fix(window): handle window movement across monitors with different scaling (#3675)

Author: Slinetrac

backend/tauri/src/ipc.rs

@@ -985,6 +985,38 @@ pub async fn get_clash_ws_connections_state(
     Ok(ws_connector.state())
 }
 
+/// Move window to another monitor
+#[tauri::command]
+#[specta::specta]
+pub fn move_window_to_other_monitor(
+    window: tauri::Window,
+    target_monitor_index: usize,
+) -> Result<()> {
+    crate::utils::window_manager::move_window_to_other_monitor(window, target_monitor_index)?;
+    Ok(())
+}
+
+/// Center window on current monitor
+#[tauri::command]
+#[specta::specta]
+pub fn center_window(window: tauri::Window) -> Result<()> {
+    crate::utils::window_manager::center_window(&window)?;
+    Ok(())
+}
+
+/// Get available monitors
+#[tauri::command]
+#[specta::specta]
+pub fn get_available_monitors(
+    window: tauri::Window,
+) -> Result<Vec<crate::utils::window_manager::MonitorInfo>> {
+    let monitors = crate::utils::window_manager::get_available_monitors(window)?;
+    Ok(monitors
+        .iter()
+        .map(|(id, monitor)| ((*id, monitor)).into())
+        .collect())
+}
+
 // Updater block
 
 #[derive(Default, Clone, serde::Serialize, serde::Deserialize, specta::Type)]

backend/tauri/src/lib.rs

@@ -272,6 +272,10 @@ pub fn run() -> std::io::Result<()> {
             ipc::get_core_dir,
             // clash layer
             ipc::get_clash_ws_connections_state,
+            // window management
+            ipc::move_window_to_other_monitor,
+            ipc::center_window,
+            ipc::get_available_monitors,
             // updater layer
             ipc::check_update,
         ])

backend/tauri/src/utils/mod.rs

@@ -17,6 +17,7 @@ pub mod open;
 
 pub mod dock;
 pub mod sudo;
+pub mod window_manager;
 
 #[cfg(test)]
 #[cfg(windows)]

