Bug 1521450 - Enable per-monitor DPI scaling V2 in the Windows GUI r=gsvelto,glandium

This is quite an improvement on the quirks of the previous GDI scaling.

It also mostly supports the windows 10+ "Make text bigger" setting: it
reads the value from the registry (albeit at an unofficial location),
but doesn't register a key change listener to update the value if it
changes while the application is open. I think this is very, very likely
to be good enough; I will be surprised if someone notices this
deficiency! The official API is part of UWP and is accessible through
C++ libraries, but not conveniently through win32 APIs, which is why I
use the registry.

Differential Revision: https://phabricator.services.mozilla.com/D221544

build/workspace-hack/Cargo.toml

@@ -216,11 +216,13 @@ features = [
     "Win32_System_Memory",
     "Win32_System_Pipes",
     "Win32_System_ProcessStatus",
+    "Win32_System_Registry",
     "Win32_System_SystemInformation",
     "Win32_System_SystemServices",
     "Win32_System_Threading",
     "Win32_System_WindowsProgramming",
     "Win32_UI_Controls",
+    "Win32_UI_HiDpi",
     "Win32_UI_Input_KeyboardAndMouse",
     "Win32_UI_Shell",
     "Win32_UI_WindowsAndMessaging",

toolkit/crashreporter/client/app/Cargo.toml

@@ -47,9 +47,11 @@ features = [
     "Win32_Graphics_Gdi",
     "Win32_System_Com",
     "Win32_System_LibraryLoader",
+    "Win32_System_Registry",
     "Win32_System_SystemServices",
     "Win32_System_Threading",
     "Win32_UI_Controls",
+    "Win32_UI_HiDpi",
     "Win32_UI_Input_KeyboardAndMouse",
     "Win32_UI_Shell",
     "Win32_UI_WindowsAndMessaging"

toolkit/crashreporter/client/app/build.rs

@@ -25,9 +25,9 @@ fn windows_manifest() {
         // Use legacy active code page because GDI doesn't support per-process UTF8 (and older
         // win10 may not support this setting anyway).
         .active_code_page(manifest::ActiveCodePage::Legacy)
-        // GDI scaling is not enabled by default but we need it to make the GDI-drawn text look
-        // nice on high-DPI displays.
-        .gdi_scaling(manifest::Setting::Enabled);
+        // We support WM_DPICHANGED for scaling, but need to set our DPI awareness to receive the
+        // messages.
+        .dpi_awareness(manifest::DpiAwareness::PerMonitorV2);
 
     embed_manifest(manifest).expect("unable to embed windows manifest file");
 

toolkit/crashreporter/client/app/src/data.rs

@@ -135,6 +135,15 @@ impl<T> Synchronized<T> {
         });
     }
 
+    /// Immediately call the closure on the current value and call it whenever the value changes.
+    pub fn map_with<F: Fn(&T) + 'static>(&self, f: F) {
+        // Hold the borrow to guarantee the value doesn't change until we are subscribed (just as a
+        // measure of extra sanity; this should never occur).
+        let borrow = self.borrow();
+        f(&*borrow);
+        self.on_change(f);
+    }
+
     /// Create a new synchronized value which will update when this one changes.
     pub fn mapped<U: 'static, F: Fn(&T) -> U + 'static>(&self, f: F) -> Synchronized<U> {
         let s = Synchronized::new(f(&*self.borrow()));

