linux tranparency

Cargo.toml

@@ -73,3 +73,6 @@ windows = { version = "0.58", features = [
     "Win32_Graphics_Dwm",
     "Win32_UI_WindowsAndMessaging",
 ] }
+
+[target.'cfg(target_os = "linux")'.dependencies]
+x11-dl = "2"

src/bin/layers_shell.rs

@@ -328,7 +328,58 @@ fn set_window_alpha(window: &Window, alpha: f32) {
     }
 }
 
-#[cfg(not(target_os = "windows"))]
+#[cfg(target_os = "linux")]
+fn set_window_alpha(window: &Window, alpha: f32) {
+    use raw_window_handle::{RawDisplayHandle, RawWindowHandle};
+    use std::ffi::CString;
+    use x11_dl::xlib;
+
+    let Ok(win_handle) = window.window_handle() else { return; };
+    let Ok(disp_handle) = window.display_handle() else { return; };
+
+    let (display_ptr, xid) = match (win_handle.as_raw(), disp_handle.as_raw()) {
+        (RawWindowHandle::Xlib(win), RawDisplayHandle::Xlib(disp)) => {
+            let Some(dp) = disp.display else { return; };
+            (dp.as_ptr() as *mut xlib::Display, win.window as xlib::Window)
+        }
+        _ => return,
+    };
+
+    let xlib = match xlib::Xlib::open() {
+        Ok(x) => x,
+        Err(_) => return,
+    };
+
+    let atom_name = match CString::new("_NET_WM_WINDOW_OPACITY") {
+        Ok(s) => s,
+        Err(_) => return,
+    };
+    let cardinal_name = match CString::new("CARDINAL") {
+        Ok(s) => s,
+        Err(_) => return,
+    };
+
+    let opacity = (alpha.clamp(0.0, 1.0) * u32::MAX as f32).round() as u32;
+
+    unsafe {
+        let atom = (xlib.XInternAtom)(display_ptr, atom_name.as_ptr(), xlib::False);
+        let cardinal = (xlib.XInternAtom)(display_ptr, cardinal_name.as_ptr(), xlib::False);
+        if atom == 0 || cardinal == 0 { return; }
+        (xlib.XChangeProperty)(
+            display_ptr,
+            xid,
+            atom,
+            cardinal,
+            32,
+            xlib::PropModeReplace,
+            &opacity as *const u32 as *const u8,
+            1,
+        );
+        (xlib.XFlush)(display_ptr);
+    }
+}
+
+#[cfg(not(any(target_os = "windows", target_os = "linux")))]
 fn set_window_alpha(_window: &Window, _alpha: f32) {}
 
 #[cfg(target_os = "windows")]