1use std::{borrow::Cow, sync::Arc};
2
3use ::util::ResultExt;
4use anyhow::{anyhow, Result};
5use collections::HashMap;
6use itertools::Itertools;
7use parking_lot::{RwLock, RwLockUpgradableReadGuard};
8use smallvec::SmallVec;
9use windows::{
10 core::*,
11 Win32::{
12 Foundation::*,
13 Globalization::GetUserDefaultLocaleName,
14 Graphics::{
15 Direct2D::{Common::*, *},
16 DirectWrite::*,
17 Dxgi::Common::*,
18 Gdi::LOGFONTW,
19 Imaging::*,
20 },
21 System::SystemServices::LOCALE_NAME_MAX_LENGTH,
22 UI::WindowsAndMessaging::*,
23 },
24};
25use windows_numerics::Vector2;
26
27use crate::*;
28
29#[derive(Debug)]
30struct FontInfo {
31 font_family: String,
32 font_face: IDWriteFontFace3,
33 features: IDWriteTypography,
34 fallbacks: Option<IDWriteFontFallback>,
35 is_system_font: bool,
36 is_emoji: bool,
37}
38
39pub(crate) struct DirectWriteTextSystem(RwLock<DirectWriteState>);
40
41struct DirectWriteComponent {
42 locale: String,
43 factory: IDWriteFactory5,
44 bitmap_factory: AgileReference<IWICImagingFactory>,
45 d2d1_factory: ID2D1Factory,
46 in_memory_loader: IDWriteInMemoryFontFileLoader,
47 builder: IDWriteFontSetBuilder1,
48 text_renderer: Arc<TextRendererWrapper>,
49 render_context: GlyphRenderContext,
50}
51
52struct GlyphRenderContext {
53 params: IDWriteRenderingParams3,
54 dc_target: ID2D1DeviceContext4,
55}
56
57struct DirectWriteState {
58 components: DirectWriteComponent,
59 system_ui_font_name: SharedString,
60 system_font_collection: IDWriteFontCollection1,
61 custom_font_collection: IDWriteFontCollection1,
62 fonts: Vec<FontInfo>,
63 font_selections: HashMap<Font, FontId>,
64 font_id_by_identifier: HashMap<FontIdentifier, FontId>,
65}
66
67#[derive(Debug, Clone, Hash, PartialEq, Eq)]
68struct FontIdentifier {
69 postscript_name: String,
70 weight: i32,
71 style: i32,
72}
73
74impl DirectWriteComponent {
75 pub fn new(bitmap_factory: &IWICImagingFactory) -> Result<Self> {
76 unsafe {
77 let factory: IDWriteFactory5 = DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED)?;
78 let bitmap_factory = AgileReference::new(bitmap_factory)?;
79 let d2d1_factory: ID2D1Factory =
80 D2D1CreateFactory(D2D1_FACTORY_TYPE_MULTI_THREADED, None)?;
81 // The `IDWriteInMemoryFontFileLoader` here is supported starting from
82 // Windows 10 Creators Update, which consequently requires the entire
83 // `DirectWriteTextSystem` to run on `win10 1703`+.
84 let in_memory_loader = factory.CreateInMemoryFontFileLoader()?;
85 factory.RegisterFontFileLoader(&in_memory_loader)?;
86 let builder = factory.CreateFontSetBuilder()?;
87 let mut locale_vec = vec![0u16; LOCALE_NAME_MAX_LENGTH as usize];
88 GetUserDefaultLocaleName(&mut locale_vec);
89 let locale = String::from_utf16_lossy(&locale_vec);
90 let text_renderer = Arc::new(TextRendererWrapper::new(&locale));
91 let render_context = GlyphRenderContext::new(&factory, &d2d1_factory)?;
92
93 Ok(DirectWriteComponent {
94 locale,
95 factory,
96 bitmap_factory,
97 d2d1_factory,
98 in_memory_loader,
99 builder,
100 text_renderer,
101 render_context,
102 })
103 }
104 }
105}
106
107impl GlyphRenderContext {
108 pub fn new(factory: &IDWriteFactory5, d2d1_factory: &ID2D1Factory) -> Result<Self> {
109 unsafe {
110 let default_params: IDWriteRenderingParams3 =
111 factory.CreateRenderingParams()?.cast()?;
112 let gamma = default_params.GetGamma();
113 let enhanced_contrast = default_params.GetEnhancedContrast();
114 let gray_contrast = default_params.GetGrayscaleEnhancedContrast();
115 let cleartype_level = default_params.GetClearTypeLevel();
116 let grid_fit_mode = default_params.GetGridFitMode();
117
118 let params = factory.CreateCustomRenderingParams(
119 gamma,
120 enhanced_contrast,
121 gray_contrast,
122 cleartype_level,
123 DWRITE_PIXEL_GEOMETRY_RGB,
124 DWRITE_RENDERING_MODE1_NATURAL_SYMMETRIC,
125 grid_fit_mode,
126 )?;
127 let dc_target = {
128 let target = d2d1_factory.CreateDCRenderTarget(&get_render_target_property(
129 DXGI_FORMAT_B8G8R8A8_UNORM,
130 D2D1_ALPHA_MODE_PREMULTIPLIED,
131 ))?;
132 let target = target.cast::<ID2D1DeviceContext4>()?;
133 target.SetTextRenderingParams(¶ms);
134 target
135 };
136
137 Ok(Self { params, dc_target })
138 }
139 }
140}
141
142impl DirectWriteTextSystem {
143 pub(crate) fn new(bitmap_factory: &IWICImagingFactory) -> Result<Self> {
144 let components = DirectWriteComponent::new(bitmap_factory)?;
145 let system_font_collection = unsafe {
146 let mut result = std::mem::zeroed();
147 components
148 .factory
149 .GetSystemFontCollection(false, &mut result, true)?;
150 result.unwrap()
151 };
152 let custom_font_set = unsafe { components.builder.CreateFontSet()? };
153 let custom_font_collection = unsafe {
154 components
155 .factory
156 .CreateFontCollectionFromFontSet(&custom_font_set)?