toolkit/crashreporter/client/app/src/ui/windows/dpi.rs

@@ -0,0 +1,63 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//! DPI management utilities.
+
+use windows_sys::Win32::{
+    Foundation::HWND,
+    UI::{HiDpi::GetDpiForWindow, WindowsAndMessaging::USER_DEFAULT_SCREEN_DPI as DEFAULT_DPI},
+};
+
+// To simplify layout code (avoiding passing values through many functions), we provide an API
+// which can set a contextual Dpi.
+thread_local! {
+    static CONTEXT_DPI: std::cell::Cell<Dpi> = Dpi::default().into();
+}
+
+/// A DPI value.
+#[derive(Clone, Copy, Debug)]
+pub struct Dpi(u32);
+
+impl Default for Dpi {
+    fn default() -> Self {
+        Dpi(DEFAULT_DPI)
+    }
+}
+
+impl Dpi {
+    /// Create a new Dpi.
+    pub fn new(dpi: u32) -> Self {
+        Dpi(dpi)
+    }
+
+    /// Get the Dpi for the given window.
+    pub fn for_window(hwnd: HWND) -> Self {
+        Dpi(unsafe { GetDpiForWindow(hwnd) })
+    }
+
+    /// Scale a pixel value according to this Dpi.
+    pub fn scale(&self, value: u32) -> u32 {
+        if self.0 == DEFAULT_DPI {
+            value
+        } else {
+            (value as u64 * self.0 as u64 / DEFAULT_DPI as u64) as u32
+        }
+    }
+
+    /// Call the given capture with this Dpi set as the contextual Dpi.
+    pub fn with_context<F, R>(&self, f: F) -> R
+    where
+        F: FnOnce() -> R,
+    {
+        let old = CONTEXT_DPI.replace(*self);
+        let ret = f();
+        CONTEXT_DPI.set(old);
+        ret
+    }
+
+    /// Scale a pixel value according to the contextual Dpi.
+    pub fn context_scale(value: u32) -> u32 {
+        CONTEXT_DPI.get().scale(value)
+    }
+}

toolkit/crashreporter/client/app/src/ui/windows/font.rs

@@ -2,21 +2,101 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use windows_sys::Win32::{Foundation::S_OK, Graphics::Gdi, UI::Controls};
+use super::Dpi;
+use super::WideString;
+use windows_sys::Win32::{
+    Foundation::{ERROR_SUCCESS, S_OK},
+    Graphics::Gdi,
+    System::Registry,
+    UI::Controls,
+};
 
-/// Windows font handle (`HFONT`).
-pub struct Font(Gdi::HFONT);
+/// The default font size to use.
+///
+/// `GetThemeSysFont` scales the font based on DPI and accessibility settings, however it only takes
+/// those active at application startup into account (it won't scale correctly across monitors, nor
+/// if the DPI of the current monitor changes). So we use a fixed size instead and scale that.
+const DEFAULT_FONT_SIZE: i32 = -12;
 
-impl Font {
+/// The set of fonts to use.
+pub struct Fonts {
+    pub normal: Font,
+    pub bold: Font,
+}
+
+/// The scale factor set by the windows 10 "make text bigger" accessibility setting.
+#[derive(Clone, Copy, Debug)]
+pub struct ScaleFactor(f32);
+
+impl ScaleFactor {
+    /// Create a new scale factor.
+    ///
+    /// The factor will be clamped to [1,2.25], to match the
+    /// [documentation](https://learn.microsoft.com/en-us/uwp/api/windows.ui.viewmanagement.uisettings.textscalefactor)
+    /// and avoid any surprises.
+    pub fn new(factor: f32) -> Self {
+        ScaleFactor(factor.clamp(1., 2.25))
+    }
+
+    /// Get the current scale factor setting from the registry.
+    pub fn from_registry() -> Self {
+        let key = WideString::new("SOFTWARE\\Microsoft\\Accessibility");
+        let value = WideString::new("TextScaleFactor");
+        let mut scale_factor: [u8; 4] = Default::default();
+        let mut size: u32 = std::mem::size_of_val(&scale_factor) as u32;
+        let mut reg_type: u32 = 0;
+        let result = unsafe {
+            Registry::RegGetValueW(
+                Registry::HKEY_CURRENT_USER,
+                key.pcwstr(),
+                value.pcwstr(),
+                Registry::RRF_RT_REG_DWORD,
+                &mut reg_type,
+                &mut scale_factor as *mut u8 as _,
+                &mut size,
+            )
+        };
+        let percent = if result == ERROR_SUCCESS {
+            if reg_type == Registry::REG_DWORD_BIG_ENDIAN {
+                u32::from_be_bytes(scale_factor)
+            } else {
+                u32::from_le_bytes(scale_factor)
+            }
+        } else {
+            100
+        };
+        Self::new(percent as f32 / 100.)
+    }
+}
+
+impl Fonts {
+    pub fn new(dpi: Dpi, scale_factor: ScaleFactor) -> Self {
+        let builder = FontBuilder { dpi, scale_factor };
+        Fonts {
+            normal: builder.caption(),
+            bold: builder.caption_bold().unwrap_or_else(|| builder.caption()),
+        }
+    }
+}
+
+pub struct FontBuilder {
+    dpi: Dpi,
+    scale_factor: ScaleFactor,
+}
+
+impl FontBuilder {
     /// Get the system theme caption font.
     ///
     /// Panics if the font cannot be retrieved.
-    pub fn caption() -> Self {
+    pub fn caption(&self) -> Font {
         unsafe {
             let mut font = std::mem::zeroed::<Gdi::LOGFONTW>();
             success!(hresult
                 Controls::GetThemeSysFont(0, Controls::TMT_CAPTIONFONT as i32, &mut font)
             );
+            font.lfHeight = DEFAULT_FONT_SIZE;
+            self.scale_font_height(&mut font.lfHeight);
+            font.lfWidth = 0;
             Font(success!(pointer Gdi::CreateFontIndirectW(&font)))
         }
     }
@@ -24,12 +104,15 @@ impl Font {
     /// Get the system theme bold caption font.
     ///
     /// Returns `None` if the font cannot be retrieved.
-    pub fn caption_bold() -> Option<Self> {
+    pub fn caption_bold(&self) -> Option<Font> {
         unsafe {
             let mut font = std::mem::zeroed::<Gdi::LOGFONTW>();
             if Controls::GetThemeSysFont(0, Controls::TMT_CAPTIONFONT as i32, &mut font) != S_OK {
                 return None;
             }
+            font.lfHeight = DEFAULT_FONT_SIZE;
+            self.scale_font_height(&mut font.lfHeight);
+            font.lfWidth = 0;
             font.lfWeight = Gdi::FW_BOLD as i32;
 
