Use typed coordinates.

We use Size2D and Point2D across compositing, constellation and script,
losing the type of pixels we use (DevicePixel, DeviceIndepententPixel
or CSSPixel) along the way, which might lead to bugs like
window.outerHeight not taking into account the page zoom (using
DeviceIndepententPixel instead of CSSPixel).

components/compositing/compositor.rs

@@ -6,7 +6,7 @@ use CompositionPipeline;
 use SendableFrameTree;
 use compositor_thread::{CompositorProxy, CompositorReceiver};
 use compositor_thread::{InitialCompositorState, Msg};
-use euclid::{TypedPoint2D, TypedVector2D, TypedScale};
+use euclid::{Length, TypedPoint2D, TypedVector2D, TypedScale};
 use gfx_traits::Epoch;
 use gleam::gl;
 use image::{DynamicImage, ImageFormat, RgbImage};
@@ -274,15 +274,15 @@ impl RenderTargetInfo {
     }
 }
 
-fn initialize_png(gl: &gl::Gl, width: usize, height: usize) -> RenderTargetInfo {
+fn initialize_png(gl: &gl::Gl, width: Length<u32, DevicePixel>, height: Length<u32, DevicePixel>) -> RenderTargetInfo {
     let framebuffer_ids = gl.gen_framebuffers(1);
     gl.bind_framebuffer(gl::FRAMEBUFFER, framebuffer_ids[0]);
 
     let texture_ids = gl.gen_textures(1);
     gl.bind_texture(gl::TEXTURE_2D, texture_ids[0]);
 
-    gl.tex_image_2d(gl::TEXTURE_2D, 0, gl::RGB as gl::GLint, width as gl::GLsizei,
+    gl.tex_image_2d(gl::TEXTURE_2D, 0, gl::RGB as gl::GLint, width.get() as gl::GLsizei,
-                    height as gl::GLsizei, 0, gl::RGB, gl::UNSIGNED_BYTE, None);
+                    height.get() as gl::GLsizei, 0, gl::RGB, gl::UNSIGNED_BYTE, None);
     gl.tex_parameter_i(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::NEAREST as gl::GLint);
     gl.tex_parameter_i(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::NEAREST as gl::GLint);
 
@@ -296,8 +296,8 @@ fn initialize_png(gl: &gl::Gl, width: usize, height: usize) -> RenderTargetInfo
     gl.bind_renderbuffer(gl::RENDERBUFFER, depth_rb);
     gl.renderbuffer_storage(gl::RENDERBUFFER,
                             gl::DEPTH_COMPONENT24,
-                            width as gl::GLsizei,
+                            width.get() as gl::GLsizei,
-                            height as gl::GLsizei);
+                            height.get() as gl::GLsizei);
     gl.framebuffer_renderbuffer(gl::FRAMEBUFFER,
                                 gl::DEPTH_ATTACHMENT,
                                 gl::RENDERBUFFER,
@@ -646,9 +646,11 @@ impl<Window: WindowMethods> IOCompositor<Window> {
             device_pixel_ratio: dppx,
             initial_viewport: initial_viewport,
         };
+
         let top_level_browsing_context_id = self.root_pipeline.as_ref().map(|pipeline| {
             pipeline.top_level_browsing_context_id
         });
+
         let msg = ConstellationMsg::WindowSize(top_level_browsing_context_id, data, size_type);
 
         if let Err(e) = self.constellation_chan.send(msg) {
@@ -1253,8 +1255,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
     fn composite_specific_target(&mut self,
                                  target: CompositeTarget)
                                  -> Result<Option<Image>, UnableToComposite> {
-        let (width, height) =
+        let (width, height) = (self.frame_size.width_typed(), self.frame_size.height_typed());
-            (self.frame_size.width as usize, self.frame_size.height as usize);
         if !self.window.prepare_for_composite(width, height) {
             return Err(UnableToComposite::WindowUnprepared)
         }
@@ -1374,9 +1375,11 @@ impl<Window: WindowMethods> IOCompositor<Window> {
 
     fn draw_img(&self,
                 render_target_info: RenderTargetInfo,
-                width: usize,
+                width: Length<u32, DevicePixel>,
-                height: usize)
+                height: Length<u32, DevicePixel>)
                 -> RgbImage {
+        let width = width.get() as usize;
+        let height = height.get() as usize;
         // For some reason, OSMesa fails to render on the 3rd
         // attempt in headless mode, under some conditions.
         // I think this can only be some kind of synchronization

