WindowPosition::Centered doesn't work correctly when scale_factor is not 1.0

[rparrett]

Bevy version

bevy main

Relevant system information

AdapterInfo { name: "Apple M1 Max", vendor: 0, device: 0, device_type: IntegratedGpu, backend: Metal }

Built-in Liquid Retina XDR Display
16-inch (3456 × 2234)

What you did

use bevy::prelude::*;

fn main() {
    App::new()
        .insert_resource(WindowDescriptor {
            position: WindowPosition::Centered(MonitorSelection::Primary),
            ..default()
        })
        .add_plugins(DefaultPlugins)
        .add_startup_system(setup)
        .run();
}

fn setup(windows: Res<Windows>) {
    info!("{:?}", windows.get_primary());
}

What went wrong

Window was in the bottom right region of the screen, clearly not in the center, but still completely on-screen.

Some(
    Window {
        id: WindowId(00000000-0000-0000-0000-000000000000),
        requested_width: 1280.0,
        requested_height: 720.0,
        physical_width: 2560,
        physical_height: 1442,
        resize_constraints: WindowResizeConstraints {
            min_width: 180.0,
            min_height: 120.0,
            max_width: inf,
            max_height: inf
        },
        position: Some(IVec2(896, 700)),
        scale_factor_override: None,
        backend_scale_factor: 2.0,
        title: "app",
        present_mode: Fifo,
        resizable: true,
        decorations: true,
        cursor_icon: Default,
        cursor_visible: true,
        cursor_locked: false,
        physical_cursor_position: None,
        raw_window_handle: RawWindowHandleWrapper(AppKit(AppKitHandle { ns_window: 0x116f04da0, ns_view: 0x116e498f0 })),
        focused: true,
        mode: Windowed,
        canvas: None,
        fit_canvas_to_parent: false,
        command_queue: []
    }
)

Additional information

PR incoming

Thanks to @Rigidity for reporting via discord.