Fix X11 support and add floating window hint for tiling WMs

Author: pepc84

Cargo.lock

@@ -8,10 +8,11 @@ workspace = true
 
 [features]
 wayland = ["glfw/wayland"]
-x11 = []
+x11 = ["dep:x11"]
 static-link = ["glfw/static-link"]
 
 [dependencies]
+x11 = { version = "2", features = ["xlib"], optional = true }
 bevy = { workspace = true }
 glfw = "0.60.0"
 processing_core = { workspace = true }

crates/processing_glfw/Cargo.toml

@@ -70,6 +70,35 @@ impl GlfwContext {
             .unwrap();
 
         window.set_all_polling(true);
+
+        // Set _NET_WM_WINDOW_TYPE_DIALOG so tiling WMs (i3, sway) float the window
+        #[cfg(all(target_os = "linux", feature = "x11"))]
+        unsafe {
+            use std::ffi::CString;
+            let display = window.glfw.get_x11_display() as *mut x11::xlib::Display;
+            let xwindow = window.get_x11_window() as x11::xlib::Window;
+            let net_wm_window_type = x11::xlib::XInternAtom(
+                display,
+                CString::new("_NET_WM_WINDOW_TYPE").unwrap().as_ptr(),
+                0,
+            );
+            let net_wm_window_type_dialog = x11::xlib::XInternAtom(
+                display,
+                CString::new("_NET_WM_WINDOW_TYPE_DIALOG").unwrap().as_ptr(),
+                0,
+            );
+            x11::xlib::XChangeProperty(
+                display,
+                xwindow,
+                net_wm_window_type,
+                x11::xlib::XA_ATOM,
+                32,
+                x11::xlib::PropModeReplace,
+                &net_wm_window_type_dialog as *const _ as *const u8,
+                1,
+            );
+        }
+
         window.show();
 
         Ok(Self {

crates/processing_glfw/src/lib.rs

@@ -14,7 +14,7 @@ crate-type = ["cdylib"]
 default = ["wayland", "static-link"]
 wayland = ["processing/wayland", "processing_glfw/wayland"]
 static-link = ["processing_glfw/static-link"]
-x11 = ["processing/x11"]
+x11 = ["processing/x11", "processing_glfw/x11"]
 webcam = ["processing/webcam", "dep:processing_webcam"]
 cuda = ["dep:processing_cuda", "processing_cuda/cuda", "processing/cuda"]