1use std::{borrow::Cow, sync::Arc};
2
3use ::util::ResultExt;
4use anyhow::Result;
5use collections::HashMap;
6use itertools::Itertools;
7use parking_lot::{RwLock, RwLockUpgradableReadGuard};
8use windows::{
9 Win32::{
10 Foundation::*,
11 Globalization::GetUserDefaultLocaleName,
12 Graphics::{
13 Direct2D::{Common::*, *},
14 DirectWrite::*,
15 Dxgi::Common::*,
16 Gdi::LOGFONTW,
17 Imaging::*,
18 },
19 System::SystemServices::LOCALE_NAME_MAX_LENGTH,
20 UI::WindowsAndMessaging::*,
21 },
22 core::*,
23};
24use windows_numerics::Vector2;
25
26use crate::*;
27
28#[derive(Debug)]
29struct FontInfo {
30 font_family: String,
31 font_face: IDWriteFontFace3,
32 features: IDWriteTypography,
33 fallbacks: Option<IDWriteFontFallback>,
34 is_system_font: bool,
35}
36
37pub(crate) struct DirectWriteTextSystem(RwLock<DirectWriteState>);
38
39struct DirectWriteComponent {
40 locale: String,
41 factory: IDWriteFactory5,
42 bitmap_factory: AgileReference<IWICImagingFactory>,
43 d2d1_factory: ID2D1Factory,
44 in_memory_loader: IDWriteInMemoryFontFileLoader,
45 builder: IDWriteFontSetBuilder1,
46 text_renderer: Arc<TextRendererWrapper>,
47 render_context: GlyphRenderContext,
48}
49
50struct GlyphRenderContext {
51 params: IDWriteRenderingParams3,
52 dc_target: ID2D1DeviceContext4,
53}
54
55struct DirectWriteState {
56 components: DirectWriteComponent,
57 system_ui_font_name: SharedString,
58 system_font_collection: IDWriteFontCollection1,
59 custom_font_collection: IDWriteFontCollection1,
60 fonts: Vec<FontInfo>,
61 font_selections: HashMap<Font, FontId>,
62 font_id_by_identifier: HashMap<FontIdentifier, FontId>,
63}
64
65#[derive(Debug, Clone, Hash, PartialEq, Eq)]
66struct FontIdentifier {
67 postscript_name: String,
68 weight: i32,
69 style: i32,
70}
71
72impl DirectWriteComponent {
73 pub fn new(bitmap_factory: &IWICImagingFactory) -> Result<Self> {
74 unsafe {
75 let factory: IDWriteFactory5 = DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED)?;
76 let bitmap_factory = AgileReference::new(bitmap_factory)?;
77 let d2d1_factory: ID2D1Factory =
78 D2D1CreateFactory(D2D1_FACTORY_TYPE_MULTI_THREADED, None)?;
79 // The `IDWriteInMemoryFontFileLoader` here is supported starting from
80 // Windows 10 Creators Update, which consequently requires the entire
81 // `DirectWriteTextSystem` to run on `win10 1703`+.
82 let in_memory_loader = factory.CreateInMemoryFontFileLoader()?;
83 factory.RegisterFontFileLoader(&in_memory_loader)?;
84 let builder = factory.CreateFontSetBuilder()?;
85 let mut locale_vec = vec![0u16; LOCALE_NAME_MAX_LENGTH as usize];
86 GetUserDefaultLocaleName(&mut locale_vec);
87 let locale = String::from_utf16_lossy(&locale_vec);
88 let text_renderer = Arc::new(TextRendererWrapper::new(&locale));
89 let render_context = GlyphRenderContext::new(&factory, &d2d1_factory)?;
90
91 Ok(DirectWriteComponent {
92 locale,
93 factory,
94 bitmap_factory,
95 d2d1_factory,
96 in_memory_loader,
97 builder,
98 text_renderer,
99 render_context,
100 })
101 }
102 }
103}
104
105impl GlyphRenderContext {
106 pub fn new(factory: &IDWriteFactory5, d2d1_factory: &ID2D1Factory) -> Result<Self> {
107 unsafe {
108 let default_params: IDWriteRenderingParams3 =
109 factory.CreateRenderingParams()?.cast()?;
110 let gamma = default_params.GetGamma();
111 let enhanced_contrast = default_params.GetEnhancedContrast();
112 let gray_contrast = default_params.GetGrayscaleEnhancedContrast();
113 let cleartype_level = default_params.GetClearTypeLevel();
114 let grid_fit_mode = default_params.GetGridFitMode();
115
116 let params = factory.CreateCustomRenderingParams(
117 gamma,
118 enhanced_contrast,
119 gray_contrast,
120 cleartype_level,
121 DWRITE_PIXEL_GEOMETRY_RGB,
122 DWRITE_RENDERING_MODE1_NATURAL_SYMMETRIC,
123 grid_fit_mode,
124 )?;
125 let dc_target = {
126 let target = d2d1_factory.CreateDCRenderTarget(&get_render_target_property(
127 DXGI_FORMAT_B8G8R8A8_UNORM,
128 D2D1_ALPHA_MODE_PREMULTIPLIED,
129 ))?;
130 let target = target.cast::<ID2D1DeviceContext4>()?;
131 target.SetTextRenderingParams(¶ms);
132 target
133 };
134
135 Ok(Self { params, dc_target })
136 }
137 }
138}
139
140impl DirectWriteTextSystem {
141 pub(crate) fn new(bitmap_factory: &IWICImagingFactory) -> Result<Self> {
142 let components = DirectWriteComponent::new(bitmap_factory)?;
143 let system_font_collection = unsafe {
144 let mut result = std::mem::zeroed();
145 components
146 .factory
147 .GetSystemFontCollection(false, &mut result, true)?;
148 result.unwrap()
149 };
150 let custom_font_set = unsafe { components.builder.CreateFontSet()? };
151 let custom_font_collection = unsafe {
152 components
153 .factory
154 .CreateFontCollectionFromFontSet(&custom_font_set)?
