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 Direct3D::D3D_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP,
14 Direct3D11::*,
15 DirectWrite::*,
16 Dxgi::Common::*,
17 Gdi::{IsRectEmpty, LOGFONTW},
18 Imaging::*,
19 },
20 System::SystemServices::LOCALE_NAME_MAX_LENGTH,
21 UI::WindowsAndMessaging::*,
22 },
23 core::*,
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}
37
38pub(crate) struct DirectWriteTextSystem(RwLock<DirectWriteState>);
39
40struct DirectWriteComponent {
41 locale: String,
42 factory: IDWriteFactory5,
43 bitmap_factory: AgileReference<IWICImagingFactory>,
44 in_memory_loader: IDWriteInMemoryFontFileLoader,
45 builder: IDWriteFontSetBuilder1,
46 text_renderer: Arc<TextRendererWrapper>,
47
48 render_params: IDWriteRenderingParams3,
49 gpu_state: GPUState,
50}
51
52struct GPUState {
53 device: ID3D11Device,
54 device_context: ID3D11DeviceContext,
55 sampler: [Option<ID3D11SamplerState>; 1],
56 blend_state: ID3D11BlendState,
57 vertex_shader: ID3D11VertexShader,
58 pixel_shader: ID3D11PixelShader,
59}
60
61struct DirectWriteState {
62 components: DirectWriteComponent,
63 system_ui_font_name: SharedString,
64 system_font_collection: IDWriteFontCollection1,
65 custom_font_collection: IDWriteFontCollection1,
66 fonts: Vec<FontInfo>,
67 font_selections: HashMap<Font, FontId>,
68 font_id_by_identifier: HashMap<FontIdentifier, FontId>,
69}
70
71#[derive(Debug, Clone, Hash, PartialEq, Eq)]
72struct FontIdentifier {
73 postscript_name: String,
74 weight: i32,
75 style: i32,
76}
77
78impl DirectWriteComponent {
79 pub fn new(bitmap_factory: &IWICImagingFactory, gpu_context: &DirectXDevices) -> Result<Self> {
80 // todo: ideally this would not be a large unsafe block but smaller isolated ones for easier auditing
81 unsafe {
82 let factory: IDWriteFactory5 = DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED)?;
83 let bitmap_factory = AgileReference::new(bitmap_factory)?;
84 // The `IDWriteInMemoryFontFileLoader` here is supported starting from
85 // Windows 10 Creators Update, which consequently requires the entire
86 // `DirectWriteTextSystem` to run on `win10 1703`+.
87 let in_memory_loader = factory.CreateInMemoryFontFileLoader()?;
88 factory.RegisterFontFileLoader(&in_memory_loader)?;
89 let builder = factory.CreateFontSetBuilder()?;
90 let mut locale_vec = vec![0u16; LOCALE_NAME_MAX_LENGTH as usize];
91 GetUserDefaultLocaleName(&mut locale_vec);
92 let locale = String::from_utf16_lossy(&locale_vec);
93 let text_renderer = Arc::new(TextRendererWrapper::new(&locale));
94
95 let render_params = {
96 let default_params: IDWriteRenderingParams3 =
97 factory.CreateRenderingParams()?.cast()?;
98 let gamma = default_params.GetGamma();
99 let enhanced_contrast = default_params.GetEnhancedContrast();
100 let gray_contrast = default_params.GetGrayscaleEnhancedContrast();
101 let cleartype_level = default_params.GetClearTypeLevel();
102 let grid_fit_mode = default_params.GetGridFitMode();
103
104 factory.CreateCustomRenderingParams(
105 gamma,
106 enhanced_contrast,
107 gray_contrast,
108 cleartype_level,
109 DWRITE_PIXEL_GEOMETRY_RGB,
110 DWRITE_RENDERING_MODE1_NATURAL_SYMMETRIC,
111 grid_fit_mode,
112 )?
113 };
114
115 let gpu_state = GPUState::new(gpu_context)?;
116
117 Ok(DirectWriteComponent {
118 locale,
119 factory,
120 bitmap_factory,
121 in_memory_loader,
122 builder,
123 text_renderer,
124 render_params,
125 gpu_state,
126 })
127 }
128 }
129}
130
131impl GPUState {
132 fn new(gpu_context: &DirectXDevices) -> Result<Self> {
133 let device = gpu_context.device.clone();
134 let device_context = gpu_context.device_context.clone();
135
136 let blend_state = {
137 let mut blend_state = None;
138 let desc = D3D11_BLEND_DESC {
139 AlphaToCoverageEnable: false.into(),
140 IndependentBlendEnable: false.into(),
141 RenderTarget: [
142 D3D11_RENDER_TARGET_BLEND_DESC {
143 BlendEnable: true.into(),
144 SrcBlend: D3D11_BLEND_SRC_ALPHA,
145 DestBlend: D3D11_BLEND_INV_SRC_ALPHA,
146 BlendOp: D3D11_BLEND_OP_ADD,
147 SrcBlendAlpha: D3D11_BLEND_SRC_ALPHA,
148 DestBlendAlpha: D3D11_BLEND_INV_SRC_ALPHA,
149 BlendOpAlpha: D3D11_BLEND_OP_ADD,
150 RenderTargetWriteMask: D3D11_COLOR_WRITE_ENABLE_ALL.0 as u8,
151 },
152 Default::default(),
153 Default::default(),
154 Default::default(),
155 Default::default(),
156 Default::default(),
157 Default::default(),
158 Default::default(),
159 ],
160 };
161 unsafe { device.CreateBlendState(&desc, Some(&mut blend_state)) }?;
162 blend_state.unwrap()
163 };
164
165 let sampler = {
166 let mut sampler = None;
167 let desc = D3D11_SAMPLER_DESC {
168 Filter: D3D11_FILTER_MIN_MAG_MIP_POINT,
169 AddressU: D3D11_TEXTURE_ADDRESS_BORDER,
170 AddressV: D3D11_TEXTURE_ADDRESS_BORDER,
171 AddressW: D3D11_TEXTURE_ADDRESS_BORDER,
172 MipLODBias: 0.0,
173 MaxAnisotropy: 1,
174 ComparisonFunc: D3D11_COMPARISON_ALWAYS,
175 BorderColor: [0.0, 0.0, 0.0, 0.0],
176 MinLOD: 0.0,
177 MaxLOD: 0.0,
178 };
179 unsafe { device.CreateSamplerState(&desc, Some(&mut sampler)) }?;
180 [sampler]
181 };
182
183 let vertex_shader = {
184 let source = shader_resources::RawShaderBytes::new(
185 shader_resources::ShaderModule::EmojiRasterization,
186 shader_resources::ShaderTarget::Vertex,
187 )?;
188 let mut shader = None;
189 unsafe { device.CreateVertexShader(source.as_bytes(), None, Some(&mut shader)) }?;
190 shader.unwrap()
191 };
192
193 let pixel_shader = {
194 let source = shader_resources::RawShaderBytes::new(
195 shader_resources::ShaderModule::EmojiRasterization,
196 shader_resources::ShaderTarget::Fragment,
197 )?;
198 let mut shader = None;
199 unsafe { device.CreatePixelShader(source.as_bytes(), None, Some(&mut shader)) }?;
200 shader.unwrap()
201 };
202
203 Ok(Self {
204 device,
205 device_context,
206 sampler,
207 blend_state,
208 vertex_shader,
209 pixel_shader,
210 })
211 }
212}
213
214impl DirectWriteTextSystem {
215 pub(crate) fn new(
216 gpu_context: &DirectXDevices,
217 bitmap_factory: &IWICImagingFactory,
218 ) -> Result<Self> {
219 let components = DirectWriteComponent::new(bitmap_factory, gpu_context)?;
220 let system_font_collection = unsafe {
221 let mut result = std::mem::zeroed();
222 components
223 .factory
224 .GetSystemFontCollection(false, &mut result, true)?;
225 result.unwrap()
226 };
227 let custom_font_set = unsafe { components.builder.CreateFontSet()? };
228 let custom_font_collection = unsafe {
229 components
230 .factory
231 .CreateFontCollectionFromFontSet(&custom_font_set)?
