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 /// UTF-16 indices of ZWNJS
71 zwnjs_scratch_space: Vec<usize>,
72}
73
74impl MacTextSystem {
75 pub(crate) fn new() -> Self {
76 Self(RwLock::new(MacTextSystemState {
77 memory_source: MemSource::empty(),
78 system_source: SystemSource::new(),
79 fonts: Vec::new(),
80 font_selections: HashMap::default(),
81 font_ids_by_postscript_name: HashMap::default(),
82 font_ids_by_font_key: HashMap::default(),
83 postscript_names_by_font_id: HashMap::default(),
84 zwnjs_scratch_space: Vec::new(),
85 }))
86 }
87}
88
89impl Default for MacTextSystem {
90 fn default() -> Self {
91 Self::new()
92 }
93}
94
95impl PlatformTextSystem for MacTextSystem {
96 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
97 self.0.write().add_fonts(fonts)
98 }
99
100 fn all_font_names(&self) -> Vec<String> {
101 let mut names = Vec::new();
102 let collection = core_text::font_collection::create_for_all_families();
103 let Some(descriptors) = collection.get_descriptors() else {
104 return names;
105 };
106 for descriptor in descriptors.into_iter() {
107 names.extend(lenient_font_attributes::family_name(&descriptor));
108 }
109 if let Ok(fonts_in_memory) = self.0.read().memory_source.all_families() {
110 names.extend(fonts_in_memory);
111 }
112 names
113 }
114
115 fn font_id(&self, font: &Font) -> Result<FontId> {
116 let lock = self.0.upgradable_read();
117 if let Some(font_id) = lock.font_selections.get(font) {
118 Ok(*font_id)
119 } else {
120 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
121 let font_key = FontKey {
122 font_family: font.family.clone(),
123 font_features: font.features.clone(),
124 font_fallbacks: font.fallbacks.clone(),
125 };
126 let candidates = if let Some(font_ids) = lock.font_ids_by_font_key.get(&font_key) {
127 font_ids.as_slice()
128 } else {
129 let font_ids =
130 lock.load_family(&font.family, &font.features, font.fallbacks.as_ref())?;
131 lock.font_ids_by_font_key.insert(font_key.clone(), font_ids);
132 lock.font_ids_by_font_key[&font_key].as_ref()
133 };
134
135 let candidate_properties = candidates
136 .iter()
137 .map(|font_id| lock.fonts[font_id.0].properties())
138 .collect::<SmallVec<[_; 4]>>();
139
140 let ix = font_kit::matching::find_best_match(
141 &candidate_properties,
142 &font_kit::properties::Properties {
143 style: font.style.into(),
144 weight: font.weight.into(),
145 stretch: Default::default(),
146 },
147 )?;
148
149 let font_id = candidates[ix];
150 lock.font_selections.insert(font.clone(), font_id);
151 Ok(font_id)
152 }
153 }
154
155 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
156 self.0.read().fonts[font_id.0].metrics().into()
157 }
158
159 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
160 Ok(self.0.read().fonts[font_id.0]
161 .typographic_bounds(glyph_id.0)?