155 };
156 let system_ui_font_name = get_system_ui_font_name();
157
158 Ok(Self(RwLock::new(DirectWriteState {
159 components,
160 system_ui_font_name,
161 system_font_collection,
162 custom_font_collection,
163 fonts: Vec::new(),
164 font_selections: HashMap::default(),
165 font_id_by_identifier: HashMap::default(),
166 })))
167 }
168}
169
170impl PlatformTextSystem for DirectWriteTextSystem {
171 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
172 self.0.write().add_fonts(fonts)
173 }
174
175 fn all_font_names(&self) -> Vec<String> {
176 self.0.read().all_font_names()
177 }
178
179 fn font_id(&self, font: &Font) -> Result<FontId> {
180 let lock = self.0.upgradable_read();
181 if let Some(font_id) = lock.font_selections.get(font) {
182 Ok(*font_id)
183 } else {
184 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
185 let font_id = lock.select_font(font);
186 lock.font_selections.insert(font.clone(), font_id);
187 Ok(font_id)
188 }
189 }
190
191 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
192 self.0.read().font_metrics(font_id)
193 }
194
195 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
196 self.0.read().get_typographic_bounds(font_id, glyph_id)
197 }
198
199 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> anyhow::Result<Size<f32>> {
200 self.0.read().get_advance(font_id, glyph_id)
201 }
202
203 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
204 self.0.read().glyph_for_char(font_id, ch)
205 }
206
207 fn glyph_raster_bounds(
208 &self,
209 params: &RenderGlyphParams,
210 ) -> anyhow::Result<Bounds<DevicePixels>> {
211 self.0.read().raster_bounds(params)
212 }
213
214 fn rasterize_glyph(
215 &self,
216 params: &RenderGlyphParams,
217 raster_bounds: Bounds<DevicePixels>,
218 ) -> anyhow::Result<(Size<DevicePixels>, Vec<u8>)> {
219 self.0.read().rasterize_glyph(params, raster_bounds)
220 }
221
222 fn layout_line(&self, text: &str, font_size: Pixels, runs: &[FontRun]) -> LineLayout {
223 self.0
224 .write()
225 .layout_line(text, font_size, runs)
226 .log_err()
227 .unwrap_or(LineLayout {
228 font_size,
229 ..Default::default()
230 })
231 }
232}
233
234impl DirectWriteState {
235 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
236 for font_data in fonts {
237 match font_data {
238 Cow::Borrowed(data) => unsafe {
239 let font_file = self
240 .components
241 .in_memory_loader
242 .CreateInMemoryFontFileReference(
243 &self.components.factory,
244 data.as_ptr() as _,
245 data.len() as _,
246 None,
247 )?;
248 self.components.builder.AddFontFile(&font_file)?;
249 },
250 Cow::Owned(data) => unsafe {
251 let font_file = self
252 .components
253 .in_memory_loader
254 .CreateInMemoryFontFileReference(
255 &self.components.factory,
256 data.as_ptr() as _,
257 data.len() as _,
258 None,
259 )?;
260 self.components.builder.AddFontFile(&font_file)?;
261 },
262 }
263 }
264 let set = unsafe { self.components.builder.CreateFontSet()? };
265 let collection = unsafe {
266 self.components
267 .factory
268 .CreateFontCollectionFromFontSet(&set)?
269 };
270 self.custom_font_collection = collection;
271
272 Ok(())
273 }
274
275 fn generate_font_fallbacks(
276 &self,
277 fallbacks: &FontFallbacks,
278 ) -> Result<Option<IDWriteFontFallback>> {
279 if fallbacks.fallback_list().is_empty() {
280 return Ok(None);
281 }
282 unsafe {
283 let builder = self.components.factory.CreateFontFallbackBuilder()?;
284 let font_set = &self.system_font_collection.GetFontSet()?;
285 for family_name in fallbacks.fallback_list() {
286 let Some(fonts) = font_set
287 .GetMatchingFonts(
288 &HSTRING::from(family_name),
289 DWRITE_FONT_WEIGHT_NORMAL,
290 DWRITE_FONT_STRETCH_NORMAL,
291 DWRITE_FONT_STYLE_NORMAL,
292 )
293 .log_err()
294 else {
295 continue;
296 };
297 if fonts.GetFontCount() == 0 {
298 log::error!("No matching font found for {}", family_name);
299 continue;
300 }
301 let font = fonts.GetFontFaceReference(0)?.CreateFontFace()?;
302 let mut count = 0;
303 font.GetUnicodeRanges(None, &mut count).ok();
304 if count == 0 {
305 continue;
306 }
307 let mut unicode_ranges = vec![DWRITE_UNICODE_RANGE::default(); count as usize];
308 let Some(_) = font
309 .GetUnicodeRanges(Some(&mut unicode_ranges), &mut count)
310 .log_err()
311 else {
312 continue;
313 };
314 let target_family_name = HSTRING::from(family_name);
315 builder.AddMapping(
316 &unicode_ranges,
317 &[target_family_name.as_ptr()],
318 None,
319 None,
320 None,
321 1.0,
322 )?;
323 }
324 let system_fallbacks = self.components.factory.GetSystemFontFallback()?;
325 builder.AddMappings(&system_fallbacks)?;
326 Ok(Some(builder.CreateFontFallback()?))
327 }
328 }
329
330 unsafe fn generate_font_features(
331 &self,
332 font_features: &FontFeatures,
333 ) -> Result<IDWriteTypography> {
334 let direct_write_features = unsafe { self.components.factory.CreateTypography()? };
335 apply_font_features(&direct_write_features, font_features)?;
336 Ok(direct_write_features)
337 }
338
339 unsafe fn get_font_id_from_font_collection(
340 &mut self,
341 family_name: &str,
342 font_weight: FontWeight,
343 font_style: FontStyle,
344 font_features: &FontFeatures,
345 font_fallbacks: Option<&FontFallbacks>,
346 is_system_font: bool,
347 ) -> Option<FontId> {
348 let collection = if is_system_font {
349 &self.system_font_collection
350 } else {
351 &self.custom_font_collection
352 };
353 let fontset = unsafe { collection.GetFontSet().log_err()? };
354 let font = unsafe {
355 fontset
356 .GetMatchingFonts(
357 &HSTRING::from(family_name),
358 font_weight.into(),
359 DWRITE_FONT_STRETCH_NORMAL,
360 font_style.into(),
361 )
362 .log_err()?