232 };
233 let system_ui_font_name = get_system_ui_font_name();
234
235 Ok(Self(RwLock::new(DirectWriteState {
236 components,
237 system_ui_font_name,
238 system_font_collection,
239 custom_font_collection,
240 fonts: Vec::new(),
241 font_selections: HashMap::default(),
242 font_id_by_identifier: HashMap::default(),
243 })))
244 }
245}
246
247impl PlatformTextSystem for DirectWriteTextSystem {
248 fn add_fonts(&self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
249 self.0.write().add_fonts(fonts)
250 }
251
252 fn all_font_names(&self) -> Vec<String> {
253 self.0.read().all_font_names()
254 }
255
256 fn font_id(&self, font: &Font) -> Result<FontId> {
257 let lock = self.0.upgradable_read();
258 if let Some(font_id) = lock.font_selections.get(font) {
259 Ok(*font_id)
260 } else {
261 let mut lock = RwLockUpgradableReadGuard::upgrade(lock);
262 let font_id = lock.select_font(font);
263 lock.font_selections.insert(font.clone(), font_id);
264 Ok(font_id)
265 }
266 }
267
268 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
269 self.0.read().font_metrics(font_id)
270 }
271
272 fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
273 self.0.read().get_typographic_bounds(font_id, glyph_id)
274 }
275
276 fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> anyhow::Result<Size<f32>> {
277 self.0.read().get_advance(font_id, glyph_id)
278 }
279
280 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
281 self.0.read().glyph_for_char(font_id, ch)
282 }
283
284 fn glyph_raster_bounds(
285 &self,
286 params: &RenderGlyphParams,
287 ) -> anyhow::Result<Bounds<DevicePixels>> {
288 self.0.read().raster_bounds(params)
289 }
290
291 fn rasterize_glyph(
292 &self,
293 params: &RenderGlyphParams,
294 raster_bounds: Bounds<DevicePixels>,
295 ) -> anyhow::Result<(Size<DevicePixels>, Vec<u8>)> {
296 self.0.read().rasterize_glyph(params, raster_bounds)
297 }
298
299 fn layout_line(&self, text: &str, font_size: Pixels, runs: &[FontRun]) -> LineLayout {
300 self.0
301 .write()
302 .layout_line(text, font_size, runs)
303 .log_err()
304 .unwrap_or(LineLayout {
305 font_size,
306 ..Default::default()
307 })
308 }
309}
310
311impl DirectWriteState {
312 fn add_fonts(&mut self, fonts: Vec<Cow<'static, [u8]>>) -> Result<()> {
313 for font_data in fonts {
314 match font_data {
315 Cow::Borrowed(data) => unsafe {
316 let font_file = self
317 .components
318 .in_memory_loader
319 .CreateInMemoryFontFileReference(
320 &self.components.factory,
321 data.as_ptr() as _,
322 data.len() as _,
323 None,
324 )?;
325 self.components.builder.AddFontFile(&font_file)?;
326 },
327 Cow::Owned(data) => unsafe {
328 let font_file = self
329 .components
330 .in_memory_loader
331 .CreateInMemoryFontFileReference(
332 &self.components.factory,
333 data.as_ptr() as _,
334 data.len() as _,
335 None,
336 )?;
337 self.components.builder.AddFontFile(&font_file)?;
338 },
339 }
340 }
341 let set = unsafe { self.components.builder.CreateFontSet()? };
342 let collection = unsafe {
343 self.components
344 .factory
345 .CreateFontCollectionFromFontSet(&set)?
346 };
347 self.custom_font_collection = collection;
348
349 Ok(())
350 }
351
352 fn generate_font_fallbacks(
353 &self,
354 fallbacks: &FontFallbacks,
355 ) -> Result<Option<IDWriteFontFallback>> {
356 if fallbacks.fallback_list().is_empty() {
357 return Ok(None);
358 }
359 unsafe {
360 let builder = self.components.factory.CreateFontFallbackBuilder()?;
361 let font_set = &self.system_font_collection.GetFontSet()?;
362 for family_name in fallbacks.fallback_list() {
363 let Some(fonts) = font_set
364 .GetMatchingFonts(
365 &HSTRING::from(family_name),
366 DWRITE_FONT_WEIGHT_NORMAL,
367 DWRITE_FONT_STRETCH_NORMAL,
368 DWRITE_FONT_STYLE_NORMAL,
369 )
370 .log_err()
371 else {
372 continue;
373 };
374 if fonts.GetFontCount() == 0 {
375 log::error!("No matching font found for {}", family_name);
376 continue;
377 }
378 let font = fonts.GetFontFaceReference(0)?.CreateFontFace()?;
379 let mut count = 0;
380 font.GetUnicodeRanges(None, &mut count).ok();
381 if count == 0 {
382 continue;
383 }
384 let mut unicode_ranges = vec![DWRITE_UNICODE_RANGE::default(); count as usize];
385 let Some(_) = font
386 .GetUnicodeRanges(Some(&mut unicode_ranges), &mut count)
387 .log_err()
388 else {
389 continue;
390 };
391 let target_family_name = HSTRING::from(family_name);
392 builder.AddMapping(
393 &unicode_ranges,
394 &[target_family_name.as_ptr()],
395 None,
396 None,
397 None,
398 1.0,
399 )?;
400 }
401 let system_fallbacks = self.components.factory.GetSystemFontFallback()?;
402 builder.AddMappings(&system_fallbacks)?;
403 Ok(Some(builder.CreateFontFallback()?))
404 }
405 }
406
407 unsafe fn generate_font_features(
408 &self,
409 font_features: &FontFeatures,
410 ) -> Result<IDWriteTypography> {
411 let direct_write_features = unsafe { self.components.factory.CreateTypography()? };
412 apply_font_features(&direct_write_features, font_features)?;
413 Ok(direct_write_features)
414 }
415
416 unsafe fn get_font_id_from_font_collection(
417 &mut self,
418 family_name: &str,
419 font_weight: FontWeight,
420 font_style: FontStyle,
421 font_features: &FontFeatures,
422 font_fallbacks: Option<&FontFallbacks>,
423 is_system_font: bool,
424 ) -> Option<FontId> {
425 let collection = if is_system_font {
426 &self.system_font_collection
427 } else {
428 &self.custom_font_collection
429 };
430 let fontset = unsafe { collection.GetFontSet().log_err()? };
431 let font = unsafe {
432 fontset
433 .GetMatchingFonts(
434 &HSTRING::from(family_name),
435 font_weight.into(),
436 DWRITE_FONT_STRETCH_NORMAL,
437 font_style.into(),
438 )
439 .log_err()?
440 };
441 let total_number = unsafe { font.GetFontCount() };
442 for index in 0..total_number {
443 let Some(font_face_ref) = (unsafe { font.GetFontFaceReference(index).log_err() })
444 else {
445 continue;
446 };
447 let Some(font_face) = (unsafe { font_face_ref.CreateFontFace().log_err() }) else {
448 continue;
449 };
450 let Some(identifier) = get_font_identifier(&font_face, &self.components.locale) else {
451 continue;
452 };
453 let Some(direct_write_features) =
454 (unsafe { self.generate_font_features(font_features).log_err() })
455 else {
456 continue;
457 };
458 let fallbacks = font_fallbacks
459 .and_then(|fallbacks| self.generate_font_fallbacks(fallbacks).log_err().flatten());
460 let font_info = FontInfo {
461 font_family: family_name.to_owned(),
462 font_face,
463 features: direct_write_features,
464 fallbacks,
465 is_system_font,
466 };
467 let font_id = FontId(self.fonts.len());
468 self.fonts.push(font_info);
469 self.font_id_by_identifier.insert(identifier, font_id);
470 return Some(font_id);
471 }
472 None
473 }
474
475 unsafe fn update_system_font_collection(&mut self) {
476 let mut collection = unsafe { std::mem::zeroed() };
477 if unsafe {
478 self.components
479 .factory
480 .GetSystemFontCollection(false, &mut collection, true)
481 .log_err()
482 .is_some()
483 } {
484 self.system_font_collection = collection.unwrap();
485 }
486 }
487
488 fn select_font(&mut self, target_font: &Font) -> FontId {
489 unsafe {
490 if target_font.family == ".SystemUIFont" {
491 let family = self.system_ui_font_name.clone();
492 self.find_font_id(
493 family.as_ref(),
494 target_font.weight,
495 target_font.style,
496 &target_font.features,
497 target_font.fallbacks.as_ref(),
498 )
499 .unwrap()
500 } else {
501 self.find_font_id(
502 target_font.family.as_ref(),
503 target_font.weight,
504 target_font.style,
505 &target_font.features,
506 target_font.fallbacks.as_ref(),
507 )
508 .unwrap_or_else(|| {
509 #[cfg(any(test, feature = "test-support"))]
510 {
511 panic!("ERROR: {} font not found!", target_font.family);
512 }
513 #[cfg(not(any(test, feature = "test-support")))]
514 {
515 let family = self.system_ui_font_name.clone();
516 log::error!("{} not found, use {} instead.", target_font.family, family);
517 self.get_font_id_from_font_collection(
518 family.as_ref(),
519 target_font.weight,
520 target_font.style,
521 &target_font.features,
522 target_font.fallbacks.as_ref(),
523 true,
524 )
525 .unwrap()
526 }
527 })
528 }
529 }
530 }
531
532 unsafe fn find_font_id(
533 &mut self,
534 family_name: &str,
535 weight: FontWeight,
536 style: FontStyle,
537 features: &FontFeatures,
538 fallbacks: Option<&FontFallbacks>,
539 ) -> Option<FontId> {
540 // try to find target font in custom font collection first
541 unsafe {
542 self.get_font_id_from_font_collection(
543 family_name,
544 weight,
545 style,
546 features,
547 fallbacks,
548 false,
549 )
550 .or_else(|| {
551 self.get_font_id_from_font_collection(
552 family_name,
553 weight,
554 style,
555 features,
556 fallbacks,
557 true,
558 )
559 })
560 .or_else(|| {
561 self.update_system_font_collection();
562 self.get_font_id_from_font_collection(
563 family_name,
564 weight,
565 style,
566 features,
567 fallbacks,
568 true,
569 )
570 })
571 }
572 }
573
574 fn layout_line(
575 &mut self,
576 text: &str,
577 font_size: Pixels,
578 font_runs: &[FontRun],
579 ) -> Result<LineLayout> {
580 if font_runs.is_empty() {
581 return Ok(LineLayout {
582 font_size,
583 ..Default::default()
584 });
585 }
586 unsafe {
587 let text_renderer = self.components.text_renderer.clone();
588 let text_wide = text.encode_utf16().collect_vec();
589
590 let mut utf8_offset = 0usize;
591 let mut utf16_offset = 0u32;
592 let text_layout = {
593 let first_run = &font_runs[0];
594 let font_info = &self.fonts[first_run.font_id.0];
595 let collection = if font_info.is_system_font {
596 &self.system_font_collection
597 } else {
598 &self.custom_font_collection
599 };
600 let format: IDWriteTextFormat1 = self
601 .components
602 .factory
603 .CreateTextFormat(
604 &HSTRING::from(&font_info.font_family),
605 collection,
606 font_info.font_face.GetWeight(),
607 font_info.font_face.GetStyle(),
608 DWRITE_FONT_STRETCH_NORMAL,
609 font_size.0,
610 &HSTRING::from(&self.components.locale),
611 )?