components/compositing/compositor_thread.rs

@@ -6,7 +6,7 @@
 
 use SendableFrameTree;
 use compositor::CompositingReason;
-use euclid::{Point2D, Size2D};
+use euclid::{TypedPoint2D, TypedSize2D};
 use gfx_traits::Epoch;
 use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::{Key, KeyModifiers, KeyState, PipelineId, TopLevelBrowsingContextId};
@@ -17,6 +17,7 @@ use script_traits::{AnimationState, ConstellationMsg, EventResult, LoadData};
 use servo_url::ServoUrl;
 use std::fmt::{Debug, Error, Formatter};
 use std::sync::mpsc::{Receiver, Sender};
+use style_traits::DevicePixel;
 use style_traits::cursor::CursorKind;
 use style_traits::viewport::ViewportConstraints;
 use webrender;
@@ -119,15 +120,16 @@ pub enum EmbedderMsg {
     /// Alerts the embedder that the current page has changed its title.
     ChangePageTitle(TopLevelBrowsingContextId, Option<String>),
     /// Move the window to a point
-    MoveTo(TopLevelBrowsingContextId, Point2D<i32>),
+    MoveTo(TopLevelBrowsingContextId, TypedPoint2D<i32, DevicePixel>),
     /// Resize the window to size
-    ResizeTo(TopLevelBrowsingContextId, Size2D<u32>),
+    ResizeTo(TopLevelBrowsingContextId, TypedSize2D<u32, DevicePixel>),
     /// Get Window Informations size and position
-    GetClientWindow(TopLevelBrowsingContextId, IpcSender<(Size2D<u32>, Point2D<i32>)>),
+    GetClientWindow(TopLevelBrowsingContextId,
+                    IpcSender<(TypedSize2D<u32, DevicePixel>, TypedPoint2D<i32, DevicePixel>)>),
     /// Get screen size (pixel)
-    GetScreenSize(TopLevelBrowsingContextId, IpcSender<(Size2D<u32>)>),
+    GetScreenSize(TopLevelBrowsingContextId, IpcSender<(TypedSize2D<u32, DevicePixel>)>),
     /// Get screen available size (pixel)
-    GetScreenAvailSize(TopLevelBrowsingContextId, IpcSender<(Size2D<u32>)>),
+    GetScreenAvailSize(TopLevelBrowsingContextId, IpcSender<(TypedSize2D<u32, DevicePixel>)>),
     /// Wether or not to follow a link
     AllowNavigation(TopLevelBrowsingContextId, ServoUrl, IpcSender<bool>),
     /// Sends an unconsumed key event back to the embedder.

components/compositing/windowing.rs

@@ -5,8 +5,7 @@
 //! Abstract windowing methods. The concrete implementations of these can be found in `platform/`.
 
 use compositor_thread::EventLoopWaker;
-use euclid::{Point2D, Size2D};
+use euclid::{Length, TypedScale, TypedPoint2D, TypedSize2D};
-use euclid::{TypedScale, TypedPoint2D, TypedSize2D};
 use gleam::gl;
 use ipc_channel::ipc::IpcSender;
 use msg::constellation_msg::{Key, KeyModifiers, KeyState, TopLevelBrowsingContextId, TraversalDirection};
@@ -123,21 +122,22 @@ pub trait WindowMethods {
     fn framebuffer_size(&self) -> DeviceUintSize;
     /// Returns the position and size of the window within the rendering area.
     fn window_rect(&self) -> DeviceUintRect;
-    /// Returns the size of the window in density-independent "px" units.
+    /// Returns the size of the window.
-    fn size(&self) -> TypedSize2D<f32, DeviceIndependentPixel>;
+    fn size(&self) -> TypedSize2D<f32, DevicePixel>;
     /// Presents the window to the screen (perhaps by page flipping).
     fn present(&self);
 