363 };
364 let total_number = unsafe { font.GetFontCount() };
365 for index in 0..total_number {
366 let Some(font_face_ref) = (unsafe { font.GetFontFaceReference(index).log_err() })
367 else {
368 continue;
369 };
370 let Some(font_face) = (unsafe { font_face_ref.CreateFontFace().log_err() }) else {
371 continue;
372 };
373 let Some(identifier) = get_font_identifier(&font_face, &self.components.locale) else {
374 continue;
375 };
376 let Some(direct_write_features) =
377 (unsafe { self.generate_font_features(font_features).log_err() })
378 else {
379 continue;
380 };
381 let fallbacks = font_fallbacks
382 .and_then(|fallbacks| self.generate_font_fallbacks(fallbacks).log_err().flatten());
383 let font_info = FontInfo {
384 font_family: family_name.to_owned(),
385 font_face,
386 features: direct_write_features,
387 fallbacks,
388 is_system_font,
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 = unsafe { std::mem::zeroed() };
400 if unsafe {
401 self.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 unsafe {
465 self.get_font_id_from_font_collection(
466 family_name,
467 weight,
468 style,
469 features,
470 fallbacks,
471 false,
472 )
473 .or_else(|| {
474 self.get_font_id_from_font_collection(
475 family_name,
476 weight,
477 style,
478 features,
479 fallbacks,
480 true,
481 )
482 })
483 .or_else(|| {
484 self.update_system_font_collection();
485 self.get_font_id_from_font_collection(
486 family_name,
487 weight,
488 style,
489 features,
490 fallbacks,
491 true,
492 )
493 })
494 }
495 }
496
497 fn layout_line(
498 &mut self,
499 text: &str,
500 font_size: Pixels,
501 font_runs: &[FontRun],
502 ) -> Result<LineLayout> {
503 if font_runs.is_empty() {
504 return Ok(LineLayout {
505 font_size,
506 ..Default::default()
507 });
508 }
509 unsafe {
510 let text_renderer = self.components.text_renderer.clone();
511 let text_wide = text.encode_utf16().collect_vec();
512
513 let mut utf8_offset = 0usize;
514 let mut utf16_offset = 0u32;
515 let text_layout = {
516 let first_run = &font_runs[0];
517 let font_info = &self.fonts[first_run.font_id.0];
518 let collection = if font_info.is_system_font {
519 &self.system_font_collection
520 } else {
521 &self.custom_font_collection
522 };
523 let format: IDWriteTextFormat1 = self
524 .components
525 .factory
526 .CreateTextFormat(
527 &HSTRING::from(&font_info.font_family),
528 collection,
529 font_info.font_face.GetWeight(),
530 font_info.font_face.GetStyle(),
531 DWRITE_FONT_STRETCH_NORMAL,
532 font_size.0,
533 &HSTRING::from(&self.components.locale),
534 )?
535 .cast()?;
536 if let Some(ref fallbacks) = font_info.fallbacks {
537 format.SetFontFallback(fallbacks)?;
538 }
539
540 let layout = self.components.factory.CreateTextLayout(
541 &text_wide,
542 &format,
543 f32::INFINITY,
544 f32::INFINITY,
545 )?;
546 let current_text = &text[utf8_offset..(utf8_offset + first_run.len)];
547 utf8_offset += first_run.len;
548 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
549 let text_range = DWRITE_TEXT_RANGE {
550 startPosition: utf16_offset,
551 length: current_text_utf16_length,
552 };
553 layout.SetTypography(&font_info.features, text_range)?;
554 utf16_offset += current_text_utf16_length;
555
556 layout
557 };
558
559 let mut first_run = true;
560 let mut ascent = Pixels::default();
561 let mut descent = Pixels::default();
562 for run in font_runs {
563 if first_run {
564 first_run = false;
565 let mut metrics = vec![DWRITE_LINE_METRICS::default(); 4];
566 let mut line_count = 0u32;
567 text_layout.GetLineMetrics(Some(&mut metrics), &mut line_count as _)?;
568 ascent = px(metrics[0].baseline);
569 descent = px(metrics[0].height - metrics[0].baseline);
570 continue;
571 }
572 let font_info = &self.fonts[run.font_id.0];
573 let current_text = &text[utf8_offset..(utf8_offset + run.len)];
574 utf8_offset += run.len;
575 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
576
577 let collection = if font_info.is_system_font {
578 &self.system_font_collection
579 } else {
580 &self.custom_font_collection
581 };
582 let text_range = DWRITE_TEXT_RANGE {
583 startPosition: utf16_offset,
584 length: current_text_utf16_length,
585 };
586 utf16_offset += current_text_utf16_length;
587 text_layout.SetFontCollection(collection, text_range)?;
588 text_layout
589 .SetFontFamilyName(&HSTRING::from(&font_info.font_family), text_range)?;
590 text_layout.SetFontSize(font_size.0, text_range)?;
591 text_layout.SetFontStyle(font_info.font_face.GetStyle(), text_range)?;
592 text_layout.SetFontWeight(font_info.font_face.GetWeight(), text_range)?;
593 text_layout.SetTypography(&font_info.features, text_range)?;
594 }
595
596 let mut runs = Vec::new();
597 let renderer_context = RendererContext {
598 text_system: self,
599 index_converter: StringIndexConverter::new(text),
600 runs: &mut runs,
601 utf16_index: 0,
602 width: 0.0,
603 };
604 text_layout.Draw(
605 Some(&renderer_context as *const _ as _),
606 &text_renderer.0,
607 0.0,
608 0.0,
609 )?;
610 let width = px(renderer_context.width);
611
612 Ok(LineLayout {
613 font_size,
614 width,
615 ascent,
616 descent,
617 runs,
618 len: text.len(),
619 })
620 }
621 }
622
623 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
624 unsafe {
625 let font_info = &self.fonts[font_id.0];
626 let mut metrics = std::mem::zeroed();
627 font_info.font_face.GetMetrics(&mut metrics);
628
629 FontMetrics {
630 units_per_em: metrics.Base.designUnitsPerEm as _,
631 ascent: metrics.Base.ascent as _,
632 descent: -(metrics.Base.descent as f32),
633 line_gap: metrics.Base.lineGap as _,
634 underline_position: metrics.Base.underlinePosition as _,
635 underline_thickness: metrics.Base.underlineThickness as _,
636 cap_height: metrics.Base.capHeight as _,
637 x_height: metrics.Base.xHeight as _,
638 bounding_box: Bounds {
639 origin: Point {
640 x: metrics.glyphBoxLeft as _,
641 y: metrics.glyphBoxBottom as _,
642 },
643 size: Size {
644 width: (metrics.glyphBoxRight - metrics.glyphBoxLeft) as _,
645 height: (metrics.glyphBoxTop - metrics.glyphBoxBottom) as _,
646 },
647 },
648 }
649 }
650 }
651
652 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
653 let render_target = &self.components.render_context.dc_target;
654 unsafe {
655 render_target.SetUnitMode(D2D1_UNIT_MODE_DIPS);
656 render_target.SetDpi(96.0 * params.scale_factor, 96.0 * params.scale_factor);
657 }
658 let font = &self.fonts[params.font_id.0];
659 let glyph_id = [params.glyph_id.0 as u16];
660 let advance = [0.0f32];
661 let offset = [DWRITE_GLYPH_OFFSET::default()];
662 let glyph_run = DWRITE_GLYPH_RUN {
663 fontFace: unsafe { std::mem::transmute_copy(&font.font_face) },
664 fontEmSize: params.font_size.0,
665 glyphCount: 1,
666 glyphIndices: glyph_id.as_ptr(),
667 glyphAdvances: advance.as_ptr(),
668 glyphOffsets: offset.as_ptr(),
669 isSideways: BOOL(0),
670 bidiLevel: 0,
671 };
672 let bounds = unsafe {
673 render_target.GetGlyphRunWorldBounds(
674 Vector2 { X: 0.0, Y: 0.0 },
675 &glyph_run,
676 DWRITE_MEASURING_MODE_NATURAL,
677 )?
