1use crate::{
2 Bounds, DevicePixels, Font, FontFallbacks, FontFeatures, FontId, FontMetrics, FontRun,
3 FontStyle, FontWeight, GlyphId, LineLayout, Pixels, PlatformTextSystem, Point,
4 RenderGlyphParams, Result, SUBPIXEL_VARIANTS_X, ShapedGlyph, ShapedRun, SharedString, Size,
5 point, px, size, swap_rgba_pa_to_bgra,
6};
7use anyhow::anyhow;
8use cocoa::appkit::CGFloat;
9use collections::HashMap;
10use core_foundation::{
11 attributed_string::CFMutableAttributedString,
12 base::{CFRange, TCFType},
13 number::CFNumber,
14 string::CFString,
15};
16use core_graphics::{
17 base::{CGGlyph, kCGImageAlphaPremultipliedLast},
18 color_space::CGColorSpace,
19 context::{CGContext, CGTextDrawingMode},
20 display::CGPoint,
21};
22use core_text::{
23 font::CTFont,
24 font_descriptor::{
25 kCTFontSlantTrait, kCTFontSymbolicTrait, kCTFontWeightTrait, kCTFontWidthTrait,
26 },
27 line::CTLine,
28 string_attributes::kCTFontAttributeName,
29};
30use font_kit::{
31 font::Font as FontKitFont,
32 handle::Handle,
33 hinting::HintingOptions,
34 metrics::Metrics,
35 properties::{Style as FontkitStyle, Weight as FontkitWeight},
36 source::SystemSource,
37 sources::mem::MemSource,
38};
39use parking_lot::{RwLock, RwLockUpgradableReadGuard};
40use pathfinder_geometry::{
41 rect::{RectF, RectI},
42 transform2d::Transform2F,
43 vector::{Vector2F, Vector2I},
44};
45use smallvec::SmallVec;
46use std::{borrow::Cow, char, convert::TryFrom, sync::Arc};
47
48use super::open_type::apply_features_and_fallbacks;
49
50#[allow(non_upper_case_globals)]
51const kCGImageAlphaOnly: u32 = 7;
52
53pub(crate) struct MacTextSystem(RwLock<MacTextSystemState>);
54
55#[derive(Clone, PartialEq, Eq, Hash)]
56struct FontKey {
57 font_family: SharedString,
58 font_features: FontFeatures,
59 font_fallbacks: Option<FontFallbacks>,
60}
61
62struct MacTextSystemState {
63 memory_source: MemSource,
64 system_source: SystemSource,
65 fonts: Vec<FontKitFont>,
66 font_selections: HashMap<Font, FontId>,
67 font_ids_by_postscript_name: HashMap<String, FontId>,
68 font_ids_by_font_key: HashMap<FontKey, SmallVec<[FontId; 4]>>,
69 postscript_names_by_font_id: HashMap<FontId, String>,
70 zwnjs_scratch_space: Vec<(usize, usize)>,
71}
72
73impl MacTextSystem {
74 pub(crate) fn new() -> Self {
75 Self(RwLock::new(MacTextSystemState {
76 memory_source: MemSource::empty(),
77 system_source: SystemSource::new(),
78 fonts: Vec::new(),
79 font_selections: HashMap::default(),
80 font_ids_by_postscript_name: HashMap::default(),
81 font_ids_by_font_key: HashMap::default(),
82 postscript_names_by_font_id: HashMap::default(),
83 zwnjs_scratch_space: Vec::new(),
84 }))
85 }
86}
87
88impl Default for MacTextSystem {
89 fn default() -> Self {
90 Self::new()
91 }
92}
93
94impl PlatformTextSystem for MacTextSystem {
95 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
96 self.0.write().add_fonts(fonts)
97 }
98
99 fn all_font_names(&self) -> Vec<String> {
100 let mut names = Vec::new();
101 let collection = core_text::font_collection::create_for_all_families();
102 let Some(descriptors) = collection.get_descriptors() else {
103 return names;
104 };
105 for descriptor in descriptors.into_iter() {
106 names.extend(lenient_font_attributes::family_name(&descriptor));
107 }
108 if let Ok(fonts_in_memory) = self.0.read().memory_source.all_families() {
109 names.extend(fonts_in_memory);
110 }
111 names
112 }
113
114 fn font_id(&self, font: &Font) -> Result<FontId> {
115 let lock = self.0.upgradable_read();
116 if let Some(font_id) = lock.font_selections.get(font) {
117 Ok(*font_id)
118 } else {
119 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
120 let font_key = FontKey {