     /// Return the size of the window with head and borders and position of the window values
-    fn client_window(&self, ctx: TopLevelBrowsingContextId) -> (Size2D<u32>, Point2D<i32>);
+    fn client_window(&self, ctx: TopLevelBrowsingContextId) ->
-    /// Return the size of the screen (pixel)
+        (TypedSize2D<u32, DevicePixel>, TypedPoint2D<i32, DevicePixel>);
-    fn screen_size(&self, ctx: TopLevelBrowsingContextId) -> Size2D<u32>;
+    /// Return the size of the screen.
-    /// Return the available size of the screen (pixel)
+    fn screen_size(&self, ctx: TopLevelBrowsingContextId) -> TypedSize2D<u32, DevicePixel>;
-    fn screen_avail_size(&self, ctx: TopLevelBrowsingContextId) -> Size2D<u32>;
+    /// Return the available size of the screen.
+    fn screen_avail_size(&self, ctx: TopLevelBrowsingContextId) -> TypedSize2D<u32, DevicePixel>;
     /// Set the size inside of borders and head
-    fn set_inner_size(&self, ctx: TopLevelBrowsingContextId, size: Size2D<u32>);
+    fn set_inner_size(&self, ctx: TopLevelBrowsingContextId, size: TypedSize2D<u32, DevicePixel>);
     /// Set the window position
-    fn set_position(&self, ctx: TopLevelBrowsingContextId, point: Point2D<i32>);
+    fn set_position(&self, ctx: TopLevelBrowsingContextId, point: TypedPoint2D<i32, DevicePixel>);
     /// Set fullscreen state
     fn set_fullscreen_state(&self, ctx: TopLevelBrowsingContextId, state: bool);
 
@@ -167,7 +167,7 @@ pub trait WindowMethods {
     /// Requests that the window system prepare a composite. Typically this will involve making
     /// some type of platform-specific graphics context current. Returns true if the composite may
     /// proceed and false if it should not.
-    fn prepare_for_composite(&self, width: usize, height: usize) -> bool;
+    fn prepare_for_composite(&self, width: Length<u32, DevicePixel>, height: Length<u32, DevicePixel>) -> bool;
 
     /// Sets the cursor to be used in the window.
     fn set_cursor(&self, cursor: CursorKind);

components/script/dom/screen.rs

@@ -11,9 +11,10 @@ use dom::bindings::root::{Dom, DomRoot};
 use dom::globalscope::GlobalScope;
 use dom::window::Window;
 use dom_struct::dom_struct;
-use euclid::Size2D;
+use euclid::TypedSize2D;
 use ipc_channel::ipc;
 use script_traits::ScriptMsg;
+use style_traits::{CSSPixel, DevicePixel};
 
 #[dom_struct]
 pub struct Screen {
@@ -35,18 +36,22 @@ impl Screen {
                            ScreenBinding::Wrap)
     }
 
-    fn screen_size(&self) -> Size2D<u32> {
+    fn screen_size(&self) -> TypedSize2D<u32, CSSPixel> {
-        let (send, recv) = ipc::channel::<(Size2D<u32>)>().unwrap();
+        let (send, recv) = ipc::channel::<(TypedSize2D<u32, DevicePixel>)>().unwrap();
         self.window.upcast::<GlobalScope>()
             .script_to_constellation_chan().send(ScriptMsg::GetScreenSize(send)).unwrap();
-        recv.recv().unwrap_or(Size2D::zero())
+        let dpr = self.window.device_pixel_ratio();
+        let screen = recv.recv().unwrap_or(TypedSize2D::zero());
+        (screen.to_f32() / dpr).to_u32()
     }
 
-    fn screen_avail_size(&self) -> Size2D<u32> {
+    fn screen_avail_size(&self) -> TypedSize2D<u32, CSSPixel> {
-        let (send, recv) = ipc::channel::<(Size2D<u32>)>().unwrap();
+        let (send, recv) = ipc::channel::<(TypedSize2D<u32, DevicePixel>)>().unwrap();
         self.window.upcast::<GlobalScope>()
             .script_to_constellation_chan().send(ScriptMsg::GetScreenAvailSize(send)).unwrap();
-        recv.recv().unwrap_or(Size2D::zero())
+        let dpr = self.window.device_pixel_ratio();
+        let screen = recv.recv().unwrap_or(TypedSize2D::zero());
+        (screen.to_f32() / dpr).to_u32()
     }
 }
 

