1use std::{iter, mem, ops::Range};
2
3use crate::{
4 black, phi, point, quad, rems, AbsoluteLength, Bounds, ContentMask, Corners, CornersRefinement,
5 CursorStyle, DefiniteLength, Edges, EdgesRefinement, ElementContext, Font, FontFeatures,
6 FontStyle, FontWeight, Hsla, Length, Pixels, Point, PointRefinement, Rgba, SharedString, Size,
7 SizeRefinement, Styled, TextRun,
8};
9use collections::HashSet;
10use refineable::{Cascade, Refineable};
11use smallvec::SmallVec;
12pub use taffy::style::{
13 AlignContent, AlignItems, AlignSelf, Display, FlexDirection, FlexWrap, JustifyContent,
14 Overflow, Position,
15};
16
17#[cfg(debug_assertions)]
18pub struct DebugBelow;
19
20pub type StyleCascade = Cascade<Style>;
21
22#[derive(Clone, Refineable, Debug)]
23#[refineable(Debug)]
24pub struct Style {
25 /// What layout strategy should be used?
26 pub display: Display,
27
28 /// Should the element be painted on screen?
29 pub visibility: Visibility,
30
31 // Overflow properties
32 /// How children overflowing their container should affect layout
33 #[refineable]
34 pub overflow: Point<Overflow>,
35 /// How much space (in points) should be reserved for the scrollbars of `Overflow::Scroll` and `Overflow::Auto` nodes.
36 pub scrollbar_width: f32,
37
38 // Position properties
39 /// What should the `position` value of this struct use as a base offset?
40 pub position: Position,
41 /// How should the position of this element be tweaked relative to the layout defined?
42 #[refineable]
43 pub inset: Edges<Length>,
44
45 // Size properties
46 /// Sets the initial size of the item
47 #[refineable]
48 pub size: Size<Length>,
49 /// Controls the minimum size of the item
50 #[refineable]
51 pub min_size: Size<Length>,
52 /// Controls the maximum size of the item
53 #[refineable]
54 pub max_size: Size<Length>,
55 /// Sets the preferred aspect ratio for the item. The ratio is calculated as width divided by height.
56 pub aspect_ratio: Option<f32>,
57
58 // Spacing Properties
59 /// How large should the margin be on each side?
60 #[refineable]
61 pub margin: Edges<Length>,
62 /// How large should the padding be on each side?
63 #[refineable]
64 pub padding: Edges<DefiniteLength>,
65 /// How large should the border be on each side?
66 #[refineable]
67 pub border_widths: Edges<AbsoluteLength>,
68
69 // Alignment properties
70 /// How this node's children aligned in the cross/block axis?
71 pub align_items: Option<AlignItems>,
72 /// How this node should be aligned in the cross/block axis. Falls back to the parents [`AlignItems`] if not set
73 pub align_self: Option<AlignSelf>,
74 /// How should content contained within this item be aligned in the cross/block axis
75 pub align_content: Option<AlignContent>,
76 /// How should contained within this item be aligned in the main/inline axis
77 pub justify_content: Option<JustifyContent>,
78 /// How large should the gaps between items in a flex container be?
79 #[refineable]
80 pub gap: Size<DefiniteLength>,
81
82 // Flexbox properties
83 /// Which direction does the main axis flow in?
84 pub flex_direction: FlexDirection,
85 /// Should elements wrap, or stay in a single line?
86 pub flex_wrap: FlexWrap,
87 /// Sets the initial main axis size of the item
88 pub flex_basis: Length,
89 /// The relative rate at which this item grows when it is expanding to fill space, 0.0 is the default value, and this value must be positive.
90 pub flex_grow: f32,
91 /// The relative rate at which this item shrinks when it is contracting to fit into space, 1.0 is the default value, and this value must be positive.
92 pub flex_shrink: f32,
93
94 /// The fill color of this element
95 pub background: Option<Fill>,
96
97 /// The border color of this element
98 pub border_color: Option<Hsla>,
99
100 /// The radius of the corners of this element
101 #[refineable]
102 pub corner_radii: Corners<AbsoluteLength>,
103
104 /// Box Shadow of the element
105 pub box_shadow: SmallVec<[BoxShadow; 2]>,
106
107 /// TEXT
108 pub text: TextStyleRefinement,
109
110 /// The mouse cursor style shown when the mouse pointer is over an element.