121 font_family: font.family.clone(),
122 font_features: font.features.clone(),
123 font_fallbacks: font.fallbacks.clone(),
124 };
125 let candidates = if let Some(font_ids) = lock.font_ids_by_font_key.get(&font_key) {
126 font_ids.as_slice()
127 } else {
128 let font_ids =
129 lock.load_family(&font.family, &font.features, font.fallbacks.as_ref())?;
130 lock.font_ids_by_font_key.insert(font_key.clone(), font_ids);
131 lock.font_ids_by_font_key[&font_key].as_ref()
132 };
133
134 let candidate_properties = candidates
135 .iter()
136 .map(|font_id| lock.fonts[font_id.0].properties())
137 .collect::<SmallVec<[_; 4]>>();
138
139 let ix = font_kit::matching::find_best_match(
140 &candidate_properties,
141 &font_kit::properties::Properties {
142 style: font.style.into(),
143 weight: font.weight.into(),
144 stretch: Default::default(),
145 },
146 )?;
147
148 let font_id = candidates[ix];
149 lock.font_selections.insert(font.clone(), font_id);
150 Ok(font_id)
151 }
152 }
153
154 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
155 self.0.read().fonts[font_id.0].metrics().into()
156 }
157
158 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
159 Ok(self.0.read().fonts[font_id.0]
160 .typographic_bounds(glyph_id.0)?
161 .into())
162 }
163
164 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
165 self.0.read().advance(font_id, glyph_id)
166 }
167
168 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
169 self.0.read().glyph_for_char(font_id, ch)
170 }
171
172 fn glyph_raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
173 self.0.read().raster_bounds(params)
174 }
175
176 fn rasterize_glyph(
177 &self,
178 glyph_id: &RenderGlyphParams,
179 raster_bounds: Bounds<DevicePixels>,
180 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
181 self.0.read().rasterize_glyph(glyph_id, raster_bounds)
182 }
183
184 fn layout_line(&self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
185 self.0.write().layout_line(text, font_size, font_runs)
186 }
187}
188
189impl MacTextSystemState {
190 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
191 let fonts = fonts
192 .into_iter()
193 .map(|bytes| match bytes {
194 Cow::Borrowed(embedded_font) => {
195 let data_provider = unsafe {
196 core_graphics::data_provider::CGDataProvider::from_slice(embedded_font)
197 };
198 let font = core_graphics::font::CGFont::from_data_provider(data_provider)
199 .map_err(|()| anyhow!("Could not load an embedded font."))?;
200 let font = font_kit::loaders::core_text::Font::from_core_graphics_font(font);
201 Ok(Handle::from_native(&font))
202 }
203 Cow::Owned(bytes) => Ok(Handle::from_memory(Arc::new(bytes), 0)),
204 })
205 .collect::<Result<Vec<_>>>()?;
206 self.memory_source.add_fonts(fonts.into_iter())?;
207 Ok(())
208 }
209
210 fn load_family(
211 &mut self,
212 name: &str,
213 features: &FontFeatures,
214 fallbacks: Option<&FontFallbacks>,
215 ) -> Result<SmallVec<[FontId; 4]>> {
216 let name = crate::text_system::font_name_with_fallbacks(name, ".AppleSystemUIFont");
217
218 let mut font_ids = SmallVec::new();
219 let family = self
220 .memory_source
221 .select_family_by_name(name)
222 .or_else(|_| self.system_source.select_family_by_name(name))?;
223 for font in family.fonts() {
224 let mut font = font.load()?;
225
226 apply_features_and_fallbacks(&mut font, features, fallbacks)?;
227 // This block contains a precautionary fix to guard against loading fonts
228 // that might cause panics due to `.unwrap()`s up the chain.
229 {
230 // We use the 'm' character for text measurements in various spots
231 // (e.g., the editor). However, at time of writing some of those usages
232 // will panic if the font has no 'm' glyph.
