1use crate::{
2 point, px, size, Bounds, DevicePixels, Font, FontFeatures, FontId, FontMetrics, FontRun,
3 FontStyle, FontWeight, GlyphId, LineLayout, Pixels, PlatformTextSystem, Point,
4 RenderGlyphParams, Result, ShapedGlyph, ShapedRun, SharedString, Size, SUBPIXEL_VARIANTS,
5};
6use anyhow::anyhow;
7use cocoa::appkit::{CGFloat, CGPoint};
8use collections::{BTreeSet, HashMap};
9use core_foundation::{
10 array::CFIndex,
11 attributed_string::{CFAttributedStringRef, CFMutableAttributedString},
12 base::{CFRange, TCFType},
13 number::CFNumber,
14 string::CFString,
15};
16use core_graphics::{
17 base::{kCGImageAlphaPremultipliedLast, CGGlyph},
18 color_space::CGColorSpace,
19 context::CGContext,
20};
21use core_text::{
22 font::CTFont,
23 font_descriptor::{
24 kCTFontSlantTrait, kCTFontSymbolicTrait, kCTFontWeightTrait, kCTFontWidthTrait,
25 },
26 line::CTLine,
27 string_attributes::kCTFontAttributeName,
28};
29use font_kit::{
30 font::Font as FontKitFont,
31 handle::Handle,
32 hinting::HintingOptions,
33 metrics::Metrics,
34 properties::{Style as FontkitStyle, Weight as FontkitWeight},
35 source::SystemSource,
36 sources::mem::MemSource,
37};
38use parking_lot::{RwLock, RwLockUpgradableReadGuard};
39use pathfinder_geometry::{
40 rect::{RectF, RectI},
41 transform2d::Transform2F,
42 vector::{Vector2F, Vector2I},
43};
44use smallvec::SmallVec;
45use std::{borrow::Cow, char, cmp, convert::TryFrom, ffi::c_void, sync::Arc};
46
47use super::open_type;
48
49#[allow(non_upper_case_globals)]
50const kCGImageAlphaOnly: u32 = 7;
51
52pub(crate) struct MacTextSystem(RwLock<MacTextSystemState>);
53
54#[derive(Clone, PartialEq, Eq, Hash)]
55struct FontKey {
56 font_family: SharedString,
57 font_features: FontFeatures,
58}
59
60struct MacTextSystemState {
61 memory_source: MemSource,
62 system_source: SystemSource,
63 fonts: Vec<FontKitFont>,
64 font_selections: HashMap<Font, FontId>,
65 font_ids_by_postscript_name: HashMap<String, FontId>,
66 font_ids_by_font_key: HashMap<FontKey, SmallVec<[FontId; 4]>>,
67 postscript_names_by_font_id: HashMap<FontId, String>,
68}
69
70impl MacTextSystem {
71 pub(crate) fn new() -> Self {
72 Self(RwLock::new(MacTextSystemState {
73 memory_source: MemSource::empty(),
74 system_source: SystemSource::new(),
75 fonts: Vec::new(),
76 font_selections: HashMap::default(),
77 font_ids_by_postscript_name: HashMap::default(),
78 font_ids_by_font_key: HashMap::default(),
79 postscript_names_by_font_id: HashMap::default(),
80 }))
81 }
82}
83
84impl Default for MacTextSystem {
85 fn default() -> Self {
86 Self::new()
87 }
88}
89
90impl PlatformTextSystem for MacTextSystem {
91 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
92 self.0.write().add_fonts(fonts)
93 }
94
95 fn all_font_names(&self) -> Vec<String> {
96 let collection = core_text::font_collection::create_for_all_families();
97 let Some(descriptors) = collection.get_descriptors() else {
98 return Vec::new();
99 };
100 let mut names = BTreeSet::new();
101 for descriptor in descriptors.into_iter() {
102 names.extend(lenient_font_attributes::family_name(&descriptor));
103 }
104 if let Ok(fonts_in_memory) = self.0.read().memory_source.all_families() {
105 names.extend(fonts_in_memory);
106 }
107 names.into_iter().collect()
108 }
109
110 fn all_font_families(&self) -> Vec<String> {
111 self.0
112 .read()
113 .system_source
114 .all_families()
115 .expect("core text should never return an error")
116 }
117
118 fn font_id(&self, font: &Font) -> Result<FontId> {
119 let lock = self.0.upgradable_read();
120 if let Some(font_id) = lock.font_selections.get(font) {