             let ptr = Gdi::CreateFontIndirectW(&font);
@@ -39,8 +122,16 @@ impl Font {
             Some(Font(ptr))
         }
     }
+
+    fn scale_font_height(&self, height: &mut i32) {
+        *height = (self.dpi.scale(height.abs() as u32) as f32 * self.scale_factor.0) as i32
+            * if height.is_negative() { -1 } else { 1 };
+    }
 }
 
+/// Windows font handle (`HFONT`).
+pub struct Font(Gdi::HFONT);
+
 impl std::ops::Deref for Font {
     type Target = Gdi::HFONT;
 

toolkit/crashreporter/client/app/src/ui/windows/layout.rs

@@ -6,7 +6,7 @@
 
 use super::{
     model::{self, Alignment, Element, ElementStyle, Margin},
-    ElementRef, WideString,
+    Dpi, ElementRef, WideString,
 };
 use crate::data::Property;
 use std::collections::HashMap;
@@ -29,6 +29,7 @@ pub(super) type ElementMapping = HashMap<ElementRef, HWND>;
 /// disparate locations.
 pub struct Layout<'a> {
     elements: &'a ElementMapping,
+    dpi: Dpi,
     sizes: HashMap<ElementRef, Size>,
     last_positioned: Option<HWND>,
 }
@@ -49,9 +50,10 @@ const CHECKBOX_MARGIN: Margin = Margin {
 };
 
 impl<'a> Layout<'a> {
-    pub(super) fn new(elements: &'a ElementMapping) -> Self {
+    pub(super) fn new(elements: &'a ElementMapping, dpi: Dpi) -> Self {
         Layout {
             elements,
+            dpi,
             sizes: Default::default(),
             last_positioned: None,
         }
@@ -59,12 +61,14 @@ impl<'a> Layout<'a> {
 
     /// Perform a layout of the element and all child elements.
     pub fn layout(mut self, element: &Element, max_width: u32, max_height: u32) {
-        let max_size = Size {
-            width: max_width,
-            height: max_height,
-        };
-        self.resize(element, &max_size);
-        self.reposition(element, &Position::default(), &max_size);
+        self.dpi.clone().with_context(|| {
+            let max_size = Size {
+                width: max_width,
+                height: max_height,
+            };
+            self.resize(element, &max_size);
+            self.reposition(element, &Position::default(), &max_size);
+        })
     }
 