678 };
679 // todo(windows)
680 // This is a walkaround, deleted when figured out.
681 let y_offset;
682 let extra_height;
683 if params.is_emoji {
684 y_offset = 0;
685 extra_height = 0;
686 } else {
687 // make some room for scaler.
688 y_offset = -1;
689 extra_height = 2;
690 }
691
692 if bounds.right < bounds.left {
693 Ok(Bounds {
694 origin: point(0.into(), 0.into()),
695 size: size(0.into(), 0.into()),
696 })
697 } else {
698 Ok(Bounds {
699 origin: point(
700 ((bounds.left * params.scale_factor).ceil() as i32).into(),
701 ((bounds.top * params.scale_factor).ceil() as i32 + y_offset).into(),
702 ),
703 size: size(
704 (((bounds.right - bounds.left) * params.scale_factor).ceil() as i32).into(),
705 (((bounds.bottom - bounds.top) * params.scale_factor).ceil() as i32
706 + extra_height)
707 .into(),
708 ),
709 })
710 }
711 }
712
713 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
714 let font_info = &self.fonts[font_id.0];
715 let codepoints = [ch as u32];
716 let mut glyph_indices = vec![0u16; 1];
717 unsafe {
718 font_info
719 .font_face
720 .GetGlyphIndices(codepoints.as_ptr(), 1, glyph_indices.as_mut_ptr())
721 .log_err()
722 }
723 .map(|_| GlyphId(glyph_indices[0] as u32))
724 }
725
726 fn rasterize_glyph(
727 &self,
728 params: &RenderGlyphParams,
729 glyph_bounds: Bounds<DevicePixels>,
730 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
731 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
732 anyhow::bail!("glyph bounds are empty");
733 }
734
735 let font_info = &self.fonts[params.font_id.0];
736 let glyph_id = [params.glyph_id.0 as u16];
737 let advance = [glyph_bounds.size.width.0 as f32];
738 let offset = [DWRITE_GLYPH_OFFSET {
739 advanceOffset: -glyph_bounds.origin.x.0 as f32 / params.scale_factor,
740 ascenderOffset: glyph_bounds.origin.y.0 as f32 / params.scale_factor,
741 }];
742 let glyph_run = DWRITE_GLYPH_RUN {
743 fontFace: unsafe { std::mem::transmute_copy(&font_info.font_face) },
744 fontEmSize: params.font_size.0,
745 glyphCount: 1,
746 glyphIndices: glyph_id.as_ptr(),
747 glyphAdvances: advance.as_ptr(),
748 glyphOffsets: offset.as_ptr(),
749 isSideways: BOOL(0),
750 bidiLevel: 0,
751 };
752
753 // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing.
754 let mut bitmap_size = glyph_bounds.size;
755 if params.subpixel_variant.x > 0 {
756 bitmap_size.width += DevicePixels(1);
757 }
758 if params.subpixel_variant.y > 0 {
759 bitmap_size.height += DevicePixels(1);
760 }
761 let bitmap_size = bitmap_size;
762
763 let total_bytes;
764 let bitmap_format;
765 let render_target_property;
766 let bitmap_width;
767 let bitmap_height;
768 let bitmap_stride;
769 let bitmap_dpi;
770 if params.is_emoji {
771 total_bytes = bitmap_size.height.0 as usize * bitmap_size.width.0 as usize * 4;
772 bitmap_format = &GUID_WICPixelFormat32bppPBGRA;
773 render_target_property = get_render_target_property(
774 DXGI_FORMAT_B8G8R8A8_UNORM,
775 D2D1_ALPHA_MODE_PREMULTIPLIED,
776 );
777 bitmap_width = bitmap_size.width.0 as u32;
778 bitmap_height = bitmap_size.height.0 as u32;
779 bitmap_stride = bitmap_size.width.0 as u32 * 4;
780 bitmap_dpi = 96.0;
781 } else {
782 total_bytes = bitmap_size.height.0 as usize * bitmap_size.width.0 as usize;
783 bitmap_format = &GUID_WICPixelFormat8bppAlpha;
784 render_target_property =
785 get_render_target_property(DXGI_FORMAT_A8_UNORM, D2D1_ALPHA_MODE_STRAIGHT);
786 bitmap_width = bitmap_size.width.0 as u32 * 2;
787 bitmap_height = bitmap_size.height.0 as u32 * 2;
788 bitmap_stride = bitmap_size.width.0 as u32;
789 bitmap_dpi = 192.0;
790 }
791
792 let bitmap_factory = self.components.bitmap_factory.resolve()?;
793 unsafe {
794 let bitmap = bitmap_factory.CreateBitmap(
795 bitmap_width,
796 bitmap_height,
797 bitmap_format,
798 WICBitmapCacheOnLoad,
799 )?;
800 let render_target = self
801 .components
802 .d2d1_factory
803 .CreateWicBitmapRenderTarget(&bitmap, &render_target_property)?;
804 let brush = render_target.CreateSolidColorBrush(&BRUSH_COLOR, None)?;
805 let subpixel_shift = params
806 .subpixel_variant
807 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
808 let baseline_origin = Vector2 {
809 X: subpixel_shift.x / params.scale_factor,
810 Y: subpixel_shift.y / params.scale_factor,
811 };
812
813 // This `cast()` action here should never fail since we are running on Win10+, and
814 // ID2D1DeviceContext4 requires Win8+
815 let render_target = render_target.cast::<ID2D1DeviceContext4>().unwrap();
816 render_target.SetUnitMode(D2D1_UNIT_MODE_DIPS);
817 render_target.SetDpi(
818 bitmap_dpi * params.scale_factor,
819 bitmap_dpi * params.scale_factor,
820 );
821 render_target.SetTextRenderingParams(&self.components.render_context.params);
822 render_target.BeginDraw();
823
824 if params.is_emoji {
