use std::{borrow::Cow, sync::Arc}; use ::util::ResultExt; use anyhow::{anyhow, Result}; use collections::HashMap; use itertools::Itertools; use parking_lot::{RwLock, RwLockUpgradableReadGuard}; use smallvec::SmallVec; use windows::{ core::*, Win32::{ Foundation::*, Globalization::GetUserDefaultLocaleName, Graphics::{ Direct2D::{Common::*, *}, DirectWrite::*, Dxgi::Common::*, Gdi::LOGFONTW, Imaging::*, }, System::SystemServices::LOCALE_NAME_MAX_LENGTH, UI::WindowsAndMessaging::*, }, }; use windows_numerics::Vector2; use crate::*; #[derive(Debug)] struct FontInfo { font_family: String, font_face: IDWriteFontFace3, features: IDWriteTypography, fallbacks: Option, is_system_font: bool, is_emoji: bool, } pub(crate) struct DirectWriteTextSystem(RwLock); struct DirectWriteComponent { locale: String, factory: IDWriteFactory5, bitmap_factory: AgileReference, d2d1_factory: ID2D1Factory, in_memory_loader: IDWriteInMemoryFontFileLoader, builder: IDWriteFontSetBuilder1, text_renderer: Arc, render_context: GlyphRenderContext, } struct GlyphRenderContext { params: IDWriteRenderingParams3, dc_target: ID2D1DeviceContext4, } struct DirectWriteState { components: DirectWriteComponent, system_ui_font_name: SharedString, system_font_collection: IDWriteFontCollection1, custom_font_collection: IDWriteFontCollection1, fonts: Vec, font_selections: HashMap, font_id_by_identifier: HashMap, } #[derive(Debug, Clone, Hash, PartialEq, Eq)] struct FontIdentifier { postscript_name: String, weight: i32, style: i32, } impl DirectWriteComponent { pub fn new(bitmap_factory: &IWICImagingFactory) -> Result { unsafe { let factory: IDWriteFactory5 = DWriteCreateFactory(DWRITE_FACTORY_TYPE_SHARED)?; let bitmap_factory = AgileReference::new(bitmap_factory)?; let d2d1_factory: ID2D1Factory = D2D1CreateFactory(D2D1_FACTORY_TYPE_MULTI_THREADED, None)?; // The `IDWriteInMemoryFontFileLoader` here is supported starting from // Windows 10 Creators Update, which consequently requires the entire // `DirectWriteTextSystem` to run on `win10 1703`+. let in_memory_loader = factory.CreateInMemoryFontFileLoader()?; factory.RegisterFontFileLoader(&in_memory_loader)?; let builder = factory.CreateFontSetBuilder()?; let mut locale_vec = vec![0u16; LOCALE_NAME_MAX_LENGTH as usize]; GetUserDefaultLocaleName(&mut locale_vec); let locale = String::from_utf16_lossy(&locale_vec); let text_renderer = Arc::new(TextRendererWrapper::new(&locale)); let render_context = GlyphRenderContext::new(&factory, &d2d1_factory)?; Ok(DirectWriteComponent { locale, factory, bitmap_factory, d2d1_factory, in_memory_loader, builder, text_renderer, render_context, }) } } } impl GlyphRenderContext { pub fn new(factory: &IDWriteFactory5, d2d1_factory: &ID2D1Factory) -> Result { unsafe { let default_params: IDWriteRenderingParams3 = factory.CreateRenderingParams()?.cast()?; let gamma = default_params.GetGamma(); let enhanced_contrast = default_params.GetEnhancedContrast(); let gray_contrast = default_params.GetGrayscaleEnhancedContrast(); let cleartype_level = default_params.GetClearTypeLevel(); let grid_fit_mode = default_params.GetGridFitMode(); let params = factory.CreateCustomRenderingParams( gamma, enhanced_contrast, gray_contrast, cleartype_level, DWRITE_PIXEL_GEOMETRY_RGB, DWRITE_RENDERING_MODE1_NATURAL_SYMMETRIC, grid_fit_mode, )?; let dc_target = { let target = d2d1_factory.CreateDCRenderTarget(&get_render_target_property( DXGI_FORMAT_B8G8R8A8_UNORM, D2D1_ALPHA_MODE_PREMULTIPLIED, ))?; let target = target.cast::()?; target.SetTextRenderingParams(¶ms); target }; Ok(Self { params, dc_target }) } } } impl DirectWriteTextSystem { pub(crate) fn new(bitmap_factory: &IWICImagingFactory) -> Result { let components = DirectWriteComponent::new(bitmap_factory)?; let system_font_collection = unsafe { let mut result = std::mem::zeroed(); components .factory .GetSystemFontCollection(false, &mut result, true)?; result.unwrap() }; let custom_font_set = unsafe { components.builder.CreateFontSet()? }; let custom_font_collection = unsafe { components .factory .CreateFontCollectionFromFontSet(&custom_font_set)? }; let system_ui_font_name = get_system_ui_font_name(); Ok(Self(RwLock::new(DirectWriteState { components, system_ui_font_name, system_font_collection, custom_font_collection, fonts: Vec::new(), font_selections: HashMap::default(), font_id_by_identifier: HashMap::default(), }))) } } impl PlatformTextSystem for DirectWriteTextSystem { fn add_fonts(&self, fonts: Vec>) -> Result<()> { self.0.write().add_fonts(fonts) } fn all_font_names(&self) -> Vec { self.0.read().all_font_names() } fn font_id(&self, font: &Font) -> Result { let lock = self.0.upgradable_read(); if let Some(font_id) = lock.font_selections.get(font) { Ok(*font_id) } else { let mut lock = RwLockUpgradableReadGuard::upgrade(lock); let font_id = lock.select_font(font); lock.font_selections.insert(font.clone(), font_id); Ok(font_id) } } fn font_metrics(&self, font_id: FontId) -> FontMetrics { self.0.read().font_metrics(font_id) } fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result> { self.0.read().get_typographic_bounds(font_id, glyph_id) } fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> anyhow::Result> { self.0.read().get_advance(font_id, glyph_id) } fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option { self.0.read().glyph_for_char(font_id, ch) } fn glyph_raster_bounds( &self, params: &RenderGlyphParams, ) -> anyhow::Result> { self.0.read().raster_bounds(params) } fn rasterize_glyph( &self, params: &RenderGlyphParams, raster_bounds: Bounds, ) -> anyhow::Result<(Size, Vec)> { self.0.read().rasterize_glyph(params, raster_bounds) } fn layout_line(&self, text: &str, font_size: Pixels, runs: &[FontRun]) -> LineLayout { self.0 .write() .layout_line(text, font_size, runs) .log_err() .unwrap_or(LineLayout { font_size, ..Default::default() }) } } impl DirectWriteState { fn add_fonts(&mut self, fonts: Vec>) -> Result<()> { for font_data in fonts { match font_data { Cow::Borrowed(data) => unsafe { let font_file = self .components .in_memory_loader .CreateInMemoryFontFileReference( &self.components.factory, data.as_ptr() as _, data.len() as _, None, )?; self.components.builder.AddFontFile(&font_file)?; }, Cow::Owned(data) => unsafe { let font_file = self .components .in_memory_loader .CreateInMemoryFontFileReference( &self.components.factory, data.as_ptr() as _, data.len() as _, None, )?; self.components.builder.AddFontFile(&font_file)?; }, } } let set = unsafe { self.components.builder.CreateFontSet()? }; let collection = unsafe { self.components .factory .CreateFontCollectionFromFontSet(&set)? }; self.custom_font_collection = collection; Ok(()) } fn generate_font_fallbacks( &self, fallbacks: &FontFallbacks, ) -> Result> { if fallbacks.fallback_list().is_empty() { return Ok(None); } unsafe { let builder = self.components.factory.CreateFontFallbackBuilder()?; let font_set = &self.system_font_collection.GetFontSet()?; for family_name in fallbacks.fallback_list() { let Some(fonts) = font_set .GetMatchingFonts( &HSTRING::from(family_name), DWRITE_FONT_WEIGHT_NORMAL, DWRITE_FONT_STRETCH_NORMAL, DWRITE_FONT_STYLE_NORMAL, ) .log_err() else { continue; }; if fonts.GetFontCount() == 0 { log::error!("No matching font found for {}", family_name); continue; } let font = fonts.GetFontFaceReference(0)?.CreateFontFace()?; let mut count = 0; font.GetUnicodeRanges(None, &mut count).ok(); if count == 0 { continue; } let mut unicode_ranges = vec![DWRITE_UNICODE_RANGE::default(); count as usize]; let Some(_) = font .GetUnicodeRanges(Some(&mut unicode_ranges), &mut count) .log_err() else { continue; }; let target_family_name = HSTRING::from(family_name); builder.AddMapping( &unicode_ranges, &[target_family_name.as_ptr()], None, None, None, 1.0, )?; } let system_fallbacks = self.components.factory.GetSystemFontFallback()?; builder.AddMappings(&system_fallbacks)?; Ok(Some(builder.CreateFontFallback()?)) } } unsafe fn generate_font_features( &self, font_features: &FontFeatures, ) -> Result { let direct_write_features = self.components.factory.CreateTypography()?; apply_font_features(&direct_write_features, font_features)?; Ok(direct_write_features) } unsafe fn get_font_id_from_font_collection( &mut self, family_name: &str, font_weight: FontWeight, font_style: FontStyle, font_features: &FontFeatures, font_fallbacks: Option<&FontFallbacks>, is_system_font: bool, ) -> Option { let collection = if is_system_font { &self.system_font_collection } else { &self.custom_font_collection }; let fontset = collection.GetFontSet().log_err()?; let font = fontset .GetMatchingFonts( &HSTRING::from(family_name), font_weight.into(), DWRITE_FONT_STRETCH_NORMAL, font_style.into(), ) .log_err()?; let total_number = font.GetFontCount(); for index in 0..total_number { let Some(font_face_ref) = font.GetFontFaceReference(index).log_err() else { continue; }; let Some(font_face) = font_face_ref.CreateFontFace().log_err() else { continue; }; let Some(identifier) = get_font_identifier(&font_face, &self.components.locale) else { continue; }; let is_emoji = font_face.IsColorFont().as_bool(); let