components/script/dom/window.rs

@@ -48,7 +48,7 @@ use dom::windowproxy::WindowProxy;
 use dom::worklet::Worklet;
 use dom::workletglobalscope::WorkletGlobalScopeType;
 use dom_struct::dom_struct;
-use euclid::{Point2D, Vector2D, Rect, Size2D};
+use euclid::{Point2D, Vector2D, Rect, Size2D, TypedPoint2D, TypedScale, TypedSize2D};
 use fetch;
 use ipc_channel::ipc::{self, IpcSender};
 use ipc_channel::router::ROUTER;
@@ -102,7 +102,7 @@ use style::properties::{ComputedValues, PropertyId};
 use style::selector_parser::PseudoElement;
 use style::str::HTML_SPACE_CHARACTERS;
 use style::stylesheets::CssRuleType;
-use style_traits::ParsingMode;
+use style_traits::{CSSPixel, DevicePixel, ParsingMode};
 use task::TaskCanceller;
 use task_source::dom_manipulation::DOMManipulationTaskSource;
 use task_source::file_reading::FileReadingTaskSource;
@@ -930,11 +930,12 @@ impl WindowMethods for Window {
     }
 
     // https://drafts.csswg.org/cssom-view/#dom-window-resizeto
-    fn ResizeTo(&self, x: i32, y: i32) {
+    fn ResizeTo(&self, width: i32, height: i32) {
         // Step 1
         //TODO determine if this operation is allowed
-        let size = Size2D::new(x.to_u32().unwrap_or(1), y.to_u32().unwrap_or(1));
+        let dpr = self.device_pixel_ratio();
-        self.send_to_constellation(ScriptMsg::ResizeTo(size));
+        let size = TypedSize2D::new(width, height).to_f32() * dpr;
+        self.send_to_constellation(ScriptMsg::ResizeTo(size.to_u32()));
     }
 
     // https://drafts.csswg.org/cssom-view/#dom-window-resizeby
@@ -948,8 +949,9 @@ impl WindowMethods for Window {
     fn MoveTo(&self, x: i32, y: i32) {
         // Step 1
         //TODO determine if this operation is allowed
-        let point = Point2D::new(x, y);
+        let dpr = self.device_pixel_ratio();
-        self.send_to_constellation(ScriptMsg::MoveTo(point));
+        let point = TypedPoint2D::new(x, y).to_f32() * dpr;
+        self.send_to_constellation(ScriptMsg::MoveTo(point.to_i32()));
     }
 
     // https://drafts.csswg.org/cssom-view/#dom-window-moveby
@@ -985,8 +987,7 @@ impl WindowMethods for Window {
 
     // https://drafts.csswg.org/cssom-view/#dom-window-devicepixelratio
     fn DevicePixelRatio(&self) -> Finite<f64> {
-        let dpr = self.window_size.get().map_or(1.0f32, |data| data.device_pixel_ratio.get());
+        Finite::wrap(self.device_pixel_ratio().get() as f64)
-        Finite::wrap(dpr as f64)
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-window-status
@@ -1174,10 +1175,16 @@ impl Window {
         self.current_viewport.set(new_viewport)
     }
 
-    pub fn client_window(&self) -> (Size2D<u32>, Point2D<i32>) {
+    pub fn device_pixel_ratio(&self) -> TypedScale<f32, CSSPixel, DevicePixel> {
-        let (send, recv) = ipc::channel::<(Size2D<u32>, Point2D<i32>)>().unwrap();
+        self.window_size.get().map_or(TypedScale::new(1.0), |data| data.device_pixel_ratio)
+    }
+
+    fn client_window(&self) -> (TypedSize2D<u32, CSSPixel>, TypedPoint2D<i32, CSSPixel>) {
+        let (send, recv) = ipc::channel::<(TypedSize2D<u32, DevicePixel>, TypedPoint2D<i32, DevicePixel>)>().unwrap();
         self.send_to_constellation(ScriptMsg::GetClientWindow(send));
-        recv.recv().unwrap_or((Size2D::zero(), Point2D::zero()))
+        let (size, point) = recv.recv().unwrap_or((TypedSize2D::zero(), TypedPoint2D::zero()));
+        let dpr = self.device_pixel_ratio();
+        ((size.to_f32() / dpr).to_u32(), (point.to_f32() / dpr).to_i32())
     }
 