612 .cast()?;
613 if let Some(ref fallbacks) = font_info.fallbacks {
614 format.SetFontFallback(fallbacks)?;
615 }
616
617 let layout = self.components.factory.CreateTextLayout(
618 &text_wide,
619 &format,
620 f32::INFINITY,
621 f32::INFINITY,
622 )?;
623 let current_text = &text[utf8_offset..(utf8_offset + first_run.len)];
624 utf8_offset += first_run.len;
625 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
626 let text_range = DWRITE_TEXT_RANGE {
627 startPosition: utf16_offset,
628 length: current_text_utf16_length,
629 };
630 layout.SetTypography(&font_info.features, text_range)?;
631 utf16_offset += current_text_utf16_length;
632
633 layout
634 };
635
636 let mut first_run = true;
637 let mut ascent = Pixels::default();
638 let mut descent = Pixels::default();
639 for run in font_runs {
640 if first_run {
641 first_run = false;
642 let mut metrics = vec![DWRITE_LINE_METRICS::default(); 4];
643 let mut line_count = 0u32;
644 text_layout.GetLineMetrics(Some(&mut metrics), &mut line_count as _)?;
645 ascent = px(metrics[0].baseline);
646 descent = px(metrics[0].height - metrics[0].baseline);
647 continue;
648 }
649 let font_info = &self.fonts[run.font_id.0];
650 let current_text = &text[utf8_offset..(utf8_offset + run.len)];
651 utf8_offset += run.len;
652 let current_text_utf16_length = current_text.encode_utf16().count() as u32;
653
654 let collection = if font_info.is_system_font {
655 &self.system_font_collection
656 } else {
657 &self.custom_font_collection
658 };
659 let text_range = DWRITE_TEXT_RANGE {
660 startPosition: utf16_offset,
661 length: current_text_utf16_length,
662 };
663 utf16_offset += current_text_utf16_length;
664 text_layout.SetFontCollection(collection, text_range)?;
665 text_layout
666 .SetFontFamilyName(&HSTRING::from(&font_info.font_family), text_range)?;
667 text_layout.SetFontSize(font_size.0, text_range)?;
668 text_layout.SetFontStyle(font_info.font_face.GetStyle(), text_range)?;
669 text_layout.SetFontWeight(font_info.font_face.GetWeight(), text_range)?;
670 text_layout.SetTypography(&font_info.features, text_range)?;
671 }
672
673 let mut runs = Vec::new();
674 let renderer_context = RendererContext {
675 text_system: self,
676 index_converter: StringIndexConverter::new(text),
677 runs: &mut runs,
678 width: 0.0,
679 };
680 text_layout.Draw(
681 Some(&renderer_context as *const _ as _),
682 &text_renderer.0,
683 0.0,
684 0.0,
685 )?;
686 let width = px(renderer_context.width);
687
688 Ok(LineLayout {
689 font_size,
690 width,
691 ascent,
692 descent,
693 runs,
694 len: text.len(),
695 })
696 }
697 }
698
699 fn font_metrics(&self, font_id: FontId) -> FontMetrics {
700 unsafe {
701 let font_info = &self.fonts[font_id.0];
702 let mut metrics = std::mem::zeroed();
703 font_info.font_face.GetMetrics(&mut metrics);
704
705 FontMetrics {
706 units_per_em: metrics.Base.designUnitsPerEm as _,
707 ascent: metrics.Base.ascent as _,
708 descent: -(metrics.Base.descent as f32),
709 line_gap: metrics.Base.lineGap as _,
710 underline_position: metrics.Base.underlinePosition as _,
711 underline_thickness: metrics.Base.underlineThickness as _,
712 cap_height: metrics.Base.capHeight as _,
713 x_height: metrics.Base.xHeight as _,
714 bounding_box: Bounds {
715 origin: Point {
716 x: metrics.glyphBoxLeft as _,
717 y: metrics.glyphBoxBottom as _,
718 },
719 size: Size {
720 width: (metrics.glyphBoxRight - metrics.glyphBoxLeft) as _,
721 height: (metrics.glyphBoxTop - metrics.glyphBoxBottom) as _,
722 },
723 },
724 }
725 }
726 }
727
728 fn create_glyph_run_analysis(
729 &self,
730 params: &RenderGlyphParams,
731 ) -> Result<IDWriteGlyphRunAnalysis> {
732 let font = &self.fonts[params.font_id.0];
733 let glyph_id = [params.glyph_id.0 as u16];
734 let advance = [0.0];
735 let offset = [DWRITE_GLYPH_OFFSET::default()];
736 let glyph_run = DWRITE_GLYPH_RUN {
737 fontFace: unsafe { std::mem::transmute_copy(&font.font_face) },
738 fontEmSize: params.font_size.0,
739 glyphCount: 1,
740 glyphIndices: glyph_id.as_ptr(),
741 glyphAdvances: advance.as_ptr(),
742 glyphOffsets: offset.as_ptr(),
743 isSideways: BOOL(0),
744 bidiLevel: 0,
745 };
746 let transform = DWRITE_MATRIX {
747 m11: params.scale_factor,
748 m12: 0.0,
749 m21: 0.0,
750 m22: params.scale_factor,
751 dx: 0.0,
752 dy: 0.0,
753 };
754 let subpixel_shift = params
755 .subpixel_variant
756 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
757 let baseline_origin_x = subpixel_shift.x / params.scale_factor;
758 let baseline_origin_y = subpixel_shift.y / params.scale_factor;
759
760 let mut rendering_mode = DWRITE_RENDERING_MODE1::default();
761 let mut grid_fit_mode = DWRITE_GRID_FIT_MODE::default();
762 unsafe {
763 font.font_face.GetRecommendedRenderingMode(
764 params.font_size.0,
765 // The dpi here seems that it has the same effect with `Some(&transform)`
766 1.0,
767 1.0,
768 Some(&transform),
769 false,
770 DWRITE_OUTLINE_THRESHOLD_ANTIALIASED,
771 DWRITE_MEASURING_MODE_NATURAL,
772 &self.components.render_params,
773 &mut rendering_mode,
774 &mut grid_fit_mode,
775 )?;
776 }
777
778 let antialias_mode = if params.is_emoji {
779 DWRITE_TEXT_ANTIALIAS_MODE_CLEARTYPE
780 } else {
781 DWRITE_TEXT_ANTIALIAS_MODE_CLEARTYPE
782 };
783
784 let glyph_analysis = unsafe {
785 self.components.factory.CreateGlyphRunAnalysis(
786 &glyph_run,
787 Some(&transform),
788 rendering_mode,
789 DWRITE_MEASURING_MODE_NATURAL,
790 grid_fit_mode,
791 antialias_mode,
792 baseline_origin_x,
793 baseline_origin_y,
794 )
795 }?;
796 Ok(glyph_analysis)
797 }
798
799 fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
800 let glyph_analysis = self.create_glyph_run_analysis(params)?;
801
802 if params.is_emoji {
803 let bounds =
804 unsafe { glyph_analysis.GetAlphaTextureBounds(DWRITE_TEXTURE_CLEARTYPE_3x1)? };
805 // If it's empty, retry with grayscale AA.