backend/tauri/src/utils/window_manager.rs

@@ -0,0 +1,198 @@
+//! Window management utilities for multi-monitor setups with different scaling factors
+use display_info::DisplayInfo;
+use serde::{Deserialize, Serialize};
+use specta::Type;
+use tauri::{Monitor, PhysicalPosition, PhysicalSize, Position, Size, Window};
+
+/// Simplified monitor information for IPC
+#[derive(Debug, Clone, Serialize, Deserialize, Type)]
+pub struct MonitorInfo {
+    pub id: usize,
+    pub name: String,
+    pub position: (i32, i32),
+    pub size: (u32, u32),
+    pub scale_factor: f64,
+}
+
+impl From<(usize, &Monitor)> for MonitorInfo {
+    fn from((id, monitor): (usize, &Monitor)) -> Self {
+        let position = monitor.position();
+        let size = monitor.size();
+        Self {
+            id,
+            name: format!("Monitor {}", id),
+            position: (position.x, position.y),
+            size: (size.width, size.height),
+            scale_factor: monitor.scale_factor(),
+        }
+    }
+}
+
+/// Get the scale factor for a specific monitor
+fn get_monitor_scale_factor(monitor: &Monitor) -> f64 {
+    // Try to get the scale factor from the display info
+    if let Ok(displays) = DisplayInfo::all() {
+        for display in displays {
+            // Match the monitor by position and size
+            let monitor_pos = monitor.position();
+            let monitor_size = monitor.size();
+
+            if display.x == monitor_pos.x
+                && display.y == monitor_pos.y
+                && display.width as u32 == monitor_size.width
+                && display.height as u32 == monitor_size.height
+            {
+                return display.scale_factor as f64;
+            }
+        }
+    }
+
+    // Fallback to the monitor's scale factor if we can't find it in display info
+    monitor.scale_factor()
+}
+
+/// Move window to another monitor while correctly handling different scaling factors
+pub fn move_window_to_other_monitor(
+    window: Window,
+    target_monitor_index: usize,
+) -> tauri::Result<()> {
+    let monitors = get_available_monitors(window.clone())?;
+
+    let (_index, target_monitor) =
+        monitors
+            .get(target_monitor_index)
+            .ok_or(tauri::Error::InvalidArgs(
+                "target_monitor_index",
+                "Index out of bounds",
+                serde_json::Error::io(std::io::Error::new(
+                    std::io::ErrorKind::InvalidInput,
+                    "Index out of bounds",
+                )),
+            ))?;
+
+    // Get current monitor
+    let current_monitor = window
+        .current_monitor()?
+        .unwrap_or_else(|| target_monitor.clone());
+
+    // Get scale factors for current and target monitors
+    let current_scale_factor = get_monitor_scale_factor(&current_monitor);
+    let target_scale_factor = get_monitor_scale_factor(target_monitor);
+
+    // Get current window size
+    let window_size = window.outer_size()?;
+
+    // Calculate scaled size for target monitor
+    let scale_ratio = current_scale_factor / target_scale_factor;
+    let target_width = (window_size.width as f64 * scale_ratio).round() as u32;
+    let target_height = (window_size.height as f64 * scale_ratio).round() as u32;
+
+    // Set window size first to prevent flickering
+    window.set_size(Size::Physical(PhysicalSize {
+        width: target_width,
+        height: target_height,
+    }))?;
+
+    // Move window to target monitor position
+    let pos = target_monitor.position();
+    window.set_position(Position::Physical(PhysicalPosition { x: pos.x, y: pos.y }))?;
+
+    Ok(())
+}
+
+/// Resize window while correctly handling monitor scaling factors
+fn resize_window(window: &Window, screen_share: f64) -> tauri::Result<()> {
+    let monitor = window.current_monitor().unwrap().unwrap();
+    let monitor_size = monitor.size();
+
+    // Get the monitor's scale factor
+    let scale_factor = get_monitor_scale_factor(&monitor);
+
+    // Calculate size accounting for scale factor
+    let scaled_size: PhysicalSize<u32> = PhysicalSize {
+        width: ((monitor_size.width as f64 * screen_share) / scale_factor).round() as u32,
+        height: ((monitor_size.height as f64 * screen_share) / scale_factor).round() as u32,
+    };
+
+    window.set_size(Size::Physical(scaled_size))?;
+    Ok(())
+}
+
+/// Center window on current monitor while correctly handling scaling factors
+#[cfg(windows)]
+pub fn center_window(window: &Window) -> tauri::Result<()> {
+    use windows_sys::Win32::{
+        Foundation::RECT,
+        UI::WindowsAndMessaging::{SPI_GETWORKAREA, SystemParametersInfoW},
+    };
+
+    // Get current monitor
+    let monitor = window.current_monitor()?.ok_or(tauri::Error::InvalidArgs(
+        "current_monitor",
+        "No current monitor",
+        serde_json::Error::io(std::io::Error::new(
+            std::io::ErrorKind::InvalidInput,
+            "No current monitor",
+        )),
+    ))?;
+    let scale_factor = get_monitor_scale_factor(&monitor);
+
+    // Get work area
+    let mut work_area = RECT {
+        left: 0,
+        top: 0,
+        right: 0,
+        bottom: 0,
+    };
+    unsafe {
+        SystemParametersInfoW(SPI_GETWORKAREA, 0, &mut work_area as *mut _ as *mut _, 0);
+    }
+
+    let work_area_width = (work_area.right - work_area.left) as u32;
+    let work_area_height = (work_area.bottom - work_area.top) as u32;
+    let work_area_x = work_area.left as i32;
+    let work_area_y = work_area.top as i32;
+
+    let window_size = window.outer_size()?;
+
+    // Adjust for scale factor
+    let adjusted_window_width = (window_size.width as f64 / scale_factor).round() as i32;
+    let adjusted_window_height = (window_size.height as f64 / scale_factor).round() as i32;
+
+    let new_x = work_area_x + (work_area_width as i32 - adjusted_window_width) / 2;
+    let new_y = work_area_y + (work_area_height as i32 - adjusted_window_height) / 2;
+
+    window.set_position(Position::Physical(PhysicalPosition { x: new_x, y: new_y }))?;
+    Ok(())
+}
+
+#[cfg(target_os = "macos")]
+pub fn center_window(window: &Window) -> tauri::Result<()> {
+    window.center();
+    Ok(())
+}
+
+/// Get available monitors sorted by position
+pub fn get_available_monitors(
+    window: tauri::Window,
+) -> tauri::Result<Vec<(usize, tauri::Monitor)>> {
+    let mut monitors = window.available_monitors()?;
+    monitors.sort_by(|a, b| {
+        let a_pos = a.position();
+        let b_pos = b.position();
+        let a_size = a.size();
+        let b_size = b.size();
+        let a_val =
+            (a_pos.y + 200) * 10 / a_size.height as i32 + (a_pos.x + 300) / a_size.width as i32;
+        let b_val =
+            (b_pos.y + 200) * 10 / b_size.height as i32 + (b_pos.x + 300) / b_size.width as i32;
+
+        a_val.cmp(&b_val)
+    });
+
+    monitors
+        .iter()
+        .enumerate()
+        .map(|(i, m)| Ok((i, m.clone())))
+        .collect()
+}