121 Ok(*font_id)
122 } else {
123 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
124 let font_key = FontKey {
125 font_family: font.family.clone(),
126 font_features: font.features,
127 };
128 let candidates = if let Some(font_ids) = lock.font_ids_by_font_key.get(&font_key) {
129 font_ids.as_slice()
130 } else {
131 let font_ids = lock.load_family(&font.family, font.features)?;
132 lock.font_ids_by_font_key.insert(font_key.clone(), font_ids);
133 lock.font_ids_by_font_key[&font_key].as_ref()
134 };
135
136 let candidate_properties = candidates
137 .iter()
138 .map(|font_id| lock.fonts[font_id.0].properties())
139 .collect::<SmallVec<[_; 4]>>();
140
141 let ix = font_kit::matching::find_best_match(
142 &candidate_properties,
143 &font_kit::properties::Properties {
144 style: font.style.into(),
145 weight: font.weight.into(),
146 stretch: Default::default(),
147 },
148 )?;
149
150 let font_id = candidates[ix];
151 lock.font_selections.insert(font.clone(), font_id);
152 Ok(font_id)
153 }
154 }
155
156 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
157 self.0.read().fonts[font_id.0].metrics().into()
158 }
159
160 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
161 Ok(self.0.read().fonts[font_id.0]
162 .typographic_bounds(glyph_id.0)?
163 .into())
164 }
165
166 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
167 self.0.read().advance(font_id, glyph_id)
168 }
169
170 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
171 self.0.read().glyph_for_char(font_id, ch)
172 }
173
174 fn glyph_raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
175 self.0.read().raster_bounds(params)
176 }
177
178 fn rasterize_glyph(
179 &self,
180 glyph_id: &RenderGlyphParams,
181 raster_bounds: Bounds<DevicePixels>,
182 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
183 self.0.read().rasterize_glyph(glyph_id, raster_bounds)
184 }
185
186 fn layout_line(&self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
187 self.0.write().layout_line(text, font_size, font_runs)
188 }
189
190 fn wrap_line(
191 &self,
192 text: &str,
193 font_id: FontId,
194 font_size: Pixels,
195 width: Pixels,
196 ) -> Vec<usize> {
197 self.0.read().wrap_line(text, font_id, font_size, width)
198 }
199}
200
201impl MacTextSystemState {
202 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
203 let fonts = fonts
204 .into_iter()
205 .map(|bytes| match bytes {
206 Cow::Borrowed(embedded_font) => {
207 let data_provider = unsafe {
208 core_graphics::data_provider::CGDataProvider::from_slice(embedded_font)
209 };
210 let font = core_graphics::font::CGFont::from_data_provider(data_provider)
211 .map_err(|_| anyhow!("Could not load an embedded font."))?;
212 let font = font_kit::loaders::core_text::Font::from_core_graphics_font(font);
213 Ok(Handle::from_native(&font))
214 }
215 Cow::Owned(bytes) => Ok(Handle::from_memory(Arc::new(bytes), 0)),
216 })
217 .collect::<Result<Vec<_>>>()?;
218 self.memory_source.add_fonts(fonts.into_iter())?;
219 Ok(())
220 }
221
222 fn load_family(
223 &mut self,
224 name: &SharedString,
225 features: FontFeatures,
226 ) -> Result<SmallVec<[FontId; 4]>> {
227 let mut font_ids = SmallVec::new();
228 let family = self
229 .memory_source
230 .select_family_by_name(name.as_ref())
231 .or_else(|_| self.system_source.select_family_by_name(name.as_ref()))?;
232 for font in family.fonts() {
233 let mut font = font.load()?;
234
235 open_type::apply_features(&mut font, features);
236
237 // This block contains a precautionary fix to guard against loading fonts
238 // that might cause panics due to `.unwrap()`s up the chain.
