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layout/taffy/stylo_taffy/
convert.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use style::Atom;
6use stylo_atoms::atom;
7use taffy::MaxTrackSizingFunction;
8use taffy::style_helpers::*;
9
10use super::stylo;
11
12#[inline]
13pub fn length_percentage(val: &stylo::LengthPercentage) -> taffy::LengthPercentage {
14    match val.unpack() {
15        stylo::UnpackedLengthPercentage::Length(len) => length(len.px()),
16        stylo::UnpackedLengthPercentage::Percentage(percentage) => percent(percentage.0),
17        stylo::UnpackedLengthPercentage::Calc(calc_ref) => {
18            let calc_ptr = calc_ref as *const stylo::CalcLengthPercentage as *const ();
19            taffy::LengthPercentage::calc(calc_ptr)
20        },
21    }
22}
23
24#[inline]
25pub fn dimension(val: &stylo::Size) -> taffy::Dimension {
26    match val {
27        stylo::Size::LengthPercentage(val) => length_percentage(&val.0).into(),
28        stylo::Size::Auto => taffy::Dimension::AUTO,
29
30        // TODO: implement other values in Taffy
31        stylo::Size::MaxContent => taffy::Dimension::AUTO,
32        stylo::Size::MinContent => taffy::Dimension::AUTO,
33        stylo::Size::FitContent => taffy::Dimension::AUTO,
34        stylo::Size::FitContentFunction(_) => taffy::Dimension::AUTO,
35        stylo::Size::Stretch | stylo::Size::WebkitFillAvailable => taffy::Dimension::AUTO,
36
37        // Anchor positioning will be flagged off for time being
38        stylo::Size::AnchorSizeFunction(_) => unreachable!(),
39        stylo::Size::AnchorContainingCalcFunction(_) => unreachable!(),
40    }
41}
42
43#[inline]
44pub fn max_size_dimension(val: &stylo::MaxSize) -> taffy::Dimension {
45    match val {
46        stylo::MaxSize::LengthPercentage(val) => length_percentage(&val.0).into(),
47        stylo::MaxSize::None => taffy::Dimension::AUTO,
48
49        // TODO: implement other values in Taffy
50        stylo::MaxSize::MaxContent => taffy::Dimension::AUTO,
51        stylo::MaxSize::MinContent => taffy::Dimension::AUTO,
52        stylo::MaxSize::FitContent => taffy::Dimension::AUTO,
53        stylo::MaxSize::FitContentFunction(_) => taffy::Dimension::AUTO,
54        stylo::MaxSize::Stretch | stylo::MaxSize::WebkitFillAvailable => taffy::Dimension::AUTO,
55
56        // Anchor positioning will be flagged off for time being
57        stylo::MaxSize::AnchorSizeFunction(_) => unreachable!(),
58        stylo::MaxSize::AnchorContainingCalcFunction(_) => unreachable!(),
59    }
60}
61
62#[inline]
63pub fn margin(val: &stylo::MarginVal) -> taffy::LengthPercentageAuto {
64    match val {
65        stylo::MarginVal::Auto => taffy::LengthPercentageAuto::AUTO,
66        stylo::MarginVal::LengthPercentage(val) => length_percentage(val).into(),
67
68        // Anchor positioning will be flagged off for time being
69        stylo::MarginVal::AnchorSizeFunction(_) => unreachable!(),
70        stylo::MarginVal::AnchorContainingCalcFunction(_) => unreachable!(),
71    }
72}
73
74#[inline]
75pub fn inset(val: &stylo::InsetVal) -> taffy::LengthPercentageAuto {
76    match val {
77        stylo::InsetVal::Auto => taffy::LengthPercentageAuto::AUTO,
78        stylo::InsetVal::LengthPercentage(val) => length_percentage(val).into(),
79
80        // Anchor positioning will be flagged off for time being
81        stylo::InsetVal::AnchorSizeFunction(_) => unreachable!(),
82        stylo::InsetVal::AnchorFunction(_) => unreachable!(),
83        stylo::InsetVal::AnchorContainingCalcFunction(_) => unreachable!(),
84    }
85}
86
87#[inline]
88pub fn is_block(input: stylo::Display) -> bool {
89    matches!(input.outside(), stylo::DisplayOutside::Block) &&
90        matches!(
91            input.inside(),
92            stylo::DisplayInside::Flow | stylo::DisplayInside::FlowRoot
93        )
94}
95
96#[inline]
97pub fn box_generation_mode(input: stylo::Display) -> taffy::BoxGenerationMode {
98    match input.inside() {
99        stylo::DisplayInside::None => taffy::BoxGenerationMode::None,
100        _ => taffy::BoxGenerationMode::Normal,
101    }
102}
103
104#[inline]
105pub fn box_sizing(input: stylo::BoxSizing) -> taffy::BoxSizing {
106    match input {
107        stylo::BoxSizing::BorderBox => taffy::BoxSizing::BorderBox,
