RWindow::Flash

include/ReWindow/types/Window.h

@@ -324,6 +324,10 @@ public:
     /// Calling this function, therefore, creates the real 'window' object on the operating system.
     [[nodiscard]] virtual bool Open() = 0;
 
+    /// Bring attention to the user, On X11 this flashes the entry for this window in the window list.
+    /// @note If the window is already in focus when this is called nothing happens.
+    void Flash();
+
     /// @returns True if we are definitely running on a software renderer.
     /// @note For some APIs this isn't typically possible.
     [[nodiscard]] virtual bool SoftwareRendered() { return false; }

main.cpp

@@ -87,7 +87,9 @@ int main() {
 	window->OnMouseButtonDownEvent += [&] (MouseButtonDownEvent e) { jlog::Debug(e.Button.Mnemonic + std::to_string(e.Button.ButtonIndex)); };
     window->OnMouseWheelEvent += [&, window] (MouseWheelEvent e) { std::cout << window->GetMouseWheelPersistent() << std::endl; };
 
-	while (!window->IsClosing())
+	while (!window->IsClosing()) {
         window->ManagedRefresh();
+        window->Flash();
+    }
     delete window;
 }

src/platform/linux/OpenGLWindow.cpp

@@ -21,6 +21,7 @@ public:
     Atom windowTypeUtilityAtom;
     XSizeHints hints;
     Cursor invisible_cursor = 0;
+    XWMHints* wm_hints = nullptr;
 };
 
 void* glx_lib = nullptr;

src/platform/linux/VulkanWindow.cpp

@@ -23,6 +23,7 @@ public:
     Atom windowTypeUtilityAtom;
     XSizeHints hints;
     Cursor invisible_cursor = 0;
+    XWMHints* wm_hints = nullptr;
 };
 
 namespace Vulkan {

src/platform/linux/Window.cpp

@@ -20,11 +20,23 @@ public:
     Atom windowTypeUtilityAtom;
     XSizeHints hints;
     Cursor invisible_cursor = 0;
+    XWMHints* wm_hints = nullptr;
 };
 
 
 using namespace ReWindow;
 
+void RWindow::Flash() {
+    if (IsFocused())
+        return;
+
+    if (platform->wm_hints == nullptr)
+        platform->wm_hints = XAllocWMHints();
+
+    platform->wm_hints->flags = XUrgencyHint;
+    XSetWMHints(platform->display, platform->window, platform->wm_hints);
+}
+
 RWindow::RWindow() {
 platform = new Platform();
 extant = this;
@@ -128,8 +140,12 @@ void RWindow::PollEvents() {
         if (platform->xev.type == FocusIn) {
             Logger::Debug(std::format("Event'{}'", "FocusIn"));
             XAutoRepeatOff(platform->display);
-            SetFlag(WindowFlag::IN_FOCUS, true);
 
+            if (platform->wm_hints) {
+                platform->wm_hints->flags &= ~XUrgencyHint;
+                XSetWMHints(platform->display, platform->window, platform->wm_hints);
+                XFree(platform->wm_hints);
+            }
             if (!cursor_visible)
                 XDefineCursor(platform->display, platform->window, platform->invisible_cursor);
 
@@ -137,17 +153,18 @@ void RWindow::PollEvents() {
             XGetWindowAttributes(platform->display, platform->window, &platform->windowAttributes);
             render_area_position =  { platform->windowAttributes.x, platform->windowAttributes.y };
             processFocusIn();
+            focused = true;
         }
 
         if (platform->xev.type == FocusOut) {
             Logger::Debug(std::format("Event '{}'", "FocusOut"));
             XAutoRepeatOn(platform->display);
 
-            SetFlag(WindowFlag::IN_FOCUS, false);
             if (!cursor_visible)
                 XUndefineCursor(platform->display, platform->window);
 
             processFocusOut();
+            focused = false;
         }
 
         if (platform->xev.type == KeyRelease) {