239 {
240 // We use the 'm' character for text measurements in various spots
241 // (e.g., the editor). However, at time of writing some of those usages
242 // will panic if the font has no 'm' glyph.
243 //
244 // Therefore, we check up front that the font has the necessary glyph.
245 let has_m_glyph = font.glyph_for_char('m').is_some();
246
247 // HACK: The 'Segoe Fluent Icons' font does not have an 'm' glyph,
248 // but we need to be able to load it for rendering Windows icons in
249 // the Storybook (on macOS).
250 let is_segoe_fluent_icons = font.full_name() == "Segoe Fluent Icons";
251
252 if !has_m_glyph && !is_segoe_fluent_icons {
253 // I spent far too long trying to track down why a font missing the 'm'
254 // character wasn't loading. This log statement will hopefully save
255 // someone else from suffering the same fate.
256 log::warn!(
257 "font '{}' has no 'm' character and was not loaded",
258 font.full_name()
259 );
260 continue;
261 }
262 }
263
264 // We've seen a number of panics in production caused by calling font.properties()
265 // which unwraps a downcast to CFNumber. This is an attempt to avoid the panic,
266 // and to try and identify the incalcitrant font.
267 let traits = font.native_font().all_traits();
268 if unsafe {
269 !(traits
270 .get(kCTFontSymbolicTrait)
271 .downcast::<CFNumber>()
272 .is_some()
273 && traits
274 .get(kCTFontWidthTrait)
275 .downcast::<CFNumber>()
276 .is_some()
277 && traits
278 .get(kCTFontWeightTrait)
279 .downcast::<CFNumber>()
280 .is_some()
281 && traits
282 .get(kCTFontSlantTrait)
283 .downcast::<CFNumber>()
284 .is_some())
285 } {
286 log::error!(
287 "Failed to read traits for font {:?}",
288 font.postscript_name().unwrap()
289 );
290 continue;
291 }
292
293 let font_id = FontId(self.fonts.len());
294 font_ids.push(font_id);
295 let postscript_name = font.postscript_name().unwrap();
296 self.font_ids_by_postscript_name
297 .insert(postscript_name.clone(), font_id);
298 self.postscript_names_by_font_id
299 .insert(font_id, postscript_name);
300 self.fonts.push(font);
301 }
302 Ok(font_ids)
303 }
304
305 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
306 Ok(self.fonts[font_id.0].advance(glyph_id.0)?.into())
307 }
308
309 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
310 self.fonts[font_id.0].glyph_for_char(ch).map(GlyphId)
311 }
312
313 fn id_for_native_font(&mut self, requested_font: CTFont) -> FontId {
314 let postscript_name = requested_font.postscript_name();
315 if let Some(font_id) = self.font_ids_by_postscript_name.get(&postscript_name) {
316 *font_id
317 } else {
318 let font_id = FontId(self.fonts.len());
319 self.font_ids_by_postscript_name
320 .insert(postscript_name.clone(), font_id);
321 self.postscript_names_by_font_id
322 .insert(font_id, postscript_name);
323 self.fonts
324 .push(font_kit::font::Font::from_core_graphics_font(
325 requested_font.copy_to_CGFont(),
326 ));
327 font_id
328 }
329 }
330
331 fn is_emoji(&self, font_id: FontId) -> bool {
332 self.postscript_names_by_font_id
333 .get(&font_id)
334 .map_or(false, |postscript_name| {
335 postscript_name == "AppleColorEmoji"
336 })
337 }
338
339 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
340 let font = &self.fonts[params.font_id.0];
341 let scale = Transform2F::from_scale(params.scale_factor);
342 Ok(font
343 .raster_bounds(
344 params.glyph_id.0,
345 params.font_size.into(),
346 scale,
347 HintingOptions::None,
348 font_kit::canvas::RasterizationOptions::GrayscaleAa,
349 )?