162 .into())
163 }
164
165 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
166 self.0.read().advance(font_id, glyph_id)
167 }
168
169 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
170 self.0.read().glyph_for_char(font_id, ch)
171 }
172
173 fn glyph_raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
174 self.0.read().raster_bounds(params)
175 }
176
177 fn rasterize_glyph(
178 &self,
179 glyph_id: &RenderGlyphParams,
180 raster_bounds: Bounds<DevicePixels>,
181 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
182 self.0.read().rasterize_glyph(glyph_id, raster_bounds)
183 }
184
185 fn layout_line(&self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
186 self.0.write().layout_line(text, font_size, font_runs)
187 }
188}
189
190impl MacTextSystemState {
191 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
192 let fonts = fonts
193 .into_iter()
194 .map(|bytes| match bytes {
195 Cow::Borrowed(embedded_font) => {
196 let data_provider = unsafe {
197 core_graphics::data_provider::CGDataProvider::from_slice(embedded_font)
198 };
199 let font = core_graphics::font::CGFont::from_data_provider(data_provider)
200 .map_err(|()| anyhow!("Could not load an embedded font."))?;
201 let font = font_kit::loaders::core_text::Font::from_core_graphics_font(font);
202 Ok(Handle::from_native(&font))
203 }
204 Cow::Owned(bytes) => Ok(Handle::from_memory(Arc::new(bytes), 0)),
205 })
206 .collect::<Result<Vec<_>>>()?;
207 self.memory_source.add_fonts(fonts.into_iter())?;
208 Ok(())
209 }
210
211 fn load_family(
212 &mut self,
213 name: &str,
214 features: &FontFeatures,
215 fallbacks: Option<&FontFallbacks>,
216 ) -> Result<SmallVec<[FontId; 4]>> {
217 let name = crate::text_system::font_name_with_fallbacks(name, ".AppleSystemUIFont");
218
219 let mut font_ids = SmallVec::new();
220 let family = self
221 .memory_source
222 .select_family_by_name(name)
223 .or_else(|_| self.system_source.select_family_by_name(name))?;
224 for font in family.fonts() {
225 let mut font = font.load()?;
226
227 apply_features_and_fallbacks(&mut font, features, fallbacks)?;
228 // This block contains a precautionary fix to guard against loading fonts
229 // that might cause panics due to `.unwrap()`s up the chain.
230 {
231 // We use the 'm' character for text measurements in various spots
232 // (e.g., the editor). However, at time of writing some of those usages
233 // will panic if the font has no 'm' glyph.
234 //
235 // Therefore, we check up front that the font has the necessary glyph.
236 let has_m_glyph = font.glyph_for_char('m').is_some();
237
238 // HACK: The 'Segoe Fluent Icons' font does not have an 'm' glyph,
239 // but we need to be able to load it for rendering Windows icons in
240 // the Storybook (on macOS).
241 let is_segoe_fluent_icons = font.full_name() == "Segoe Fluent Icons";
242
243 if !has_m_glyph && !is_segoe_fluent_icons {
244 // I spent far too long trying to track down why a font missing the 'm'
245 // character wasn't loading. This log statement will hopefully save
246 // someone else from suffering the same fate.
247 log::warn!(
248 "font '{}' has no 'm' character and was not loaded",
249 font.full_name()
250 );
251 continue;
252 }
253 }
254
255 // We've seen a number of panics in production caused by calling font.properties()
256 // which unwraps a downcast to CFNumber. This is an attempt to avoid the panic,
257 // and to try and identify the incalcitrant font.