157 };
158 let system_ui_font_name = get_system_ui_font_name();
159
160 Ok(Self(RwLock::new(DirectWriteState {
161 components,
162 system_ui_font_name,
163 system_font_collection,
164 custom_font_collection,
165 fonts: Vec::new(),
166 font_selections: HashMap::default(),
167 font_id_by_identifier: HashMap::default(),
168 })))
169 }
170}
171
172impl PlatformTextSystem for DirectWriteTextSystem {
173 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
174 self.0.write().add_fonts(fonts)
175 }
176
177 fn all_font_names(&self) -> Vec<String> {
178 self.0.read().all_font_names()
179 }
180
181 fn font_id(&self, font: &Font) -> Result<FontId> {
182 let lock = self.0.upgradable_read();
183 if let Some(font_id) = lock.font_selections.get(font) {
184 Ok(*font_id)
185 } else {
186 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
187 let font_id = lock.select_font(font);
188 lock.font_selections.insert(font.clone(), font_id);
189 Ok(font_id)
190 }
191 }
192
193 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
194 self.0.read().font_metrics(font_id)
195 }
196
197 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
198 self.0.read().get_typographic_bounds(font_id, glyph_id)
199 }
200
201 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> anyhow::Result<Size<f32>> {
202 self.0.read().get_advance(font_id, glyph_id)
203 }
204
205 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
206 self.0.read().glyph_for_char(font_id, ch)
207 }
208
209 fn glyph_raster_bounds(
210 &self,
211 params: &RenderGlyphParams,
212 ) -> anyhow::Result<Bounds<DevicePixels>> {
213 self.0.read().raster_bounds(params)
214 }
215
216 fn rasterize_glyph(
217 &self,
218 params: &RenderGlyphParams,
219 raster_bounds: Bounds<DevicePixels>,
220 ) -> anyhow::Result<(Size<DevicePixels>, Vec<u8>)> {
221 self.0.read().rasterize_glyph(params, raster_bounds)
222 }
223
224 fn layout_line(&self, text: &str, font_size: Pixels, runs: &[FontRun]) -> LineLayout {
225 self.0
226 .write()
227 .layout_line(text, font_size, runs)
228 .log_err()
229 .unwrap_or(LineLayout {
230 font_size,
231 ..Default::default()
232 })
233 }
234}
235
236impl DirectWriteState {
237 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
238 for font_data in fonts {
239 match font_data {
240 Cow::Borrowed(data) => unsafe {
241 let font_file = self
242 .components
243 .in_memory_loader
244 .CreateInMemoryFontFileReference(
245 &self.components.factory,
246 data.as_ptr() as _,
247 data.len() as _,
248 None,
249 )?;
250 self.components.builder.AddFontFile(&font_file)?;
251 },
252 Cow::Owned(data) => unsafe {
253 let font_file = self
254 .components
255 .in_memory_loader
256 .CreateInMemoryFontFileReference(
257 &self.components.factory,
258 data.as_ptr() as _,
259 data.len() as _,
260 None,
261 )?;
262 self.components.builder.AddFontFile(&font_file)?;
263 },
264 }
265 }
266 let set = unsafe { self.components.builder.CreateFontSet()? };
267 let collection = unsafe {
268 self.components
269 .factory
270 .CreateFontCollectionFromFontSet(&set)?
271 };
272 self.custom_font_collection = collection;
273
274 Ok(())
275 }
276
277 fn generate_font_fallbacks(
278 &self,
279 fallbacks: &FontFallbacks,
280 ) -> Result<Option<IDWriteFontFallback>> {
281 if fallbacks.fallback_list().is_empty() {
282 return Ok(None);
283 }
284 unsafe {
285 let builder = self.components.factory.CreateFontFallbackBuilder()?;
286 let font_set = &self.system_font_collection.GetFontSet()?;
287 for family_name in fallbacks.fallback_list() {
288 let Some(fonts) = font_set
289 .GetMatchingFonts(
290 &HSTRING::from(family_name),
291 DWRITE_FONT_WEIGHT_NORMAL,
292 DWRITE_FONT_STRETCH_NORMAL,
293 DWRITE_FONT_STYLE_NORMAL,
294 )
295 .log_err()
296 else {
297 continue;
298 };
299 if fonts.GetFontCount() == 0 {
300 log::error!("No matching font found for {}", family_name);
301 continue;
302 }
303 let font = fonts.GetFontFaceReference(0)?.CreateFontFace()?;
304 let mut count = 0;
305 font.GetUnicodeRanges(None, &mut count).ok();
306 if count == 0 {
307 continue;
308 }
309 let mut unicode_ranges = vec![DWRITE_UNICODE_RANGE::default(); count as usize];
310 let Some(_) = font
311 .GetUnicodeRanges(Some(&mut unicode_ranges), &mut count)
312 .log_err()
313 else {
314 continue;
315 };
316 let target_family_name = HSTRING::from(family_name);
317 builder.AddMapping(
318 &unicode_ranges,
319 &[target_family_name.as_ptr()],
320 None,
321 None,
322 None,
323 1.0,
324 )?;
325 }
326 let system_fallbacks = self.components.factory.GetSystemFontFallback()?;
327 builder.AddMappings(&system_fallbacks)?;