233 //
234 // Therefore, we check up front that the font has the necessary glyph.
235 let has_m_glyph = font.glyph_for_char('m').is_some();
236
237 // HACK: The 'Segoe Fluent Icons' font does not have an 'm' glyph,
238 // but we need to be able to load it for rendering Windows icons in
239 // the Storybook (on macOS).
240 let is_segoe_fluent_icons = font.full_name() == "Segoe Fluent Icons";
241
242 if !has_m_glyph && !is_segoe_fluent_icons {
243 // I spent far too long trying to track down why a font missing the 'm'
244 // character wasn't loading. This log statement will hopefully save
245 // someone else from suffering the same fate.
246 log::warn!(
247 "font '{}' has no 'm' character and was not loaded",
248 font.full_name()
249 );
250 continue;
251 }
252 }
253
254 // We've seen a number of panics in production caused by calling font.properties()
255 // which unwraps a downcast to CFNumber. This is an attempt to avoid the panic,
256 // and to try and identify the incalcitrant font.
257 let traits = font.native_font().all_traits();
258 if unsafe {
259 !(traits
260 .get(kCTFontSymbolicTrait)
261 .downcast::<CFNumber>()
262 .is_some()
263 && traits
264 .get(kCTFontWidthTrait)
265 .downcast::<CFNumber>()
266 .is_some()
267 && traits
268 .get(kCTFontWeightTrait)
269 .downcast::<CFNumber>()
270 .is_some()
271 && traits
272 .get(kCTFontSlantTrait)
273 .downcast::<CFNumber>()
274 .is_some())
275 } {
276 log::error!(
277 "Failed to read traits for font {:?}",
278 font.postscript_name().unwrap()
279 );
280 continue;
281 }
282
283 let font_id = FontId(self.fonts.len());
284 font_ids.push(font_id);
285 let postscript_name = font.postscript_name().unwrap();
286 self.font_ids_by_postscript_name
287 .insert(postscript_name.clone(), font_id);
288 self.postscript_names_by_font_id
289 .insert(font_id, postscript_name);
290 self.fonts.push(font);
291 }
292 Ok(font_ids)
293 }
294
295 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
296 Ok(self.fonts[font_id.0].advance(glyph_id.0)?.into())
297 }
298
299 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
300 self.fonts[font_id.0].glyph_for_char(ch).map(GlyphId)
301 }
302
303 fn id_for_native_font(&mut self, requested_font: CTFont) -> FontId {
304 let postscript_name = requested_font.postscript_name();
305 if let Some(font_id) = self.font_ids_by_postscript_name.get(&postscript_name) {
306 *font_id
307 } else {
308 let font_id = FontId(self.fonts.len());
309 self.font_ids_by_postscript_name
310 .insert(postscript_name.clone(), font_id);
311 self.postscript_names_by_font_id
312 .insert(font_id, postscript_name);
313 self.fonts
314 .push(font_kit::font::Font::from_core_graphics_font(
315 requested_font.copy_to_CGFont(),
316 ));
317 font_id
318 }
319 }
320
321 fn is_emoji(&self, font_id: FontId) -> bool {
322 self.postscript_names_by_font_id
323 .get(&font_id)
324 .is_some_and(|postscript_name| {
325 postscript_name == "AppleColorEmoji" || postscript_name == ".AppleColorEmojiUI"
326 })
327 }
328
329 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
330 let font = &self.fonts[params.font_id.0];
331 let scale = Transform2F::from_scale(params.scale_factor);
332 Ok(font
333 .raster_bounds(
334 params.glyph_id.0,
335 params.font_size.into(),
336 scale,
337 HintingOptions::None,
338 font_kit::canvas::RasterizationOptions::GrayscaleAa,
339 )?