108        stylo::BoxSizing::ContentBox => taffy::BoxSizing::ContentBox,
109    }
110}
111
112#[inline]
113pub fn direction(input: stylo::Direction) -> taffy::Direction {
114    match input {
115        stylo::Direction::Ltr => taffy::Direction::Ltr,
116        stylo::Direction::Rtl => taffy::Direction::Rtl,
117    }
118}
119
120#[inline]
121pub fn position(input: stylo::Position) -> taffy::Position {
122    match input {
123        // TODO: support position:static
124        stylo::Position::Relative => taffy::Position::Relative,
125        stylo::Position::Static => taffy::Position::Relative,
126
127        // TODO: support position:fixed and sticky
128        stylo::Position::Absolute => taffy::Position::Absolute,
129        stylo::Position::Fixed => taffy::Position::Absolute,
130        stylo::Position::Sticky => taffy::Position::Relative,
131    }
132}
133
134#[inline]
135pub fn overflow(input: stylo::Overflow) -> taffy::Overflow {
136    // TODO: Enable Overflow::Clip in servo configuration of stylo
137    match input {
138        stylo::Overflow::Visible => taffy::Overflow::Visible,
139        stylo::Overflow::Hidden => taffy::Overflow::Hidden,
140        stylo::Overflow::Scroll => taffy::Overflow::Scroll,
141        stylo::Overflow::Clip => taffy::Overflow::Clip,
142        // TODO: Support Overflow::Auto in Taffy
143        stylo::Overflow::Auto => taffy::Overflow::Scroll,
144    }
145}
146
147#[inline]
148pub fn aspect_ratio(input: stylo::AspectRatio) -> Option<f32> {
149    match input.ratio {
150        stylo::PreferredRatio::None => None,
151        stylo::PreferredRatio::Ratio(val) => Some(val.0.0 / val.1.0),
152    }
153}
154
155#[inline]
156pub fn content_alignment(input: stylo::ContentDistribution) -> Option<taffy::AlignContent> {
157    let keyword = match input.primary().value() {
158        stylo::AlignFlags::NORMAL => return None,
159        stylo::AlignFlags::AUTO => return None,
160        stylo::AlignFlags::START => taffy::AlignContentKeyword::Start,
161        stylo::AlignFlags::END => taffy::AlignContentKeyword::End,
162        stylo::AlignFlags::LEFT => taffy::AlignContentKeyword::Start,
163        stylo::AlignFlags::RIGHT => taffy::AlignContentKeyword::End,
164        stylo::AlignFlags::FLEX_START => taffy::AlignContentKeyword::FlexStart,
165        stylo::AlignFlags::STRETCH => taffy::AlignContentKeyword::Stretch,
166        stylo::AlignFlags::FLEX_END => taffy::AlignContentKeyword::FlexEnd,
167        stylo::AlignFlags::CENTER => taffy::AlignContentKeyword::Center,
168        stylo::AlignFlags::SPACE_BETWEEN => taffy::AlignContentKeyword::SpaceBetween,
169        stylo::AlignFlags::SPACE_AROUND => taffy::AlignContentKeyword::SpaceAround,
170        stylo::AlignFlags::SPACE_EVENLY => taffy::AlignContentKeyword::SpaceEvenly,
171        // Should never be hit. But no real reason to panic here.
172        _ => return None,
173    };
174
175    let safety = match input.primary().flags() {
176        stylo::AlignFlags::SAFE => taffy::AlignmentSafety::Safe,
177        _ => taffy::AlignmentSafety::Unsafe,
178    };
179
180    Some(taffy::AlignContent { keyword, safety })
181}
182
183#[inline]
184pub fn item_alignment(input: stylo::AlignFlags) -> Option<taffy::AlignItems> {
185    let keyword = match input.value() {
186        stylo::AlignFlags::AUTO => return None,
187        stylo::AlignFlags::NORMAL => taffy::AlignItemsKeyword::Stretch,
188        stylo::AlignFlags::STRETCH => taffy::AlignItemsKeyword::Stretch,
189        stylo::AlignFlags::FLEX_START => taffy::AlignItemsKeyword::FlexStart,
190        stylo::AlignFlags::FLEX_END => taffy::AlignItemsKeyword::FlexEnd,
191        stylo::AlignFlags::SELF_START => taffy::AlignItemsKeyword::Start,
192        stylo::AlignFlags::SELF_END => taffy::AlignItemsKeyword::End,
193        stylo::AlignFlags::START => taffy::AlignItemsKeyword::Start,
194        stylo::AlignFlags::END => taffy::AlignItemsKeyword::End,
195        stylo::AlignFlags::LEFT => taffy::AlignItemsKeyword::Start,
196        stylo::AlignFlags::RIGHT => taffy::AlignItemsKeyword::End,
197        stylo::AlignFlags::CENTER => taffy::AlignItemsKeyword::Center,
198        stylo::AlignFlags::BASELINE => taffy::AlignItemsKeyword::Baseline,
199        // Should never be hit. But no real reason to panic here.