350 .into())
351 }
352
353 fn rasterize_glyph(
354 &self,
355 params: &RenderGlyphParams,
356 glyph_bounds: Bounds<DevicePixels>,
357 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
358 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
359 Err(anyhow!("glyph bounds are empty"))
360 } else {
361 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
362 let mut bitmap_size = glyph_bounds.size;
363 if params.subpixel_variant.x > 0 {
364 bitmap_size.width += DevicePixels(1);
365 }
366 if params.subpixel_variant.y > 0 {
367 bitmap_size.height += DevicePixels(1);
368 }
369 let bitmap_size = bitmap_size;
370
371 let mut bytes;
372 let cx;
373 if params.is_emoji {
374 bytes = vec![0; bitmap_size.width.0 as usize * 4 * bitmap_size.height.0 as usize];
375 cx = CGContext::create_bitmap_context(
376 Some(bytes.as_mut_ptr() as *mut _),
377 bitmap_size.width.0 as usize,
378 bitmap_size.height.0 as usize,
379 8,
380 bitmap_size.width.0 as usize * 4,
381 &CGColorSpace::create_device_rgb(),
382 kCGImageAlphaPremultipliedLast,
383 );
384 } else {
385 bytes = vec![0; bitmap_size.width.0 as usize * bitmap_size.height.0 as usize];
386 cx = CGContext::create_bitmap_context(
387 Some(bytes.as_mut_ptr() as *mut _),
388 bitmap_size.width.0 as usize,
389 bitmap_size.height.0 as usize,
390 8,
391 bitmap_size.width.0 as usize,
392 &CGColorSpace::create_device_gray(),
393 kCGImageAlphaOnly,
394 );
395 }
396
397 // Move the origin to bottom left and account for scaling, this
398 // makes drawing text consistent with the font-kit's raster_bounds.
399 cx.translate(
400 -glyph_bounds.origin.x.0 as CGFloat,
401 (glyph_bounds.origin.y.0 + glyph_bounds.size.height.0) as CGFloat,
402 );
403 cx.scale(
404 params.scale_factor as CGFloat,
405 params.scale_factor as CGFloat,
406 );
407
408 let subpixel_shift = params
409 .subpixel_variant
410 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
411 cx.set_allows_font_subpixel_positioning(true);
412 cx.set_should_subpixel_position_fonts(true);
413 cx.set_allows_font_subpixel_quantization(false);
414 cx.set_should_subpixel_quantize_fonts(false);
415 self.fonts[params.font_id.0]
416 .native_font()
417 .clone_with_font_size(f32::from(params.font_size) as CGFloat)
418 .draw_glyphs(
419 &[params.glyph_id.0 as CGGlyph],
420 &[CGPoint::new(
421 (subpixel_shift.x / params.scale_factor) as CGFloat,
422 (subpixel_shift.y / params.scale_factor) as CGFloat,
423 )],
424 cx,
425 );
426
427 if params.is_emoji {
428 // Convert from RGBA with premultiplied alpha to BGRA with straight alpha.
429 for pixel in bytes.chunks_exact_mut(4) {
430 pixel.swap(0, 2);
431 let a = pixel[3] as f32 / 255.;
432 pixel[0] = (pixel[0] as f32 / a) as u8;
433 pixel[1] = (pixel[1] as f32 / a) as u8;
434 pixel[2] = (pixel[2] as f32 / a) as u8;
435 }
436 }
437
438 Ok((bitmap_size, bytes))
439 }
440 }
441
442 fn layout_line(&mut self, text: &str, font_size: Pixels, font_runs: &[FontRun]) -> LineLayout {
443 // Construct the attributed string, converting UTF8 ranges to UTF16 ranges.