340 .into())
341 }
342
343 fn rasterize_glyph(
344 &self,
345 params: &RenderGlyphParams,
346 glyph_bounds: Bounds<DevicePixels>,
347 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
348 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
349 anyhow::bail!("glyph bounds are empty");
350 } else {
351 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
352 let mut bitmap_size = glyph_bounds.size;
353 if params.subpixel_variant.x > 0 {
354 bitmap_size.width += DevicePixels(1);
355 }
356 if params.subpixel_variant.y > 0 {
357 bitmap_size.height += DevicePixels(1);
358 }
359 let bitmap_size = bitmap_size;
360
361 let mut bytes;
362 let cx;
363 if params.is_emoji {
364 bytes = vec![0; bitmap_size.width.0 as usize * 4 * bitmap_size.height.0 as usize];
365 cx = CGContext::create_bitmap_context(
366 Some(bytes.as_mut_ptr() as *mut _),
367 bitmap_size.width.0 as usize,
368 bitmap_size.height.0 as usize,
369 8,
370 bitmap_size.width.0 as usize * 4,
371 &CGColorSpace::create_device_rgb(),
372 kCGImageAlphaPremultipliedLast,
373 );
374 } else {
375 bytes = vec![0; bitmap_size.width.0 as usize * bitmap_size.height.0 as usize];
376 cx = CGContext::create_bitmap_context(
377 Some(bytes.as_mut_ptr() as *mut _),
378 bitmap_size.width.0 as usize,
379 bitmap_size.height.0 as usize,
380 8,
381 bitmap_size.width.0 as usize,
382 &CGColorSpace::create_device_gray(),
383 kCGImageAlphaOnly,
384 );
385 }
386
387 // Move the origin to bottom left and account for scaling, this
388 // makes drawing text consistent with the font-kit's raster_bounds.
389 cx.translate(
390 -glyph_bounds.origin.x.0 as CGFloat,
391 (glyph_bounds.origin.y.0 + glyph_bounds.size.height.0) as CGFloat,
392 );
393 cx.scale(
394 params.scale_factor as CGFloat,
395 params.scale_factor as CGFloat,
396 );
397
398 let subpixel_shift = params
399 .subpixel_variant
400 .map(|v| v as f32 / SUBPIXEL_VARIANTS_X as f32);
401 cx.set_text_drawing_mode(CGTextDrawingMode::CGTextFill);
402 cx.set_gray_fill_color(0.0, 1.0);
403 cx.set_allows_antialiasing(true);
404 cx.set_should_antialias(true);
405 cx.set_allows_font_subpixel_positioning(true);
406 cx.set_should_subpixel_position_fonts(true);
407 cx.set_allows_font_subpixel_quantization(false);
408 cx.set_should_subpixel_quantize_fonts(false);
409 self.fonts[params.font_id.0]
410 .native_font()
411 .clone_with_font_size(f32::from(params.font_size) as CGFloat)
412 .draw_glyphs(
413 &[params.glyph_id.0 as CGGlyph],
414 &[CGPoint::new(
415 (subpixel_shift.x / params.scale_factor) as CGFloat,
416 (subpixel_shift.y / params.scale_factor) as CGFloat,
417 )],
418 cx,
419 );
420
421 if params.is_emoji {
422 // Convert from RGBA with premultiplied alpha to BGRA with straight alpha.
423 for pixel in bytes.chunks_exact_mut(4) {
424 swap_rgba_pa_to_bgra(pixel);
425 }
426 }
427
428 Ok((bitmap_size, bytes))
429 }
430 }
431
432 fn layout_line(&mut self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
433 const ZWNJ: char = '\u{200C}';
434 const ZWNJ_STR: &str = "\u{200C}";
435 const ZWNJ_SIZE_16: usize = ZWNJ.len_utf16();
436
437 self.zwnjs_scratch_space.clear();
438 // Construct the attributed string, converting UTF8 ranges to UTF16 ranges.