258 let traits = font.native_font().all_traits();
259 if unsafe {
260 !(traits
261 .get(kCTFontSymbolicTrait)
262 .downcast::<CFNumber>()
263 .is_some()
264 && traits
265 .get(kCTFontWidthTrait)
266 .downcast::<CFNumber>()
267 .is_some()
268 && traits
269 .get(kCTFontWeightTrait)
270 .downcast::<CFNumber>()
271 .is_some()
272 && traits
273 .get(kCTFontSlantTrait)
274 .downcast::<CFNumber>()
275 .is_some())
276 } {
277 log::error!(
278 "Failed to read traits for font {:?}",
279 font.postscript_name().unwrap()
280 );
281 continue;
282 }
283
284 let font_id = FontId(self.fonts.len());
285 font_ids.push(font_id);
286 let postscript_name = font.postscript_name().unwrap();
287 self.font_ids_by_postscript_name
288 .insert(postscript_name.clone(), font_id);
289 self.postscript_names_by_font_id
290 .insert(font_id, postscript_name);
291 self.fonts.push(font);
292 }
293 Ok(font_ids)
294 }
295
296 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
297 Ok(self.fonts[font_id.0].advance(glyph_id.0)?.into())
298 }
299
300 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
301 self.fonts[font_id.0].glyph_for_char(ch).map(GlyphId)
302 }
303
304 fn id_for_native_font(&mut self, requested_font: CTFont) -> FontId {
305 let postscript_name = requested_font.postscript_name();
306 if let Some(font_id) = self.font_ids_by_postscript_name.get(&postscript_name) {
307 *font_id
308 } else {
309 let font_id = FontId(self.fonts.len());
310 self.font_ids_by_postscript_name
311 .insert(postscript_name.clone(), font_id);
312 self.postscript_names_by_font_id
313 .insert(font_id, postscript_name);
314 self.fonts
315 .push(font_kit::font::Font::from_core_graphics_font(
316 requested_font.copy_to_CGFont(),
317 ));
318 font_id
319 }
320 }
321
322 fn is_emoji(&self, font_id: FontId) -> bool {
323 self.postscript_names_by_font_id
324 .get(&font_id)
325 .is_some_and(|postscript_name| {
326 postscript_name == "AppleColorEmoji" || postscript_name == ".AppleColorEmojiUI"
327 })
328 }
329
330 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
331 let font = &self.fonts[params.font_id.0];
332 let scale = Transform2F::from_scale(params.scale_factor);
333 Ok(font
334 .raster_bounds(
335 params.glyph_id.0,
336 params.font_size.into(),
337 scale,
338 HintingOptions::None,
339 font_kit::canvas::RasterizationOptions::GrayscaleAa,
340 )?
341 .into())
342 }
343
344 fn rasterize_glyph(
345 &self,
346 params: &RenderGlyphParams,
347 glyph_bounds: Bounds<DevicePixels>,
348 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
349 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
350 anyhow::bail!("glyph bounds are empty");
351 } else {
352 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
353 let mut bitmap_size = glyph_bounds.size;
354 if params.subpixel_variant.x > 0 {
355 bitmap_size.width += DevicePixels(1);
356 }
357 if params.subpixel_variant.y > 0 {
358 bitmap_size.height += DevicePixels(1);
359 }
360 let bitmap_size = bitmap_size;
361
362 let mut bytes;
363 let cx;
364 if params.is_emoji {
365 bytes = vec![0; bitmap_size.width.0 as usize * 4 * bitmap_size.height.0 as usize];
366 cx = CGContext::create_bitmap_context(
367 Some(bytes.as_mut_ptr() as *mut _),
368 bitmap_size.width.0 as usize,
369 bitmap_size.height.0 as usize,
370 8,
371 bitmap_size.width.0 as usize * 4,
372 &CGColorSpace::create_device_rgb(),
373 kCGImageAlphaPremultipliedLast,
374 );
375 } else {
376 bytes = vec![0; bitmap_size.width.0 as usize * bitmap_size.height.0 as usize];
377 cx = CGContext::create_bitmap_context(
378 Some(bytes.as_mut_ptr() as *mut _),
379 bitmap_size.width.0 as usize,
380 bitmap_size.height.0 as usize,
381 8,
382 bitmap_size.width.0 as usize,
383 &CGColorSpace::create_device_gray(),
384 kCGImageAlphaOnly,
385 );
386 }
387
388 // Move the origin to bottom left and account for scaling, this
389 // makes drawing text consistent with the font-kit's raster_bounds.