111 pub mouse_cursor: Option<CursorStyle>,
112
113 pub z_index: Option<u16>,
114
115 #[cfg(debug_assertions)]
116 pub debug: bool,
117 #[cfg(debug_assertions)]
118 pub debug_below: bool,
119}
120
121impl Styled for StyleRefinement {
122 fn style(&mut self) -> &mut StyleRefinement {
123 self
124 }
125}
126
127#[derive(Default, Clone, Copy, Debug, Eq, PartialEq)]
128pub enum Visibility {
129 #[default]
130 Visible,
131 Hidden,
132}
133
134#[derive(Clone, Debug)]
135pub struct BoxShadow {
136 pub color: Hsla,
137 pub offset: Point<Pixels>,
138 pub blur_radius: Pixels,
139 pub spread_radius: Pixels,
140}
141
142#[derive(Copy, Clone, Debug, Default, PartialEq, Eq)]
143pub enum WhiteSpace {
144 #[default]
145 Normal,
146 Nowrap,
147}
148
149#[derive(Refineable, Clone, Debug, PartialEq)]
150#[refineable(Debug)]
151pub struct TextStyle {
152 pub color: Hsla,
153 pub font_family: SharedString,
154 pub font_features: FontFeatures,
155 pub font_size: AbsoluteLength,
156 pub line_height: DefiniteLength,
157 pub font_weight: FontWeight,
158 pub font_style: FontStyle,
159 pub background_color: Option<Hsla>,
160 pub underline: Option<UnderlineStyle>,
161 pub white_space: WhiteSpace,
162}
163
164impl Default for TextStyle {
165 fn default() -> Self {
166 TextStyle {
167 color: black(),
168 // Helvetica is a web safe font, so it should be available
169 font_family: "Helvetica".into(),
170 font_features: FontFeatures::default(),
171 font_size: rems(1.).into(),
172 line_height: phi(),
173 font_weight: FontWeight::default(),
174 font_style: FontStyle::default(),
175 background_color: None,
176 underline: None,
177 white_space: WhiteSpace::Normal,
178 }
179 }
180}
181
182impl TextStyle {
183 pub fn highlight(mut self, style: impl Into<HighlightStyle>) -> Self {
184 let style = style.into();
185 if let Some(weight) = style.font_weight {
186 self.font_weight = weight;
187 }
188 if let Some(style) = style.font_style {
189 self.font_style = style;
190 }
191
192 if let Some(color) = style.color {
193 self.color = self.color.blend(color);
194 }
195
196 if let Some(factor) = style.fade_out {
197 self.color.fade_out(factor);
198 }
199
200 if let Some(background_color) = style.background_color {
201 self.background_color = Some(background_color);
202 }
203
204 if let Some(underline) = style.underline {
205 self.underline = Some(underline);
206 }
207
208 self
209 }
210
211 pub fn font(&self) -> Font {
212 Font {
213 family: self.font_family.clone(),
214 features: self.font_features,
215 weight: self.font_weight,
216 style: self.font_style,
217 }
218 }
219
220 /// Returns the rounded line height in pixels.
221 pub fn line_height_in_pixels(&self, rem_size: Pixels) -> Pixels {
222 self.line_height.to_pixels(self.font_size, rem_size).round()
223 }
224
225 pub fn to_run(&self, len: usize) -> TextRun {
226 TextRun {
227 len,
228 font: Font {
229 family: self.font_family.clone(),
230 features: Default::default(),
231 weight: self.font_weight,
232 style: self.font_style,
233 },
234 color: self.color,
235 background_color: self.background_color,
236 underline: self.underline,
237 }
238 }
239}
240
241#[derive(Copy, Clone, Debug, Default, PartialEq)]
242pub struct HighlightStyle {
243 pub color: Option<Hsla>,
244 pub font_weight: Option<FontWeight>,
245 pub font_style: Option<FontStyle>,
246 pub background_color: Option<Hsla>,
247 pub underline: Option<UnderlineStyle>,
248 pub fade_out: Option<f32>,
249}
250
251impl Eq for HighlightStyle {}
252
253impl Style {
254 pub fn text_style(&self) -> Option<&TextStyleRefinement> {
255 if self.text.is_some() {
256 Some(&self.text)
257 } else {
258 None
259 }
260 }
261
262 pub fn overflow_mask(
263 &self,
264 bounds: Bounds<Pixels>,
265 rem_size: Pixels,
266 ) -> Option<ContentMask<Pixels>> {
267 match self.overflow {
268 Point {
269 x: Overflow::Visible,
270 y: Overflow::Visible,
271 } => None,
272 _ => {
273 let mut min = bounds.origin;
274 let mut max = bounds.lower_right();
275
276 if self
277 .border_color
278 .map_or(false, |color| !color.is_transparent())
279 {
280 min.x += self.border_widths.left.to_pixels(rem_size);
281 max.x -= self.border_widths.right.to_pixels(rem_size);
282 min.y += self.border_widths.top.to_pixels(rem_size);
283 max.y -= self.border_widths.bottom.to_pixels(rem_size);
284 }
285
286 let bounds = match (
287 self.overflow.x == Overflow::Visible,
288 self.overflow.y == Overflow::Visible,
289 ) {
290 // x and y both visible
291 (true, true) => return None,
292 // x visible, y hidden
293 (true, false) => Bounds::from_corners(
294 point(min.x, bounds.origin.y),
295 point(max.x, bounds.lower_right().y),
296 ),
297 // x hidden, y visible
298 (false, true) => Bounds::from_corners(
299 point(bounds.origin.x, min.y),
300 point(bounds.lower_right().x, max.y),
301 ),
302 // both hidden
303 (false, false) => Bounds::from_corners(min, max),
304 };
305
306 Some(ContentMask { bounds })
307 }
308 }
309 }
310
311 /// Paints the background of an element styled with this style.