439 let mut string = CFMutableAttributedString::new();
440 let mut max_ascent = 0.0f32;
441 let mut max_descent = 0.0f32;
442
443 {
444 let mut ix_converter = StringIndexConverter::new(&text);
445 let mut last_font_run = None;
446 for run in font_runs {
447 let text = &text[ix_converter.utf8_ix..][..run.len];
448 // if the fonts are the same, we need to disconnect the text with a ZWNJ
449 // to prevent core text from forming ligatures between them
450 let needs_zwnj = last_font_run.replace(run.font_id) == Some(run.font_id);
451
452 let n_zwnjs = self.zwnjs_scratch_space.len();
453 let utf16_start = ix_converter.utf16_ix + n_zwnjs * ZWNJ_SIZE_16;
454 ix_converter.advance_to_utf8_ix(ix_converter.utf8_ix + run.len);
455
456 string.replace_str(&CFString::new(text), CFRange::init(utf16_start as isize, 0));
457 if needs_zwnj {
458 let zwnjs_pos = string.char_len();
459 self.zwnjs_scratch_space.push((n_zwnjs, zwnjs_pos as usize));
460 string.replace_str(
461 &CFString::from_static_string(ZWNJ_STR),
462 CFRange::init(zwnjs_pos, 0),
463 );
464 }
465 let utf16_end = string.char_len() as usize;
466
467 let cf_range =
468 CFRange::init(utf16_start as isize, (utf16_end - utf16_start) as isize);
469 let font = &self.fonts[run.font_id.0];
470
471 let font_metrics = font.metrics();
472 let font_scale = font_size.0 / font_metrics.units_per_em as f32;
473 max_ascent = max_ascent.max(font_metrics.ascent * font_scale);
474 max_descent = max_descent.max(-font_metrics.descent * font_scale);
475
476 unsafe {
477 string.set_attribute(
478 cf_range,
479 kCTFontAttributeName,
480 &font.native_font().clone_with_font_size(font_size.into()),
481 );
482 }
483 }
484 }
485 // Retrieve the glyphs from the shaped line, converting UTF16 offsets to UTF8 offsets.
486 let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
487 let glyph_runs = line.glyph_runs();
488 let mut runs = <Vec<ShapedRun>>::with_capacity(glyph_runs.len() as usize);
489 let mut ix_converter = StringIndexConverter::new(text);
490 for run in glyph_runs.into_iter() {
491 let attributes = run.attributes().unwrap();
492 let font = unsafe {
493 attributes
494 .get(kCTFontAttributeName)
495 .downcast::<CTFont>()
496 .unwrap()
497 };
498 let font_id = self.id_for_native_font(font);
499
500 let mut glyphs = match runs.last_mut() {
501 Some(run) if run.font_id == font_id => &mut run.glyphs,
502 _ => {
503 runs.push(ShapedRun {
504 font_id,
505 glyphs: Vec::with_capacity(run.glyph_count().try_into().unwrap_or(0)),
506 });
507 &mut runs.last_mut().unwrap().glyphs
508 }
509 };
510 for ((&glyph_id, position), &glyph_utf16_ix) in run
511 .glyphs()
512 .iter()
513 .zip(run.positions().iter())
514 .zip(run.string_indices().iter())
515 {
516 let mut glyph_utf16_ix = usize::try_from(glyph_utf16_ix).unwrap();
517 let r = self
518 .zwnjs_scratch_space
519 .binary_search_by(|&(_, it)| it.cmp(&glyph_utf16_ix));
520 match r {
521 // this glyph is a ZWNJ, skip it
522 Ok(_) => continue,
523 // adjust the index to account for the ZWNJs we've inserted
524 Err(idx) => glyph_utf16_ix -= idx * ZWNJ_SIZE_16,
525 }
526 if ix_converter.utf16_ix > glyph_utf16_ix {
527 // We cannot reuse current index converter, as it can only seek forward. Restart the search.