806 if !unsafe { IsRectEmpty(&bounds) }.as_bool() {
807 return Ok(Bounds {
808 origin: point((bounds.left as i32).into(), (bounds.top as i32).into()),
809 size: size(
810 (bounds.right - bounds.left).into(),
811 (bounds.bottom - bounds.top).into(),
812 ),
813 });
814 }
815 }
816
817 let bounds = unsafe { glyph_analysis.GetAlphaTextureBounds(DWRITE_TEXTURE_CLEARTYPE_3x1)? };
818
819 if bounds.right < bounds.left {
820 Ok(Bounds {
821 origin: point(0.into(), 0.into()),
822 size: size(0.into(), 0.into()),
823 })
824 } else {
825 Ok(Bounds {
826 origin: point((bounds.left as i32).into(), (bounds.top as i32).into()),
827 size: size(
828 (bounds.right - bounds.left).into(),
829 (bounds.bottom - bounds.top).into(),
830 ),
831 })
832 }
833 }
834
835 fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
836 let font_info = &self.fonts[font_id.0];
837 let codepoints = [ch as u32];
838 let mut glyph_indices = vec![0u16; 1];
839 unsafe {
840 font_info
841 .font_face
842 .GetGlyphIndices(codepoints.as_ptr(), 1, glyph_indices.as_mut_ptr())
843 .log_err()
844 }
845 .map(|_| GlyphId(glyph_indices[0] as u32))
846 }
847
848 fn rasterize_glyph(
849 &self,
850 params: &RenderGlyphParams,
851 glyph_bounds: Bounds<DevicePixels>,
852 ) -> Result<(Size<DevicePixels>, Vec<u8>)> {
853 if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 {
854 anyhow::bail!("glyph bounds are empty");
855 }
856
857 let bitmap_size = glyph_bounds.size;
858
859 let mut bitmap_data: Vec<u8>;
860 if params.is_emoji {
861 let glyph_analysis = self.create_glyph_run_analysis(params)?;
862
863 if let Ok(color) = self.rasterize_color(¶ms, glyph_bounds) {
864 bitmap_data = color;
865 } else {
866 let monochrome = self.rasterize_monochrome(&glyph_analysis, glyph_bounds)?;
867 bitmap_data = monochrome
868 .into_iter()
869 .flat_map(|pixel| [0, 0, 0, pixel])
870 .collect::<Vec<_>>();
871 }
872 } else {
873 let glyph_analysis = self.create_glyph_run_analysis(params)?;
874 bitmap_data = self.rasterize_monochrome(&glyph_analysis, glyph_bounds)?;
875 }
876
877 Ok((bitmap_size, bitmap_data))
878 }
879
880 fn rasterize_monochrome(
881 &self,
882 glyph_analysis: &IDWriteGlyphRunAnalysis,
883 glyph_bounds: Bounds<DevicePixels>,
884 ) -> Result<Vec<u8>> {
885 let multisampled_bounds =
886 unsafe { glyph_analysis.GetAlphaTextureBounds(DWRITE_TEXTURE_CLEARTYPE_3x1)? };
887 let multisampled_size = size(
888 multisampled_bounds.right - multisampled_bounds.left,
889 multisampled_bounds.bottom - multisampled_bounds.top,
890 );
891
892 let mut bitmap_data =
893 vec![0u8; multisampled_size.width as usize * multisampled_size.height as usize * 3];
894
895 unsafe {
896 glyph_analysis.CreateAlphaTexture(
897 DWRITE_TEXTURE_CLEARTYPE_3x1,
898 &multisampled_bounds,
899 &mut bitmap_data,
900 )?;
901 }
902
903 let bitmap_factory = self.components.bitmap_factory.resolve()?;
904 let bitmap = unsafe {
905 bitmap_factory.CreateBitmapFromMemory(
906 multisampled_size.width as u32,
907 multisampled_size.height as u32,
908 &GUID_WICPixelFormat24bppRGB,
909 multisampled_size.width as u32 * 3,
910 &bitmap_data,
911 )
912 }?;
913
914 let grayscale_bitmap =
915 unsafe { WICConvertBitmapSource(&GUID_WICPixelFormat8bppGray, &bitmap) }?;
916
917 let scaler = unsafe { bitmap_factory.CreateBitmapScaler() }?;
918 unsafe {
919 scaler.Initialize(
920 &grayscale_bitmap,
921 glyph_bounds.size.width.0 as u32,
922 glyph_bounds.size.height.0 as u32,
923 WICBitmapInterpolationModeHighQualityCubic,
924 )
925 }?;
926
927 let mut bitmap_data =
928 vec![0u8; glyph_bounds.size.width.0 as usize * glyph_bounds.size.height.0 as usize];
929 unsafe {
930 scaler.CopyPixels(
931 std::ptr::null() as _,
932 glyph_bounds.size.width.0 as u32,
933 &mut bitmap_data,
934 )
935 }?;
936
937 Ok(bitmap_data)
938 }
939
940 fn rasterize_color(
941 &self,
942 params: &RenderGlyphParams,
943 glyph_bounds: Bounds<DevicePixels>,
944 ) -> Result<Vec<u8>> {
945 let bitmap_size = glyph_bounds.size;
946 let subpixel_shift = params
947 .subpixel_variant
948 .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32);
949 let baseline_origin_x = subpixel_shift.x / params.scale_factor;
950 let baseline_origin_y = subpixel_shift.y / params.scale_factor;
951
952 let transform = DWRITE_MATRIX {
953 m11: params.scale_factor,
954 m12: 0.0,
955 m21: 0.0,
956 m22: params.scale_factor,
957 dx: 0.0,
958 dy: 0.0,
959 };
960
961 let font = &self.fonts[params.font_id.0];
962 let glyph_id = [params.glyph_id.0 as u16];
963 let advance = [glyph_bounds.size.width.0 as f32];
964 let offset = [DWRITE_GLYPH_OFFSET {
965 advanceOffset: -glyph_bounds.origin.x.0 as f32 / params.scale_factor,
966 ascenderOffset: glyph_bounds.origin.y.0 as f32 / params.scale_factor,
967 }];
968 let glyph_run = DWRITE_GLYPH_RUN {
969 fontFace: unsafe { std::mem::transmute_copy(&font.font_face) },
970 fontEmSize: params.font_size.0,
971 glyphCount: 1,
972 glyphIndices: glyph_id.as_ptr(),
973 glyphAdvances: advance.as_ptr(),
974 glyphOffsets: offset.as_ptr(),
975 isSideways: BOOL(0),
976 bidiLevel: 0,
977 };
978
979 // todo: support formats other than COLR
980 let color_enumerator = unsafe {
981 self.components.factory.TranslateColorGlyphRun(
982 Vector2::new(baseline_origin_x, baseline_origin_y),
983 &glyph_run,
984 None,
985 DWRITE_GLYPH_IMAGE_FORMATS_COLR,
986 DWRITE_MEASURING_MODE_NATURAL,
987 Some(&transform),
988 0,
989 )
990 }?;
991
992 let mut glyph_layers = Vec::new();
993 loop {
994 let color_run = unsafe { color_enumerator.GetCurrentRun() }?;
995 let color_run = unsafe { &*color_run };
996 let image_format = color_run.glyphImageFormat & !DWRITE_GLYPH_IMAGE_FORMATS_TRUETYPE;
997 if image_format == DWRITE_GLYPH_IMAGE_FORMATS_COLR {
998 let color_analysis = unsafe {
999 self.components.factory.CreateGlyphRunAnalysis(
1000 &color_run.Base.glyphRun as *const _,
1001 Some(&transform),
1002 DWRITE_RENDERING_MODE1_NATURAL_SYMMETRIC,
1003 DWRITE_MEASURING_MODE_NATURAL,
1004 DWRITE_GRID_FIT_MODE_DEFAULT,
1005 DWRITE_TEXT_ANTIALIAS_MODE_CLEARTYPE,
1006 baseline_origin_x,
1007 baseline_origin_y,
1008 )
1009 }?;
1010
1011 let color_bounds =
1012 unsafe { color_analysis.GetAlphaTextureBounds(DWRITE_TEXTURE_CLEARTYPE_3x1) }?;
1013
1014 let color_size = size(
1015 color_bounds.right - color_bounds.left,
1016 color_bounds.bottom - color_bounds.top,
1017 );
1018 if color_size.width > 0 && color_size.height > 0 {
1019 let mut alpha_data =
1020 vec![0u8; (color_size.width * color_size.height * 3) as usize];
1021 unsafe {
1022 color_analysis.CreateAlphaTexture(
1023 DWRITE_TEXTURE_CLEARTYPE_3x1,
1024 &color_bounds,
1025 &mut alpha_data,
1026 )
1027 }?;
1028
1029 let run_color = {
1030 let run_color = color_run.Base.runColor;
1031 Rgba {
1032 r: run_color.r,
1033 g: run_color.g,
1034 b: run_color.b,
1035 a: run_color.a,
1036 }
1037 };
1038 let bounds = bounds(point(color_bounds.left, color_bounds.top), color_size);