328 Ok(Some(builder.CreateFontFallback()?))
329 }
330 }
331
332 unsafe fn generate_font_features(
333 &self,
334 font_features: &FontFeatures,
335 ) -> Result<IDWriteTypography> {
336 let direct_write_features = self.components.factory.CreateTypography()?;
337 apply_font_features(&direct_write_features, font_features)?;
338 Ok(direct_write_features)
339 }
340
341 unsafe fn get_font_id_from_font_collection(
342 &mut self,
343 family_name: &str,
344 font_weight: FontWeight,
345 font_style: FontStyle,
346 font_features: &FontFeatures,
347 font_fallbacks: Option<&FontFallbacks>,
348 is_system_font: bool,
349 ) -> Option<FontId> {
350 let collection = if is_system_font {
351 &self.system_font_collection
352 } else {
353 &self.custom_font_collection
354 };
355 let fontset = collection.GetFontSet().log_err()?;
356 let font = fontset
357 .GetMatchingFonts(
358 &HSTRING::from(family_name),
359 font_weight.into(),
360 DWRITE_FONT_STRETCH_NORMAL,
361 font_style.into(),
362 )
363 .log_err()?;
364 let total_number = font.GetFontCount();
365 for index in 0..total_number {
366 let Some(font_face_ref) = font.GetFontFaceReference(index).log_err() else {
367 continue;
368 };
369 let Some(font_face) = font_face_ref.CreateFontFace().log_err() else {
370 continue;
371 };
372 let Some(identifier) = get_font_identifier(&font_face, &self.components.locale) else {
373 continue;
374 };
375 let is_emoji = font_face.IsColorFont().as_bool();
376 let Some(direct_write_features) = self.generate_font_features(font_features).log_err()
377 else {
378 continue;
379 };
380 let fallbacks = font_fallbacks
381 .and_then(|fallbacks| self.generate_font_fallbacks(fallbacks).log_err().flatten());
382 let font_info = FontInfo {
383 font_family: family_name.to_owned(),
384 font_face,
385 features: direct_write_features,
386 fallbacks,
387 is_system_font,
388 is_emoji,
389 };
390 let font_id = FontId(self.fonts.len());
391 self.fonts.push(font_info);
392 self.font_id_by_identifier.insert(identifier, font_id);
393 return Some(font_id);
394 }
395 None
396 }
397
398 unsafe fn update_system_font_collection(&mut self) {
399 let mut collection = std::mem::zeroed();
400 if self
401 .components
402 .factory
403 .GetSystemFontCollection(false, &mut collection, true)
404 .log_err()
405 .is_some()
406 {
407 self.system_font_collection = collection.unwrap();
408 }
409 }
410
411 fn select_font(&mut self, target_font: &Font) -> FontId {
412 unsafe {
413 if target_font.family == ".SystemUIFont" {
414 let family = self.system_ui_font_name.clone();
415 self.find_font_id(
416 family.as_ref(),
417 target_font.weight,
418 target_font.style,
419 &target_font.features,
420 target_font.fallbacks.as_ref(),
421 )
422 .unwrap()
423 } else {
424 self.find_font_id(
425 target_font.family.as_ref(),
426 target_font.weight,
427 target_font.style,
428 &target_font.features,
429 target_font.fallbacks.as_ref(),
430 )
431 .unwrap_or_else(|| {
432 #[cfg(any(test, feature = "test-support"))]
433 {
434 panic!("ERROR: {} font not found!", target_font.family);
435 }
436 #[cfg(not(any(test, feature = "test-support")))]
437 {
438 let family = self.system_ui_font_name.clone();
439 log::error!("{} not found, use {} instead.", target_font.family, family);
440 self.get_font_id_from_font_collection(
441 family.as_ref(),
442 target_font.weight,
443 target_font.style,
444 &target_font.features,
445 target_font.fallbacks.as_ref(),
446 true,
447 )
448 .unwrap()
449 }
450 })
451 }
452 }
453 }
454
455 unsafe fn find_font_id(
456 &mut self,
457 family_name: &str,
458 weight: FontWeight,
459 style: FontStyle,
460 features: &FontFeatures,
461 fallbacks: Option<&FontFallbacks>,
462 ) -> Option<FontId> {
463 // try to find target font in custom font collection first
464 self.get_font_id_from_font_collection(
465 family_name,
466 weight,
467 style,
468 features,
469 fallbacks,
470 false,
471 )
472 .or_else(|| {
473 self.get_font_id_from_font_collection(
474 family_name,
475 weight,
476 style,
477 features,
478 fallbacks,
479 true,
480 )
481 })
482 .or_else(|| {
483 self.update_system_font_collection();
484 self.get_font_id_from_font_collection(
485 family_name,
486 weight,
487 style,
488 features,
489 fallbacks,
490 true,
491 )
492 })
493 }
494
495 fn layout_line(
496 &mut self,
497 text: &str,
498 font_size: Pixels,
499 font_runs: &[FontRun],
500 ) -> Result<LineLayout> {
501 if font_runs.is_empty() {
502 return Ok(LineLayout {
503 font_size,
504 ..Default::default()
505 });
506 }
507 unsafe {
508 let text_renderer = self.components.text_renderer.clone();
509 let text_wide = text.encode_utf16().collect_vec();
510
511 let mut utf8_offset = 0usize;
512 let mut utf16_offset = 0u32;
513 let text_layout = {
514 let first_run = &font_runs[0];
515 let font_info = &self.fonts[first_run.font_id.0];
516 let collection = if font_info.is_system_font {
517 &self.system_font_collection
518 } else {
519 &self.custom_font_collection
520 };
521 let format: IDWriteTextFormat1 = self
522 .components
523 .factory
524 .CreateTextFormat(
525 &HSTRING::from(&font_info.font_family),
526 collection,
527 font_info.font_face.GetWeight(),
528 font_info.font_face.GetStyle(),
529 DWRITE_FONT_STRETCH_NORMAL,
530 font_size.0,
531 &HSTRING::from(&self.components.locale),
532 )?
533 .cast()?;
534 if let Some(ref fallbacks) = font_info.fallbacks {
535 format.SetFontFallback(fallbacks)?;
536 }
537
538 let layout = self.components.factory.CreateTextLayout(
539 &text_wide,
540 &format,
541 f32::INFINITY,
542 f32::INFINITY,
543 )?;
544 let current_text = &text[utf8_offset..(utf8_offset + first_run.len)];
545 utf8_offset += first_run.len;
546 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
547 let text_range = DWRITE_TEXT_RANGE {
548 startPosition: utf16_offset,