825 // WARN: only DWRITE_GLYPH_IMAGE_FORMATS_COLR has been tested
826 let enumerator = self.components.factory.TranslateColorGlyphRun(
827 baseline_origin,
828 &glyph_run as _,
829 None,
830 DWRITE_GLYPH_IMAGE_FORMATS_COLR
831 | DWRITE_GLYPH_IMAGE_FORMATS_SVG
832 | DWRITE_GLYPH_IMAGE_FORMATS_PNG
833 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
834 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8,
835 DWRITE_MEASURING_MODE_NATURAL,
836 None,
837 0,
838 )?;
839 while enumerator.MoveNext().is_ok() {
840 let Ok(color_glyph) = enumerator.GetCurrentRun() else {
841 break;
842 };
843 let color_glyph = &*color_glyph;
844 let brush_color = translate_color(&color_glyph.Base.runColor);
845 brush.SetColor(&brush_color);
846 match color_glyph.glyphImageFormat {
847 DWRITE_GLYPH_IMAGE_FORMATS_PNG
848 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
849 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8 => render_target
850 .DrawColorBitmapGlyphRun(
851 color_glyph.glyphImageFormat,
852 baseline_origin,
853 &color_glyph.Base.glyphRun,
854 color_glyph.measuringMode,
855 D2D1_COLOR_BITMAP_GLYPH_SNAP_OPTION_DEFAULT,
856 ),
857 DWRITE_GLYPH_IMAGE_FORMATS_SVG => render_target.DrawSvgGlyphRun(
858 baseline_origin,
859 &color_glyph.Base.glyphRun,
860 &brush,
861 None,
862 color_glyph.Base.paletteIndex as u32,
863 color_glyph.measuringMode,
864 ),
865 _ => render_target.DrawGlyphRun(
866 baseline_origin,
867 &color_glyph.Base.glyphRun,
868 Some(color_glyph.Base.glyphRunDescription as *const _),
869 &brush,
870 color_glyph.measuringMode,
871 ),
872 }
873 }
874 } else {
875 render_target.DrawGlyphRun(
876 baseline_origin,
877 &glyph_run,
878 None,
879 &brush,
880 DWRITE_MEASURING_MODE_NATURAL,
881 );
882 }
883 render_target.EndDraw(None, None)?;
884
885 let mut raw_data = vec![0u8; total_bytes];
886 if params.is_emoji {
887 bitmap.CopyPixels(std::ptr::null() as _, bitmap_stride, &mut raw_data)?;
888 // Convert from BGRA with premultiplied alpha to BGRA with straight alpha.
889 for pixel in raw_data.chunks_exact_mut(4) {
890 let a = pixel[3] as f32 / 255.;
891 pixel[0] = (pixel[0] as f32 / a) as u8;
892 pixel[1] = (pixel[1] as f32 / a) as u8;
893 pixel[2] = (pixel[2] as f32 / a) as u8;
894 }
895 } else {
896 let scaler = bitmap_factory.CreateBitmapScaler()?;
897 scaler.Initialize(
898 &bitmap,
899 bitmap_size.width.0 as u32,
900 bitmap_size.height.0 as u32,
901 WICBitmapInterpolationModeHighQualityCubic,
902 )?;
903 scaler.CopyPixels(std::ptr::null() as _, bitmap_stride, &mut raw_data)?;
904 }
905 Ok((bitmap_size, raw_data))
906 }
907 }
908
909 fn get_typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
910 unsafe {
911 let font = &self.fonts[font_id.0].font_face;
912 let glyph_indices = [glyph_id.0 as u16];
913 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
914 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
915
916 let metrics = &metrics[0];
917 let advance_width = metrics.advanceWidth as i32;
918 let advance_height = metrics.advanceHeight as i32;
919 let left_side_bearing = metrics.leftSideBearing;
920 let right_side_bearing = metrics.rightSideBearing;
921 let top_side_bearing = metrics.topSideBearing;
922 let bottom_side_bearing = metrics.bottomSideBearing;
923 let vertical_origin_y = metrics.verticalOriginY;
924
925 let y_offset = vertical_origin_y + bottom_side_bearing - advance_height;
926 let width = advance_width - (left_side_bearing + right_side_bearing);
927 let height = advance_height - (top_side_bearing + bottom_side_bearing);
928
929 Ok(Bounds {
930 origin: Point {
931 x: left_side_bearing as f32,
932 y: y_offset as f32,
933 },
934 size: Size {
935 width: width as f32,
936 height: height as f32,
937 },
938 })
939 }
940 }
941
942 fn get_advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
943 unsafe {
944 let font = &self.fonts[font_id.0].font_face;
945 let glyph_indices = [glyph_id.0 as u16];
946 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
947 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
948
949 let metrics = &metrics[0];
950
951 Ok(Size {
952 width: metrics.advanceWidth as f32,
953 height: 0.0,
954 })
955 }
956 }
957
958 fn all_font_names(&self) -> Vec<String> {
959 let mut result =
960 get_font_names_from_collection(&self.system_font_collection, &self.components.locale);
961 result.extend(get_font_names_from_collection(
962 &self.custom_font_collection,
963 &self.components.locale,
964 ));
965 result
966 }
967}
968
969impl Drop for DirectWriteState {
970 fn drop(&mut self) {
971 unsafe {
972 let _ = self
973 .components
974 .factory
975 .UnregisterFontFileLoader(&self.components.in_memory_loader);
976 }
977 }
978}
979
980struct TextRendererWrapper(pub IDWriteTextRenderer);
981
982impl TextRendererWrapper {
