243    }
244}
245
246impl SceneBuilder {
247    pub fn new() -> Self {
248        let mut this = SceneBuilder {
249            stacking_contexts: Vec::new(),
250            active_stacking_context_stack: Vec::new(),
251            #[cfg(debug_assertions)]
252            mouse_region_ids: HashSet::default(),
253            event_handlers: Vec::new(),
254        };
255        this.clear();
256        this
257    }
258
259    pub fn clear(&mut self) {
260        self.stacking_contexts.clear();
261        self.stacking_contexts.push(StackingContext::new(None, 0));
262        self.active_stacking_context_stack.clear();
263        self.active_stacking_context_stack.push(0);
264    }
265
266    pub fn build(&mut self, scale_factor: f32) -> Scene {
267        let mut stacking_contexts = std::mem::take(&mut self.stacking_contexts);
268        stacking_contexts.sort_by_key(|context| context.z_index);
269        let event_handlers = std::mem::take(&mut self.event_handlers);
270        self.clear();
271
272        Scene {
273            scale_factor,
274            stacking_contexts,
275            event_handlers,
276        }
277    }
278
279    pub fn push_stacking_context(&mut self, clip_bounds: Option<RectF>, z_index: Option<usize>) {
280        let z_index = z_index.unwrap_or_else(|| self.active_stacking_context().z_index + 1);
281        self.active_stacking_context_stack
282            .push(self.stacking_contexts.len());
283        self.stacking_contexts
284            .push(StackingContext::new(clip_bounds, z_index))
285    }
286
287    pub fn pop_stacking_context(&mut self) {
288        self.active_stacking_context_stack.pop();
289        assert!(!self.active_stacking_context_stack.is_empty());
290    }
291
292    pub fn push_layer(&mut self, clip_bounds: Option<RectF>) {
293        self.active_stacking_context().push_layer(clip_bounds);
294    }
295
296    pub fn pop_layer(&mut self) {
297        self.active_stacking_context().pop_layer();
298    }
299
300    pub fn push_quad(&mut self, quad: Quad) {
301        self.active_layer().push_quad(quad)
302    }
303
304    pub fn push_cursor_region(&mut self, region: CursorRegion) {
305        if can_draw(region.bounds) {
306            self.active_layer().push_cursor_region(region);
307        }
308    }
309
310    pub fn push_mouse_region(&mut self, region: MouseRegion) {
311        if can_draw(region.bounds) {
312            // Ensure that Regions cannot be added to a scene with the same region id.
313            #[cfg(debug_assertions)]
314            let region_id;
315            #[cfg(debug_assertions)]
316            {
317                region_id = region.id();
318            }
319
320            if self.active_layer().push_mouse_region(region) {
321                #[cfg(debug_assertions)]
322                {
323                    if !self.mouse_region_ids.insert(region_id) {
324                        let tag_name = region_id.tag_type_name();
325                        panic!("Same MouseRegionId: {region_id:?} inserted multiple times to the same scene. \
326                            Will cause problems! Look for MouseRegion that uses Tag: {tag_name}");
327                    }
328                }
329            }
330        }
331    }
332
333    pub fn push_image(&mut self, image: Image) {
334        self.active_layer().push_image(image)
335    }
336
337    pub fn push_surface(&mut self, surface: Surface) {
338        self.active_layer().push_surface(surface)
339    }
340
341    pub fn push_underline(&mut self, underline: Underline) {
342        self.active_layer().push_underline(underline)
343    }
344
345    pub fn push_shadow(&mut self, shadow: Shadow) {
346        self.active_layer().push_shadow(shadow)
347    }
348
349    pub fn push_glyph(&mut self, glyph: Glyph) {
350        self.active_layer().push_glyph(glyph)
351    }
352
353    pub fn push_image_glyph(&mut self, image_glyph: ImageGlyph) {
354        self.active_layer().push_image_glyph(image_glyph)
355    }
356
357    pub fn push_icon(&mut self, icon: Icon) {
358        self.active_layer().push_icon(icon)
359    }
360
361    pub fn push_path(&mut self, path: Path) {
362        self.active_layer().push_path(path);
363    }
364
365    fn active_stacking_context(&mut self) -> &mut StackingContext {
366        let ix = *self.active_stacking_context_stack.last().unwrap();
367        &mut self.stacking_contexts[ix]
368    }
369
370    fn active_layer(&mut self) -> &mut Layer {
371        self.active_stacking_context().active_layer()
372    }
373}
374
375impl StackingContext {
376    fn new(clip_bounds: Option<RectF>, z_index: usize) -> Self {
377        Self {
378            layers: vec![Layer::new(clip_bounds)],
379            active_layer_stack: vec![0],
380            z_index,
381        }
382    }
383
384    fn active_layer(&mut self) -> &mut Layer {
385        &mut self.layers[*self.active_layer_stack.last().unwrap()]
386    }
387
388    fn push_layer(&mut self, clip_bounds: Option<RectF>) {