549 length: current_text_utf16_length,
550 };
551 layout.SetTypography(&font_info.features, text_range)?;
552 utf16_offset += current_text_utf16_length;
553
554 layout
555 };
556
557 let mut first_run = true;
558 let mut ascent = Pixels::default();
559 let mut descent = Pixels::default();
560 for run in font_runs {
561 if first_run {
562 first_run = false;
563 let mut metrics = vec![DWRITE_LINE_METRICS::default(); 4];
564 let mut line_count = 0u32;
565 text_layout.GetLineMetrics(Some(&mut metrics), &mut line_count as _)?;
566 ascent = px(metrics[0].baseline);
567 descent = px(metrics[0].height - metrics[0].baseline);
568 continue;
569 }
570 let font_info = &self.fonts[run.font_id.0];
571 let current_text = &text[utf8_offset..(utf8_offset + run.len)];
572 utf8_offset += run.len;
573 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
574
575 let collection = if font_info.is_system_font {
576 &self.system_font_collection
577 } else {
578 &self.custom_font_collection
579 };
580 let text_range = DWRITE_TEXT_RANGE {
581 startPosition: utf16_offset,
582 length: current_text_utf16_length,
583 };
584 utf16_offset += current_text_utf16_length;
585 text_layout.SetFontCollection(collection, text_range)?;
586 text_layout
587 .SetFontFamilyName(&HSTRING::from(&font_info.font_family), text_range)?;
588 text_layout.SetFontSize(font_size.0, text_range)?;
589 text_layout.SetFontStyle(font_info.font_face.GetStyle(), text_range)?;
590 text_layout.SetFontWeight(font_info.font_face.GetWeight(), text_range)?;
591 text_layout.SetTypography(&font_info.features, text_range)?;
592 }
593
594 let mut runs = Vec::new();
595 let renderer_context = RendererContext {
596 text_system: self,
597 index_converter: StringIndexConverter::new(text),
598 runs: &mut runs,
599 utf16_index: 0,
600 width: 0.0,
601 };
602 text_layout.Draw(
603 Some(&renderer_context as *const _ as _),
604 &text_renderer.0,
605 0.0,
606 0.0,
607 )?;
608 let width = px(renderer_context.width);
609
610 Ok(LineLayout {
611 font_size,
612 width,
613 ascent,
614 descent,
615 runs,
616 len: text.len(),
617 })
618 }
619 }
620
621 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
622 unsafe {
623 let font_info = &self.fonts[font_id.0];
624 let mut metrics = std::mem::zeroed();
625 font_info.font_face.GetMetrics(&mut metrics);
626
627 FontMetrics {
628 units_per_em: metrics.Base.designUnitsPerEm as _,
629 ascent: metrics.Base.ascent as _,
630 descent: -(metrics.Base.descent as f32),
631 line_gap: metrics.Base.lineGap as _,
632 underline_position: metrics.Base.underlinePosition as _,
633 underline_thickness: metrics.Base.underlineThickness as _,
634 cap_height: metrics.Base.capHeight as _,
635 x_height: metrics.Base.xHeight as _,
636 bounding_box: Bounds {
637 origin: Point {
638 x: metrics.glyphBoxLeft as _,
639 y: metrics.glyphBoxBottom as _,
640 },
641 size: Size {
642 width: (metrics.glyphBoxRight - metrics.glyphBoxLeft) as _,
643 height: (metrics.glyphBoxTop - metrics.glyphBoxBottom) as _,
644 },
645 },
646 }
647 }
648 }
649
650 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
651 let render_target = &self.components.render_context.dc_target;
652 unsafe {
653 render_target.SetUnitMode(D2D1_UNIT_MODE_DIPS);
654 render_target.SetDpi(96.0 * params.scale_factor, 96.0 * params.scale_factor);
655 }
656 let font = &self.fonts[params.font_id.0];
657 let glyph_id = [params.glyph_id.0 as u16];
658 let advance = [0.0f32];
659 let offset = [DWRITE_GLYPH_OFFSET::default()];
660 let glyph_run = DWRITE_GLYPH_RUN {
661 fontFace: unsafe { std::mem::transmute_copy(&font.font_face) },
662 fontEmSize: params.font_size.0,
663 glyphCount: 1,
664 glyphIndices: glyph_id.as_ptr(),
665 glyphAdvances: advance.as_ptr(),
666 glyphOffsets: offset.as_ptr(),
667 isSideways: BOOL(0),
668 bidiLevel: 0,
669 };
670 let bounds = unsafe {
671 render_target.GetGlyphRunWorldBounds(
672 Vector2 { X: 0.0, Y: 0.0 },
673 &glyph_run,
674 DWRITE_MEASURING_MODE_NATURAL,
675 )?
676 };
677 // todo(windows)
678 // This is a walkaround, deleted when figured out.
679 let y_offset;
680 let extra_height;
681 if params.is_emoji {
682 y_offset = 0;
683 extra_height = 0;
684 } else {
685 // make some room for scaler.
686 y_offset = -1;
687 extra_height = 2;
688 }
689
690 if bounds.right < bounds.left {
691 Ok(Bounds {
692 origin: point(0.into(), 0.into()),
693 size: size(0.into(), 0.into()),
694 })
695 } else {
696 Ok(Bounds {
697 origin: point(
698 ((bounds.left * params.scale_factor).ceil() as i32).into(),
699 ((bounds.top * params.scale_factor).ceil() as i32 + y_offset).into(),
700 ),
701 size: size(
702 (((bounds.right - bounds.left) * params.scale_factor).ceil() as i32).into(),
703 (((bounds.bottom - bounds.top) * params.scale_factor).ceil() as i32
704 + extra_height)
705 .into(),
706 ),
707 })
708 }
709 }
710
711 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
712 let font_info = &self.fonts[font_id.0];
713 let codepoints = [ch as u32];
714 let mut glyph_indices = vec![0u16; 1];
715 unsafe {
716 font_info
717 .font_face
718 .GetGlyphIndices(codepoints.as_ptr(), 1, glyph_indices.as_mut_ptr())
719 .log_err()
720 }
721 .map(|_| GlyphId(glyph_indices[0] as u32))
722 }
723
724 fn rasterize_glyph(
725 &self,
726 params: &RenderGlyphParams,
727 glyph_bounds: Bounds<DevicePixels>,
728 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
729 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
730 return Err(anyhow!("glyph bounds are empty"));
731 }
732
733 let font_info = &self.fonts[params.font_id.0];
734 let glyph_id = [params.glyph_id.0 as u16];
735 let advance = [glyph_bounds.size.width.0 as f32];
736 let offset = [DWRITE_GLYPH_OFFSET {
737 advanceOffset: -glyph_bounds.origin.x.0 as f32 / params.scale_factor,