312 pub fn paint(
313 &self,
314 bounds: Bounds<Pixels>,
315 cx: &mut ElementContext,
316 continuation: impl FnOnce(&mut ElementContext),
317 ) {
318 #[cfg(debug_assertions)]
319 if self.debug_below {
320 cx.set_global(DebugBelow)
321 }
322
323 #[cfg(debug_assertions)]
324 if self.debug || cx.has_global::<DebugBelow>() {
325 cx.paint_quad(crate::outline(bounds, crate::red()));
326 }
327
328 let rem_size = cx.rem_size();
329
330 cx.with_z_index(0, |cx| {
331 cx.paint_shadows(
332 bounds,
333 self.corner_radii.to_pixels(bounds.size, rem_size),
334 &self.box_shadow,
335 );
336 });
337
338 let background_color = self.background.as_ref().and_then(Fill::color);
339 if background_color.map_or(false, |color| !color.is_transparent()) {
340 cx.with_z_index(1, |cx| {
341 let mut border_color = background_color.unwrap_or_default();
342 border_color.a = 0.;
343 cx.paint_quad(quad(
344 bounds,
345 self.corner_radii.to_pixels(bounds.size, rem_size),
346 background_color.unwrap_or_default(),
347 Edges::default(),
348 border_color,
349 ));
350 });
351 }
352
353 cx.with_z_index(2, |cx| {
354 continuation(cx);
355 });
356
357 if self.is_border_visible() {
358 cx.with_z_index(3, |cx| {
359 let corner_radii = self.corner_radii.to_pixels(bounds.size, rem_size);
360 let border_widths = self.border_widths.to_pixels(rem_size);
361 let max_border_width = border_widths.max();
362 let max_corner_radius = corner_radii.max();
363
364 let top_bounds = Bounds::from_corners(
365 bounds.origin,
366 bounds.upper_right()
367 + point(Pixels::ZERO, max_border_width.max(max_corner_radius)),
368 );
369 let bottom_bounds = Bounds::from_corners(
370 bounds.lower_left()
371 - point(Pixels::ZERO, max_border_width.max(max_corner_radius)),
372 bounds.lower_right(),
373 );
374 let left_bounds = Bounds::from_corners(
375 top_bounds.lower_left(),
376 bottom_bounds.origin + point(max_border_width, Pixels::ZERO),
377 );
378 let right_bounds = Bounds::from_corners(
379 top_bounds.lower_right() - point(max_border_width, Pixels::ZERO),
380 bottom_bounds.upper_right(),
381 );
382
383 let mut background = self.border_color.unwrap_or_default();
384 background.a = 0.;
385 let quad = quad(
386 bounds,
387 corner_radii,
388 background,
389 border_widths,
390 self.border_color.unwrap_or_default(),
391 );
392
393 cx.with_content_mask(Some(ContentMask { bounds: top_bounds }), |cx| {
394 cx.paint_quad(quad.clone());
395 });
396 cx.with_content_mask(
397 Some(ContentMask {
398 bounds: right_bounds,
399 }),
400 |cx| {
401 cx.paint_quad(quad.clone());
402 },
403 );
404 cx.with_content_mask(
405 Some(ContentMask {
406 bounds: bottom_bounds,
407 }),
408 |cx| {
409 cx.paint_quad(quad.clone());
410 },
411 );
412 cx.with_content_mask(
413 Some(ContentMask {
414 bounds: left_bounds,
415 }),
416 |cx| {
417 cx.paint_quad(quad);
418 },
419 );
420 });
421 }
422
423 #[cfg(debug_assertions)]
424 if self.debug_below {
425 cx.remove_global::<DebugBelow>();
426 }
427 }
428
429 fn is_border_visible(&self) -> bool {
430 self.border_color
431 .map_or(false, |color| !color.is_transparent())
432 && self.border_widths.any(|length| !length.is_zero())
433 }
434}
435
436impl Default for Style {
437 fn default() -> Self {
438 Style {
439 display: Display::Block,
440 visibility: Visibility::Visible,
441 overflow: Point {
442 x: Overflow::Visible,
443 y: Overflow::Visible,
444 },
445 scrollbar_width: 0.0,