983 pub fn new(locale_str: &str) -> Self {
984 let inner = TextRenderer::new(locale_str);
985 TextRendererWrapper(inner.into())
986 }
987}
988
989#[implement(IDWriteTextRenderer)]
990struct TextRenderer {
991 locale: String,
992}
993
994impl TextRenderer {
995 pub fn new(locale_str: &str) -> Self {
996 TextRenderer {
997 locale: locale_str.to_owned(),
998 }
999 }
1000}
1001
1002struct RendererContext<'t, 'a, 'b> {
1003 text_system: &'t mut DirectWriteState,
1004 index_converter: StringIndexConverter<'a>,
1005 runs: &'b mut Vec<ShapedRun>,
1006 utf16_index: usize,
1007 width: f32,
1008}
1009
1010#[allow(non_snake_case)]
1011impl IDWritePixelSnapping_Impl for TextRenderer_Impl {
1012 fn IsPixelSnappingDisabled(
1013 &self,
1014 _clientdrawingcontext: *const ::core::ffi::c_void,
1015 ) -> windows::core::Result<BOOL> {
1016 Ok(BOOL(0))
1017 }
1018
1019 fn GetCurrentTransform(
1020 &self,
1021 _clientdrawingcontext: *const ::core::ffi::c_void,
1022 transform: *mut DWRITE_MATRIX,
1023 ) -> windows::core::Result<()> {
1024 unsafe {
1025 *transform = DWRITE_MATRIX {
1026 m11: 1.0,
1027 m12: 0.0,
1028 m21: 0.0,
1029 m22: 1.0,
1030 dx: 0.0,
1031 dy: 0.0,
1032 };
1033 }
1034 Ok(())
1035 }
1036
1037 fn GetPixelsPerDip(
1038 &self,
1039 _clientdrawingcontext: *const ::core::ffi::c_void,
1040 ) -> windows::core::Result<f32> {
1041 Ok(1.0)
1042 }
1043}
1044
1045#[allow(non_snake_case)]
1046impl IDWriteTextRenderer_Impl for TextRenderer_Impl {
1047 fn DrawGlyphRun(
1048 &self,
1049 clientdrawingcontext: *const ::core::ffi::c_void,
1050 _baselineoriginx: f32,
1051 _baselineoriginy: f32,
1052 _measuringmode: DWRITE_MEASURING_MODE,
1053 glyphrun: *const DWRITE_GLYPH_RUN,
1054 glyphrundescription: *const DWRITE_GLYPH_RUN_DESCRIPTION,
1055 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1056 ) -> windows::core::Result<()> {
1057 unsafe {
1058 let glyphrun = &*glyphrun;
1059 let glyph_count = glyphrun.glyphCount as usize;
1060 if glyph_count == 0 {
1061 return Ok(());
1062 }
1063 let desc = &*glyphrundescription;
1064 let utf16_length_per_glyph = desc.stringLength as usize / glyph_count;
1065 let context =
1066 &mut *(clientdrawingcontext as *const RendererContext as *mut RendererContext);
1067
1068 if glyphrun.fontFace.is_none() {
1069 return Ok(());
1070 }
1071
1072 let font_face = glyphrun.fontFace.as_ref().unwrap();
1073 // This `cast()` action here should never fail since we are running on Win10+, and
1074 // `IDWriteFontFace3` requires Win10
1075 let font_face = &font_face.cast::<IDWriteFontFace3>().unwrap();
1076 let Some((font_identifier, font_struct, color_font)) =
1077 get_font_identifier_and_font_struct(font_face, &self.locale)
1078 else {
1079 return Ok(());
1080 };
1081
1082 let font_id = if let Some(id) = context
1083 .text_system
1084 .font_id_by_identifier
1085 .get(&font_identifier)
1086 {
1087 *id
1088 } else {
1089 context.text_system.select_font(&font_struct)
1090 };
1091 let mut glyphs = Vec::with_capacity(glyph_count);
1092 for index in 0..glyph_count {
1093 let id = GlyphId(*glyphrun.glyphIndices.add(index) as u32);
1094 context
1095 .index_converter
1096 .advance_to_utf16_ix(context.utf16_index);
1097 let is_emoji = color_font
1098 && is_color_glyph(font_face, id, &context.text_system.components.factory);
1099 glyphs.push(ShapedGlyph {
1100 id,
1101 position: point(px(context.width), px(0.0)),
1102 index: context.index_converter.utf8_ix,
1103 is_emoji,
1104 });
1105 context.utf16_index += utf16_length_per_glyph;
1106 context.width += *glyphrun.glyphAdvances.add(index);
1107 }
1108 context.runs.push(ShapedRun { font_id, glyphs });
1109 }
1110 Ok(())
1111 }
1112
1113 fn DrawUnderline(
1114 &self,
1115 _clientdrawingcontext: *const ::core::ffi::c_void,
1116 _baselineoriginx: f32,
1117 _baselineoriginy: f32,
1118 _underline: *const DWRITE_UNDERLINE,
1119 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1120 ) -> windows::core::Result<()> {
1121 Err(windows::core::Error::new(
1122 E_NOTIMPL,
1123 "DrawUnderline unimplemented",
1124 ))
1125 }
1126
1127 fn DrawStrikethrough(
1128 &self,
1129 _clientdrawingcontext: *const ::core::ffi::c_void,
1130 _baselineoriginx: f32,
1131 _baselineoriginy: f32,
1132 _strikethrough: *const DWRITE_STRIKETHROUGH,
1133 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1134 ) -> windows::core::Result<()> {
1135 Err(windows::core::Error::new(
1136 E_NOTIMPL,
1137 "DrawStrikethrough unimplemented",
1138 ))
1139 }
1140
1141 fn DrawInlineObject(
1142 &self,
1143 _clientdrawingcontext: *const ::core::ffi::c_void,
1144 _originx: f32,
1145 _originy: f32,
1146 _inlineobject: windows::core::Ref<IDWriteInlineObject>,
1147 _issideways: BOOL,
1148 _isrighttoleft: BOOL,
1149 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1150 ) -> windows::core::Result<()> {