444 let mut string = CFMutableAttributedString::new();
445 {
446 string.replace_str(&CFString::new(text), CFRange::init(0, 0));
447 let utf16_line_len = string.char_len() as usize;
448
449 let mut ix_converter = StringIndexConverter::new(text);
450 for run in font_runs {
451 let utf8_end = ix_converter.utf8_ix + run.len;
452 let utf16_start = ix_converter.utf16_ix;
453
454 if utf16_start >= utf16_line_len {
455 break;
456 }
457
458 ix_converter.advance_to_utf8_ix(utf8_end);
459 let utf16_end = cmp::min(ix_converter.utf16_ix, utf16_line_len);
460
461 let cf_range =
462 CFRange::init(utf16_start as isize, (utf16_end - utf16_start) as isize);
463
464 let font: &FontKitFont = &self.fonts[run.font_id.0];
465 unsafe {
466 string.set_attribute(
467 cf_range,
468 kCTFontAttributeName,
469 &font.native_font().clone_with_font_size(font_size.into()),
470 );
471 }
472
473 if utf16_end == utf16_line_len {
474 break;
475 }
476 }
477 }
478
479 // Retrieve the glyphs from the shaped line, converting UTF16 offsets to UTF8 offsets.
480 let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
481
482 let mut runs = Vec::new();
483 for run in line.glyph_runs().into_iter() {
484 let attributes = run.attributes().unwrap();
485 let font = unsafe {
486 attributes
487 .get(kCTFontAttributeName)
488 .downcast::<CTFont>()
489 .unwrap()
490 };
491 let font_id = self.id_for_native_font(font);
492
493 let mut ix_converter = StringIndexConverter::new(text);
494 let mut glyphs = SmallVec::new();
495 for ((glyph_id, position), glyph_utf16_ix) in run
496 .glyphs()
497 .iter()
498 .zip(run.positions().iter())
499 .zip(run.string_indices().iter())
500 {
501 let glyph_utf16_ix = usize::try_from(*glyph_utf16_ix).unwrap();
502 ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
503 glyphs.push(ShapedGlyph {
504 id: GlyphId(*glyph_id as u32),
505 position: point(position.x as f32, position.y as f32).map(px),
506 index: ix_converter.utf8_ix,
507 is_emoji: self.is_emoji(font_id),
508 });
509 }
510
511 runs.push(ShapedRun { font_id, glyphs })
512 }
513
514 let typographic_bounds = line.get_typographic_bounds();
515 LineLayout {
516 runs,
517 font_size,
518 width: typographic_bounds.width.into(),
519 ascent: typographic_bounds.ascent.into(),
520 descent: typographic_bounds.descent.into(),
521 len: text.len(),
522 }
523 }
524
525 fn wrap_line(
526 &self,
527 text: &str,
528 font_id: FontId,
529 font_size: Pixels,
530 width: Pixels,
531 ) -> Vec<usize> {
532 let mut string = CFMutableAttributedString::new();
533 string.replace_str(&CFString::new(text), CFRange::init(0, 0));
534 let cf_range = CFRange::init(0, text.encode_utf16().count() as isize);
535 let font = &self.fonts[font_id.0];
536 unsafe {
537 string.set_attribute(
538 cf_range,
539 kCTFontAttributeName,
540 &font.native_font().clone_with_font_size(font_size.into()),
541 );
542
543 let typesetter = CTTypesetterCreateWithAttributedString(string.as_concrete_TypeRef());
544 let mut ix_converter = StringIndexConverter::new(text);
545 let mut break_indices = Vec::new();
546 while ix_converter.utf8_ix < text.len() {
547 let utf16_len = CTTypesetterSuggestLineBreak(
548 typesetter,
549 ix_converter.utf16_ix as isize,
550 width.into(),
551 ) as usize;
552 ix_converter.advance_to_utf16_ix(ix_converter.utf16_ix + utf16_len);
553 if ix_converter.utf8_ix >= text.len() {
554 break;
555 }
556 break_indices.push(ix_converter.utf8_ix);
