3 files changed, 22 insertions, 7 deletions
diff --git a/components/compositing/compositor.rs b/components/compositing/compositor.rs
index dcff6ef66fe..c440796453b 100644
--- a/components/compositing/compositor.rs
+++ b/components/compositing/compositor.rs
@@ -32,7 +32,7 @@ use script_traits::{
     MouseButton, MouseEventType, ScrollState, TouchEventType, TouchId, WheelDelta,
 };
 use script_traits::{UntrustedNodeAddress, WindowSizeData, WindowSizeType};
-use servo_geometry::DeviceIndependentPixel;
+use servo_geometry::{DeviceIndependentPixel, FramebufferUintLength};
 use std::collections::HashMap;
 use std::env;
 use std::fs::{create_dir_all, File};
@@ -1268,7 +1268,9 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             CompositeTarget::Window => gl::RenderTargetInfo::default(),
             #[cfg(feature = "gl")]
             CompositeTarget::WindowAndPng | CompositeTarget::PngFile => {
-                gl::initialize_png(&*self.window.gl(), width, height)
+                gl::initialize_png(&*self.window.gl(),
+                                   FramebufferUintLength::new(width.get()),
+                                   FramebufferUintLength::new(height.get()))
             },
             #[cfg(not(feature = "gl"))]
             _ => (),
@@ -1330,7 +1332,10 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             CompositeTarget::Window => None,
             #[cfg(feature = "gl")]
             CompositeTarget::WindowAndPng => {
-                let img = gl::draw_img(&*self.window.gl(), rt_info, width, height);
+                let img = gl::draw_img(&*self.window.gl(),
+                                       rt_info,
+                                       FramebufferUintLength::new(width.get()),
+                                       FramebufferUintLength::new(height.get()));
                 Some(Image {
                     width: img.width(),
                     height: img.height(),
@@ -1349,7 +1354,10 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
                     || match self.output_file.as_ref() {
                         Some(path) => match File::create(path) {
                             Ok(mut file) => {
-                                let img = gl::draw_img(gl, rt_info, width, height);
+                                let img = gl::draw_img(gl,
+                                                       rt_info,
+                                                       FramebufferUintLength::new(width.get()),
+                                                       FramebufferUintLength::new(height.get()));
                                 let dynamic_image = DynamicImage::ImageRgb8(img);
                                 if let Err(e) = dynamic_image.write_to(&mut file, ImageFormat::PNG)
                                 {
diff --git a/components/compositing/windowing.rs b/components/compositing/windowing.rs
index aa0bdc21384..90ced19bc09 100644
--- a/components/compositing/windowing.rs
+++ b/components/compositing/windowing.rs
@@ -21,7 +21,7 @@ use std::time::Duration;
 use style_traits::DevicePixel;
 use webrender_api::ScrollLocation;
 use webrender_api::units::{DeviceIntPoint, DeviceIntRect, DeviceIntSize};
-use webrender_api::units::{DevicePoint, FramebufferIntSize};
+use webrender_api::units::DevicePoint;
 use webvr::VRServiceManager;
 use webvr_traits::WebVRMainThreadHeartbeat;
 
@@ -191,7 +191,7 @@ pub struct EmbedderCoordinates {
     /// Size of the native window.
     pub window: (DeviceIntSize, DeviceIntPoint),
     /// Size of the GL buffer in the window.
-    pub framebuffer: FramebufferIntSize,
+    pub framebuffer: DeviceIntSize,
     /// Coordinates of the document within the framebuffer.
     pub viewport: DeviceIntRect,
 }
diff --git a/components/servo/lib.rs b/components/servo/lib.rs
index b75433bb213..feb31036fdc 100644
--- a/components/servo/lib.rs
+++ b/components/servo/lib.rs
@@ -84,6 +84,7 @@ use constellation::{FromCompositorLogger, FromScriptLogger};
 use crossbeam_channel::{unbounded, Sender};
 use embedder_traits::{EmbedderMsg, EmbedderProxy, EmbedderReceiver, EventLoopWaker};
 use env_logger::Builder as EnvLoggerBuilder;
+use euclid::TypedSize2D;
 #[cfg(all(
     not(target_os = "windows"),
     not(target_os = "ios"),
@@ -303,11 +304,16 @@ where
 
             let render_notifier = Box::new(RenderNotifier::new(compositor_proxy.clone()));
 
+            // Cast from `DeviceIndependentPixel` to `DevicePixel`
+            let device_pixel_ratio = coordinates.hidpi_factor.get();
+            let window_size = TypedSize2D::from_untyped(
+                &(opts.initial_window_size.to_f32() / device_pixel_ratio).to_i32().to_untyped());
+
             webrender::Renderer::new(
                 window.gl(),
                 render_notifier,
                 webrender::RendererOptions {
-                    device_pixel_ratio: coordinates.hidpi_factor.get(),
+                    device_pixel_ratio,
                     resource_override_path: opts.shaders_dir.clone(),
                     enable_aa: opts.enable_text_antialiasing,
                     debug_flags: debug_flags,
@@ -323,6 +329,7 @@ where
                     ..Default::default()
                 },
                 None,
+                window_size,
             )
             .expect("Unable to initialize webrender!")
         };