Some(direct_write_features) = self.generate_font_features(font_features).log_err() else { continue; }; let fallbacks = font_fallbacks .and_then(|fallbacks| self.generate_font_fallbacks(fallbacks).log_err().flatten()); let font_info = FontInfo { font_family: family_name.to_owned(), font_face, features: direct_write_features, fallbacks, is_system_font, is_emoji, }; let font_id = FontId(self.fonts.len()); self.fonts.push(font_info); self.font_id_by_identifier.insert(identifier, font_id); return Some(font_id); } None } unsafe fn update_system_font_collection(&mut self) { let mut collection = std::mem::zeroed(); if self .components .factory .GetSystemFontCollection(false, &mut collection, true) .log_err() .is_some() { self.system_font_collection = collection.unwrap(); } } fn select_font(&mut self, target_font: &Font) -> FontId { unsafe { if target_font.family == ".SystemUIFont" { let family = self.system_ui_font_name.clone(); self.find_font_id( family.as_ref(), target_font.weight, target_font.style, &target_font.features, target_font.fallbacks.as_ref(), ) .unwrap() } else { self.find_font_id( target_font.family.as_ref(), target_font.weight, target_font.style, &target_font.features, target_font.fallbacks.as_ref(), ) .unwrap_or_else(|| { #[cfg(any(test, feature = "test-support"))] { panic!("ERROR: {} font not found!", target_font.family); } #[cfg(not(any(test, feature = "test-support")))] { let family = self.system_ui_font_name.clone(); log::error!("{} not found, use {} instead.", target_font.family, family); self.get_font_id_from_font_collection( family.as_ref(), target_font.weight, target_font.style, &target_font.features, target_font.fallbacks.as_ref(), true, ) .unwrap() } }) } } } unsafe fn find_font_id( &mut self, family_name: &str, weight: FontWeight, style: FontStyle, features: &FontFeatures, fallbacks: Option<&FontFallbacks>, ) -> Option { // try to find target font in custom font collection first self.get_font_id_from_font_collection( family_name, weight, style, features, fallbacks, false, ) .or_else(|| { self.get_font_id_from_font_collection( family_name, weight, style, features, fallbacks, true, ) }) .or_else(|| { self.update_system_font_collection(); self.get_font_id_from_font_collection( family_name, weight, style, features, fallbacks, true, ) }) } fn layout_line( &mut self, text: &str, font_size: Pixels, font_runs: &[FontRun], ) -> Result { if font_runs.is_empty() { return Ok(LineLayout { font_size, ..Default::default() }); } unsafe { let text_renderer = self.components.text_renderer.clone(); let text_wide = text.encode_utf16().collect_vec(); let mut utf8_offset = 0usize; let mut utf16_offset = 0u32; let text_layout = { let first_run = &font_runs[0]; let font_info = &self.fonts[first_run.font_id.0]; let collection = if font_info.is_system_font { &self.system_font_collection } else { &self.custom_font_collection }; let format: IDWriteTextFormat1 = self .components .factory .CreateTextFormat( &HSTRING::from(&font_info.font_family), collection, font_info.font_face.GetWeight(), font_info.font_face.GetStyle(), DWRITE_FONT_STRETCH_NORMAL, font_size.0, &HSTRING::from(&self.components.locale), )? .cast()?; if let Some(ref fallbacks) = font_info.fallbacks { format.SetFontFallback(fallbacks)?; } let layout = self.components.factory.CreateTextLayout( &text_wide, &format, f32::INFINITY, f32::INFINITY, )?; let current_text = &text[utf8_offset..(utf8_offset + first_run.len)]; utf8_offset += first_run.len; let current_text_utf16_length = current_text.encode_utf16().count() as u32; let text_range = DWRITE_TEXT_RANGE { startPosition: utf16_offset, length: current_text_utf16_length, }; layout.SetTypography(&font_info.features, text_range)?; utf16_offset += current_text_utf16_length; layout }; let mut first_run = true; let mut ascent = Pixels::default(); let mut descent = Pixels::default(); for run in font_runs { if first_run { first_run = false; let mut metrics = vec![DWRITE_LINE_METRICS::default(); 4]; let mut line_count = 0u32; text_layout.GetLineMetrics(Some(&mut metrics), &mut line_count as _)?; ascent = px(metrics[0].baseline); descent = px(metrics[0].height - metrics[0].baseline); continue; } let font_info = &self.fonts[run.font_id.0]; let current_text = &text[utf8_offset..