     /// Advances the layout animation clock by `delta` milliseconds, and then

components/script_traits/lib.rs

@@ -41,7 +41,7 @@ pub mod webdriver_msg;
 use bluetooth_traits::BluetoothRequest;
 use canvas_traits::webgl::WebGLPipeline;
 use devtools_traits::{DevtoolScriptControlMsg, ScriptToDevtoolsControlMsg, WorkerId};
-use euclid::{Size2D, Length, Point2D, Vector2D, Rect, TypedScale, TypedSize2D};
+use euclid::{Length, Point2D, Vector2D, Rect, TypedSize2D, TypedScale};
 use gfx_traits::Epoch;
 use hyper::header::Headers;
 use hyper::method::Method;
@@ -650,7 +650,7 @@ pub enum WebDriverCommandMsg {
     /// Act as if keys were pressed in the browsing context with the given ID.
     SendKeys(BrowsingContextId, Vec<(Key, KeyModifiers, KeyState)>),
     /// Set the window size.
-    SetWindowSize(TopLevelBrowsingContextId, Size2D<u32>, IpcSender<WindowSizeData>),
+    SetWindowSize(TopLevelBrowsingContextId, TypedSize2D<u32, DevicePixel>, IpcSender<WindowSizeData>),
     /// Take a screenshot of the window.
     TakeScreenshot(TopLevelBrowsingContextId, IpcSender<Option<Image>>),
 }

components/script_traits/script_msg.rs

@@ -13,7 +13,7 @@ use WorkerGlobalScopeInit;
 use WorkerScriptLoadOrigin;
 use canvas_traits::canvas::CanvasMsg;
 use devtools_traits::{ScriptToDevtoolsControlMsg, WorkerId};
-use euclid::{Point2D, Size2D, TypedSize2D};
+use euclid::{Size2D, TypedPoint2D, TypedSize2D};
 use gfx_traits::Epoch;
 use ipc_channel::ipc::{IpcReceiver, IpcSender};
 use msg::constellation_msg::{BrowsingContextId, PipelineId, TraversalDirection};
@@ -23,7 +23,7 @@ use net_traits::request::RequestInit;
 use net_traits::storage_thread::StorageType;
 use servo_url::ImmutableOrigin;
 use servo_url::ServoUrl;
-use style_traits::CSSPixel;
+use style_traits::{DevicePixel, CSSPixel};
 use style_traits::cursor::CursorKind;
 use style_traits::viewport::ViewportConstraints;
 
@@ -136,11 +136,11 @@ pub enum ScriptMsg {
     /// Send a key event
     SendKeyEvent(Option<char>, Key, KeyState, KeyModifiers),
     /// Get Window Informations size and position
-    GetClientWindow(IpcSender<(Size2D<u32>, Point2D<i32>)>),
+    GetClientWindow(IpcSender<(TypedSize2D<u32, DevicePixel>, TypedPoint2D<i32, DevicePixel>)>),
     /// Move the window to a point
-    MoveTo(Point2D<i32>),
+    MoveTo(TypedPoint2D<i32, DevicePixel>),
     /// Resize the window to size
-    ResizeTo(Size2D<u32>),
+    ResizeTo(TypedSize2D<u32, DevicePixel>),
     /// Script has handled a touch event, and either prevented or allowed default actions.
     TouchEventProcessed(EventResult),
     /// A log entry, with the top-level browsing context id and thread name
@@ -155,9 +155,9 @@ pub enum ScriptMsg {
     /// Enter or exit fullscreen
     SetFullscreenState(bool),
     /// Get the screen size (pixel)
-    GetScreenSize(IpcSender<(Size2D<u32>)>),
+    GetScreenSize(IpcSender<(TypedSize2D<u32, DevicePixel>)>),
     /// Get the available screen size (pixel)
-    GetScreenAvailSize(IpcSender<(Size2D<u32>)>),
+    GetScreenAvailSize(IpcSender<(TypedSize2D<u32, DevicePixel>)>),
     /// Requests that the compositor shut down.
     Exit,
 }

components/servo/lib.rs

@@ -81,6 +81,7 @@ use constellation::{FromCompositorLogger, FromScriptLogger};
 #[cfg(all(not(target_os = "windows"), not(target_os = "ios")))]
 use constellation::content_process_sandbox_profile;
 use env_logger::Logger as EnvLogger;
+use euclid::Length;
 #[cfg(all(not(target_os = "windows"), not(target_os = "ios")))]
 use gaol::sandbox::{ChildSandbox, ChildSandboxMethods};
 use gfx::font_cache_thread::FontCacheThread;
@@ -133,7 +134,7 @@ impl<Window> Servo<Window> where Window: WindowMethods + 'static {
         let opts = opts::get();
 