200        _ => return None,
201    };
202
203    let safety = match input.flags() {
204        stylo::AlignFlags::SAFE => taffy::AlignmentSafety::Safe,
205        _ => taffy::AlignmentSafety::Unsafe,
206    };
207
208    Some(taffy::AlignItems { keyword, safety })
209}
210
211#[inline]
212pub fn gap(input: &stylo::Gap) -> taffy::LengthPercentage {
213    match input {
214        // For Flexbox and CSS Grid the "normal" value is 0px. This may need to be updated
215        // if we ever implement multi-column layout.
216        stylo::Gap::Normal => taffy::LengthPercentage::ZERO,
217        stylo::Gap::LengthPercentage(val) => length_percentage(&val.0),
218    }
219}
220
221// CSS Grid styles
222// ===============
223
224#[inline]
225pub fn grid_auto_flow(input: stylo::GridAutoFlow) -> taffy::GridAutoFlow {
226    let is_row = input.contains(stylo::GridAutoFlow::ROW);
227    let is_dense = input.contains(stylo::GridAutoFlow::DENSE);
228
229    match (is_row, is_dense) {
230        (true, false) => taffy::GridAutoFlow::Row,
231        (true, true) => taffy::GridAutoFlow::RowDense,
232        (false, false) => taffy::GridAutoFlow::Column,
233        (false, true) => taffy::GridAutoFlow::ColumnDense,
234    }
235}
236
237#[inline]
238pub fn grid_line(input: &stylo::GridLine) -> taffy::GridPlacement<Atom> {
239    if input.is_auto() {
240        taffy::GridPlacement::Auto
241    } else if input.is_span {
242        if input.ident.0 != atom!("") {
243            taffy::GridPlacement::NamedSpan(
244                input.ident.0.clone(),
245                input.line_num.try_into().unwrap(),
246            )
247        } else {
248            taffy::GridPlacement::Span(input.line_num as u16)
249        }
250    } else if input.ident.0 != atom!("") {
251        taffy::GridPlacement::NamedLine(input.ident.0.clone(), input.line_num as i16)
252    } else if input.line_num != 0 {
253        taffy::style_helpers::line(input.line_num as i16)
254    } else {
255        taffy::GridPlacement::Auto
256    }
257}
258
259#[inline]
260pub fn track_repeat(input: stylo::RepeatCount<i32>) -> taffy::RepetitionCount {
261    match input {
262        stylo::RepeatCount::Number(val) => taffy::RepetitionCount::Count(val.try_into().unwrap()),
263        stylo::RepeatCount::AutoFill => taffy::RepetitionCount::AutoFill,
264        stylo::RepeatCount::AutoFit => taffy::RepetitionCount::AutoFit,
265    }
266}
267
268#[inline]
269pub fn track_size(input: &stylo::TrackSize<stylo::LengthPercentage>) -> taffy::TrackSizingFunction {
270    match input {
271        stylo::TrackSize::Breadth(breadth) => taffy::MinMax {
272            min: min_track(breadth),
273            max: max_track(breadth),
274        },
275        stylo::TrackSize::Minmax(min, max) => taffy::MinMax {
276            min: min_track(min),
277            max: max_track(max),
278        },
279        stylo::TrackSize::FitContent(limit) => taffy::MinMax {
280            min: taffy::MinTrackSizingFunction::AUTO,
281            max: match limit {
282                stylo::TrackBreadth::Breadth(lp) => {
283                    MaxTrackSizingFunction::fit_content(length_percentage(lp))
284                },
285
286                // Are these valid? Taffy doesn't support this in any case
287                stylo::TrackBreadth::Flex(_) => unreachable!(),
288                stylo::TrackBreadth::Auto => unreachable!(),
289                stylo::TrackBreadth::MinContent => unreachable!(),
290                stylo::TrackBreadth::MaxContent => unreachable!(),
291            },
292        },
293    }
294}
295
296#[inline]
297pub fn min_track(
298    input: &stylo::TrackBreadth<stylo::LengthPercentage>,
299) -> taffy::MinTrackSizingFunction {
300    match input {
301        stylo::TrackBreadth::Breadth(lp) => length_percentage(lp).into(),
302        stylo::TrackBreadth::Flex(_) => taffy::MinTrackSizingFunction::AUTO,
303        stylo::TrackBreadth::Auto => taffy::MinTrackSizingFunction::AUTO,
304        stylo::TrackBreadth::MinContent => taffy::MinTrackSizingFunction::MIN_CONTENT,
305        stylo::TrackBreadth::MaxContent => taffy::MinTrackSizingFunction::MAX_CONTENT,
306    }
307}
308
309#[inline]
310pub fn max_track(
311    input: &stylo::TrackBreadth<stylo::LengthPercentage>,
312) -> taffy::MaxTrackSizingFunction {
313    match input {
314        stylo::TrackBreadth::Breadth(lp) => length_percentage(lp).into(),
315        stylo::TrackBreadth::Flex(val) => fr(val.0),
316        stylo::TrackBreadth::Auto => taffy::MaxTrackSizingFunction::AUTO,
317        stylo::TrackBreadth::MinContent => taffy::MaxTrackSizingFunction::MIN_CONTENT,
318        stylo::TrackBreadth::MaxContent => taffy::MaxTrackSizingFunction::MAX_CONTENT,
319    }
320}