390 cx.translate(
391 -glyph_bounds.origin.x.0 as CGFloat,
392 (glyph_bounds.origin.y.0 + glyph_bounds.size.height.0) as CGFloat,
393 );
394 cx.scale(
395 params.scale_factor as CGFloat,
396 params.scale_factor as CGFloat,
397 );
398
399 let subpixel_shift = params
400 .subpixel_variant
401 .map(|v| v as f32 / SUBPIXEL_VARIANTS_X as f32);
402 cx.set_text_drawing_mode(CGTextDrawingMode::CGTextFill);
403 cx.set_gray_fill_color(0.0, 1.0);
404 cx.set_allows_antialiasing(true);
405 cx.set_should_antialias(true);
406 cx.set_allows_font_subpixel_positioning(true);
407 cx.set_should_subpixel_position_fonts(true);
408 cx.set_allows_font_subpixel_quantization(false);
409 cx.set_should_subpixel_quantize_fonts(false);
410 self.fonts[params.font_id.0]
411 .native_font()
412 .clone_with_font_size(f32::from(params.font_size) as CGFloat)
413 .draw_glyphs(
414 &[params.glyph_id.0 as CGGlyph],
415 &[CGPoint::new(
416 (subpixel_shift.x / params.scale_factor) as CGFloat,
417 (subpixel_shift.y / params.scale_factor) as CGFloat,
418 )],
419 cx,
420 );
421
422 if params.is_emoji {
423 // Convert from RGBA with premultiplied alpha to BGRA with straight alpha.
424 for pixel in bytes.chunks_exact_mut(4) {
425 swap_rgba_pa_to_bgra(pixel);
426 }
427 }
428
429 Ok((bitmap_size, bytes))
430 }
431 }
432
433 fn layout_line(&mut self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
434 const ZWNJ: char = '\u{200C}';
435 const ZWNJ_STR: &str = "\u{200C}";
436 const ZWNJ_SIZE_16: usize = ZWNJ.len_utf16();
437
438 self.zwnjs_scratch_space.clear();
439 // Construct the attributed string, converting UTF8 ranges to UTF16 ranges.
440 let mut string = CFMutableAttributedString::new();
441 let mut max_ascent = 0.0f32;
442 let mut max_descent = 0.0f32;
443
444 {
445 let mut ix_converter = StringIndexConverter::new(&text);
446 let mut last_font_run = None;
447 for run in font_runs {
448 let text = &text[ix_converter.utf8_ix..][..run.len];
449 // if the fonts are the same, we need to disconnect the text with a ZWNJ
450 // to prevent core text from forming ligatures between them
451 let needs_zwnj = last_font_run.replace(run.font_id) == Some(run.font_id);
452
453 let n_zwnjs = self.zwnjs_scratch_space.len(); // from previous loop
454 let utf16_start = string.char_len(); // insert at end of string
455 ix_converter.advance_to_utf8_ix(ix_converter.utf8_ix + run.len);
456
457 // note: replace_str may silently ignore codepoints it dislikes (e.g., BOM at start of string)
458 string.replace_str(&CFString::new(text), CFRange::init(utf16_start, 0));
459 if needs_zwnj {
460 let zwnjs_pos = string.char_len();
461 self.zwnjs_scratch_space.push(zwnjs_pos as usize);
462 string.replace_str(
463 &CFString::from_static_string(ZWNJ_STR),
464 CFRange::init(zwnjs_pos, 0),
465 );
466 }
467 let utf16_end = string.char_len();
468
469 let cf_range = CFRange::init(utf16_start, utf16_end - utf16_start);
470 let font = &self.fonts[run.font_id.0];
471
472 let font_metrics = font.metrics();
473 let font_scale = font_size.0 / font_metrics.units_per_em as f32;
474 max_ascent = max_ascent.max(font_metrics.ascent * font_scale);
475 max_descent = max_descent.max(-font_metrics.descent * font_scale);
476
477 unsafe {
478 string.set_attribute(
479 cf_range,
480 kCTFontAttributeName,
481 &font.native_font().clone_with_font_size(font_size.into()),
482 );
483 }
484 }
485 }
486 // Retrieve the glyphs from the shaped line, converting UTF16 offsets to UTF8 offsets.