     fn resize(&mut self, element: &Element, max_size: &Size) -> Size {
@@ -126,6 +130,7 @@ impl<'a> Layout<'a> {
                 content_size = Some(size);
             }
             VBox(model::VBox { items, spacing }) => {
+                let spacing = Dpi::context_scale(*spacing);
                 let mut height = 0;
                 let mut max_width = 0;
                 let mut remaining_size = inner_size.clone();
@@ -160,6 +165,7 @@ impl<'a> Layout<'a> {
                 spacing,
                 affirmative_order: _,
             }) => {
+                let spacing = Dpi::context_scale(*spacing);
                 let mut width = 0;
                 let mut max_height = 0;
                 let mut remaining_size = inner_size.clone();
@@ -197,8 +203,8 @@ impl<'a> Layout<'a> {
             Progress(model::Progress { .. }) => {
                 // Min size recommended by windows uxguide
                 content_size = Some(Size {
-                    width: 160,
-                    height: 15,
+                    width: Dpi::context_scale(160),
+                    height: Dpi::context_scale(15),
                 });
             }
             // We don't support sizing by textbox content yet (need to read from the HWND due to
@@ -273,7 +279,7 @@ impl<'a> Layout<'a> {
                 let mut size = inner_size;
                 for item in items {
                     self.reposition(item, &position, &size);
-                    let consumed = self.get_size(item).height + spacing;
+                    let consumed = self.get_size(item).height + Dpi::context_scale(*spacing);
                     if item.style.vertical_alignment != Alignment::End {
                         position.top += consumed;
                     }
@@ -290,7 +296,7 @@ impl<'a> Layout<'a> {
                 let mut size = inner_size;
                 for item in items {
                     self.reposition(item, &position, &inner_size);
-                    let consumed = self.get_size(item).width + spacing;
+                    let consumed = self.get_size(item).width + Dpi::context_scale(*spacing);
                     if item.style.horizontal_alignment != Alignment::End {
                         position.start += consumed;
                     }
@@ -377,21 +383,21 @@ impl Size {
     pub fn inner_size(&self, style: &ElementStyle) -> Self {
         let mut ret = self.less_margin(&style.margin);
         if let Some(width) = style.horizontal_size_request {
-            ret.width = width;
+            ret.width = Dpi::context_scale(width);
         }
         if let Some(height) = style.vertical_size_request {
-            ret.height = height;
+            ret.height = Dpi::context_scale(height);
         }
         ret
     }
 
     pub fn from_content_size(&mut self, style: &ElementStyle, content_size: &Self) {
-        if style.horizontal_size_request < Some(content_size.width)
+        if style.horizontal_size_request.map(Dpi::context_scale) < Some(content_size.width)
             && style.horizontal_alignment != Alignment::Fill
         {
             self.width = content_size.width;
         }
-        if style.vertical_size_request < Some(content_size.height)
+        if style.vertical_size_request.map(Dpi::context_scale) < Some(content_size.height)
             && style.vertical_alignment != Alignment::Fill
         {
             self.height = content_size.height;
@@ -400,15 +406,19 @@ impl Size {
 
     pub fn plus_margin(&self, margin: &Margin) -> Self {
         let mut ret = self.clone();
-        ret.width += margin.start + margin.end;
-        ret.height += margin.top + margin.bottom;
+        ret.width += Dpi::context_scale(margin.start + margin.end);
+        ret.height += Dpi::context_scale(margin.top + margin.bottom);
         ret
     }
 
     pub fn less_margin(&self, margin: &Margin) -> Self {
         let mut ret = self.clone();
-        ret.width = ret.width.saturating_sub(margin.start + margin.end);
-        ret.height = ret.height.saturating_sub(margin.top + margin.bottom);
+        ret.width = ret
+            .width
+            .saturating_sub(Dpi::context_scale(margin.start + margin.end));
+        ret.height = ret
+            .height
+            .saturating_sub(Dpi::context_scale(margin.top + margin.bottom));
         ret
     }
 }
@@ -423,15 +433,15 @@ impl Position {
     #[allow(dead_code)]
     pub fn plus_margin(&self, margin: &Margin) -> Self {
         let mut ret = self.clone();
-        ret.start = ret.start.saturating_sub(margin.start);
-        ret.top = ret.top.saturating_sub(margin.top);
+        ret.start = ret.start.saturating_sub(Dpi::context_scale(margin.start));
+        ret.top = ret.top.saturating_sub(Dpi::context_scale(margin.top));
         ret
     }
 