557 }
558 break_indices
559 }
560 }
561}
562
563#[derive(Clone)]
564struct StringIndexConverter<'a> {
565 text: &'a str,
566 utf8_ix: usize,
567 utf16_ix: usize,
568}
569
570impl<'a> StringIndexConverter<'a> {
571 fn new(text: &'a str) -> Self {
572 Self {
573 text,
574 utf8_ix: 0,
575 utf16_ix: 0,
576 }
577 }
578
579 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
580 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
581 if self.utf8_ix + ix >= utf8_target {
582 self.utf8_ix += ix;
583 return;
584 }
585 self.utf16_ix += c.len_utf16();
586 }
587 self.utf8_ix = self.text.len();
588 }
589
590 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
591 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
592 if self.utf16_ix >= utf16_target {
593 self.utf8_ix += ix;
594 return;
595 }
596 self.utf16_ix += c.len_utf16();
597 }
598 self.utf8_ix = self.text.len();
599 }
600}
601
602#[repr(C)]
603pub(crate) struct __CFTypesetter(c_void);
604
605type CTTypesetterRef = *const __CFTypesetter;
606
607#[link(name = "CoreText", kind = "framework")]
608extern "C" {
609 fn CTTypesetterCreateWithAttributedString(string: CFAttributedStringRef) -> CTTypesetterRef;
610
611 fn CTTypesetterSuggestLineBreak(
612 typesetter: CTTypesetterRef,
613 start_index: CFIndex,
614 width: f64,
615 ) -> CFIndex;
616}
617
618impl From<Metrics> for FontMetrics {
619 fn from(metrics: Metrics) -> Self {
620 FontMetrics {
621 units_per_em: metrics.units_per_em,
622 ascent: metrics.ascent,
623 descent: metrics.descent,
624 line_gap: metrics.line_gap,
625 underline_position: metrics.underline_position,
626 underline_thickness: metrics.underline_thickness,
627 cap_height: metrics.cap_height,
628 x_height: metrics.x_height,
629 bounding_box: metrics.bounding_box.into(),
630 }
631 }
632}
633
634impl From<RectF> for Bounds<f32> {
635 fn from(rect: RectF) -> Self {
636 Bounds {
637 origin: point(rect.origin_x(), rect.origin_y()),
638 size: size(rect.width(), rect.height()),
639 }
640 }
641}
642
643impl From<RectI> for Bounds<DevicePixels> {
644 fn from(rect: RectI) -> Self {
645 Bounds {
646 origin: point(DevicePixels(rect.origin_x()), DevicePixels(rect.origin_y())),
647 size: size(DevicePixels(rect.width()), DevicePixels(rect.height())),
648 }
649 }
650}
651
652impl From<Vector2I> for Size<DevicePixels> {
653 fn from(value: Vector2I) -> Self {
654 size(value.x().into(), value.y().into())
655 }
656}
657
658impl From<RectI> for Bounds<i32> {
659 fn from(rect: RectI) -> Self {
660 Bounds {
661 origin: point(rect.origin_x(), rect.origin_y()),
662 size: size(rect.width(), rect.height()),
663 }
664 }
665}
666
667impl From<Point<u32>> for Vector2I {
668 fn from(size: Point<u32>) -> Self {
669 Vector2I::new(size.x as i32, size.y as i32)
670 }
671}
672
673impl From<Vector2F> for Size<f32> {
674 fn from(vec: Vector2F) -> Self {
675 size(vec.x(), vec.y())
676 }
677}
678
679impl From<FontWeight> for FontkitWeight {
680 fn from(value: FontWeight) -> Self {
681 FontkitWeight(value.0)
682 }
683}
684
685impl From<FontStyle> for FontkitStyle {
686 fn from(style: FontStyle) -> Self {
687 match style {
688 FontStyle::Normal => FontkitStyle::Normal,
689 FontStyle::Italic => FontkitStyle::Italic,
690 FontStyle::Oblique => FontkitStyle::Oblique,
691 }
692 }
693}
694
695// Some fonts may have no attributest despite `core_text` requiring them (and panicking).