1151 Err(windows::core::Error::new(
1152 E_NOTIMPL,
1153 "DrawInlineObject unimplemented",
1154 ))
1155 }
1156}
1157
1158struct StringIndexConverter<'a> {
1159 text: &'a str,
1160 utf8_ix: usize,
1161 utf16_ix: usize,
1162}
1163
1164impl<'a> StringIndexConverter<'a> {
1165 fn new(text: &'a str) -> Self {
1166 Self {
1167 text,
1168 utf8_ix: 0,
1169 utf16_ix: 0,
1170 }
1171 }
1172
1173 #[allow(dead_code)]
1174 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
1175 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1176 if self.utf8_ix + ix >= utf8_target {
1177 self.utf8_ix += ix;
1178 return;
1179 }
1180 self.utf16_ix += c.len_utf16();
1181 }
1182 self.utf8_ix = self.text.len();
1183 }
1184
1185 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
1186 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1187 if self.utf16_ix >= utf16_target {
1188 self.utf8_ix += ix;
1189 return;
1190 }
1191 self.utf16_ix += c.len_utf16();
1192 }
1193 self.utf8_ix = self.text.len();
1194 }
1195}
1196
1197impl Into<DWRITE_FONT_STYLE> for FontStyle {
1198 fn into(self) -> DWRITE_FONT_STYLE {
1199 match self {
1200 FontStyle::Normal => DWRITE_FONT_STYLE_NORMAL,
1201 FontStyle::Italic => DWRITE_FONT_STYLE_ITALIC,
1202 FontStyle::Oblique => DWRITE_FONT_STYLE_OBLIQUE,
1203 }
1204 }
1205}
1206
1207impl From<DWRITE_FONT_STYLE> for FontStyle {
1208 fn from(value: DWRITE_FONT_STYLE) -> Self {
1209 match value.0 {
1210 0 => FontStyle::Normal,
1211 1 => FontStyle::Italic,
1212 2 => FontStyle::Oblique,
1213 _ => unreachable!(),
1214 }
1215 }
1216}
1217
1218impl Into<DWRITE_FONT_WEIGHT> for FontWeight {
1219 fn into(self) -> DWRITE_FONT_WEIGHT {
1220 DWRITE_FONT_WEIGHT(self.0 as i32)
1221 }
1222}
1223
1224impl From<DWRITE_FONT_WEIGHT> for FontWeight {
1225 fn from(value: DWRITE_FONT_WEIGHT) -> Self {
1226 FontWeight(value.0 as f32)
1227 }
1228}
1229
1230fn get_font_names_from_collection(
1231 collection: &IDWriteFontCollection1,
1232 locale: &str,
1233) -> Vec<String> {
1234 unsafe {
1235 let mut result = Vec::new();
1236 let family_count = collection.GetFontFamilyCount();
1237 for index in 0..family_count {
1238 let Some(font_family) = collection.GetFontFamily(index).log_err() else {
1239 continue;
1240 };
1241 let Some(localized_family_name) = font_family.GetFamilyNames().log_err() else {
1242 continue;
1243 };
1244 let Some(family_name) = get_name(localized_family_name, locale).log_err() else {
1245 continue;
1246 };
1247 result.push(family_name);
1248 }
1249
1250 result
1251 }
1252}
1253
1254fn get_font_identifier_and_font_struct(
1255 font_face: &IDWriteFontFace3,
1256 locale: &str,
1257) -> Option<(FontIdentifier, Font, bool)> {
1258 let postscript_name = get_postscript_name(font_face, locale).log_err()?;
1259 let localized_family_name = unsafe { font_face.GetFamilyNames().log_err() }?;
1260 let family_name = get_name(localized_family_name, locale).log_err()?;
1261 let weight = unsafe { font_face.GetWeight() };
1262 let style = unsafe { font_face.GetStyle() };
1263 let identifier = FontIdentifier {
1264 postscript_name,
1265 weight: weight.0,
1266 style: style.0,
1267 };
1268 let font_struct = Font {
1269 family: family_name.into(),
1270 features: FontFeatures::default(),
1271 weight: weight.into(),
1272 style: style.into(),
1273 fallbacks: None,
1274 };
1275 let is_emoji = unsafe { font_face.IsColorFont().as_bool() };
1276 Some((identifier, font_struct, is_emoji))
1277}
1278
1279#[inline]
1280fn get_font_identifier(font_face: &IDWriteFontFace3, locale: &str) -> Option<FontIdentifier> {
1281 let weight = unsafe { font_face.GetWeight().0 };
1282 let style = unsafe { font_face.GetStyle().0 };
1283 get_postscript_name(font_face, locale)
1284 .log_err()
1285 .map(|postscript_name| FontIdentifier {
1286 postscript_name,
1287 weight,
1288 style,
1289 })
1290}
1291
1292#[inline]
1293fn get_postscript_name(font_face: &IDWriteFontFace3, locale: &str) -> Result<String> {
1294 let mut info = None;
1295 let mut exists = BOOL(0);
1296 unsafe {
1297 font_face.GetInformationalStrings(
1298 DWRITE_INFORMATIONAL_STRING_POSTSCRIPT_NAME,
1299 &mut info,
1300 &mut exists,
1301 )?
1302 };
1303 if !exists.as_bool() || info.is_none() {
1304 anyhow::bail!("No postscript name found for font face");
1305 }
1306
1307 get_name(info.unwrap(), locale)
1308}
1309
1310// https://learn.microsoft.com/en-us/windows/win32/api/dwrite/ne-dwrite-dwrite_font_feature_tag
1311fn apply_font_features(
1312 direct_write_features: &IDWriteTypography,
1313 features: &FontFeatures,
1314) -> Result<()> {
1315 let tag_values = features.tag_value_list();
1316 if tag_values.is_empty() {
1317 return Ok(());
1318 }
1319
1320 // All of these features are enabled by default by DirectWrite.