     pub fn less_margin(&self, margin: &Margin) -> Self {
         let mut ret = self.clone();
-        ret.start += margin.start;
-        ret.top += margin.top;
+        ret.start += Dpi::context_scale(margin.start);
+        ret.top += Dpi::context_scale(margin.top);
         ret
     }
 }

toolkit/crashreporter/client/app/src/ui/windows/mod.rs

@@ -22,8 +22,9 @@
 extern "C" {}
 
 use super::model::{self, Application, Element, ElementStyle, TypedElement};
-use crate::data::Property;
-use font::Font;
+use crate::data::{Property, Synchronized};
+use dpi::Dpi;
+use font::Fonts;
 use once_cell::sync::Lazy;
 use quit_token::QuitToken;
 use std::cell::RefCell;
@@ -61,6 +62,7 @@ macro_rules! success {
     }};
 }
 
+mod dpi;
 mod font;
 mod gdi;
 mod layout;
@@ -318,6 +320,8 @@ impl CustomWindowClass for AppWindow {
         let model = me.renderer.model();
         match umsg {
             win::WM_CREATE => {
+                me.renderer.set_dpi(Dpi::for_window(hwnd));
+
                 if let Some(close) = &model.close {
                     close.subscribe(move |&()| unsafe {
                         win::SendMessageW(hwnd, win::WM_CLOSE, 0, 0);
@@ -358,8 +362,8 @@ impl CustomWindowClass for AppWindow {
             }
             win::WM_GETMINMAXINFO => {
                 let minmaxinfo = unsafe { (lparam as *mut win::MINMAXINFO).as_mut().unwrap() };
-                minmaxinfo.ptMinTrackSize.x = me.renderer.min_size.0.try_into().unwrap();
-                minmaxinfo.ptMinTrackSize.y = me.renderer.min_size.1.try_into().unwrap();
+                minmaxinfo.ptMinTrackSize.x = me.renderer.min_width().try_into().unwrap();
+                minmaxinfo.ptMinTrackSize.y = me.renderer.min_height().try_into().unwrap();
                 return Some(0);
             }
             win::WM_SIZE => {
@@ -373,7 +377,31 @@ impl CustomWindowClass for AppWindow {
                 }
                 return Some(0);
             }
-            win::WM_GETFONT => return Some(**me.renderer.font() as _),
+            win::WM_DPICHANGED => {
+                // When DPI changes, recompute the layout and move the window.
+                let rect: &RECT = unsafe { (lparam as *const RECT).as_ref() }
+                    .expect("null RECT pointer in WM_DPICHANGED");
+                let dpi = loword(wparam as _) as u32;
+
+                let width = rect.right - rect.left;
+                let height = rect.bottom - rect.top;
+
+                me.renderer.set_dpi(Dpi::new(dpi));
+                // This wil send WM_SIZE, which will take care of the new layout.
+                unsafe {
+                    win::SetWindowPos(
+                        hwnd,
+                        win::HWND_TOP,
+                        rect.left,
+                        rect.top,
+                        width,
+                        height,
+                        win::SWP_NOZORDER | win::SWP_NOACTIVATE,
+                    )
+                };
+                return Some(0);
+            }
+            win::WM_GETFONT => return Some(me.renderer.font()),
             win::WM_COMMAND => {
                 let child = lparam as HWND;
                 let windows = me.renderer.windows.borrow();
@@ -435,17 +463,20 @@ struct WindowRendererInner {
     /// changes. Unfortunately the win32 API doesn't have any nice ways to automatically perform
     /// layout.
     pub model: RefCell<Pin<Box<model::Window>>>,
-    pub min_size: (u32, u32),
+    min_size: (u32, u32),
     /// Mapping between model elements and windows.
     ///
     /// Element references pertain to elements in `model`.
     pub windows: RefCell<twoway::TwoWay<ElementRef, HWND>>,
-    pub font: Font,
-    pub bold_font: Font,
+    pub dpi: Synchronized<Dpi>,
+    pub fonts: Synchronized<Fonts>,
 }
 