487 let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
488 let glyph_runs = line.glyph_runs();
489 let mut runs = <Vec<ShapedRun>>::with_capacity(glyph_runs.len() as usize);
490 let mut ix_converter = StringIndexConverter::new(text);
491 for run in glyph_runs.into_iter() {
492 let attributes = run.attributes().unwrap();
493 let font = unsafe {
494 attributes
495 .get(kCTFontAttributeName)
496 .downcast::<CTFont>()
497 .unwrap()
498 };
499 let font_id = self.id_for_native_font(font);
500
501 let mut glyphs = match runs.last_mut() {
502 Some(run) if run.font_id == font_id => &mut run.glyphs,
503 _ => {
504 runs.push(ShapedRun {
505 font_id,
506 glyphs: Vec::with_capacity(run.glyph_count().try_into().unwrap_or(0)),
507 });
508 &mut runs.last_mut().unwrap().glyphs
509 }
510 };
511 for ((&glyph_id, position), &glyph_utf16_ix) in run
512 .glyphs()
513 .iter()
514 .zip(run.positions().iter())
515 .zip(run.string_indices().iter())
516 {
517 let mut glyph_utf16_ix = usize::try_from(glyph_utf16_ix).unwrap();
518 let r = self
519 .zwnjs_scratch_space
520 .binary_search_by(|&it| it.cmp(&glyph_utf16_ix));
521 match r {
522 // this glyph is a ZWNJ, skip it
523 Ok(_) => continue,
524 // adjust the index to account for the ZWNJs we've inserted
525 Err(idx) => glyph_utf16_ix -= idx * ZWNJ_SIZE_16,
526 }
527 if ix_converter.utf16_ix > glyph_utf16_ix {
528 // We cannot reuse current index converter, as it can only seek forward. Restart the search.
529 ix_converter = StringIndexConverter::new(text);
530 }
531 ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
532 glyphs.push(ShapedGlyph {
533 id: GlyphId(glyph_id as u32),
534 position: point(position.x as f32, position.y as f32).map(px),
535 index: ix_converter.utf8_ix,
536 is_emoji: self.is_emoji(font_id),
537 });
538 }
539 }
540 let typographic_bounds = line.get_typographic_bounds();
541 LineLayout {
542 runs,
543 font_size,
544 width: typographic_bounds.width.into(),
545 ascent: max_ascent.into(),
546 descent: max_descent.into(),
547 len: text.len(),
548 }
549 }
550}
551
552#[derive(Debug, Clone)]
553struct StringIndexConverter<'a> {
554 text: &'a str,
555 /// Index in UTF-8 bytes
556 utf8_ix: usize,
557 /// Index in UTF-16 code units
558 utf16_ix: usize,
559}
560
561impl<'a> StringIndexConverter<'a> {
562 fn new(text: &'a str) -> Self {
563 Self {
564 text,
565 utf8_ix: 0,
566 utf16_ix: 0,
567 }
568 }
569
570 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
571 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
572 if self.utf8_ix + ix >= utf8_target {
573 self.utf8_ix += ix;
574 return;
575 }
576 self.utf16_ix += c.len_utf16();
577 }
578 self.utf8_ix = self.text.len();
579 }
580
581 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
582 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
583 if self.utf16_ix >= utf16_target {
584 self.utf8_ix += ix;
585 return;
586 }
587 self.utf16_ix += c.len_utf16();
588 }
589 self.utf8_ix = self.text.len();
590 }
591}
592
593impl From<Metrics> for FontMetrics {
594 fn from(metrics: Metrics) -> Self {
595 FontMetrics {
596 units_per_em: metrics.units_per_em,
597 ascent: metrics.ascent,
598 descent: metrics.descent,
599 line_gap: metrics.line_gap,
600 underline_position: metrics.underline_position,
601 underline_thickness: metrics.underline_thickness,
602 cap_height: metrics.cap_height,