738 ascenderOffset: glyph_bounds.origin.y.0 as f32 / params.scale_factor,
739 }];
740 let glyph_run = DWRITE_GLYPH_RUN {
741 fontFace: unsafe { std::mem::transmute_copy(&font_info.font_face) },
742 fontEmSize: params.font_size.0,
743 glyphCount: 1,
744 glyphIndices: glyph_id.as_ptr(),
745 glyphAdvances: advance.as_ptr(),
746 glyphOffsets: offset.as_ptr(),
747 isSideways: BOOL(0),
748 bidiLevel: 0,
749 };
750
751 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
752 let mut bitmap_size = glyph_bounds.size;
753 if params.subpixel_variant.x > 0 {
754 bitmap_size.width += DevicePixels(1);
755 }
756 if params.subpixel_variant.y > 0 {
757 bitmap_size.height += DevicePixels(1);
758 }
759 let bitmap_size = bitmap_size;
760
761 let total_bytes;
762 let bitmap_format;
763 let render_target_property;
764 let bitmap_width;
765 let bitmap_height;
766 let bitmap_stride;
767 let bitmap_dpi;
768 if params.is_emoji {
769 total_bytes = bitmap_size.height.0 as usize * bitmap_size.width.0 as usize * 4;
770 bitmap_format = &GUID_WICPixelFormat32bppPBGRA;
771 render_target_property = get_render_target_property(
772 DXGI_FORMAT_B8G8R8A8_UNORM,
773 D2D1_ALPHA_MODE_PREMULTIPLIED,
774 );
775 bitmap_width = bitmap_size.width.0 as u32;
776 bitmap_height = bitmap_size.height.0 as u32;
777 bitmap_stride = bitmap_size.width.0 as u32 * 4;
778 bitmap_dpi = 96.0;
779 } else {
780 total_bytes = bitmap_size.height.0 as usize * bitmap_size.width.0 as usize;
781 bitmap_format = &GUID_WICPixelFormat8bppAlpha;
782 render_target_property =
783 get_render_target_property(DXGI_FORMAT_A8_UNORM, D2D1_ALPHA_MODE_STRAIGHT);
784 bitmap_width = bitmap_size.width.0 as u32 * 2;
785 bitmap_height = bitmap_size.height.0 as u32 * 2;
786 bitmap_stride = bitmap_size.width.0 as u32;
787 bitmap_dpi = 192.0;
788 }
789
790 let bitmap_factory = self.components.bitmap_factory.resolve()?;
791 unsafe {
792 let bitmap = bitmap_factory.CreateBitmap(
793 bitmap_width,
794 bitmap_height,
795 bitmap_format,
796 WICBitmapCacheOnLoad,
797 )?;
798 let render_target = self
799 .components
800 .d2d1_factory
801 .CreateWicBitmapRenderTarget(&bitmap, &render_target_property)?;
802 let brush = render_target.CreateSolidColorBrush(&BRUSH_COLOR, None)?;
803 let subpixel_shift = params
804 .subpixel_variant
805 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
806 let baseline_origin = Vector2 {
807 X: subpixel_shift.x / params.scale_factor,
808 Y: subpixel_shift.y / params.scale_factor,
809 };
810
811 // This `cast()` action here should never fail since we are running on Win10+, and
812 // ID2D1DeviceContext4 requires Win8+
813 let render_target = render_target.cast::<ID2D1DeviceContext4>().unwrap();
814 render_target.SetUnitMode(D2D1_UNIT_MODE_DIPS);
815 render_target.SetDpi(
816 bitmap_dpi * params.scale_factor,
817 bitmap_dpi * params.scale_factor,
818 );
819 render_target.SetTextRenderingParams(&self.components.render_context.params);
820 render_target.BeginDraw();
821
822 if params.is_emoji {
823 // WARN: only DWRITE_GLYPH_IMAGE_FORMATS_COLR has been tested
824 let enumerator = self.components.factory.TranslateColorGlyphRun(
825 baseline_origin,
826 &glyph_run as _,
827 None,
828 DWRITE_GLYPH_IMAGE_FORMATS_COLR
829 | DWRITE_GLYPH_IMAGE_FORMATS_SVG
830 | DWRITE_GLYPH_IMAGE_FORMATS_PNG
831 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
832 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8,
833 DWRITE_MEASURING_MODE_NATURAL,
834 None,
835 0,
836 )?;
837 while enumerator.MoveNext().is_ok() {
838 let Ok(color_glyph) = enumerator.GetCurrentRun() else {
839 break;
840 };
841 let color_glyph = &*color_glyph;
842 let brush_color = translate_color(&color_glyph.Base.runColor);
843 brush.SetColor(&brush_color);
844 match color_glyph.glyphImageFormat {
845 DWRITE_GLYPH_IMAGE_FORMATS_PNG
846 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
847 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8 => render_target
848 .DrawColorBitmapGlyphRun(
849 color_glyph.glyphImageFormat,
850 baseline_origin,
851 &color_glyph.Base.glyphRun,
852 color_glyph.measuringMode,
853 D2D1_COLOR_BITMAP_GLYPH_SNAP_OPTION_DEFAULT,
854 ),
855 DWRITE_GLYPH_IMAGE_FORMATS_SVG => render_target.DrawSvgGlyphRun(
856 baseline_origin,
857 &color_glyph.Base.glyphRun,
858 &brush,
859 None,
860 color_glyph.Base.paletteIndex as u32,
861 color_glyph.measuringMode,
862 ),
863 _ => render_target.DrawGlyphRun(
864 baseline_origin,
865 &color_glyph.Base.glyphRun,
866 Some(color_glyph.Base.glyphRunDescription as *const _),
867 &brush,
868 color_glyph.measuringMode,
869 ),
870 }
871 }
872 } else {
873 render_target.DrawGlyphRun(
874 baseline_origin,
875 &glyph_run,
876 None,
877 &brush,
878 DWRITE_MEASURING_MODE_NATURAL,
879 );
880 }
881 render_target.EndDraw(None, None)?;
882
883 let mut raw_data = vec![0u8; total_bytes];
884 if params.is_emoji {
885 bitmap.CopyPixels(std::ptr::null() as _, bitmap_stride, &mut raw_data)?;
886 // Convert from BGRA with premultiplied alpha to BGRA with straight alpha.
887 for pixel in raw_data.chunks_exact_mut(4) {
888 let a = pixel[3] as f32 / 255.;
889 pixel[0] = (pixel[0] as f32 / a) as u8;
890 pixel[1] = (pixel[1] as f32 / a) as u8;
891 pixel[2] = (pixel[2] as f32 / a) as u8;
892 }
893 } else {
894 let scaler = bitmap_factory.CreateBitmapScaler()?;
895 scaler.Initialize(
896 &bitmap,
897 bitmap_size.width.0 as u32,
898 bitmap_size.height.0 as u32,
899 WICBitmapInterpolationModeHighQualityCubic,
900 )?;
901 scaler.CopyPixels(std::ptr::null() as _, bitmap_stride, &mut raw_data)?;
902 }
903 Ok((bitmap_size, raw_data))
904 }
905 }
906
907 fn get_typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
908 unsafe {
909 let font = &self.fonts[font_id.0].font_face;
910 let glyph_indices = [glyph_id.0 as u16];