         // Make sure the gl context is made current.
-        window.prepare_for_composite(0, 0);
+        window.prepare_for_composite(Length::new(0), Length::new(0));
 
         // Get both endpoints of a special channel for communication between
         // the client window and the compositor. This channel is unique because

components/webdriver_server/lib.rs

@@ -27,7 +27,7 @@ extern crate webdriver;
 
 mod keys;
 
-use euclid::Size2D;
+use euclid::TypedSize2D;
 use hyper::method::Method::{self, Post};
 use image::{DynamicImage, ImageFormat, RgbImage};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
@@ -418,7 +418,7 @@ impl Handler {
             Nullable::Value(v) => v,
             Nullable::Null => 0,
         };
-        let size = Size2D::new(width as u32, height as u32);
+        let size = TypedSize2D::new(width as u32, height as u32);
         let top_level_browsing_context_id = self.session()?.top_level_browsing_context_id;
         let cmd_msg = WebDriverCommandMsg::SetWindowSize(top_level_browsing_context_id, size, sender.clone());
 

ports/servo/glutin_app/window.rs

@@ -7,7 +7,7 @@
 use compositing::compositor_thread::EventLoopWaker;
 use compositing::windowing::{AnimationState, MouseWindowEvent, WindowEvent};
 use compositing::windowing::{WebRenderDebugOption, WindowMethods};
-use euclid::{Point2D, Size2D, TypedPoint2D, TypedVector2D, TypedScale, TypedSize2D};
+use euclid::{Length, TypedPoint2D, TypedVector2D, TypedScale, TypedSize2D};
 #[cfg(target_os = "windows")]
 use gdi32;
 use gleam::gl;
@@ -177,18 +177,18 @@ enum WindowKind {
 /// The type of a window.
 pub struct Window {
     kind: WindowKind,
-    screen_size: Size2D<u32>,
+    screen_size: TypedSize2D<u32, DeviceIndependentPixel>,
     inner_size: Cell<TypedSize2D<u32, DeviceIndependentPixel>>,
 
     mouse_down_button: Cell<Option<winit::MouseButton>>,
-    mouse_down_point: Cell<Point2D<i32>>,
+    mouse_down_point: Cell<TypedPoint2D<i32, DeviceIndependentPixel>>,
     event_queue: RefCell<Vec<WindowEvent>>,
 
     /// id of the top level browsing context. It is unique as tabs
     /// are not supported yet. None until created.
     browser_id: Cell<Option<BrowserId>>,
 
-    mouse_pos: Cell<Point2D<i32>>,
+    mouse_pos: Cell<TypedPoint2D<i32, DeviceIndependentPixel>>,
     key_modifiers: Cell<GlutinKeyModifiers>,
     current_url: RefCell<Option<ServoUrl>>,
 
@@ -223,8 +223,7 @@ impl Window {
     pub fn new(is_foreground: bool,
                window_size: TypedSize2D<u32, DeviceIndependentPixel>) -> Rc<Window> {
         let win_size: TypedSize2D<u32, DevicePixel> =
-            (window_size.to_f32() * window_creation_scale_factor())
+            (window_size.to_f32() * window_creation_scale_factor()).to_u32();
-                .to_usize().cast().expect("Window size should fit in u32");
         let width = win_size.to_untyped().width;
         let height = win_size.to_untyped().height;
 
@@ -237,7 +236,7 @@ impl Window {
         let screen_size;
         let inner_size;
         let window_kind = if opts::get().headless {
-            screen_size = Size2D::new(width, height);
+            screen_size = TypedSize2D::new(width, height);
             inner_size = TypedSize2D::new(width, height);
             WindowKind::Headless(HeadlessContext::new(width, height))
         } else {
@@ -268,7 +267,7 @@ impl Window {
             }
 
             let (screen_width, screen_height) = events_loop.get_primary_monitor().get_dimensions();
-            screen_size = Size2D::new(screen_width, screen_height);
+            screen_size = TypedSize2D::new(screen_width, screen_height);
             // TODO(ajeffrey): can this fail?
             let (width, height) = glutin_window.get_inner_size().expect("Failed to get window inner size.");
             inner_size = TypedSize2D::new(width, height);
@@ -316,11 +315,11 @@ impl Window {
             kind: window_kind,
             event_queue: RefCell::new(vec!()),
             mouse_down_button: Cell::new(None),
-            mouse_down_point: Cell::new(Point2D::new(0, 0)),
+            mouse_down_point: Cell::new(TypedPoint2D::new(0, 0)),
 
             browser_id: Cell::new(None),
 
-            mouse_pos: Cell::new(Point2D::new(0, 0)),
+            mouse_pos: Cell::new(TypedPoint2D::new(0, 0)),
             key_modifiers: Cell::new(GlutinKeyModifiers::empty()),
             current_url: RefCell::new(None),
 