389        let parent_clip_bounds = self.active_layer().clip_bounds();
390        let clip_bounds = clip_bounds
391            .map(|clip_bounds| {
392                clip_bounds
393                    .intersection(parent_clip_bounds.unwrap_or(clip_bounds))
394                    .unwrap_or_else(|| {
395                        if !clip_bounds.is_empty() {
396                            log::warn!("specified clip bounds are disjoint from parent layer");
397                        }
398                        RectF::default()
399                    })
400            })
401            .or(parent_clip_bounds);
402
403        let ix = self.layers.len();
404        self.layers.push(Layer::new(clip_bounds));
405        self.active_layer_stack.push(ix);
406    }
407
408    fn pop_layer(&mut self) {
409        self.active_layer_stack.pop().unwrap();
410        assert!(!self.active_layer_stack.is_empty());
411    }
412}
413
414impl Layer {
415    pub fn new(clip_bounds: Option<RectF>) -> Self {
416        Self {
417            clip_bounds,
418            quads: Default::default(),
419            underlines: Default::default(),
420            images: Default::default(),
421            surfaces: Default::default(),
422            shadows: Default::default(),
423            image_glyphs: Default::default(),
424            glyphs: Default::default(),
425            icons: Default::default(),
426            paths: Default::default(),
427            cursor_regions: Default::default(),
428            mouse_regions: Default::default(),
429        }
430    }
431
432    pub fn clip_bounds(&self) -> Option<RectF> {
433        self.clip_bounds
434    }
435
436    fn push_quad(&mut self, quad: Quad) {
437        if can_draw(quad.bounds) {
438            self.quads.push(quad);
439        }
440    }
441
442    pub fn quads(&self) -> &[Quad] {
443        self.quads.as_slice()
444    }
445
446    fn push_cursor_region(&mut self, region: CursorRegion) {
447        if let Some(bounds) = region
448            .bounds
449            .intersection(self.clip_bounds.unwrap_or(region.bounds))
450        {
451            if can_draw(bounds) {
452                self.cursor_regions.push(region);
453            }
454        }
455    }
456
457    fn push_mouse_region(&mut self, region: MouseRegion) -> bool {
458        if let Some(bounds) = region
459            .bounds
460            .intersection(self.clip_bounds.unwrap_or(region.bounds))
461        {
462            if can_draw(bounds) {
463                self.mouse_regions.push(region);
464                return true;
465            }
466        }
467        false
468    }
469
470    fn push_underline(&mut self, underline: Underline) {
471        if underline.width > 0. {
472            self.underlines.push(underline);
473        }
474    }
475
476    pub fn underlines(&self) -> &[Underline] {
477        self.underlines.as_slice()
478    }
479
480    fn push_image(&mut self, image: Image) {
481        if can_draw(image.bounds) {
482            self.images.push(image);
483        }
484    }
485
486    pub fn images(&self) -> &[Image] {
487        self.images.as_slice()
488    }
489
490    fn push_surface(&mut self, surface: Surface) {
491        if can_draw(surface.bounds) {
492            self.surfaces.push(surface);
493        }
494    }
495
496    pub fn surfaces(&self) -> &[Surface] {
497        self.surfaces.as_slice()
498    }
499
500    fn push_shadow(&mut self, shadow: Shadow) {
501        if can_draw(shadow.bounds) {
502            self.shadows.push(shadow);
503        }
504    }
505
506    pub fn shadows(&self) -> &[Shadow] {
507        self.shadows.as_slice()
508    }
509
510    fn push_image_glyph(&mut self, glyph: ImageGlyph) {
511        self.image_glyphs.push(glyph);
512    }
513
514    pub fn image_glyphs(&self) -> &[ImageGlyph] {
515        self.image_glyphs.as_slice()
516    }
517
518    fn push_glyph(&mut self, glyph: Glyph) {
519        self.glyphs.push(glyph);
520    }
521
522    pub fn glyphs(&self) -> &[Glyph] {
523        self.glyphs.as_slice()
524    }
525
526    pub fn push_icon(&mut self, icon: Icon) {
527        if can_draw(icon.bounds) {
528            self.icons.push(icon);
529        }
530    }
531
532    pub fn icons(&self) -> &[Icon] {
533        self.icons.as_slice()
534    }
535
536    fn push_path(&mut self, path: Path) {
537        if can_draw(path.bounds) {
538            self.paths.push(path);
539        }
540    }
541
542    pub fn paths(&self) -> &[Path] {
543        self.paths.as_slice()
544    }
545}
546
547impl MouseRegion {
548    pub fn id(&self) -> MouseRegionId {
549        self.id
550    }
551}
552
553pub struct EventHandler {
554    pub order: u32,
555    // The &dyn Any parameter below expects an event.
556    pub handler: Rc<dyn Fn(&dyn Any, &mut WindowContext) -> bool>,
557    pub event_type: TypeId,
558}
559
560fn can_draw(bounds: RectF) -> bool {
561    let size = bounds.size();
562    size.x() > 0. && size.y() > 0.
563}