696// This is the same version as `core_text` has without `expect` calls.
697mod lenient_font_attributes {
698 use core_foundation::{
699 base::{CFRetain, CFType, TCFType},
700 string::{CFString, CFStringRef},
701 };
702 use core_text::font_descriptor::{
703 kCTFontFamilyNameAttribute, CTFontDescriptor, CTFontDescriptorCopyAttribute,
704 };
705
706 pub fn family_name(descriptor: &CTFontDescriptor) -> Option<String> {
707 unsafe { get_string_attribute(descriptor, kCTFontFamilyNameAttribute) }
708 }
709
710 fn get_string_attribute(
711 descriptor: &CTFontDescriptor,
712 attribute: CFStringRef,
713 ) -> Option<String> {
714 unsafe {
715 let value = CTFontDescriptorCopyAttribute(descriptor.as_concrete_TypeRef(), attribute);
716 if value.is_null() {
717 return None;
718 }
719
720 let value = CFType::wrap_under_create_rule(value);
721 assert!(value.instance_of::<CFString>());
722 let s = wrap_under_get_rule(value.as_CFTypeRef() as CFStringRef);
723 Some(s.to_string())
724 }
725 }
726
727 unsafe fn wrap_under_get_rule(reference: CFStringRef) -> CFString {
728 assert!(!reference.is_null(), "Attempted to create a NULL object.");
729 let reference = CFRetain(reference as *const ::std::os::raw::c_void) as CFStringRef;
730 TCFType::wrap_under_create_rule(reference)
731 }
732}
733
734#[cfg(test)]
735mod tests {
736 use crate::{font, px, FontRun, GlyphId, MacTextSystem, PlatformTextSystem};
737
738 #[test]
739 fn test_wrap_line() {
740 let fonts = MacTextSystem::new();
741 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
742
743 let line = "one two three four five\n";
744 let wrap_boundaries = fonts.wrap_line(line, font_id, px(16.), px(64.0));
745 assert_eq!(wrap_boundaries, &["one two ".len(), "one two three ".len()]);
746
747 let line = "aaa ααα ✋✋✋ 🎉🎉🎉\n";
748 let wrap_boundaries = fonts.wrap_line(line, font_id, px(16.), px(64.0));
749 assert_eq!(
750 wrap_boundaries,
751 &["aaa ααα ".len(), "aaa ααα ✋✋✋ ".len(),]
752 );
753 }
754
755 #[test]
756 fn test_layout_line_bom_char() {
757 let fonts = MacTextSystem::new();
758 let font_id = fonts.font_id(&font("Helvetica")).unwrap();
759 let line = "\u{feff}";
760 let mut style = FontRun {
761 font_id,
762 len: line.len(),
763 };
764
765 let layout = fonts.layout_line(line, px(16.), &[style]);
766 assert_eq!(layout.len, line.len());
767 assert!(layout.runs.is_empty());
768
769 let line = "a\u{feff}b";
770 style.len = line.len();
771 let layout = fonts.layout_line(line, px(16.), &[style]);
772 assert_eq!(layout.len, line.len());
773 assert_eq!(layout.runs.len(), 1);
774 assert_eq!(layout.runs[0].glyphs.len(), 2);
775 assert_eq!(layout.runs[0].glyphs[0].id, GlyphId(68u32)); // a
776 // There's no glyph for \u{feff}
777 assert_eq!(layout.runs[0].glyphs[1].id, GlyphId(69u32)); // b
778 }
779}