From f95c4cfaba1a3ee6e35bd3deac0973895a555598 Mon Sep 17 00:00:00 2001
From: Mukilan Thiyagarajan <mukilan@igalia.com>
Date: Fri, 1 Nov 2024 16:05:43 +0530
Subject: [PATCH] servoshell: fix logical screen size calculation (#34096)

Signed-off-by: Mukilan Thiyagarajan <mukilan@igalia.com>
---
 ports/servoshell/desktop/headed_window.rs |  8 ++++----
 ports/servoshell/egl/servo_glue.rs        | 11 ++++++-----
 2 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/ports/servoshell/desktop/headed_window.rs b/ports/servoshell/desktop/headed_window.rs
index 70dc1d480e5..8d71fce5e44 100644
--- a/ports/servoshell/desktop/headed_window.rs
+++ b/ports/servoshell/desktop/headed_window.rs
@@ -99,9 +99,9 @@ impl Window {
             || (monitor.size(), monitor.scale_factor()),
             |size| (PhysicalSize::new(size.width, size.height), 1.0),
         );
-        let screen_scale: Scale<f64, DevicePixel, DeviceIndependentPixel> =
+        let screen_scale: Scale<f64, DeviceIndependentPixel, DevicePixel> =
             Scale::new(screen_scale);
-        let screen_size = (winit_size_to_euclid_size(screen_size).to_f64() * screen_scale).to_u32();
+        let screen_size = (winit_size_to_euclid_size(screen_size).to_f64() / screen_scale).to_u32();
 
         // Initialize surfman
         let display_handle = winit_window
@@ -534,9 +534,9 @@ impl WindowMethods for Window {
         let window_origin = self.winit_window.outer_position().unwrap_or_default();
         let window_origin = winit_position_to_euclid_point(window_origin).to_i32();
         let window_rect = DeviceIntRect::from_origin_and_size(window_origin, window_size);
-        let window_scale: Scale<f64, DevicePixel, DeviceIndependentPixel> =
+        let window_scale: Scale<f64, DeviceIndependentPixel, DevicePixel> =
             Scale::new(self.winit_window.scale_factor());
-        let window_rect = (window_rect.to_f64() * window_scale).to_i32();
+        let window_rect = (window_rect.to_f64() / window_scale).to_i32();
 
         let viewport_origin = DeviceIntPoint::zero(); // bottom left
         let viewport_size = winit_size_to_euclid_size(self.winit_window.inner_size()).to_f32();
diff --git a/ports/servoshell/egl/servo_glue.rs b/ports/servoshell/egl/servo_glue.rs
index d9b32401c34..9674e357aae 100644
--- a/ports/servoshell/egl/servo_glue.rs
+++ b/ports/servoshell/egl/servo_glue.rs
@@ -23,6 +23,7 @@ use servo::keyboard_types::{Key, KeyState, KeyboardEvent};
 use servo::script_traits::{
     MediaSessionActionType, MouseButton, TouchEventType, TouchId, TraversalDirection,
 };
+use servo::servo_geometry::DeviceIndependentPixel;
 use servo::style_traits::DevicePixel;
 use servo::webrender_api::units::DeviceIntRect;
 use servo::webrender_api::ScrollLocation;
@@ -56,7 +57,7 @@ impl Coordinates {
 pub(super) struct ServoWindowCallbacks {
     host_callbacks: Box<dyn HostTrait>,
     coordinates: RefCell<Coordinates>,
-    density: f32,
+    hidpi_factor: Scale<f32, DeviceIndependentPixel, DevicePixel>,
     rendering_context: RenderingContext,
 }
 
@@ -64,13 +65,13 @@ impl ServoWindowCallbacks {
     pub(super) fn new(
         host_callbacks: Box<dyn HostTrait>,
         coordinates: RefCell<Coordinates>,
-        density: f32,
+        hidpi_factor: f32,
         rendering_context: RenderingContext,
     ) -> Self {
         Self {
             host_callbacks,
             coordinates,
-            density,
+            hidpi_factor: Scale::new(hidpi_factor),
             rendering_context,
         }
     }
@@ -690,14 +691,14 @@ impl EmbedderMethods for ServoEmbedderCallbacks {
 impl WindowMethods for ServoWindowCallbacks {
     fn get_coordinates(&self) -> EmbedderCoordinates {
         let coords = self.coordinates.borrow();
-        let screen_size = (coords.viewport.size.to_f32() * Scale::new(self.density)).to_i32();
+        let screen_size = (coords.viewport.size.to_f32() / self.hidpi_factor).to_i32();
         EmbedderCoordinates {
             viewport: coords.viewport.to_box2d(),
             framebuffer: coords.framebuffer,
             window_rect: Box2D::from_origin_and_size(Point2D::zero(), screen_size),
             screen_size,
             available_screen_size: screen_size,
-            hidpi_factor: Scale::new(self.density),
+            hidpi_factor: self.hidpi_factor,
         }
     }