1039 let alpha_data = alpha_data
1040 .chunks_exact(3)
1041 .flat_map(|chunk| [chunk[0], chunk[1], chunk[2], 255])
1042 .collect::<Vec<_>>();
1043 glyph_layers.push(GlyphLayerTexture::new(
1044 &self.components.gpu_state,
1045 run_color,
1046 bounds,
1047 &alpha_data,
1048 )?);
1049 }
1050 }
1051
1052 let has_next = unsafe { color_enumerator.MoveNext() }
1053 .map(|e| e.as_bool())
1054 .unwrap_or(false);
1055 if !has_next {
1056 break;
1057 }
1058 }
1059
1060 let gpu_state = &self.components.gpu_state;
1061 let params_buffer = {
1062 let desc = D3D11_BUFFER_DESC {
1063 ByteWidth: std::mem::size_of::<GlyphLayerTextureParams>() as u32,
1064 Usage: D3D11_USAGE_DYNAMIC,
1065 BindFlags: D3D11_BIND_CONSTANT_BUFFER.0 as u32,
1066 CPUAccessFlags: D3D11_CPU_ACCESS_WRITE.0 as u32,
1067 MiscFlags: 0,
1068 StructureByteStride: 0,
1069 };
1070
1071 let mut buffer = None;
1072 unsafe {
1073 gpu_state
1074 .device
1075 .CreateBuffer(&desc, None, Some(&mut buffer))
1076 }?;
1077 [buffer]
1078 };
1079
1080 let render_target_texture = {
1081 let mut texture = None;
1082 let desc = D3D11_TEXTURE2D_DESC {
1083 Width: bitmap_size.width.0 as u32,
1084 Height: bitmap_size.height.0 as u32,
1085 MipLevels: 1,
1086 ArraySize: 1,
1087 Format: DXGI_FORMAT_B8G8R8A8_UNORM,
1088 SampleDesc: DXGI_SAMPLE_DESC {
1089 Count: 1,
1090 Quality: 0,
1091 },
1092 Usage: D3D11_USAGE_DEFAULT,
1093 BindFlags: D3D11_BIND_RENDER_TARGET.0 as u32,
1094 CPUAccessFlags: 0,
1095 MiscFlags: 0,
1096 };
1097 unsafe {
1098 gpu_state
1099 .device
1100 .CreateTexture2D(&desc, None, Some(&mut texture))
1101 }?;
1102 texture.unwrap()
1103 };
1104
1105 let render_target_view = {
1106 let desc = D3D11_RENDER_TARGET_VIEW_DESC {
1107 Format: DXGI_FORMAT_B8G8R8A8_UNORM,
1108 ViewDimension: D3D11_RTV_DIMENSION_TEXTURE2D,
1109 Anonymous: D3D11_RENDER_TARGET_VIEW_DESC_0 {
1110 Texture2D: D3D11_TEX2D_RTV { MipSlice: 0 },
1111 },
1112 };
1113 let mut rtv = None;
1114 unsafe {
1115 gpu_state.device.CreateRenderTargetView(
1116 &render_target_texture,
1117 Some(&desc),
1118 Some(&mut rtv),
1119 )
1120 }?;
1121 [rtv]
1122 };
1123
1124 let staging_texture = {
1125 let mut texture = None;
1126 let desc = D3D11_TEXTURE2D_DESC {
1127 Width: bitmap_size.width.0 as u32,
1128 Height: bitmap_size.height.0 as u32,
1129 MipLevels: 1,
1130 ArraySize: 1,
1131 Format: DXGI_FORMAT_B8G8R8A8_UNORM,
1132 SampleDesc: DXGI_SAMPLE_DESC {
1133 Count: 1,
1134 Quality: 0,
1135 },
1136 Usage: D3D11_USAGE_STAGING,
1137 BindFlags: 0,
1138 CPUAccessFlags: D3D11_CPU_ACCESS_READ.0 as u32,
1139 MiscFlags: 0,
1140 };
1141 unsafe {
1142 gpu_state
1143 .device
1144 .CreateTexture2D(&desc, None, Some(&mut texture))
1145 }?;
1146 texture.unwrap()
1147 };
1148
1149 let device_context = &gpu_state.device_context;
1150 unsafe { device_context.IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLESTRIP) };
1151 unsafe { device_context.VSSetShader(&gpu_state.vertex_shader, None) };
1152 unsafe { device_context.PSSetShader(&gpu_state.pixel_shader, None) };
1153 unsafe { device_context.VSSetConstantBuffers(0, Some(¶ms_buffer)) };
1154 unsafe { device_context.PSSetConstantBuffers(0, Some(¶ms_buffer)) };
1155 unsafe { device_context.OMSetRenderTargets(Some(&render_target_view), None) };
1156 unsafe { device_context.PSSetSamplers(0, Some(&gpu_state.sampler)) };
1157 unsafe { device_context.OMSetBlendState(&gpu_state.blend_state, None, 0xffffffff) };
1158
1159 for layer in glyph_layers {
1160 let params = GlyphLayerTextureParams {
1161 run_color: layer.run_color,
1162 bounds: layer.bounds,
1163 };
1164 unsafe {
1165 let mut dest = std::mem::zeroed();
1166 gpu_state.device_context.Map(
1167 params_buffer[0].as_ref().unwrap(),
1168 0,
1169 D3D11_MAP_WRITE_DISCARD,
1170 0,
1171 Some(&mut dest),
1172 )?;
1173 std::ptr::copy_nonoverlapping(¶ms as *const _, dest.pData as *mut _, 1);
1174 gpu_state
1175 .device_context
1176 .Unmap(params_buffer[0].as_ref().unwrap(), 0);
1177 };
1178
1179 let texture = [Some(layer.texture_view)];
1180 unsafe { device_context.PSSetShaderResources(0, Some(&texture)) };
1181
1182 let viewport = [D3D11_VIEWPORT {
1183 TopLeftX: layer.bounds.origin.x as f32,
1184 TopLeftY: layer.bounds.origin.y as f32,
1185 Width: layer.bounds.size.width as f32,
1186 Height: layer.bounds.size.height as f32,
1187 MinDepth: 0.0,
1188 MaxDepth: 1.0,
1189 }];
1190 unsafe { device_context.RSSetViewports(Some(&viewport)) };
1191
1192 unsafe { device_context.Draw(4, 0) };
1193 }
1194
1195 unsafe { device_context.CopyResource(&staging_texture, &render_target_texture) };
1196
1197 let mapped_data = {
1198 let mut mapped_data = D3D11_MAPPED_SUBRESOURCE::default();
1199 unsafe {
1200 device_context.Map(
1201 &staging_texture,
1202 0,
1203 D3D11_MAP_READ,
1204 0,
1205 Some(&mut mapped_data),
1206 )
1207 }?;
1208 mapped_data
1209 };
1210 let mut rasterized =
1211 vec![0u8; (bitmap_size.width.0 as u32 * bitmap_size.height.0 as u32 * 4) as usize];
1212
1213 for y in 0..bitmap_size.height.0 as usize {
1214 let width = bitmap_size.width.0 as usize;
1215 unsafe {
1216 std::ptr::copy_nonoverlapping::<u8>(
1217 (mapped_data.pData as *const u8).byte_add(mapped_data.RowPitch as usize * y),
1218 rasterized
1219 .as_mut_ptr()
1220 .byte_add(width * y * std::mem::size_of::<u32>()),
1221 width * std::mem::size_of::<u32>(),
1222 )
1223 };
1224 }
1225
1226 Ok(rasterized)
1227 }
1228
1229 fn get_typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
1230 unsafe {
1231 let font = &self.fonts[font_id.0].font_face;
1232 let glyph_indices = [glyph_id.0 as u16];
1233 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
1234 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
1235
1236 let metrics = &metrics[0];
1237 let advance_width = metrics.advanceWidth as i32;
1238 let advance_height = metrics.advanceHeight as i32;
1239 let left_side_bearing = metrics.leftSideBearing;
1240 let right_side_bearing = metrics.rightSideBearing;
1241 let top_side_bearing = metrics.topSideBearing;
1242 let bottom_side_bearing = metrics.bottomSideBearing;
1243 let vertical_origin_y = metrics.verticalOriginY;
1244
1245 let y_offset = vertical_origin_y + bottom_side_bearing - advance_height;
1246 let width = advance_width - (left_side_bearing + right_side_bearing);
1247 let height = advance_height - (top_side_bearing + bottom_side_bearing);
1248
1249 Ok(Bounds {
1250 origin: Point {
1251 x: left_side_bearing as f32,
1252 y: y_offset as f32,
1253 },
1254 size: Size {
1255 width: width as f32,
1256 height: height as f32,
1257 },
1258 })
1259 }
1260 }
1261
1262 fn get_advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
1263 unsafe {
1264 let font = &self.fonts[font_id.0].font_face;
1265 let glyph_indices = [glyph_id.0 as u16];
1266 let mut metrics = [DWRITE_GLYPH_METRICS::default()];
1267 font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?;