603 x_height: metrics.x_height,
604 bounding_box: metrics.bounding_box.into(),
605 }
606 }
607}
608
609impl From<RectF> for Bounds<f32> {
610 fn from(rect: RectF) -> Self {
611 Bounds {
612 origin: point(rect.origin_x(), rect.origin_y()),
613 size: size(rect.width(), rect.height()),
614 }
615 }
616}
617
618impl From<RectI> for Bounds<DevicePixels> {
619 fn from(rect: RectI) -> Self {
620 Bounds {
621 origin: point(DevicePixels(rect.origin_x()), DevicePixels(rect.origin_y())),
622 size: size(DevicePixels(rect.width()), DevicePixels(rect.height())),
623 }
624 }
625}
626
627impl From<Vector2I> for Size<DevicePixels> {
628 fn from(value: Vector2I) -> Self {
629 size(value.x().into(), value.y().into())
630 }
631}
632
633impl From<RectI> for Bounds<i32> {
634 fn from(rect: RectI) -> Self {
635 Bounds {
636 origin: point(rect.origin_x(), rect.origin_y()),
637 size: size(rect.width(), rect.height()),
638 }
639 }
640}
641
642impl From<Point<u32>> for Vector2I {
643 fn from(size: Point<u32>) -> Self {
644 Vector2I::new(size.x as i32, size.y as i32)
645 }
646}
647
648impl From<Vector2F> for Size<f32> {
649 fn from(vec: Vector2F) -> Self {
650 size(vec.x(), vec.y())
651 }
652}
653
654impl From<FontWeight> for FontkitWeight {
655 fn from(value: FontWeight) -> Self {
656 FontkitWeight(value.0)
657 }
658}
659
660impl From<FontStyle> for FontkitStyle {
661 fn from(style: FontStyle) -> Self {
662 match style {
663 FontStyle::Normal => FontkitStyle::Normal,
664 FontStyle::Italic => FontkitStyle::Italic,
665 FontStyle::Oblique => FontkitStyle::Oblique,
666 }
667 }
668}
669
670// Some fonts may have no attributes despite `core_text` requiring them (and panicking).
671// This is the same version as `core_text` has without `expect` calls.
672mod lenient_font_attributes {
673 use core_foundation::{
674 base::{CFRetain, CFType, TCFType},
675 string::{CFString, CFStringRef},
676 };
677 use core_text::font_descriptor::{
678 CTFontDescriptor, CTFontDescriptorCopyAttribute, kCTFontFamilyNameAttribute,
679 };
680
681 pub fn family_name(descriptor: &CTFontDescriptor) -> Option<String> {
682 unsafe { get_string_attribute(descriptor, kCTFontFamilyNameAttribute) }
683 }
684
685 fn get_string_attribute(
686 descriptor: &CTFontDescriptor,
687 attribute: CFStringRef,
688 ) -> Option<String> {
689 unsafe {
690 let value = CTFontDescriptorCopyAttribute(descriptor.as_concrete_TypeRef(), attribute);
691 if value.is_null() {
692 return None;
693 }
694
695 let value = CFType::wrap_under_create_rule(value);
696 assert!(value.instance_of::<CFString>());
697 let s = wrap_under_get_rule(value.as_CFTypeRef() as CFStringRef);
698 Some(s.to_string())
699 }
700 }
701
702 unsafe fn wrap_under_get_rule(reference: CFStringRef) -> CFString {
703 unsafe {
704 assert!(!reference.is_null(), "Attempted to create a NULL object.");
705 let reference = CFRetain(reference as *const ::std::os::raw::c_void) as CFStringRef;
706 TCFType::wrap_under_create_rule(reference)
707 }
708 }
709}
710
711#[cfg(test)]
712mod tests {
713 use crate::{FontRun, GlyphId, MacTextSystem, PlatformTextSystem, font, px};
714
715 #[test]
716 fn test_layout_line_bom_char() {
717 let fonts = MacTextSystem::new();
718 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
719 let line = "\u{feff}";
720 let mut style = FontRun {
721 font_id,
722 len: line.len(),
723 };
724