@@ -422,8 +421,7 @@ impl Window {
                 }, ..
             } => {
                 if button == MouseButton::Left || button == MouseButton::Right {
-                    let mouse_pos = self.mouse_pos.get();
+                    self.handle_mouse(button, state, self.mouse_pos.get());
-                    self.handle_mouse(button, state, mouse_pos.x, mouse_pos.y);
                 }
             },
             Event::WindowEvent {
@@ -433,7 +431,7 @@ impl Window {
                 },
                 ..
             } => {
-                self.mouse_pos.set(Point2D::new(x as i32, y as i32));
+                self.mouse_pos.set(TypedPoint2D::new(x as i32, y as i32));
                 self.event_queue.borrow_mut().push(
                     WindowEvent::MouseWindowMoveEventClass(TypedPoint2D::new(x as f32, y as f32)));
             }
@@ -481,7 +479,7 @@ impl Window {
                 }
                 // window.set_inner_size() takes DeviceIndependentPixel.
                 let new_size = TypedSize2D::new(width as f32, height as f32);
-                let new_size = (new_size / self.hidpi_factor()).cast().expect("Window size should fit in u32");
+                let new_size = (new_size / self.hidpi_factor()).to_u32();
                 if self.inner_size.get() != new_size {
                     self.inner_size.set(new_size);
                     self.event_queue.borrow_mut().push(WindowEvent::Resize);
@@ -518,37 +516,37 @@ impl Window {
             }
         }
 
-        let mouse_pos = self.mouse_pos.get();
+        let pos = self.mouse_pos.get().to_f32() * self.hidpi_factor();
-        let event = WindowEvent::Scroll(scroll_location,
+        let event = WindowEvent::Scroll(scroll_location, pos.to_i32(), phase);
-                                        TypedPoint2D::new(mouse_pos.x as i32, mouse_pos.y as i32),
-                                        phase);
         self.event_queue.borrow_mut().push(event);
     }
 
     /// Helper function to handle a click
-    fn handle_mouse(&self, button: winit::MouseButton, action: winit::ElementState, x: i32, y: i32) {
+    fn handle_mouse(&self, button: winit::MouseButton,
+                    action: winit::ElementState,
+                    coords: TypedPoint2D<i32, DeviceIndependentPixel>) {
         use script_traits::MouseButton;
 
         // FIXME(tkuehn): max pixel dist should be based on pixel density
         let max_pixel_dist = 10f64;
+        let scaled_coords = coords.to_f32() * self.hidpi_factor();
         let event = match action {
             ElementState::Pressed => {
-                self.mouse_down_point.set(Point2D::new(x, y));
+                self.mouse_down_point.set(coords);
                 self.mouse_down_button.set(Some(button));
-                MouseWindowEvent::MouseDown(MouseButton::Left, TypedPoint2D::new(x as f32, y as f32))
+                MouseWindowEvent::MouseDown(MouseButton::Left, scaled_coords)
             }
             ElementState::Released => {
-                let mouse_up_event = MouseWindowEvent::MouseUp(MouseButton::Left,
+                let mouse_up_event = MouseWindowEvent::MouseUp(MouseButton::Left, scaled_coords);
-                                                               TypedPoint2D::new(x as f32, y as f32));
                 match self.mouse_down_button.get() {
                     None => mouse_up_event,
                     Some(but) if button == but => {
-                        let pixel_dist = self.mouse_down_point.get() - Point2D::new(x, y);
+                        let pixel_dist = self.mouse_down_point.get() - coords;
                         let pixel_dist = ((pixel_dist.x * pixel_dist.x +
                                            pixel_dist.y * pixel_dist.y) as f64).sqrt();
                         if pixel_dist < max_pixel_dist {
                             self.event_queue.borrow_mut().push(WindowEvent::MouseWindowEventClass(mouse_up_event));
-                            MouseWindowEvent::Click(MouseButton::Left, TypedPoint2D::new(x as f32, y as f32))
+                            MouseWindowEvent::Click(MouseButton::Left, scaled_coords)
                         } else {
                             mouse_up_event
                         }
@@ -871,7 +869,7 @@ impl WindowMethods for Window {
     }
 
     fn framebuffer_size(&self) -> DeviceUintSize {
-        (self.inner_size.get().to_f32() * self.hidpi_factor()).to_usize().cast().expect("Window size should fit in u32")
+        self.size().to_u32()
     }
 
     fn window_rect(&self) -> DeviceUintRect {
@@ -880,34 +878,36 @@ impl WindowMethods for Window {
         DeviceUintRect::new(origin, size)
     }
 