1268
1269 let metrics = &metrics[0];
1270
1271 Ok(Size {
1272 width: metrics.advanceWidth as f32,
1273 height: 0.0,
1274 })
1275 }
1276 }
1277
1278 fn all_font_names(&self) -> Vec<String> {
1279 let mut result =
1280 get_font_names_from_collection(&self.system_font_collection, &self.components.locale);
1281 result.extend(get_font_names_from_collection(
1282 &self.custom_font_collection,
1283 &self.components.locale,
1284 ));
1285 result
1286 }
1287}
1288
1289impl Drop for DirectWriteState {
1290 fn drop(&mut self) {
1291 unsafe {
1292 let _ = self
1293 .components
1294 .factory
1295 .UnregisterFontFileLoader(&self.components.in_memory_loader);
1296 }
1297 }
1298}
1299
1300struct GlyphLayerTexture {
1301 run_color: Rgba,
1302 bounds: Bounds<i32>,
1303 texture: ID3D11Texture2D,
1304 texture_view: ID3D11ShaderResourceView,
1305}
1306
1307impl GlyphLayerTexture {
1308 pub fn new(
1309 gpu_state: &GPUState,
1310 run_color: Rgba,
1311 bounds: Bounds<i32>,
1312 alpha_data: &[u8],
1313 ) -> Result<Self> {
1314 let texture_size = bounds.size;
1315
1316 let desc = D3D11_TEXTURE2D_DESC {
1317 Width: texture_size.width as u32,
1318 Height: texture_size.height as u32,
1319 MipLevels: 1,
1320 ArraySize: 1,
1321 Format: DXGI_FORMAT_R8G8B8A8_UNORM,
1322 SampleDesc: DXGI_SAMPLE_DESC {
1323 Count: 1,
1324 Quality: 0,
1325 },
1326 Usage: D3D11_USAGE_DEFAULT,
1327 BindFlags: D3D11_BIND_SHADER_RESOURCE.0 as u32,
1328 CPUAccessFlags: D3D11_CPU_ACCESS_WRITE.0 as u32,
1329 MiscFlags: 0,
1330 };
1331
1332 let texture = {
1333 let mut texture: Option<ID3D11Texture2D> = None;
1334 unsafe {
1335 gpu_state
1336 .device
1337 .CreateTexture2D(&desc, None, Some(&mut texture))?
1338 };
1339 texture.unwrap()
1340 };
1341 let texture_view = {
1342 let mut view: Option<ID3D11ShaderResourceView> = None;
1343 unsafe {
1344 gpu_state
1345 .device
1346 .CreateShaderResourceView(&texture, None, Some(&mut view))?
1347 };
1348 view.unwrap()
1349 };
1350
1351 unsafe {
1352 gpu_state.device_context.UpdateSubresource(
1353 &texture,
1354 0,
1355 None,
1356 alpha_data.as_ptr() as _,
1357 (texture_size.width * 4) as u32,
1358 0,
1359 )
1360 };
1361
1362 Ok(GlyphLayerTexture {
1363 run_color,
1364 bounds,
1365 texture,
1366 texture_view,
1367 })
1368 }
1369}
1370
1371#[repr(C)]
1372struct GlyphLayerTextureParams {
1373 bounds: Bounds<i32>,
1374 run_color: Rgba,
1375}
1376
1377struct TextRendererWrapper(pub IDWriteTextRenderer);
1378
1379impl TextRendererWrapper {
1380 pub fn new(locale_str: &str) -> Self {
1381 let inner = TextRenderer::new(locale_str);
1382 TextRendererWrapper(inner.into())
1383 }
1384}
1385
1386#[implement(IDWriteTextRenderer)]
1387struct TextRenderer {
1388 locale: String,
1389}
1390
1391impl TextRenderer {
1392 pub fn new(locale_str: &str) -> Self {
1393 TextRenderer {
1394 locale: locale_str.to_owned(),
1395 }
1396 }
1397}
1398
1399struct RendererContext<'t, 'a, 'b> {
1400 text_system: &'t mut DirectWriteState,
1401 index_converter: StringIndexConverter<'a>,
1402 runs: &'b mut Vec<ShapedRun>,
1403 width: f32,
1404}
1405
1406#[derive(Debug)]
1407struct ClusterAnalyzer<'t> {
1408 utf16_idx: usize,
1409 glyph_idx: usize,
1410 glyph_count: usize,
1411 cluster_map: &'t [u16],
1412}
1413
1414impl<'t> ClusterAnalyzer<'t> {
1415 pub fn new(cluster_map: &'t [u16], glyph_count: usize) -> Self {
1416 ClusterAnalyzer {
1417 utf16_idx: 0,
1418 glyph_idx: 0,
1419 glyph_count,
1420 cluster_map,
1421 }
1422 }
1423}
1424
1425impl Iterator for ClusterAnalyzer<'_> {
1426 type Item = (usize, usize);
1427
1428 fn next(&mut self) -> Option<(usize, usize)> {
1429 if self.utf16_idx >= self.cluster_map.len() {
1430 return None; // No more clusters
1431 }
1432 let start_utf16_idx = self.utf16_idx;
1433 let current_glyph = self.cluster_map[start_utf16_idx] as usize;
1434
1435 // Find the end of current cluster (where glyph index changes)
1436 let mut end_utf16_idx = start_utf16_idx + 1;
1437 while end_utf16_idx < self.cluster_map.len()
1438 && self.cluster_map[end_utf16_idx] as usize == current_glyph
1439 {
1440 end_utf16_idx += 1;
1441 }
1442
1443 let utf16_len = end_utf16_idx - start_utf16_idx;
1444
1445 // Calculate glyph count for this cluster
1446 let next_glyph = if end_utf16_idx < self.cluster_map.len() {
1447 self.cluster_map[end_utf16_idx] as usize
1448 } else {
1449 self.glyph_count
1450 };
1451
1452 let glyph_count = next_glyph - current_glyph;
1453
1454 // Update state for next call
1455 self.utf16_idx = end_utf16_idx;
1456 self.glyph_idx = next_glyph;
1457
1458 Some((utf16_len, glyph_count))
1459 }
1460}
1461
1462#[allow(non_snake_case)]
1463impl IDWritePixelSnapping_Impl for TextRenderer_Impl {
1464 fn IsPixelSnappingDisabled(
1465 &self,
1466 _clientdrawingcontext: *const ::core::ffi::c_void,
1467 ) -> windows::core::Result<BOOL> {
1468 Ok(BOOL(0))
1469 }
1470
1471 fn GetCurrentTransform(
1472 &self,
1473 _clientdrawingcontext: *const ::core::ffi::c_void,
1474 transform: *mut DWRITE_MATRIX,
1475 ) -> windows::core::Result<()> {
1476 unsafe {
1477 *transform = DWRITE_MATRIX {
1478 m11: 1.0,
1479 m12: 0.0,
1480 m21: 0.0,
1481 m22: 1.0,
1482 dx: 0.0,
1483 dy: 0.0,
1484 };
1485 }
1486 Ok(())
1487 }
1488
1489 fn GetPixelsPerDip(
1490 &self,
1491 _clientdrawingcontext: *const ::core::ffi::c_void,
1492 ) -> windows::core::Result<f32> {
1493 Ok(1.0)
1494 }
1495}
1496
1497#[allow(non_snake_case)]
1498impl IDWriteTextRenderer_Impl for TextRenderer_Impl {
1499 fn DrawGlyphRun(
1500 &self,
1501 clientdrawingcontext: *const ::core::ffi::c_void,
1502 _baselineoriginx: f32,
1503 _baselineoriginy: f32,
1504 _measuringmode: DWRITE_MEASURING_MODE,
1505 glyphrun: *const DWRITE_GLYPH_RUN,
1506 glyphrundescription: *const DWRITE_GLYPH_RUN_DESCRIPTION,
1507 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1508 ) -> windows::core::Result<()> {
1509 let glyphrun = unsafe { &*glyphrun };
1510 let glyph_count = glyphrun.glyphCount as usize;
1511 if glyph_count == 0 || glyphrun.fontFace.is_none() {
1512 return Ok(());
1513 }
1514 let desc = unsafe { &*glyphrundescription };
1515 let context = unsafe {
1516 &mut *(clientdrawingcontext as *const RendererContext as *mut RendererContext)
1517 };
1518 let font_face = glyphrun.fontFace.as_ref().unwrap();
1519 // This `cast()` action here should never fail since we are running on Win10+, and
1520 // `IDWriteFontFace3` requires Win10
1521 let font_face = &font_face.cast::<IDWriteFontFace3>().unwrap();
1522 let Some((font_identifier, font_struct, color_font)) =
1523 get_font_identifier_and_font_struct(font_face, &self.locale)
1524 else {
1525 return Ok(());
1526 };
1527
1528 let font_id = if let Some(id) = context
1529 .text_system
1530 .font_id_by_identifier
1531 .get(&font_identifier)
1532 {
1533 *id
1534 } else {
1535 context.text_system.select_font(&font_struct)
1536 };
1537