911 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
912 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
913
914 let metrics = &metrics[0];
915 let advance_width = metrics.advanceWidth as i32;
916 let advance_height = metrics.advanceHeight as i32;
917 let left_side_bearing = metrics.leftSideBearing;
918 let right_side_bearing = metrics.rightSideBearing;
919 let top_side_bearing = metrics.topSideBearing;
920 let bottom_side_bearing = metrics.bottomSideBearing;
921 let vertical_origin_y = metrics.verticalOriginY;
922
923 let y_offset = vertical_origin_y + bottom_side_bearing - advance_height;
924 let width = advance_width - (left_side_bearing + right_side_bearing);
925 let height = advance_height - (top_side_bearing + bottom_side_bearing);
926
927 Ok(Bounds {
928 origin: Point {
929 x: left_side_bearing as f32,
930 y: y_offset as f32,
931 },
932 size: Size {
933 width: width as f32,
934 height: height as f32,
935 },
936 })
937 }
938 }
939
940 fn get_advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
941 unsafe {
942 let font = &self.fonts[font_id.0].font_face;
943 let glyph_indices = [glyph_id.0 as u16];
944 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
945 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
946
947 let metrics = &metrics[0];
948
949 Ok(Size {
950 width: metrics.advanceWidth as f32,
951 height: 0.0,
952 })
953 }
954 }
955
956 fn all_font_names(&self) -> Vec<String> {
957 let mut result =
958 get_font_names_from_collection(&self.system_font_collection, &self.components.locale);
959 result.extend(get_font_names_from_collection(
960 &self.custom_font_collection,
961 &self.components.locale,
962 ));
963 result
964 }
965}
966
967impl Drop for DirectWriteState {
968 fn drop(&mut self) {
969 unsafe {
970 let _ = self
971 .components
972 .factory
973 .UnregisterFontFileLoader(&self.components.in_memory_loader);
974 }
975 }
976}
977
978struct TextRendererWrapper(pub IDWriteTextRenderer);
979
980impl TextRendererWrapper {
981 pub fn new(locale_str: &str) -> Self {
982 let inner = TextRenderer::new(locale_str);
983 TextRendererWrapper(inner.into())
984 }
985}
986
987#[implement(IDWriteTextRenderer)]
988struct TextRenderer {
989 locale: String,
990}
991
992impl TextRenderer {
993 pub fn new(locale_str: &str) -> Self {
994 TextRenderer {
995 locale: locale_str.to_owned(),
996 }
997 }
998}
999
1000struct RendererContext<'t, 'a, 'b> {
1001 text_system: &'t mut DirectWriteState,
1002 index_converter: StringIndexConverter<'a>,
1003 runs: &'b mut Vec<ShapedRun>,
1004 utf16_index: usize,
1005 width: f32,
1006}
1007
1008#[allow(non_snake_case)]
1009impl IDWritePixelSnapping_Impl for TextRenderer_Impl {
1010 fn IsPixelSnappingDisabled(
1011 &self,
1012 _clientdrawingcontext: *const ::core::ffi::c_void,
1013 ) -> windows::core::Result<BOOL> {
1014 Ok(BOOL(0))
1015 }
1016
1017 fn GetCurrentTransform(
1018 &self,
1019 _clientdrawingcontext: *const ::core::ffi::c_void,
1020 transform: *mut DWRITE_MATRIX,
1021 ) -> windows::core::Result<()> {
1022 unsafe {
1023 *transform = DWRITE_MATRIX {
1024 m11: 1.0,
1025 m12: 0.0,
1026 m21: 0.0,
1027 m22: 1.0,
1028 dx: 0.0,
1029 dy: 0.0,
1030 };
1031 }
1032 Ok(())
1033 }
1034
1035 fn GetPixelsPerDip(
1036 &self,
1037 _clientdrawingcontext: *const ::core::ffi::c_void,
1038 ) -> windows::core::Result<f32> {
1039 Ok(1.0)
1040 }
1041}
1042
1043#[allow(non_snake_case)]
1044impl IDWriteTextRenderer_Impl for TextRenderer_Impl {
1045 fn DrawGlyphRun(
1046 &self,
1047 clientdrawingcontext: *const ::core::ffi::c_void,
1048 _baselineoriginx: f32,
1049 _baselineoriginy: f32,
1050 _measuringmode: DWRITE_MEASURING_MODE,
1051 glyphrun: *const DWRITE_GLYPH_RUN,
1052 glyphrundescription: *const DWRITE_GLYPH_RUN_DESCRIPTION,
1053 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1054 ) -> windows::core::Result<()> {
1055 unsafe {
1056 let glyphrun = &*glyphrun;
1057 let glyph_count = glyphrun.glyphCount as usize;
1058 if glyph_count == 0 {
1059 return Ok(());
1060 }
1061 let desc = &*glyphrundescription;
1062 let utf16_length_per_glyph = desc.stringLength as usize / glyph_count;
1063 let context =
1064 &mut *(clientdrawingcontext as *const RendererContext as *mut RendererContext);
1065
1066 if glyphrun.fontFace.is_none() {
1067 return Ok(());
1068 }
1069
1070 let font_face = glyphrun.fontFace.as_ref().unwrap();
1071 // This `cast()` action here should never fail since we are running on Win10+, and
1072 // `IDWriteFontFace3` requires Win10
1073 let font_face = &font_face.cast::<IDWriteFontFace3>().unwrap();
1074 let Some((font_identifier, font_struct, color_font)) =
1075 get_font_identifier_and_font_struct(font_face, &self.locale)
1076 else {
1077 return Ok(());
1078 };
1079
1080 let font_id = if let Some(id) = context
1081 .text_system
1082 .font_id_by_identifier
1083 .get(&font_identifier)
1084 {
1085 *id
1086 } else {
1087 context.text_system.select_font(&font_struct)
1088 };
1089 let mut glyphs = SmallVec::new();
1090 for index in 0..glyph_count {
1091 let id = GlyphId(*glyphrun.glyphIndices.add(index) as u32);
1092 context
1093 .index_converter
1094 .advance_to_utf16_ix(context.utf16_index);
1095 let is_emoji = color_font
1096 && is_color_glyph(font_face, id, &context.text_system.components.factory);
1097 glyphs.push(ShapedGlyph {
1098 id,
1099 position: point(px(context.width), px(0.0)),
1100 index: context.index_converter.utf8_ix,
1101 is_emoji,
1102 });
1103 context.utf16_index += utf16_length_per_glyph;
1104 context.width += *glyphrun.glyphAdvances.add(index);
1105 }
1106 context.runs.push(ShapedRun { font_id, glyphs });
1107 }
1108 Ok(())
1109 }
1110
1111 fn DrawUnderline(
1112 &self,
1113 _clientdrawingcontext: *const ::core::ffi::c_void,
1114 _baselineoriginx: f32,