446 position: Position::Relative,
447 inset: Edges::auto(),
448 margin: Edges::<Length>::zero(),
449 padding: Edges::<DefiniteLength>::zero(),
450 border_widths: Edges::<AbsoluteLength>::zero(),
451 size: Size::auto(),
452 min_size: Size::auto(),
453 max_size: Size::auto(),
454 aspect_ratio: None,
455 gap: Size::default(),
456 // Alignment
457 align_items: None,
458 align_self: None,
459 align_content: None,
460 justify_content: None,
461 // Flexbox
462 flex_direction: FlexDirection::Row,
463 flex_wrap: FlexWrap::NoWrap,
464 flex_grow: 0.0,
465 flex_shrink: 1.0,
466 flex_basis: Length::Auto,
467 background: None,
468 border_color: None,
469 corner_radii: Corners::default(),
470 box_shadow: Default::default(),
471 text: TextStyleRefinement::default(),
472 mouse_cursor: None,
473 z_index: None,
474
475 #[cfg(debug_assertions)]
476 debug: false,
477 #[cfg(debug_assertions)]
478 debug_below: false,
479 }
480 }
481}
482
483#[derive(Refineable, Copy, Clone, Default, Debug, PartialEq, Eq)]
484#[refineable(Debug)]
485pub struct UnderlineStyle {
486 pub thickness: Pixels,
487 pub color: Option<Hsla>,
488 pub wavy: bool,
489}
490
491#[derive(Clone, Debug)]
492pub enum Fill {
493 Color(Hsla),
494}
495
496impl Fill {
497 pub fn color(&self) -> Option<Hsla> {
498 match self {
499 Fill::Color(color) => Some(*color),
500 }
501 }
502}
503
504impl Default for Fill {
505 fn default() -> Self {
506 Self::Color(Hsla::default())
507 }
508}
509
510impl From<Hsla> for Fill {
511 fn from(color: Hsla) -> Self {
512 Self::Color(color)
513 }
514}
515
516impl From<Rgba> for Fill {
517 fn from(color: Rgba) -> Self {
518 Self::Color(color.into())
519 }
520}
521
522impl From<TextStyle> for HighlightStyle {
523 fn from(other: TextStyle) -> Self {
524 Self::from(&other)
525 }
526}
527
528impl From<&TextStyle> for HighlightStyle {
529 fn from(other: &TextStyle) -> Self {
530 Self {
531 color: Some(other.color),
532 font_weight: Some(other.font_weight),
533 font_style: Some(other.font_style),
534 background_color: other.background_color,
535 underline: other.underline,
536 fade_out: None,
537 }
538 }
539}
540
541impl HighlightStyle {
542 pub fn highlight(&mut self, other: HighlightStyle) {
543 match (self.color, other.color) {
544 (Some(self_color), Some(other_color)) => {
545 self.color = Some(Hsla::blend(other_color, self_color));
546 }
547 (None, Some(other_color)) => {
548 self.color = Some(other_color);
549 }
550 _ => {}
551 }
552
553 if other.font_weight.is_some() {
554 self.font_weight = other.font_weight;
555 }
556
557 if other.font_style.is_some() {
558 self.font_style = other.font_style;
559 }
560
561 if other.background_color.is_some() {
562 self.background_color = other.background_color;
563 }
564
565 if other.underline.is_some() {
566 self.underline = other.underline;
567 }
568
569 match (other.fade_out, self.fade_out) {
570 (Some(source_fade), None) => self.fade_out = Some(source_fade),
571 (Some(source_fade), Some(dest_fade)) => {
572 self.fade_out = Some((dest_fade * (1. + source_fade)).clamp(0., 1.));
573 }
574 _ => {}
575 }
576 }
577}
578
579impl From<Hsla> for HighlightStyle {
580 fn from(color: Hsla) -> Self {
581 Self {
582 color: Some(color),
583 ..Default::default()
584 }
585 }
586}
587
588impl From<FontWeight> for HighlightStyle {
589 fn from(font_weight: FontWeight) -> Self {
590 Self {
591 font_weight: Some(font_weight),