-    fn size(&self) -> TypedSize2D<f32, DeviceIndependentPixel> {
+    fn size(&self) -> TypedSize2D<f32, DevicePixel> {
-        self.inner_size.get().to_f32()
+        self.inner_size.get().to_f32() * self.hidpi_factor()
     }
 
-    fn client_window(&self, _: BrowserId) -> (Size2D<u32>, Point2D<i32>) {
+    fn client_window(&self, _: BrowserId) -> (TypedSize2D<u32, DevicePixel>, TypedPoint2D<i32, DevicePixel>) {
-        match self.kind {
+        let (size, point) = match self.kind {
             WindowKind::Window(ref window, ..) => {
                 // TODO(ajeffrey): can this fail?
                 let (width, height) = window.get_outer_size().expect("Failed to get window outer size.");
-                let size = Size2D::new(width, height);
+                let size = TypedSize2D::new(width as f32, height as f32);
                 // TODO(ajeffrey): can this fail?
                 let (x, y) = window.get_position().expect("Failed to get window position.");
-                let origin = Point2D::new(x as i32, y as i32);
+                let origin = TypedPoint2D::new(x as f32, y as f32);
                 (size, origin)
             }
             WindowKind::Headless(ref context) => {
-                let size = TypedSize2D::new(context.width, context.height);
+                let size = TypedSize2D::new(context.width as f32, context.height as f32);
-                (size, Point2D::zero())
+                let origin = TypedPoint2D::zero();
+                (size, origin)
             }
-        }
+        };
-
+        let dpr = self.hidpi_factor();
+        ((size * dpr).to_u32(), (point * dpr).to_i32())
     }
 
-    fn screen_size(&self, _: BrowserId) -> Size2D<u32> {
+    fn screen_size(&self, _: BrowserId) -> TypedSize2D<u32, DevicePixel> {
-        self.screen_size
+        (self.screen_size.to_f32() * self.hidpi_factor()).to_u32()
     }
 
-    fn screen_avail_size(&self, browser_id: BrowserId) -> Size2D<u32> {
+    fn screen_avail_size(&self, browser_id: BrowserId) -> TypedSize2D<u32, DevicePixel> {
         // FIXME: Glutin doesn't have API for available size. Fallback to screen size
         self.screen_size(browser_id)
     }
@@ -916,19 +916,21 @@ impl WindowMethods for Window {
         self.animation_state.set(state);
     }
 
-    fn set_inner_size(&self, _: BrowserId, size: Size2D<u32>) {
+    fn set_inner_size(&self, _: BrowserId, size: TypedSize2D<u32, DevicePixel>) {
         match self.kind {
             WindowKind::Window(ref window, ..) => {
+                let size = size.to_f32() / self.hidpi_factor();
                 window.set_inner_size(size.width as u32, size.height as u32)
             }
             WindowKind::Headless(..) => {}
         }
     }
 
-    fn set_position(&self, _: BrowserId, point: Point2D<i32>) {
+    fn set_position(&self, _: BrowserId, point: TypedPoint2D<i32, DevicePixel>) {
         match self.kind {
             WindowKind::Window(ref window, ..) => {
-                window.set_position(point.x, point.y)
+                let point = point.to_f32() / self.hidpi_factor();
+                window.set_position(point.x as i32, point.y as i32)
             }
             WindowKind::Headless(..) => {}
         }
@@ -1112,7 +1114,7 @@ impl WindowMethods for Window {
     fn set_favicon(&self, _: BrowserId, _: ServoUrl) {
     }
 
-    fn prepare_for_composite(&self, _width: usize, _height: usize) -> bool {
+    fn prepare_for_composite(&self, _width: Length<u32, DevicePixel>, _height: Length<u32, DevicePixel>) -> bool {
         true
     }