1538 let glyph_ids = unsafe { std::slice::from_raw_parts(glyphrun.glyphIndices, glyph_count) };
1539 let glyph_advances =
1540 unsafe { std::slice::from_raw_parts(glyphrun.glyphAdvances, glyph_count) };
1541 let glyph_offsets =
1542 unsafe { std::slice::from_raw_parts(glyphrun.glyphOffsets, glyph_count) };
1543 let cluster_map =
1544 unsafe { std::slice::from_raw_parts(desc.clusterMap, desc.stringLength as usize) };
1545
1546 let mut cluster_analyzer = ClusterAnalyzer::new(cluster_map, glyph_count);
1547 let mut utf16_idx = desc.textPosition as usize;
1548 let mut glyph_idx = 0;
1549 let mut glyphs = Vec::with_capacity(glyph_count);
1550 for (cluster_utf16_len, cluster_glyph_count) in cluster_analyzer {
1551 context.index_converter.advance_to_utf16_ix(utf16_idx);
1552 utf16_idx += cluster_utf16_len;
1553 for (cluster_glyph_idx, glyph_id) in glyph_ids
1554 [glyph_idx..(glyph_idx + cluster_glyph_count)]
1555 .iter()
1556 .enumerate()
1557 {
1558 let id = GlyphId(*glyph_id as u32);
1559 let is_emoji = color_font
1560 && is_color_glyph(font_face, id, &context.text_system.components.factory);
1561 let this_glyph_idx = glyph_idx + cluster_glyph_idx;
1562 glyphs.push(ShapedGlyph {
1563 id,
1564 position: point(
1565 px(context.width + glyph_offsets[this_glyph_idx].advanceOffset),
1566 px(0.0),
1567 ),
1568 index: context.index_converter.utf8_ix,
1569 is_emoji,
1570 });
1571 context.width += glyph_advances[this_glyph_idx];
1572 }
1573 glyph_idx += cluster_glyph_count;
1574 }
1575 context.runs.push(ShapedRun { font_id, glyphs });
1576 Ok(())
1577 }
1578
1579 fn DrawUnderline(
1580 &self,
1581 _clientdrawingcontext: *const ::core::ffi::c_void,
1582 _baselineoriginx: f32,
1583 _baselineoriginy: f32,
1584 _underline: *const DWRITE_UNDERLINE,
1585 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1586 ) -> windows::core::Result<()> {
1587 Err(windows::core::Error::new(
1588 E_NOTIMPL,
1589 "DrawUnderline unimplemented",
1590 ))
1591 }
1592
1593 fn DrawStrikethrough(
1594 &self,
1595 _clientdrawingcontext: *const ::core::ffi::c_void,
1596 _baselineoriginx: f32,
1597 _baselineoriginy: f32,
1598 _strikethrough: *const DWRITE_STRIKETHROUGH,
1599 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1600 ) -> windows::core::Result<()> {
1601 Err(windows::core::Error::new(
1602 E_NOTIMPL,
1603 "DrawStrikethrough unimplemented",
1604 ))
1605 }
1606
1607 fn DrawInlineObject(
1608 &self,
1609 _clientdrawingcontext: *const ::core::ffi::c_void,
1610 _originx: f32,
1611 _originy: f32,
1612 _inlineobject: windows::core::Ref<IDWriteInlineObject>,
1613 _issideways: BOOL,
1614 _isrighttoleft: BOOL,
1615 _clientdrawingeffect: windows::core::Ref<windows::core::IUnknown>,
1616 ) -> windows::core::Result<()> {
1617 Err(windows::core::Error::new(
1618 E_NOTIMPL,
1619 "DrawInlineObject unimplemented",
1620 ))
1621 }
1622}
1623
1624struct StringIndexConverter<'a> {
1625 text: &'a str,
1626 utf8_ix: usize,
1627 utf16_ix: usize,
1628}
1629
1630impl<'a> StringIndexConverter<'a> {
1631 fn new(text: &'a str) -> Self {
1632 Self {
1633 text,
1634 utf8_ix: 0,
1635 utf16_ix: 0,
1636 }
1637 }
1638
1639 #[allow(dead_code)]
1640 fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
1641 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1642 if self.utf8_ix + ix >= utf8_target {
1643 self.utf8_ix += ix;
1644 return;
1645 }
1646 self.utf16_ix += c.len_utf16();
1647 }
1648 self.utf8_ix = self.text.len();
1649 }
1650
1651 fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
1652 for (ix, c) in self.text[self.utf8_ix..].char_indices() {
1653 if self.utf16_ix >= utf16_target {
1654 self.utf8_ix += ix;
1655 return;
1656 }
1657 self.utf16_ix += c.len_utf16();
1658 }
1659 self.utf8_ix = self.text.len();
1660 }
1661}
1662
1663impl Into<DWRITE_FONT_STYLE> for FontStyle {
1664 fn into(self) -> DWRITE_FONT_STYLE {
1665 match self {
1666 FontStyle::Normal => DWRITE_FONT_STYLE_NORMAL,
1667 FontStyle::Italic => DWRITE_FONT_STYLE_ITALIC,
1668 FontStyle::Oblique => DWRITE_FONT_STYLE_OBLIQUE,
1669 }
1670 }
1671}
1672
1673impl From<DWRITE_FONT_STYLE> for FontStyle {
1674 fn from(value: DWRITE_FONT_STYLE) -> Self {
1675 match value.0 {
1676 0 => FontStyle::Normal,
1677 1 => FontStyle::Italic,
1678 2 => FontStyle::Oblique,
1679 _ => unreachable!(),
1680 }
1681 }
1682}
1683
1684impl Into<DWRITE_FONT_WEIGHT> for FontWeight {
1685 fn into(self) -> DWRITE_FONT_WEIGHT {
1686 DWRITE_FONT_WEIGHT(self.0 as i32)
1687 }
1688}
1689
1690impl From<DWRITE_FONT_WEIGHT> for FontWeight {
1691 fn from(value: DWRITE_FONT_WEIGHT) -> Self {
1692 FontWeight(value.0 as f32)
1693 }
1694}
1695
1696fn get_font_names_from_collection(
1697 collection: &IDWriteFontCollection1,
1698 locale: &str,
1699) -> Vec<String> {
1700 unsafe {
1701 let mut result = Vec::new();
1702 let family_count = collection.GetFontFamilyCount();
1703 for index in 0..family_count {
1704 let Some(font_family) = collection.GetFontFamily(index).log_err() else {
1705 continue;
1706 };
1707 let Some(localized_family_name) = font_family.GetFamilyNames().log_err() else {
1708 continue;
1709 };
1710 let Some(family_name) = get_name(localized_family_name, locale).log_err() else {
1711 continue;
1712 };
1713 result.push(family_name);
1714 }
1715
1716 result
1717 }
1718}
1719
1720fn get_font_identifier_and_font_struct(
1721 font_face: &IDWriteFontFace3,
1722 locale: &str,
1723) -> Option<(FontIdentifier, Font, bool)> {
1724 let postscript_name = get_postscript_name(font_face, locale).log_err()?;
1725 let localized_family_name = unsafe { font_face.GetFamilyNames().log_err() }?;
1726 let family_name = get_name(localized_family_name, locale).log_err()?;
1727 let weight = unsafe { font_face.GetWeight() };
1728 let style = unsafe { font_face.GetStyle() };
1729 let identifier = FontIdentifier {
1730 postscript_name,
1731 weight: weight.0,
1732 style: style.0,
1733 };
1734 let font_struct = Font {
1735 family: family_name.into(),
1736 features: FontFeatures::default(),
1737 weight: weight.into(),
1738 style: style.into(),
1739 fallbacks: None,
1740 };
1741 let is_emoji = unsafe { font_face.IsColorFont().as_bool() };
1742 Some((identifier, font_struct, is_emoji))
1743}
1744
1745#[inline]
1746fn get_font_identifier(font_face: &IDWriteFontFace3, locale: &str) -> Option<FontIdentifier> {
1747 let weight = unsafe { font_face.GetWeight().0 };
1748 let style = unsafe { font_face.GetStyle().0 };
1749 get_postscript_name(font_face, locale)
1750 .log_err()
1751 .map(|postscript_name| FontIdentifier {
1752 postscript_name,
1753 weight,
1754 style,
1755 })
1756}
1757
1758#[inline]
1759fn get_postscript_name(font_face: &IDWriteFontFace3, locale: &str) -> Result<String> {
1760 let mut info = None;
1761 let mut exists = BOOL(0);
1762 unsafe {
1763 font_face.GetInformationalStrings(
1764 DWRITE_INFORMATIONAL_STRING_POSTSCRIPT_NAME,
1765 &mut info,
1766 &mut exists,
1767 )?