592 ..Default::default()
593 }
594 }
595}
596
597impl From<FontStyle> for HighlightStyle {
598 fn from(font_style: FontStyle) -> Self {
599 Self {
600 font_style: Some(font_style),
601 ..Default::default()
602 }
603 }
604}
605
606impl From<Rgba> for HighlightStyle {
607 fn from(color: Rgba) -> Self {
608 Self {
609 color: Some(color.into()),
610 ..Default::default()
611 }
612 }
613}
614
615pub fn combine_highlights(
616 a: impl IntoIterator<Item = (Range<usize>, HighlightStyle)>,
617 b: impl IntoIterator<Item = (Range<usize>, HighlightStyle)>,
618) -> impl Iterator<Item = (Range<usize>, HighlightStyle)> {
619 let mut endpoints = Vec::new();
620 let mut highlights = Vec::new();
621 for (range, highlight) in a.into_iter().chain(b) {
622 if !range.is_empty() {
623 let highlight_id = highlights.len();
624 endpoints.push((range.start, highlight_id, true));
625 endpoints.push((range.end, highlight_id, false));
626 highlights.push(highlight);
627 }
628 }
629 endpoints.sort_unstable_by_key(|(position, _, _)| *position);
630 let mut endpoints = endpoints.into_iter().peekable();
631
632 let mut active_styles = HashSet::default();
633 let mut ix = 0;
634 iter::from_fn(move || {
635 while let Some((endpoint_ix, highlight_id, is_start)) = endpoints.peek() {
636 let prev_index = mem::replace(&mut ix, *endpoint_ix);
637 if ix > prev_index && !active_styles.is_empty() {
638 let mut current_style = HighlightStyle::default();
639 for highlight_id in &active_styles {
640 current_style.highlight(highlights[*highlight_id]);
641 }
642 return Some((prev_index..ix, current_style));
643 }
644
645 if *is_start {
646 active_styles.insert(*highlight_id);
647 } else {
648 active_styles.remove(highlight_id);
649 }
650 endpoints.next();
651 }
652 None
653 })
654}
655
656#[cfg(test)]
657mod tests {
658 use crate::{blue, green, red, yellow};
659
660 use super::*;
661
662 #[test]
663 fn test_combine_highlights() {
664 assert_eq!(
665 combine_highlights(
666 [
667 (0..5, green().into()),
668 (4..10, FontWeight::BOLD.into()),
669 (15..20, yellow().into()),
670 ],
671 [
672 (2..6, FontStyle::Italic.into()),
673 (1..3, blue().into()),
674 (21..23, red().into()),
675 ]
676 )
677 .collect::<Vec<_>>(),
678 [
679 (
680 0..1,
681 HighlightStyle {
682 color: Some(green()),
683 ..Default::default()
684 }
685 ),
686 (
687 1..2,
688 HighlightStyle {
689 color: Some(green()),
690 ..Default::default()
691 }
692 ),
693 (
694 2..3,
695 HighlightStyle {
696 color: Some(green()),
697 font_style: Some(FontStyle::Italic),
698 ..Default::default()
699 }
700 ),
701 (
702 3..4,
703 HighlightStyle {
704 color: Some(green()),
705 font_style: Some(FontStyle::Italic),
706 ..Default::default()
707 }
708 ),
709 (
710 4..5,
711 HighlightStyle {
712 color: Some(green()),
713 font_weight: Some(FontWeight::BOLD),
714 font_style: Some(FontStyle::Italic),
715 ..Default::default()
716 }
717 ),
718 (
719 5..6,
720 HighlightStyle {
721 font_weight: Some(FontWeight::BOLD),
722 font_style: Some(FontStyle::Italic),
723 ..Default::default()
724 }
725 ),
726 (
727 6..10,
728 HighlightStyle {
729 font_weight: Some(FontWeight::BOLD),
730 ..Default::default()
731 }
732 ),
733 (
734 15..20,
735 HighlightStyle {
736 color: Some(yellow()),
737 ..Default::default()
738 }
739 ),
740 (
741 21..23,
742 HighlightStyle {
743 color: Some(red()),
744 ..Default::default()
745 }
746 )
747 ]
748 );
749 }
750}