(utf8_offset + run.len)]; utf8_offset += run.len; let current_text_utf16_length = current_text.encode_utf16().count() as u32; let collection = if font_info.is_system_font { &self.system_font_collection } else { &self.custom_font_collection }; let text_range = DWRITE_TEXT_RANGE { startPosition: utf16_offset, length: current_text_utf16_length, }; utf16_offset += current_text_utf16_length; text_layout.SetFontCollection(collection, text_range)?; text_layout .SetFontFamilyName(&HSTRING::from(&font_info.font_family), text_range)?; text_layout.SetFontSize(font_size.0, text_range)?; text_layout.SetFontStyle(font_info.font_face.GetStyle(), text_range)?; text_layout.SetFontWeight(font_info.font_face.GetWeight(), text_range)?; text_layout.SetTypography(&font_info.features, text_range)?; } let mut runs = Vec::new(); let renderer_context = RendererContext { text_system: self, index_converter: StringIndexConverter::new(text), runs: &mut runs, utf16_index: 0, width: 0.0, }; text_layout.Draw( Some(&renderer_context as *const _ as _), &text_renderer.0, 0.0, 0.0, )?; let width = px(renderer_context.width); Ok(LineLayout { font_size, width, ascent, descent, runs, len: text.len(), }) } } fn font_metrics(&self, font_id: FontId) -> FontMetrics { unsafe { let font_info = &self.fonts[font_id.0]; let mut metrics = std::mem::zeroed(); font_info.font_face.GetMetrics(&mut metrics); FontMetrics { units_per_em: metrics.Base.designUnitsPerEm as _, ascent: metrics.Base.ascent as _, descent: -(metrics.Base.descent as f32), line_gap: metrics.Base.lineGap as _, underline_position: metrics.Base.underlinePosition as _, underline_thickness: metrics.Base.underlineThickness as _, cap_height: metrics.Base.capHeight as _, x_height: metrics.Base.xHeight as _, bounding_box: Bounds { origin: Point { x: metrics.glyphBoxLeft as _, y: metrics.glyphBoxBottom as _, }, size: Size { width: (metrics.glyphBoxRight - metrics.glyphBoxLeft) as _, height: (metrics.glyphBoxTop - metrics.glyphBoxBottom) as _, }, }, } } } fn raster_bounds(&self, params: &RenderGlyphParams) -> Result> { let render_target = &self.components.render_context.dc_target; unsafe { render_target.SetUnitMode(D2D1_UNIT_MODE_DIPS); render_target.SetDpi(96.0 * params.scale_factor, 96.0 * params.scale_factor); } let font = &self.fonts[params.font_id.0]; let glyph_id = [params.glyph_id.0 as u16]; let advance = [0.0f32]; let offset = [DWRITE_GLYPH_OFFSET::default()]; let glyph_run = DWRITE_GLYPH_RUN { fontFace: unsafe { std::mem::transmute_copy(&font.font_face) }, fontEmSize: params.font_size.0, glyphCount: 1, glyphIndices: glyph_id.as_ptr(), glyphAdvances: advance.as_ptr(), glyphOffsets: offset.as_ptr(), isSideways: BOOL(0), bidiLevel: 0, }; let bounds = unsafe { render_target.GetGlyphRunWorldBounds( Vector2 { X: 0.0, Y: 0.0 }, &glyph_run, DWRITE_MEASURING_MODE_NATURAL, )? }; // todo(windows) // This is a walkaround, deleted when figured out. let y_offset; let extra_height; if params.is_emoji { y_offset = 0; extra_height = 0; } else { // make some room for scaler. y_offset = -1; extra_height = 2; } if bounds.right < bounds.left { Ok(Bounds { origin: point(0.into(), 0.into()), size: size(0.into(), 0.into()), }) } else { Ok(Bounds { origin: point( ((bounds.left * params.scale_factor).ceil() as i32).into(), ((bounds.top * params.scale_factor).ceil() as i32 + y_offset).into(), ), size: size( (((bounds.right - bounds.left) * params.scale_factor).ceil() as i32).into(), (((bounds.bottom - bounds.top) * params.scale_factor).ceil() as i32 + extra_height) .into(), ), }) } } fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option { let font_info = &self.fonts[font_id.0]; let codepoints = [ch as u32]; let mut glyph_indices = vec![0u16; 1]; unsafe { font_info .font_face .GetGlyphIndices(codepoints.as_ptr(), 1, glyph_indices.as_mut_ptr()) .log_err() } .map(|_| GlyphId(glyph_indices[0] as u32)) } fn rasterize_glyph( &self, params: &RenderGlyphParams, glyph_bounds: Bounds, ) -> Result<(Size, Vec)> { if glyph_bounds.size.width.0 == 0 || glyph_bounds.size.height.0 == 0 { return Err(anyhow!("glyph bounds are empty")); } let font_info = &self.fonts[params.font_id.0]; let glyph_id = [params.glyph_id.0 as u16]; let advance = [glyph_bounds.size.width.0 as f32]; let offset = [DWRITE_GLYPH_OFFSET { advanceOffset: -glyph_bounds.origin.x.0 as f32 / params.scale_factor, ascenderOffset: glyph_bounds.origin.y.0 as f32 / params.scale_factor, }]; let glyph_run = DWRITE_GLYPH_RUN { fontFace: unsafe { std::mem::transmute_copy(&font_info.font_face) }, fontEmSize: params.font_size.0, glyphCount: 1, glyphIndices: glyph_id.as_ptr(), glyphAdvances: advance.as_ptr(), glyphOffsets: offset.as_ptr(), isSideways: BOOL(0), bidiLevel: 0, }; // Add an extra pixel when the subpixel variant isn't zero to make room for anti-aliasing. let mut bitmap_size = glyph_bounds.size; if