1768 };
1769 if !exists.as_bool() || info.is_none() {
1770 anyhow::bail!("No postscript name found for font face");
1771 }
1772
1773 get_name(info.unwrap(), locale)
1774}
1775
1776// https://learn.microsoft.com/en-us/windows/win32/api/dwrite/ne-dwrite-dwrite_font_feature_tag
1777fn apply_font_features(
1778 direct_write_features: &IDWriteTypography,
1779 features: &FontFeatures,
1780) -> Result<()> {
1781 let tag_values = features.tag_value_list();
1782 if tag_values.is_empty() {
1783 return Ok(());
1784 }
1785
1786 // All of these features are enabled by default by DirectWrite.
1787 // If you want to (and can) peek into the source of DirectWrite
1788 let mut feature_liga = make_direct_write_feature("liga", 1);
1789 let mut feature_clig = make_direct_write_feature("clig", 1);
1790 let mut feature_calt = make_direct_write_feature("calt", 1);
1791
1792 for (tag, value) in tag_values {
1793 if tag.as_str() == "liga" && *value == 0 {
1794 feature_liga.parameter = 0;
1795 continue;
1796 }
1797 if tag.as_str() == "clig" && *value == 0 {
1798 feature_clig.parameter = 0;
1799 continue;
1800 }
1801 if tag.as_str() == "calt" && *value == 0 {
1802 feature_calt.parameter = 0;
1803 continue;
1804 }
1805
1806 unsafe {
1807 direct_write_features.AddFontFeature(make_direct_write_feature(&tag, *value))?;
1808 }
1809 }
1810 unsafe {
1811 direct_write_features.AddFontFeature(feature_liga)?;
1812 direct_write_features.AddFontFeature(feature_clig)?;
1813 direct_write_features.AddFontFeature(feature_calt)?;
1814 }
1815
1816 Ok(())
1817}
1818
1819#[inline]
1820const fn make_direct_write_feature(feature_name: &str, parameter: u32) -> DWRITE_FONT_FEATURE {
1821 let tag = make_direct_write_tag(feature_name);
1822 DWRITE_FONT_FEATURE {
1823 nameTag: tag,
1824 parameter,
1825 }
1826}
1827
1828#[inline]
1829const fn make_open_type_tag(tag_name: &str) -> u32 {
1830 let bytes = tag_name.as_bytes();
1831 debug_assert!(bytes.len() == 4);
1832 u32::from_le_bytes([bytes[0], bytes[1], bytes[2], bytes[3]])
1833}
1834
1835#[inline]
1836const fn make_direct_write_tag(tag_name: &str) -> DWRITE_FONT_FEATURE_TAG {
1837 DWRITE_FONT_FEATURE_TAG(make_open_type_tag(tag_name))
1838}
1839
1840#[inline]
1841fn get_name(string: IDWriteLocalizedStrings, locale: &str) -> Result<String> {
1842 let mut locale_name_index = 0u32;
1843 let mut exists = BOOL(0);
1844 unsafe {
1845 string.FindLocaleName(
1846 &HSTRING::from(locale),
1847 &mut locale_name_index,
1848 &mut exists as _,
1849 )?
1850 };
1851 if !exists.as_bool() {
1852 unsafe {
1853 string.FindLocaleName(
1854 DEFAULT_LOCALE_NAME,
1855 &mut locale_name_index as _,
1856 &mut exists as _,
1857 )?
1858 };
1859 anyhow::ensure!(exists.as_bool(), "No localised string for {locale}");
1860 }
1861
1862 let name_length = unsafe { string.GetStringLength(locale_name_index) }? as usize;
1863 let mut name_vec = vec![0u16; name_length + 1];
1864 unsafe {
1865 string.GetString(locale_name_index, &mut name_vec)?;
1866 }
1867
1868 Ok(String::from_utf16_lossy(&name_vec[..name_length]))
1869}
1870
1871fn get_system_ui_font_name() -> SharedString {
1872 unsafe {
1873 let mut info: LOGFONTW = std::mem::zeroed();
1874 let font_family = if SystemParametersInfoW(
1875 SPI_GETICONTITLELOGFONT,
1876 std::mem::size_of::<LOGFONTW>() as u32,
1877 Some(&mut info as *mut _ as _),
1878 SYSTEM_PARAMETERS_INFO_UPDATE_FLAGS(0),
1879 )
1880 .log_err()
1881 .is_none()
1882 {
1883 // https://learn.microsoft.com/en-us/windows/win32/uxguide/vis-fonts
1884 // Segoe UI is the Windows font intended for user interface text strings.
1885 "Segoe UI".into()
1886 } else {
1887 let font_name = String::from_utf16_lossy(&info.lfFaceName);
1888 font_name.trim_matches(char::from(0)).to_owned().into()
1889 };
1890 log::info!("Use {} as UI font.", font_family);
1891 font_family
1892 }
1893}
1894
1895// One would think that with newer DirectWrite method: IDWriteFontFace4::GetGlyphImageFormats
1896// but that doesn't seem to work for some glyphs, say ❤
1897fn is_color_glyph(
1898 font_face: &IDWriteFontFace3,
1899 glyph_id: GlyphId,
1900 factory: &IDWriteFactory5,
1901) -> bool {
1902 let glyph_run = DWRITE_GLYPH_RUN {
1903 fontFace: unsafe { std::mem::transmute_copy(font_face) },
1904 fontEmSize: 14.0,
1905 glyphCount: 1,
1906 glyphIndices: &(glyph_id.0 as u16),
1907 glyphAdvances: &0.0,
1908 glyphOffsets: &DWRITE_GLYPH_OFFSET {
1909 advanceOffset: 0.0,
1910 ascenderOffset: 0.0,
1911 },
1912 isSideways: BOOL(0),
1913 bidiLevel: 0,
1914 };
1915 unsafe {
1916 factory.TranslateColorGlyphRun(
1917 Vector2::default(),
1918 &glyph_run as _,
1919 None,
1920 DWRITE_GLYPH_IMAGE_FORMATS_COLR
1921 | DWRITE_GLYPH_IMAGE_FORMATS_SVG
1922 | DWRITE_GLYPH_IMAGE_FORMATS_PNG
1923 | DWRITE_GLYPH_IMAGE_FORMATS_JPEG
1924 | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8,
1925 DWRITE_MEASURING_MODE_NATURAL,
1926 None,
1927 0,
1928 )
1929 }
1930 .is_ok()
1931}
1932
1933const DEFAULT_LOCALE_NAME: PCWSTR = windows::core::w!("en-US");
1934
1935#[cfg(test)]
1936mod tests {
1937 use crate::platform::windows::direct_write::ClusterAnalyzer;
1938
1939 #[test]
1940 fn test_cluster_map() {
1941 let cluster_map = [0];
1942 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 1);
1943 let next = analyzer.next();
1944 assert_eq!(next, Some((1, 1)));
1945 let next = analyzer.next();
1946 assert_eq!(next, None);
1947
1948 let cluster_map = [0, 1, 2];
1949 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 3);
1950 let next = analyzer.next();
1951 assert_eq!(next, Some((1, 1)));
1952 let next = analyzer.next();
1953 assert_eq!(next, Some((1, 1)));
1954 let next = analyzer.next();
1955 assert_eq!(next, Some((1, 1)));
1956 let next = analyzer.next();
1957 assert_eq!(next, None);
1958 // 👨👩👧👦👩💻
1959 let cluster_map = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 4, 4, 4];
1960 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 5);
1961 let next = analyzer.next();
1962 assert_eq!(next, Some((11, 4)));
1963 let next = analyzer.next();
1964 assert_eq!(next, Some((5, 1)));
1965 let next = analyzer.next();
1966 assert_eq!(next, None);
1967 // 👩💻
1968 let cluster_map = [0, 0, 0, 0, 0];
1969 let mut analyzer = ClusterAnalyzer::new(&cluster_map, 1);
1970 let next = analyzer.next();
1971 assert_eq!(next, Some((5, 1)));
1972 let next = analyzer.next();
1973 assert_eq!(next, None);
1974 }
1975}