frontend/interface/src/ipc/bindings.ts

@@ -1,9 +1,6 @@
 /** tauri-specta globals **/
 
-import {
-  Channel as TAURI_CHANNEL,
-  invoke as TAURI_INVOKE,
-} from '@tauri-apps/api/core'
+import { invoke as TAURI_INVOKE } from '@tauri-apps/api/core'
 import * as TAURI_API_EVENT from '@tauri-apps/api/event'
 import { type WebviewWindow as __WebviewWindow__ } from '@tauri-apps/api/webviewWindow'
 
@@ -720,6 +717,49 @@ export const commands = {
       else return { status: 'error', error: e as any }
     }
   },
+  /**
+   * Move window to another monitor
+   */
+  async moveWindowToOtherMonitor(
+    targetMonitorIndex: number,
+  ): Promise<Result<null, string>> {
+    try {
+      return {
+        status: 'ok',
+        data: await TAURI_INVOKE('move_window_to_other_monitor', {
+          targetMonitorIndex,
+        }),
+      }
+    } catch (e) {
+      if (e instanceof Error) throw e
+      else return { status: 'error', error: e as any }
+    }
+  },
+  /**
+   * Center window on current monitor
+   */
+  async centerWindow(): Promise<Result<null, string>> {
+    try {
+      return { status: 'ok', data: await TAURI_INVOKE('center_window') }
+    } catch (e) {
+      if (e instanceof Error) throw e
+      else return { status: 'error', error: e as any }
+    }
+  },
+  /**
+   * Get available monitors
+   */
+  async getAvailableMonitors(): Promise<Result<MonitorInfo[], string>> {
+    try {
+      return {
+        status: 'ok',
+        data: await TAURI_INVOKE('get_available_monitors'),
+      }
+    } catch (e) {
+      if (e instanceof Error) throw e
+      else return { status: 'error', error: e as any }
+    }
+  },
   async checkUpdate(): Promise<Result<UpdateWrapper | null, string>> {
     try {
       return { status: 'ok', data: await TAURI_INVOKE('check_update') }
@@ -1168,6 +1208,16 @@ export type MergeProfileBuilder = {
    */
   updated: number | null
 }
+/**
+ * Simplified monitor information for IPC
+ */
+export type MonitorInfo = {
+  id: number
+  name: string
+  position: [number, number]
+  size: [number, number]
+  scale_factor: number
+}
 export type NetworkStatisticWidgetConfig =
   | { kind: 'disabled' }
   | { kind: 'enabled'; value: StatisticWidgetVariant }