1321 // If you want to (and can) peek into the source of DirectWrite
1322 let mut feature_liga = make_direct_write_feature("liga", 1);
1323 let mut feature_clig = make_direct_write_feature("clig", 1);
1324 let mut feature_calt = make_direct_write_feature("calt", 1);
1325
1326 for (tag, value) in tag_values {
1327 if tag.as_str() == "liga" && *value == 0 {
1328 feature_liga.parameter = 0;
1329 continue;
1330 }
1331 if tag.as_str() == "clig" && *value == 0 {
1332 feature_clig.parameter = 0;
1333 continue;
1334 }
1335 if tag.as_str() == "calt" && *value == 0 {
1336 feature_calt.parameter = 0;
1337 continue;
1338 }
1339
1340 unsafe {
1341 direct_write_features.AddFontFeature(make_direct_write_feature(&tag, *value))?;
1342 }
1343 }
1344 unsafe {
1345 direct_write_features.AddFontFeature(feature_liga)?;
1346 direct_write_features.AddFontFeature(feature_clig)?;
1347 direct_write_features.AddFontFeature(feature_calt)?;
1348 }
1349
1350 Ok(())
1351}
1352
1353#[inline]
1354fn make_direct_write_feature(feature_name: &str, parameter: u32) -> DWRITE_FONT_FEATURE {
1355 let tag = make_direct_write_tag(feature_name);
1356 DWRITE_FONT_FEATURE {
1357 nameTag: tag,
1358 parameter,
1359 }
1360}
1361
1362#[inline]
1363fn make_open_type_tag(tag_name: &str) -> u32 {
1364 let bytes = tag_name.bytes().collect_vec();
1365 assert_eq!(bytes.len(), 4);
1366 ((bytes[3] as u32) << 24)
1367 | ((bytes[2] as u32) << 16)
1368 | ((bytes[1] as u32) << 8)
1369 | (bytes[0] as u32)
1370}
1371
1372#[inline]
1373fn make_direct_write_tag(tag_name: &str) -> DWRITE_FONT_FEATURE_TAG {
1374 DWRITE_FONT_FEATURE_TAG(make_open_type_tag(tag_name))
1375}
1376
1377#[inline]
1378fn get_name(string: IDWriteLocalizedStrings, locale: &str) -> Result<String> {
1379 let mut locale_name_index = 0u32;
1380 let mut exists = BOOL(0);
1381 unsafe {
1382 string.FindLocaleName(
1383 &HSTRING::from(locale),
1384 &mut locale_name_index,
1385 &mut exists as _,
1386 )?
1387 };
1388 if !exists.as_bool() {
1389 unsafe {
1390 string.FindLocaleName(
1391 DEFAULT_LOCALE_NAME,
1392 &mut locale_name_index as _,
1393 &mut exists as _,
1394 )?
1395 };
1396 anyhow::ensure!(exists.as_bool(), "No localised string for {locale}");
1397 }
1398
1399 let name_length = unsafe { string.GetStringLength(locale_name_index) }? as usize;
1400 let mut name_vec = vec![0u16; name_length + 1];
1401 unsafe {
1402 string.GetString(locale_name_index, &mut name_vec)?;
1403 }
1404
1405 Ok(String::from_utf16_lossy(&name_vec[..name_length]))
1406}
1407
1408#[inline]
1409fn translate_color(color: &DWRITE_COLOR_F) -> D2D1_COLOR_F {
1410 D2D1_COLOR_F {
1411 r: color.r,
1412 g: color.g,
1413 b: color.b,
1414 a: color.a,
1415 }
1416}
1417
1418fn get_system_ui_font_name() -> SharedString {
1419 unsafe {
1420 let mut info: LOGFONTW = std::mem::zeroed();
1421 let font_family = if SystemParametersInfoW(
1422 SPI_GETICONTITLELOGFONT,
1423 std::mem::size_of::<LOGFONTW>() as u32,
1424 Some(&mut info as *mut _ as _),
1425 SYSTEM_PARAMETERS_INFO_UPDATE_FLAGS(0),
1426 )
1427 .log_err()
1428 .is_none()
1429 {
1430 // https://learn.microsoft.com/en-us/windows/win32/uxguide/vis-fonts
1431 // Segoe UI is the Windows font intended for user interface text strings.
1432 "Segoe UI".into()
1433 } else {
1434 let font_name = String::from_utf16_lossy(&info.lfFaceName);
1435 font_name.trim_matches(char::from(0)).to_owned().into()
1436 };
1437 log::info!("Use {} as UI font.", font_family);
1438 font_family
1439 }
1440}
1441
1442#[inline]
1443fn get_render_target_property(
1444 pixel_format: DXGI_FORMAT,
1445 alpha_mode: D2D1_ALPHA_MODE,
1446) -> D2D1_RENDER_TARGET_PROPERTIES {
1447 D2D1_RENDER_TARGET_PROPERTIES {
1448 r#type: D2D1_RENDER_TARGET_TYPE_DEFAULT,
1449 pixelFormat: D2D1_PIXEL_FORMAT {
1450 format: pixel_format,
1451 alphaMode: alpha_mode,
1452 },
1453 dpiX: 96.0,
1454 dpiY: 96.0,
1455 usage: D2D1_RENDER_TARGET_USAGE_NONE,
1456 minLevel: D2D1_FEATURE_LEVEL_DEFAULT,
1457 }
1458}
1459
1460// One would think that with newer DirectWrite method: IDWriteFontFace4::GetGlyphImageFormats
1461// but that doesn't seem to work for some glyphs, say ❤
1462fn is_color_glyph(
1463 font_face: &IDWriteFontFace3,
1464 glyph_id: GlyphId,
1465 factory: &IDWriteFactory5,
1466) -> bool {
1467 let glyph_run = DWRITE_GLYPH_RUN {
1468 fontFace: unsafe { std::mem::transmute_copy(font_face) },
1469 fontEmSize: 14.0,
1470 glyphCount: 1,
1471 glyphIndices: &(glyph_id.0 as u16),
1472 glyphAdvances: &0.0,
1473 glyphOffsets: &DWRITE_GLYPH_OFFSET {
1474 advanceOffset: 0.0,
1475 ascenderOffset: 0.0,
1476 },
1477 isSideways: BOOL(0),
1478 bidiLevel: 0,
1479 };
1480 unsafe {
1481 factory.TranslateColorGlyphRun(
1482 Vector2::default(),
1483 &glyph_run as _,
1484 None,
1485 DWRITE_GLYPH_IMAGE_FORMATS_COLR
1486 | DWRITE_GLYPH_IMAGE_FORMATS_SVG
1487 | DWRITE_GLYPH_IMAGE_FORMATS_PNG
1488 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
1489 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8,
1490 DWRITE_MEASURING_MODE_NATURAL,
1491 None,
1492 0,
1493 )
1494 }
1495 .is_ok()
1496}
1497
1498const DEFAULT_LOCALE_NAME: PCWSTR = windows::core::w!("en-US");
1499const BRUSH_COLOR: D2D1_COLOR_F = D2D1_COLOR_F {
1500 r: 1.0,
1501 g: 1.0,
1502 b: 1.0,
1503 a: 1.0,
1504};