 impl WindowRenderer {
     pub fn new(module: HINSTANCE, model: model::Window, style: &model::ElementStyle) -> Self {
+        let dpi: Synchronized<Dpi> = Default::default();
+        let scale_factor = font::ScaleFactor::from_registry();
+        let fonts = dpi.mapped(move |dpi| Fonts::new(*dpi, scale_factor));
         WindowRenderer {
             inner: Rc::new(WindowRendererInner {
                 module,
@@ -455,8 +486,8 @@ impl WindowRenderer {
                     style.vertical_size_request.unwrap_or(0),
                 ),
                 windows: Default::default(),
-                font: Font::caption(),
-                bold_font: Font::caption_bold().unwrap_or_else(Font::caption),
+                dpi,
+                fonts,
             }),
         }
     }
@@ -470,9 +501,16 @@ impl WindowRenderer {
         }
     }
 
+    pub fn set_dpi(&self, dpi: Dpi) {
+        *self.dpi.borrow_mut() = dpi;
+    }
+
     pub fn layout(&self, element: &Element, max_width: u32, max_height: u32) {
-        layout::Layout::new(self.inner.windows.borrow().forward())
-            .layout(element, max_width, max_height);
+        layout::Layout::new(
+            self.inner.windows.borrow().forward(),
+            *self.inner.dpi.borrow(),
+        )
+        .layout(element, max_width, max_height);
     }
 
     pub fn model(&self) -> std::cell::Ref<'_, model::Window> {
@@ -483,8 +521,16 @@ impl WindowRenderer {
         std::cell::RefMut::map(self.inner.model.borrow_mut(), |b| &mut **b)
     }
 
-    pub fn font(&self) -> &Font {
-        &self.inner.font
+    pub fn font(&self) -> Gdi::HFONT {
+        *self.inner.fonts.borrow().normal
+    }
+
+    pub fn min_width(&self) -> u32 {
+        self.inner.dpi.borrow().scale(self.min_size.0)
+    }
+
+    pub fn min_height(&self) -> u32 {
+        self.inner.dpi.borrow().scale(self.min_size.1)
     }
 }
 
@@ -558,7 +604,7 @@ impl<'a> WindowChildRenderer<'a> {
 
     fn render_child(&mut self, element: &Element) {
         if let Some(mut window) = self.render_element_type(&element.element_type) {
-            window.set_default_font(&self.renderer.font);
+            window.set_default_font(&self.renderer.fonts, |fonts| &fonts.normal);
 
             // Store the element to handle mapping.
             self.renderer
@@ -641,7 +687,7 @@ impl<'a> WindowChildRenderer<'a> {
                     }
                 };
                 if *bold {
-                    window.set_font(&self.renderer.bold_font);
+                    window.set_font(&self.renderer.fonts, |fonts| &fonts.bold);
                 }
                 Some(window.generic())
             }

toolkit/crashreporter/client/app/src/ui/windows/window.rs

@@ -4,8 +4,9 @@
 
 //! Types and helpers relating to windows and window classes.
 
-use super::Font;
+use super::font::{Font, Fonts};
 use super::WideString;
+use crate::data::Synchronized;
 use std::cell::RefCell;
 use windows_sys::Win32::{
     Foundation::{HINSTANCE, HWND, LPARAM, LRESULT, WPARAM},
@@ -297,15 +298,26 @@ impl<W> Window<W> {
     }
 
     /// Set a window's font.
-    pub fn set_font(&mut self, font: &Font) {
-        unsafe { win::SendMessageW(self.handle, win::WM_SETFONT, **font as _, 1 as _) };
+    pub fn set_font(
+        &mut self,
+        fonts: &Synchronized<Fonts>,
+        font: impl Fn(&Fonts) -> &Font + 'static,
+    ) {
+        let handle = self.handle;
+        fonts.map_with(move |fonts| unsafe {
+            win::SendMessageW(handle, win::WM_SETFONT, **font(fonts) as _, 1 as _);
+        });
         self.font_set = true;
     }
 
     /// Set a window's font if not already set.
-    pub fn set_default_font(&mut self, font: &Font) {
+    pub fn set_default_font(
+        &mut self,
+        fonts: &Synchronized<Fonts>,
+        font: impl Fn(&Fonts) -> &Font + 'static,
+    ) {
         if !self.font_set {
-            self.set_font(font);
+            self.set_font(fonts, font);
         }
     }
 }