725 let layout = fonts.layout_line(line, px(16.), &[style]);
726 assert_eq!(layout.len, line.len());
727 assert!(layout.runs.is_empty());
728
729 let line = "a\u{feff}b";
730 style.len = line.len();
731 let layout = fonts.layout_line(line, px(16.), &[style]);
732 assert_eq!(layout.len, line.len());
733 assert_eq!(layout.runs.len(), 1);
734 assert_eq!(layout.runs[0].glyphs.len(), 2);
735 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
736 // There's no glyph for \u{feff}
737 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
738
739 let line = "\u{feff}ab";
740 let font_runs = &[
741 FontRun {
742 len: "\u{feff}".len(),
743 font_id,
744 },
745 FontRun {
746 len: "ab".len(),
747 font_id,
748 },
749 ];
750 let layout = fonts.layout_line(line, px(16.), font_runs);
751 assert_eq!(layout.len, line.len());
752 assert_eq!(layout.runs.len(), 1);
753 assert_eq!(layout.runs[0].glyphs.len(), 2);
754 // There's no glyph for \u{feff}
755 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
756 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
757 }
758
759 #[test]
760 fn test_layout_line_zwnj_insertion() {
761 let fonts = MacTextSystem::new();
762 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
763
764 let text = "hello world";
765 let font_runs = &[
766 FontRun { font_id, len: 5 }, // "hello"
767 FontRun { font_id, len: 6 }, // " world"
768 ];
769
770 let layout = fonts.layout_line(text, px(16.), font_runs);
771 assert_eq!(layout.len, text.len());
772
773 for run in &layout.runs {
774 for glyph in &run.glyphs {
775 assert!(
776 glyph.index < text.len(),
777 "Glyph index {} is out of bounds for text length {}",
778 glyph.index,
779 text.len()
780 );
781 }
782 }
783
784 // Test with different font runs - should not insert ZWNJ
785 let font_id2 = fonts.font_id(&font("Times")).unwrap_or(font_id);
786 let font_runs_different = &[
787 FontRun { font_id, len: 5 }, // "hello"
788 // " world"
789 FontRun {
790 font_id: font_id2,
791 len: 6,
792 },
793 ];
794
795 let layout2 = fonts.layout_line(text, px(16.), font_runs_different);
796 assert_eq!(layout2.len, text.len());
797
798 for run in &layout2.runs {
799 for glyph in &run.glyphs {
800 assert!(
801 glyph.index < text.len(),
802 "Glyph index {} is out of bounds for text length {}",
803 glyph.index,
804 text.len()
805 );
806 }
807 }
808 }
809
810 #[test]
811 fn test_layout_line_zwnj_edge_cases() {
812 let fonts = MacTextSystem::new();
813 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
814
815 let text = "hello";
816 let font_runs = &[FontRun { font_id, len: 5 }];
817 let layout = fonts.layout_line(text, px(16.), font_runs);
818 assert_eq!(layout.len, text.len());
819
820 let text = "abc";
821 let font_runs = &[
822 FontRun { font_id, len: 1 }, // "a"
823 FontRun { font_id, len: 1 }, // "b"
824 FontRun { font_id, len: 1 }, // "c"
825 ];
826 let layout = fonts.layout_line(text, px(16.), font_runs);
827 assert_eq!(layout.len, text.len());
828
829 for run in &layout.runs {
830 for glyph in &run.glyphs {
831 assert!(
832 glyph.index < text.len(),
833 "Glyph index {} is out of bounds for text length {}",
834 glyph.index,
835 text.len()
836 );
837 }
838 }
839
840 // Test with empty text
841 let text = "";
842 let font_runs = &[];
843 let layout = fonts.layout_line(text, px(16.), font_runs);
844 assert_eq!(layout.len, 0);
845 assert!(layout.runs.is_empty());
846 }
847}