1115 _baselineoriginy: f32,
1116 _underline: *const DWRITE_UNDERLINE,
1117 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1118 ) -> windows::core::Result<()> {
1119 Err(windows::core::Error::new(
1120 E_NOTIMPL,
1121 "DrawUnderline unimplemented",
1122 ))
1123 }
1124
1125 fn DrawStrikethrough(
1126 &self,
1127 _clientdrawingcontext: *const ::core::ffi::c_void,
1128 _baselineoriginx: f32,
1129 _baselineoriginy: f32,
1130 _strikethrough: *const DWRITE_STRIKETHROUGH,
1131 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1132 ) -> windows::core::Result<()> {
1133 Err(windows::core::Error::new(
1134 E_NOTIMPL,
1135 "DrawStrikethrough unimplemented",
1136 ))
1137 }
1138
1139 fn DrawInlineObject(
1140 &self,
1141 _clientdrawingcontext: *const ::core::ffi::c_void,
1142 _originx: f32,
1143 _originy: f32,
1144 _inlineobject: windows::core::Ref<IDWriteInlineObject>,
1145 _issideways: BOOL,
1146 _isrighttoleft: BOOL,
1147 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1148 ) -> windows::core::Result<()> {
1149 Err(windows::core::Error::new(
1150 E_NOTIMPL,
1151 "DrawInlineObject unimplemented",
1152 ))
1153 }
1154}
1155
1156struct StringIndexConverter<'a> {
1157 text: &'a str,
1158 utf8_ix: usize,
1159 utf16_ix: usize,
1160}
1161
1162impl<'a> StringIndexConverter<'a> {
1163 fn new(text: &'a str) -> Self {
1164 Self {
1165 text,
1166 utf8_ix: 0,
1167 utf16_ix: 0,
1168 }
1169 }
1170
1171 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
1172 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1173 if self.utf8_ix + ix >= utf8_target {
1174 self.utf8_ix += ix;
1175 return;
1176 }
1177 self.utf16_ix += c.len_utf16();
1178 }
1179 self.utf8_ix = self.text.len();
1180 }
1181
1182 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
1183 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1184 if self.utf16_ix >= utf16_target {
1185 self.utf8_ix += ix;
1186 return;
1187 }
1188 self.utf16_ix += c.len_utf16();
1189 }
1190 self.utf8_ix = self.text.len();
1191 }
1192}
1193
1194impl Into<DWRITE_FONT_STYLE> for FontStyle {
1195 fn into(self) -> DWRITE_FONT_STYLE {
1196 match self {
1197 FontStyle::Normal => DWRITE_FONT_STYLE_NORMAL,
1198 FontStyle::Italic => DWRITE_FONT_STYLE_ITALIC,
1199 FontStyle::Oblique => DWRITE_FONT_STYLE_OBLIQUE,
1200 }
1201 }
1202}
1203
1204impl From<DWRITE_FONT_STYLE> for FontStyle {
1205 fn from(value: DWRITE_FONT_STYLE) -> Self {
1206 match value.0 {
1207 0 => FontStyle::Normal,
1208 1 => FontStyle::Italic,
1209 2 => FontStyle::Oblique,
1210 _ => unreachable!(),
1211 }
1212 }
1213}
1214
1215impl Into<DWRITE_FONT_WEIGHT> for FontWeight {
1216 fn into(self) -> DWRITE_FONT_WEIGHT {
1217 DWRITE_FONT_WEIGHT(self.0 as i32)
1218 }
1219}
1220
1221impl From<DWRITE_FONT_WEIGHT> for FontWeight {
1222 fn from(value: DWRITE_FONT_WEIGHT) -> Self {
1223 FontWeight(value.0 as f32)
1224 }
1225}
1226
1227fn get_font_names_from_collection(
1228 collection: &IDWriteFontCollection1,
1229 locale: &str,
1230) -> Vec<String> {
1231 unsafe {
1232 let mut result = Vec::new();
1233 let family_count = collection.GetFontFamilyCount();
1234 for index in 0..family_count {
1235 let Some(font_family) = collection.GetFontFamily(index).log_err() else {
1236 continue;
1237 };
1238 let Some(localized_family_name) = font_family.GetFamilyNames().log_err() else {
1239 continue;
1240 };
1241 let Some(family_name) = get_name(localized_family_name, locale).log_err() else {
1242 continue;
1243 };
1244 result.push(family_name);
1245 }
1246
1247 result
1248 }
1249}
1250
1251fn get_font_identifier_and_font_struct(
1252 font_face: &IDWriteFontFace3,
1253 locale: &str,
1254) -> Option<(FontIdentifier, Font, bool)> {
1255 let postscript_name = get_postscript_name(font_face, locale).log_err()?;
1256 let localized_family_name = unsafe { font_face.GetFamilyNames().log_err() }?;
1257 let family_name = get_name(localized_family_name, locale).log_err()?;
1258 let weight = unsafe { font_face.GetWeight() };
1259 let style = unsafe { font_face.GetStyle() };
1260 let identifier = FontIdentifier {
1261 postscript_name,
1262 weight: weight.0,
1263 style: style.0,
1264 };
1265 let font_struct = Font {
1266 family: family_name.into(),
1267 features: FontFeatures::default(),
1268 weight: weight.into(),
1269 style: style.into(),
1270 fallbacks: None,
1271 };
1272 let is_emoji = unsafe { font_face.IsColorFont().as_bool() };
1273 Some((identifier, font_struct, is_emoji))
1274}
1275
1276#[inline]
1277fn get_font_identifier(font_face: &IDWriteFontFace3, locale: &str) -> Option<FontIdentifier> {
1278 let weight = unsafe { font_face.GetWeight().0 };
1279 let style = unsafe { font_face.GetStyle().0 };
1280 get_postscript_name(font_face, locale)
1281 .log_err()
1282 .map(|postscript_name| FontIdentifier {
1283 postscript_name,
1284 weight,
1285 style,
1286 })
1287}
1288
1289#[inline]
1290fn get_postscript_name(font_face: &IDWriteFontFace3, locale: &str) -> Result<String> {
1291 let mut info = None;
1292 let mut exists = BOOL(0);
1293 unsafe {
1294 font_face.GetInformationalStrings(
1295 DWRITE_INFORMATIONAL_STRING_POSTSCRIPT_NAME,
1296 &mut info,
1297 &mut exists,
1298 )?
1299 };
1300 if !exists.as_bool() || info.is_none() {
1301 return Err(anyhow!("No postscript name found for font face"));
1302 }
1303
1304 get_name(info.unwrap(), locale)
1305}
1306
1307// https://learn.microsoft.com/en-us/windows/win32/api/dwrite/ne-dwrite-dwrite_font_feature_tag
1308fn apply_font_features(
1309 direct_write_features: &IDWriteTypography,
1310 features: &FontFeatures,
1311) -> Result<()> {
1312 let tag_values = features.tag_value_list();
1313 if tag_values.is_empty() {
1314 return Ok(());
1315 }
1316
1317 // All of these features are enabled by default by DirectWrite.