528 ix_converter = StringIndexConverter::new(text);
529 }
530 ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
531 glyphs.push(ShapedGlyph {
532 id: GlyphId(glyph_id as u32),
533 position: point(position.x as f32, position.y as f32).map(px),
534 index: ix_converter.utf8_ix,
535 is_emoji: self.is_emoji(font_id),
536 });
537 }
538 }
539 let typographic_bounds = line.get_typographic_bounds();
540 LineLayout {
541 runs,
542 font_size,
543 width: typographic_bounds.width.into(),
544 ascent: max_ascent.into(),
545 descent: max_descent.into(),
546 len: text.len(),
547 }
548 }
549}
550
551#[derive(Clone)]
552struct StringIndexConverter<'a> {
553 text: &'a str,
554 utf8_ix: usize,
555 utf16_ix: usize,
556}
557
558impl<'a> StringIndexConverter<'a> {
559 fn new(text: &'a str) -> Self {
560 Self {
561 text,
562 utf8_ix: 0,
563 utf16_ix: 0,
564 }
565 }
566
567 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
568 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
569 if self.utf8_ix + ix >= utf8_target {
570 self.utf8_ix += ix;
571 return;
572 }
573 self.utf16_ix += c.len_utf16();
574 }
575 self.utf8_ix = self.text.len();
576 }
577
578 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
579 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
580 if self.utf16_ix >= utf16_target {
581 self.utf8_ix += ix;
582 return;
583 }
584 self.utf16_ix += c.len_utf16();
585 }
586 self.utf8_ix = self.text.len();
587 }
588}
589
590impl From<Metrics> for FontMetrics {
591 fn from(metrics: Metrics) -> Self {
592 FontMetrics {
593 units_per_em: metrics.units_per_em,
594 ascent: metrics.ascent,
595 descent: metrics.descent,
596 line_gap: metrics.line_gap,
597 underline_position: metrics.underline_position,
598 underline_thickness: metrics.underline_thickness,
599 cap_height: metrics.cap_height,
600 x_height: metrics.x_height,
601 bounding_box: metrics.bounding_box.into(),
602 }
603 }
604}
605
606impl From<RectF> for Bounds<f32> {
607 fn from(rect: RectF) -> Self {
608 Bounds {
609 origin: point(rect.origin_x(), rect.origin_y()),
610 size: size(rect.width(), rect.height()),
611 }
612 }
613}
614
615impl From<RectI> for Bounds<DevicePixels> {
616 fn from(rect: RectI) -> Self {
617 Bounds {
618 origin: point(DevicePixels(rect.origin_x()), DevicePixels(rect.origin_y())),
619 size: size(DevicePixels(rect.width()), DevicePixels(rect.height())),
620 }
621 }
622}
623
624impl From<Vector2I> for Size<DevicePixels> {
625 fn from(value: Vector2I) -> Self {
626 size(value.x().into(), value.y().into())
627 }
628}
629
630impl From<RectI> for Bounds<i32> {
631 fn from(rect: RectI) -> Self {
632 Bounds {
633 origin: point(rect.origin_x(), rect.origin_y()),
634 size: size(rect.width(), rect.height()),
635 }
636 }
637}
638
639impl From<Point<u32>> for Vector2I {
640 fn from(size: Point<u32>) -> Self {
641 Vector2I::new(size.x as i32, size.y as i32)
642 }
643}
644
645impl From<Vector2F> for Size<f32> {
646 fn from(vec: Vector2F) -> Self {
647 size(vec.x(), vec.y())
648 }
649}
650
651impl From<FontWeight> for FontkitWeight {
652 fn from(value: FontWeight) -> Self {
653 FontkitWeight(value.0)
654 }
655}
656
657impl From<FontStyle> for FontkitStyle {
658 fn from(style: FontStyle) -> Self {
659 match style {
660 FontStyle::Normal => FontkitStyle::Normal,
661 FontStyle::Italic => FontkitStyle::Italic,
662 FontStyle::Oblique => FontkitStyle::Oblique,
663 }
664 }
665}
666
667// Some fonts may have no attributes despite `core_text` requiring them (and panicking).
668// This is the same version as `core_text` has without `expect` calls.