params.subpixel_variant.x > 0 { bitmap_size.width += DevicePixels(1); } if params.subpixel_variant.y > 0 { bitmap_size.height += DevicePixels(1); } let bitmap_size = bitmap_size; let total_bytes; let bitmap_format; let render_target_property; let bitmap_width; let bitmap_height; let bitmap_stride; let bitmap_dpi; if params.is_emoji { total_bytes = bitmap_size.height.0 as usize * bitmap_size.width.0 as usize * 4; bitmap_format = &GUID_WICPixelFormat32bppPBGRA; render_target_property = get_render_target_property( DXGI_FORMAT_B8G8R8A8_UNORM, D2D1_ALPHA_MODE_PREMULTIPLIED, ); bitmap_width = bitmap_size.width.0 as u32; bitmap_height = bitmap_size.height.0 as u32; bitmap_stride = bitmap_size.width.0 as u32 * 4; bitmap_dpi = 96.0; } else { total_bytes = bitmap_size.height.0 as usize * bitmap_size.width.0 as usize; bitmap_format = &GUID_WICPixelFormat8bppAlpha; render_target_property = get_render_target_property(DXGI_FORMAT_A8_UNORM, D2D1_ALPHA_MODE_STRAIGHT); bitmap_width = bitmap_size.width.0 as u32 * 2; bitmap_height = bitmap_size.height.0 as u32 * 2; bitmap_stride = bitmap_size.width.0 as u32; bitmap_dpi = 192.0; } let bitmap_factory = self.components.bitmap_factory.resolve()?; unsafe { let bitmap = bitmap_factory.CreateBitmap( bitmap_width, bitmap_height, bitmap_format, WICBitmapCacheOnLoad, )?; let render_target = self .components .d2d1_factory .CreateWicBitmapRenderTarget(&bitmap, &render_target_property)?; let brush = render_target.CreateSolidColorBrush(&BRUSH_COLOR, None)?; let subpixel_shift = params .subpixel_variant .map(|v| v as f32 / SUBPIXEL_VARIANTS as f32); let baseline_origin = Vector2 { X: subpixel_shift.x / params.scale_factor, Y: subpixel_shift.y / params.scale_factor, }; // This `cast()` action here should never fail since we are running on Win10+, and // ID2D1DeviceContext4 requires Win8+ let render_target = render_target.cast::().unwrap(); render_target.SetUnitMode(D2D1_UNIT_MODE_DIPS); render_target.SetDpi( bitmap_dpi * params.scale_factor, bitmap_dpi * params.scale_factor, ); render_target.SetTextRenderingParams(&self.components.render_context.params); render_target.BeginDraw(); if params.is_emoji { // WARN: only DWRITE_GLYPH_IMAGE_FORMATS_COLR has been tested let enumerator = self.components.factory.TranslateColorGlyphRun( baseline_origin, &glyph_run as _, None, DWRITE_GLYPH_IMAGE_FORMATS_COLR | DWRITE_GLYPH_IMAGE_FORMATS_SVG | DWRITE_GLYPH_IMAGE_FORMATS_PNG | DWRITE_GLYPH_IMAGE_FORMATS_JPEG | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8, DWRITE_MEASURING_MODE_NATURAL, None, 0, )?; while enumerator.MoveNext().is_ok() { let Ok(color_glyph) = enumerator.GetCurrentRun() else { break; }; let color_glyph = &*color_glyph; let brush_color = translate_color(&color_glyph.Base.runColor); brush.SetColor(&brush_color); match color_glyph.glyphImageFormat { DWRITE_GLYPH_IMAGE_FORMATS_PNG | DWRITE_GLYPH_IMAGE_FORMATS_JPEG | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8 => render_target .DrawColorBitmapGlyphRun( color_glyph.glyphImageFormat, baseline_origin, &color_glyph.Base.glyphRun, color_glyph.measuringMode, D2D1_COLOR_BITMAP_GLYPH_SNAP_OPTION_DEFAULT, ), DWRITE_GLYPH_IMAGE_FORMATS_SVG => render_target.DrawSvgGlyphRun( baseline_origin, &color_glyph.Base.glyphRun, &brush, None, color_glyph.Base.paletteIndex as u32, color_glyph.measuringMode, ), _ => render_target.DrawGlyphRun( baseline_origin, &color_glyph.Base.glyphRun, Some(color_glyph.Base.glyphRunDescription as *const _), &brush, color_glyph.measuringMode, ), } } } else { render_target.DrawGlyphRun( baseline_origin, &glyph_run, None, &brush, DWRITE_MEASURING_MODE_NATURAL, ); } render_target.EndDraw(None, None)?; let mut raw_data = vec![0u8; total_bytes]; if params.is_emoji { bitmap.CopyPixels(std::ptr::null() as _, bitmap_stride, &mut raw_data)?; // Convert from BGRA with premultiplied alpha to BGRA with straight alpha. for pixel in raw_data.chunks_exact_mut(4) { let a = pixel[3] as f32 / 255.; pixel[0] = (pixel[0] as f32 / a) as u8; pixel[1] = (pixel[1] as f32 / a) as u8; pixel[2] = (pixel[2] as f32 / a) as u8; } } else { let scaler = bitmap_factory.CreateBitmapScaler()?; scaler.Initialize( &bitmap, bitmap_size.width.0 as u32, bitmap_size.height.0 as u32, WICBitmapInterpolationModeHighQualityCubic, )?; scaler.CopyPixels(std::ptr::null() as _, bitmap_stride, &mut raw_data)?; } Ok((bitmap_size, raw_data)) } } fn get_typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result> { unsafe { let font = &self.fonts[font_id.0].font_face; let glyph_indices = [glyph_id.0 as u16]; let mut metrics = [DWRITE_GLYPH_METRICS::default()]; font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?; let metrics = &metrics[0]; let advance_width = metrics.advanceWidth as i32; let advance_height = metrics.advanceHeight as i32; let left_side_bearing = metrics.leftSideBearing; let right_side_bearing = metrics.rightSideBearing; let top_side_bearing = metrics.topSideBearing; let bottom_side_bearing = metrics.bottomSideBearing; let vertical_origin_y = metrics.verticalOriginY; let y_offset = vertical_origin_y + bottom_side_bearing - advance_height; let width = advance_width - (left_side_bearing + right_side_bearing); let height = advance_height - (top_side_bearing + bottom_side_bearing); Ok(Bounds { origin: Point { x: left_side_bearing as f32, y: y_offset as f32, }, size: Size { width: width as f32, height: height as f32, }, }) } } fn get_advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result> { unsafe { let font = &self.fonts[font_id.0].font_face; let glyph_indices = [glyph_id.0 as u16]; let mut metrics = [DWRITE_GLYPH_METRICS::default()]; font.GetDesignGlyphMetrics(glyph_indices.as_ptr(), 1, metrics.as_mut_ptr(), false)?; let metrics = &metrics[0]; Ok(Size { width: metrics.advanceWidth as f32, height: 0.0, }) } } fn all_font_names(&self) -> Vec { let mut result = get_font_names_from_collection(&self.system_font_collection, &self.components.locale); result.extend(get_font_names_from_collection( &self.custom_font_collection, &self.components.locale, )); result } } impl Drop for DirectWriteState { fn drop(&mut self) { unsafe { let _ = self .components .factory .UnregisterFontFileLoader(&self.components.in_memory_loader); } } } struct TextRendererWrapper(pub IDWriteTextRenderer); impl TextRendererWrapper { pub fn new(locale_str: &str) -> Self { let inner = TextRenderer::new(locale_str); TextRendererWrapper(inner.into()) } } #[implement(IDWriteTextRenderer)] struct TextRenderer { locale: String, } impl TextRenderer { pub fn new(locale_str: &str) -> Self { TextRenderer { locale: locale_str.to_owned(), } } } struct RendererContext<'t, 'a, 'b> { text_system: &'t mut DirectWriteState, index_converter: StringIndexConverter<'a>, runs: &'b mut Vec, utf16_index: usize, width: f32, } #[allow(non_snake_case)] impl IDWritePixelSnapping_Impl for TextRenderer_Impl { fn IsPixelSnappingDisabled( &self, _clientdrawingcontext: *const ::core::ffi::c_void, ) -> windows::core::Result { Ok(BOOL(0)) } fn GetCurrentTransform( &self, _clientdrawingcontext: *const ::core::ffi::c_void, transform: *mut DWRITE_MATRIX, ) -> windows::core::Result<()> { unsafe { *transform = DWRITE_MATRIX { m11: 1.0, m12: 0.0, m21: 0.0, m22: 1.0, dx: 0.0, dy: 0.0, }; } Ok(()) } fn GetPixelsPerDip( &self, _clientdrawingcontext: *const ::core::ffi::c_void, ) -> windows::core::Result { Ok(1.0) } } #[allow(non_snake_case)] impl IDWriteTextRenderer_Impl for TextRenderer_Impl { fn DrawGlyphRun( &self, clientdrawingcontext: *const ::core::ffi::c_void, _baselineoriginx: f32, _baselineoriginy: f32, _measuringmode: DWRITE_MEASURING_MODE, glyphrun: *const DWRITE_GLYPH_RUN, glyphrundescription: *const DWRITE_GLYPH_RUN_DESCRIPTION, _clientdrawingeffect: windows::core::Ref, ) -> windows::core::Result<()> { unsafe { let glyphrun = &*glyphrun; let glyph_count = glyphrun.glyphCount as usize; if glyph_count == 0 { return Ok(()); } let desc = &*glyphrundescription; let utf16_length_per_glyph = desc.stringLength as usize / glyph_count; let context = &mut *(clientdrawingcontext as *const RendererContext as *mut RendererContext); if glyphrun.fontFace.is_none() { return Ok(()); } let font_face = glyphrun.fontFace.as_ref().unwrap(); // This `cast()` action here should never fail since we are running on Win10+, and // `IDWriteFontFace3` requires Win10 let font_face = &font_face.cast::().unwrap(); let Some((font_identifier, font_struct, color_font)) = get_font_identifier_and_font_struct(font_face, &self.locale) else { return Ok(()); }; let font_id = if let Some(id) = context .text_system .font_id_by_identifier .get(&font_identifier) { *id } else { context.text_system.select_font(&font_struct) }; let mut glyphs = SmallVec::new(); for index in 0..glyph_count { let id = GlyphId(*glyphrun.glyphIndices.add(index) as u32); context .index_converter .advance_to_utf16_ix(context.utf16_index); let is_emoji = color_font && is_color_glyph(font_face, id, &context.text_system.components.factory); glyphs.push(ShapedGlyph { id, position: point(px(context.width), px(0.0)), index: context.index_converter.utf8_ix, is_emoji, }); context.utf16_index += utf16_length_per_glyph; context.width += *glyphrun.glyphAdvances.add(index); } context.runs.push(ShapedRun { font_id, glyphs }); } Ok(()) } fn DrawUnderline( &self, _clientdrawingcontext: *const ::core::ffi::c_void, _baselineoriginx: f32, _baselineoriginy: f32, _underline: *const DWRITE_UNDERLINE, _clientdrawingeffect: windows::core::Ref, ) -> windows::core::Result<()> { Err(windows::core::Error::new( E_NOTIMPL, "DrawUnderline unimplemented", )) } fn DrawStrikethrough( &self, _clientdrawingcontext: *const ::core::ffi::c_void, _baselineoriginx: f32, _baselineoriginy: f32, _strikethrough: *const DWRITE_STRIKETHROUGH, _clientdrawingeffect: windows::core::Ref, ) -> windows::core::Result<()> { Err(windows::core::Error::new( E_NOTIMPL, "DrawStrikethrough unimplemented", )) } fn DrawInlineObject( &self, _clientdrawingcontext: *const ::core::ffi::c_void, _originx: f32, _originy: f32, _inlineobject: windows::core::Ref, _issideways: BOOL, _isrighttoleft: BOOL, _clientdrawingeffect: windows::core::Ref, ) -> windows::core::Result<()> { Err(windows::core::Error::new( E_NOTIMPL, "DrawInlineObject unimplemented", )) } } struct StringIndexConverter<'a> { text: &'a str, utf8_ix: usize, utf16_ix: usize, } impl<'a> StringIndexConverter<'a> { fn new(text: &'a str) -> Self { Self { text, utf8_ix: 0, utf16_ix: 0, } } fn advance_to_utf8_ix(&mut self, utf8_target: usize) { for (ix, c) in self.text[self.utf8_ix..].char_indices() { if self.utf8_ix + ix >= utf8_target { self.utf8_ix += ix; return; } self.utf16_ix += c.len_utf16(); } self.utf8_ix = self.text.len(); } fn advance_to_utf16_ix(&mut self, utf16_target: usize) { for (ix, c) in self.text[self.utf8_ix..].char_indices() { if self.utf16_ix >= utf16_target { self.utf8_ix += ix; return; } self.utf16_ix += c.len_utf16(); } self.utf8_ix = self.text.len(); } } impl Into for FontStyle { fn into(self) -> DWRITE_FONT_STYLE { match self { FontStyle::Normal => DWRITE_FONT_STYLE_NORMAL, FontStyle::Italic => DWRITE_FONT_STYLE_ITALIC, FontStyle::Oblique => DWRITE_FONT_STYLE_OBLIQUE, } } } impl From for FontStyle { fn from(value: DWRITE_FONT_STYLE) -> Self { match value.0 { 0 => FontStyle::Normal, 1 => FontStyle::Italic, 2 => FontStyle::Oblique, _ => unreachable!(), } } } impl Into for FontWeight { fn into(self) -> DWRITE_FONT_WEIGHT { DWRITE_FONT_WEIGHT(self.0 as i32) } } impl From for FontWeight { fn from(value: DWRITE_FONT_WEIGHT) -> Self { FontWeight(value.0 as f32) } } fn get_font_names_from_collection( collection: &IDWriteFontCollection1, locale: &str, ) -> Vec { unsafe { let mut result = Vec::new(); let family_count = collection.GetFontFamilyCount(); for index in 0..family_count { let Some(font_family) = collection.GetFontFamily(index).log_err() else { continue; }; let Some(localized_family_name) = font_family.GetFamilyNames().log_err() else { continue; }; let Some(family_name) = get_name(localized_family_name, locale).log_err() else { continue; }; result.push(family_name); } result } } fn get_font_identifier_and_font_struct( font_face: &IDWriteFontFace3, locale: &str, ) -> Option<(FontIdentifier, Font, bool)> { let postscript_name = get_postscript_name(font_face, locale).log_err()?; let localized_family_name = unsafe { font_face.GetFamilyNames().log_err() }?; let family_name = get_name(localized_family_name, locale).log_err()?; let weight = unsafe { font_face.GetWeight() }; let style = unsafe { font_face.GetStyle() }; let identifier = FontIdentifier { postscript_name, weight: weight.0, style: style.0, }; let font_struct = Font { family: family_name.into(), features: FontFeatures::default(), weight: weight.into(), style: style.into(), fallbacks: None, }; let is_emoji = unsafe { font_face.IsColorFont().as_bool() }; Some((identifier, font_struct, is_emoji)) } #[inline] fn get_font_identifier(font_face: &IDWriteFontFace3, locale: &str) -> Option { let weight = unsafe { font_face.GetWeight().0 }; let style = unsafe { font_face.GetStyle().0 }; get_postscript_name(font_face, locale) .log_err() .map(|postscript_name| FontIdentifier { postscript_name, weight, style, }) } #[inline] fn get_postscript_name(font_face: &IDWriteFontFace3, locale: &str) -> Result { let mut info = None; let mut exists = BOOL(0); unsafe { font_face.GetInformationalStrings( DWRITE_INFORMATIONAL_STRING_POSTSCRIPT_NAME, &mut info, &mut exists, )? }; if !exists.as_bool() || info.is_none() { return Err(anyhow!