1318 // If you want to (and can) peek into the source of DirectWrite
1319 let mut feature_liga = make_direct_write_feature("liga", 1);
1320 let mut feature_clig = make_direct_write_feature("clig", 1);
1321 let mut feature_calt = make_direct_write_feature("calt", 1);
1322
1323 for (tag, value) in tag_values {
1324 if tag.as_str() == "liga" && *value == 0 {
1325 feature_liga.parameter = 0;
1326 continue;
1327 }
1328 if tag.as_str() == "clig" && *value == 0 {
1329 feature_clig.parameter = 0;
1330 continue;
1331 }
1332 if tag.as_str() == "calt" && *value == 0 {
1333 feature_calt.parameter = 0;
1334 continue;
1335 }
1336
1337 unsafe {
1338 direct_write_features.AddFontFeature(make_direct_write_feature(&tag, *value))?;
1339 }
1340 }
1341 unsafe {
1342 direct_write_features.AddFontFeature(feature_liga)?;
1343 direct_write_features.AddFontFeature(feature_clig)?;
1344 direct_write_features.AddFontFeature(feature_calt)?;
1345 }
1346
1347 Ok(())
1348}
1349
1350#[inline]
1351fn make_direct_write_feature(feature_name: &str, parameter: u32) -> DWRITE_FONT_FEATURE {
1352 let tag = make_direct_write_tag(feature_name);
1353 DWRITE_FONT_FEATURE {
1354 nameTag: tag,
1355 parameter,
1356 }
1357}
1358
1359#[inline]
1360fn make_open_type_tag(tag_name: &str) -> u32 {
1361 let bytes = tag_name.bytes().collect_vec();
1362 assert_eq!(bytes.len(), 4);
1363 ((bytes[3] as u32) << 24)
1364 | ((bytes[2] as u32) << 16)
1365 | ((bytes[1] as u32) << 8)
1366 | (bytes[0] as u32)
1367}
1368
1369#[inline]
1370fn make_direct_write_tag(tag_name: &str) -> DWRITE_FONT_FEATURE_TAG {
1371 DWRITE_FONT_FEATURE_TAG(make_open_type_tag(tag_name))
1372}
1373
1374#[inline]
1375fn get_name(string: IDWriteLocalizedStrings, locale: &str) -> Result<String> {
1376 let mut locale_name_index = 0u32;
1377 let mut exists = BOOL(0);
1378 unsafe {
1379 string.FindLocaleName(
1380 &HSTRING::from(locale),
1381 &mut locale_name_index,
1382 &mut exists as _,
1383 )?
1384 };
1385 if !exists.as_bool() {
1386 unsafe {
1387 string.FindLocaleName(
1388 DEFAULT_LOCALE_NAME,
1389 &mut locale_name_index as _,
1390 &mut exists as _,
1391 )?
1392 };
1393 if !exists.as_bool() {
1394 return Err(anyhow!("No localised string for {}", locale));
1395 }
1396 }
1397
1398 let name_length = unsafe { string.GetStringLength(locale_name_index) }? as usize;
1399 let mut name_vec = vec![0u16; name_length + 1];
1400 unsafe {
1401 string.GetString(locale_name_index, &mut name_vec)?;
1402 }
1403
1404 Ok(String::from_utf16_lossy(&name_vec[..name_length]))
1405}
1406
1407#[inline]
1408fn translate_color(color: &DWRITE_COLOR_F) -> D2D1_COLOR_F {
1409 D2D1_COLOR_F {
1410 r: color.r,
1411 g: color.g,
1412 b: color.b,
1413 a: color.a,
1414 }
1415}
1416
1417fn get_system_ui_font_name() -> SharedString {
1418 unsafe {
1419 let mut info: LOGFONTW = std::mem::zeroed();
1420 let font_family = if SystemParametersInfoW(
1421 SPI_GETICONTITLELOGFONT,
1422 std::mem::size_of::<LOGFONTW>() as u32,
1423 Some(&mut info as *mut _ as _),
1424 SYSTEM_PARAMETERS_INFO_UPDATE_FLAGS(0),
1425 )
1426 .log_err()
1427 .is_none()
1428 {
1429 // https://learn.microsoft.com/en-us/windows/win32/uxguide/vis-fonts
1430 // Segoe UI is the Windows font intended for user interface text strings.
1431 "Segoe UI".into()
1432 } else {
1433 let font_name = String::from_utf16_lossy(&info.lfFaceName);
1434 font_name.trim_matches(char::from(0)).to_owned().into()
1435 };
1436 log::info!("Use {} as UI font.", font_family);
1437 font_family
1438 }
1439}
1440
1441#[inline]
1442fn get_render_target_property(
1443 pixel_format: DXGI_FORMAT,
1444 alpha_mode: D2D1_ALPHA_MODE,
1445) -> D2D1_RENDER_TARGET_PROPERTIES {
1446 D2D1_RENDER_TARGET_PROPERTIES {
1447 r#type: D2D1_RENDER_TARGET_TYPE_DEFAULT,
1448 pixelFormat: D2D1_PIXEL_FORMAT {
1449 format: pixel_format,
1450 alphaMode: alpha_mode,
1451 },
1452 dpiX: 96.0,
1453 dpiY: 96.0,
1454 usage: D2D1_RENDER_TARGET_USAGE_NONE,
1455 minLevel: D2D1_FEATURE_LEVEL_DEFAULT,
1456 }
1457}
1458
1459// One would think that with newer DirectWrite method: IDWriteFontFace4::GetGlyphImageFormats
1460// but that doesn't seem to work for some glyphs, say ❤
1461fn is_color_glyph(
1462 font_face: &IDWriteFontFace3,
1463 glyph_id: GlyphId,
1464 factory: &IDWriteFactory5,
1465) -> bool {
1466 let glyph_run = DWRITE_GLYPH_RUN {
1467 fontFace: unsafe { std::mem::transmute_copy(font_face) },
1468 fontEmSize: 14.0,
1469 glyphCount: 1,
1470 glyphIndices: &(glyph_id.0 as u16),
1471 glyphAdvances: &0.0,
1472 glyphOffsets: &DWRITE_GLYPH_OFFSET {
1473 advanceOffset: 0.0,
1474 ascenderOffset: 0.0,
1475 },
1476 isSideways: BOOL(0),
1477 bidiLevel: 0,
1478 };
1479 unsafe {
1480 factory.TranslateColorGlyphRun(
1481 Vector2::default(),
1482 &glyph_run as _,
1483 None,
1484 DWRITE_GLYPH_IMAGE_FORMATS_COLR
1485 | DWRITE_GLYPH_IMAGE_FORMATS_SVG
1486 | DWRITE_GLYPH_IMAGE_FORMATS_PNG
1487 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
1488 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8,
1489 DWRITE_MEASURING_MODE_NATURAL,
1490 None,
1491 0,
1492 )
1493 }
1494 .is_ok()
1495}
1496
1497const DEFAULT_LOCALE_NAME: PCWSTR = windows::core::w!("en-US");
1498const BRUSH_COLOR: D2D1_COLOR_F = D2D1_COLOR_F {
1499 r: 1.0,
1500 g: 1.0,
1501 b: 1.0,
1502 a: 1.0,
1503};