669mod lenient_font_attributes {
670 use core_foundation::{
671 base::{CFRetain, CFType, TCFType},
672 string::{CFString, CFStringRef},
673 };
674 use core_text::font_descriptor::{
675 CTFontDescriptor, CTFontDescriptorCopyAttribute, kCTFontFamilyNameAttribute,
676 };
677
678 pub fn family_name(descriptor: &CTFontDescriptor) -> Option<String> {
679 unsafe { get_string_attribute(descriptor, kCTFontFamilyNameAttribute) }
680 }
681
682 fn get_string_attribute(
683 descriptor: &CTFontDescriptor,
684 attribute: CFStringRef,
685 ) -> Option<String> {
686 unsafe {
687 let value = CTFontDescriptorCopyAttribute(descriptor.as_concrete_TypeRef(), attribute);
688 if value.is_null() {
689 return None;
690 }
691
692 let value = CFType::wrap_under_create_rule(value);
693 assert!(value.instance_of::<CFString>());
694 let s = wrap_under_get_rule(value.as_CFTypeRef() as CFStringRef);
695 Some(s.to_string())
696 }
697 }
698
699 unsafe fn wrap_under_get_rule(reference: CFStringRef) -> CFString {
700 unsafe {
701 assert!(!reference.is_null(), "Attempted to create a NULL object.");
702 let reference = CFRetain(reference as *const ::std::os::raw::c_void) as CFStringRef;
703 TCFType::wrap_under_create_rule(reference)
704 }
705 }
706}
707
708#[cfg(test)]
709mod tests {
710 use crate::{FontRun, GlyphId, MacTextSystem, PlatformTextSystem, font, px};
711
712 #[test]
713 fn test_layout_line_bom_char() {
714 let fonts = MacTextSystem::new();
715 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
716 let line = "\u{feff}";
717 let mut style = FontRun {
718 font_id,
719 len: line.len(),
720 };
721
722 let layout = fonts.layout_line(line, px(16.), &[style]);
723 assert_eq!(layout.len, line.len());
724 assert!(layout.runs.is_empty());
725
726 let line = "a\u{feff}b";
727 style.len = line.len();
728 let layout = fonts.layout_line(line, px(16.), &[style]);
729 assert_eq!(layout.len, line.len());
730 assert_eq!(layout.runs.len(), 1);
731 assert_eq!(layout.runs[0].glyphs.len(), 2);
732 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
733 // There's no glyph for \u{feff}
734 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
735 }
736
737 #[test]
738 fn test_layout_line_zwnj_insertion() {
739 let fonts = MacTextSystem::new();
740 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
741
742 let text = "hello world";
743 let font_runs = &[
744 FontRun { font_id, len: 5 }, // "hello"
745 FontRun { font_id, len: 6 }, // " world"
746 ];
747
748 let layout = fonts.layout_line(text, px(16.), font_runs);
749 assert_eq!(layout.len, text.len());
750
751 for run in &layout.runs {
752 for glyph in &run.glyphs {
753 assert!(
754 glyph.index < text.len(),
755 "Glyph index {} is out of bounds for text length {}",
756 glyph.index,
757 text.len()
758 );
759 }
760 }
761
762 // Test with different font runs - should not insert ZWNJ
763 let font_id2 = fonts.font_id(&font("Times")).unwrap_or(font_id);
764 let font_runs_different = &[
765 FontRun { font_id, len: 5 }, // "hello"
766 // " world"
767 FontRun {
768 font_id: font_id2,
769 len: 6,
770 },
771 ];
772
773 let layout2 = fonts.layout_line(text, px(16.), font_runs_different);
774 assert_eq!(layout2.len, text.len());
775
776 for run in &layout2.runs {
777 for glyph in &run.glyphs {
778 assert!(
779 glyph.index < text.len(),
780 "Glyph index {} is out of bounds for text length {}",
781 glyph.index,
782 text.len()
783 );
784 }
785 }
786 }
787
788 #[test]
789 fn test_layout_line_zwnj_edge_cases() {
790 let fonts = MacTextSystem::new();
791 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
792
793 let text = "hello";
794 let font_runs = &[FontRun { font_id, len: 5 }];
795 let layout = fonts.layout_line(text, px(16.), font_runs);
796 assert_eq!(layout.len, text.len());
797
798 let text = "abc";
799 let font_runs = &[
800 FontRun { font_id, len: 1 }, // "a"
801 FontRun { font_id, len: 1 }, // "b"
802 FontRun { font_id, len: 1 }, // "c"
803 ];
804 let layout = fonts.layout_line(text, px(16.), font_runs);
805 assert_eq!(layout.len, text.len());
806
807 for run in &layout.runs {
808 for glyph in &run.glyphs {
809 assert!(
810 glyph.index < text.len(),
811 "Glyph index {} is out of bounds for text length {}",
812 glyph.index,
813 text.len()
814 );
815 }
816 }
817
818 // Test with empty text
819 let text = "";
820 let font_runs = &[];
821 let layout = fonts.layout_line(text, px(16.), font_runs);
822 assert_eq!(layout.len, 0);
823 assert!(layout.runs.is_empty());
824 }
825}