("No postscript name found for font face")); } get_name(info.unwrap(), locale) } // https://learn.microsoft.com/en-us/windows/win32/api/dwrite/ne-dwrite-dwrite_font_feature_tag fn apply_font_features( direct_write_features: &IDWriteTypography, features: &FontFeatures, ) -> Result<()> { let tag_values = features.tag_value_list(); if tag_values.is_empty() { return Ok(()); } // All of these features are enabled by default by DirectWrite. // If you want to (and can) peek into the source of DirectWrite let mut feature_liga = make_direct_write_feature("liga", 1); let mut feature_clig = make_direct_write_feature("clig", 1); let mut feature_calt = make_direct_write_feature("calt", 1); for (tag, value) in tag_values { if tag.as_str() == "liga" && *value == 0 { feature_liga.parameter = 0; continue; } if tag.as_str() == "clig" && *value == 0 { feature_clig.parameter = 0; continue; } if tag.as_str() == "calt" && *value == 0 { feature_calt.parameter = 0; continue; } unsafe { direct_write_features.AddFontFeature(make_direct_write_feature(&tag, *value))?; } } unsafe { direct_write_features.AddFontFeature(feature_liga)?; direct_write_features.AddFontFeature(feature_clig)?; direct_write_features.AddFontFeature(feature_calt)?; } Ok(()) } #[inline] fn make_direct_write_feature(feature_name: &str, parameter: u32) -> DWRITE_FONT_FEATURE { let tag = make_direct_write_tag(feature_name); DWRITE_FONT_FEATURE { nameTag: tag, parameter, } } #[inline] fn make_open_type_tag(tag_name: &str) -> u32 { let bytes = tag_name.bytes().collect_vec(); assert_eq!(bytes.len(), 4); ((bytes[3] as u32) << 24) | ((bytes[2] as u32) << 16) | ((bytes[1] as u32) << 8) | (bytes[0] as u32) } #[inline] fn make_direct_write_tag(tag_name: &str) -> DWRITE_FONT_FEATURE_TAG { DWRITE_FONT_FEATURE_TAG(make_open_type_tag(tag_name)) } #[inline] fn get_name(string: IDWriteLocalizedStrings, locale: &str) -> Result { let mut locale_name_index = 0u32; let mut exists = BOOL(0); unsafe { string.FindLocaleName( &HSTRING::from(locale), &mut locale_name_index, &mut exists as _, )? }; if !exists.as_bool() { unsafe { string.FindLocaleName( DEFAULT_LOCALE_NAME, &mut locale_name_index as _, &mut exists as _, )? }; if !exists.as_bool() { return Err(anyhow!("No localised string for {}", locale)); } } let name_length = unsafe { string.GetStringLength(locale_name_index) }? as usize; let mut name_vec = vec![0u16; name_length + 1]; unsafe { string.GetString(locale_name_index, &mut name_vec)?; } Ok(String::from_utf16_lossy(&name_vec[..name_length])) } #[inline] fn translate_color(color: &DWRITE_COLOR_F) -> D2D1_COLOR_F { D2D1_COLOR_F { r: color.r, g: color.g, b: color.b, a: color.a, } } fn get_system_ui_font_name() -> SharedString { unsafe { let mut info: LOGFONTW = std::mem::zeroed(); let font_family = if SystemParametersInfoW( SPI_GETICONTITLELOGFONT, std::mem::size_of::() as u32, Some(&mut info as *mut _ as _), SYSTEM_PARAMETERS_INFO_UPDATE_FLAGS(0), ) .log_err() .is_none() { // https://learn.microsoft.com/en-us/windows/win32/uxguide/vis-fonts // Segoe UI is the Windows font intended for user interface text strings. "Segoe UI".into() } else { let font_name = String::from_utf16_lossy(&info.lfFaceName); font_name.trim_matches(char::from(0)).to_owned().into() }; log::info!("Use {} as UI font.", font_family); font_family } } #[inline] fn get_render_target_property( pixel_format: DXGI_FORMAT, alpha_mode: D2D1_ALPHA_MODE, ) -> D2D1_RENDER_TARGET_PROPERTIES { D2D1_RENDER_TARGET_PROPERTIES { r#type: D2D1_RENDER_TARGET_TYPE_DEFAULT, pixelFormat: D2D1_PIXEL_FORMAT { format: pixel_format, alphaMode: alpha_mode, }, dpiX: 96.0, dpiY: 96.0, usage: D2D1_RENDER_TARGET_USAGE_NONE, minLevel: D2D1_FEATURE_LEVEL_DEFAULT, } } // One would think that with newer DirectWrite method: IDWriteFontFace4::GetGlyphImageFormats // but that doesn't seem to work for some glyphs, say ❤ fn is_color_glyph( font_face: &IDWriteFontFace3, glyph_id: GlyphId, factory: &IDWriteFactory5, ) -> bool { let glyph_run = DWRITE_GLYPH_RUN { fontFace: unsafe { std::mem::transmute_copy(font_face) }, fontEmSize: 14.0, glyphCount: 1, glyphIndices: &(glyph_id.0 as u16), glyphAdvances: &0.0, glyphOffsets: &DWRITE_GLYPH_OFFSET { advanceOffset: 0.0, ascenderOffset: 0.0, }, isSideways: BOOL(0), bidiLevel: 0, }; unsafe { factory.TranslateColorGlyphRun( Vector2::default(), &glyph_run as _, None, DWRITE_GLYPH_IMAGE_FORMATS_COLR | DWRITE_GLYPH_IMAGE_FORMATS_SVG | DWRITE_GLYPH_IMAGE_FORMATS_PNG | DWRITE_GLYPH_IMAGE_FORMATS_JPEG | DWRITE_GLYPH_IMAGE_FORMATS_PREMULTIPLIED_B8G8R8A8, DWRITE_MEASURING_MODE_NATURAL, None, 0, ) } .is_ok() } const DEFAULT_LOCALE_NAME: PCWSTR = windows::core::w!("en-US"); const BRUSH_COLOR: D2D1_COLOR_F = D2D1_COLOR_F { r: 1.0, g: 1.0, b: 1.0, a: 1.0, };