LibGUI: Support using a bitmap as override cursor

Userland/Libraries/LibGUI/Widget.cpp

@@ -1036,14 +1036,23 @@ Gfx::IntRect Widget::children_clip_rect() const
     return rect();
 }
 
-void Widget::set_override_cursor(Gfx::StandardCursor cursor)
+void Widget::set_override_cursor(AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> cursor)
 {
-    if (m_override_cursor == cursor)
+    auto const& are_cursors_the_same = [](AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> const& a, AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> const& b) {
+        if (a.has<Gfx::StandardCursor>() != b.has<Gfx::StandardCursor>())
+            return false;
+        if (a.has<Gfx::StandardCursor>())
+            return a.get<Gfx::StandardCursor>() == b.get<Gfx::StandardCursor>();
+        return a.get<NonnullRefPtr<Gfx::Bitmap>>().ptr() == b.get<NonnullRefPtr<Gfx::Bitmap>>().ptr();
+    };
+
+    if (are_cursors_the_same(m_override_cursor, cursor))
         return;
 
-    m_override_cursor = cursor;
+    m_override_cursor = move(cursor);
-    if (auto* window = this->window())
+    if (auto* window = this->window()) {
         window->update_cursor({});
+    }
 }
 
 bool Widget::load_from_gml(const StringView& gml_string)

Userland/Libraries/LibGUI/Widget.h

@@ -9,6 +9,7 @@
 #include <AK/EnumBits.h>
 #include <AK/JsonObject.h>
 #include <AK/String.h>
+#include <AK/Variant.h>
 #include <LibCore/Object.h>
 #include <LibGUI/Event.h>
 #include <LibGUI/FocusPolicy.h>
@@ -272,8 +273,8 @@ public:
 
     virtual Gfx::IntRect children_clip_rect() const;
 
-    Gfx::StandardCursor override_cursor() const { return m_override_cursor; }
+    AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> override_cursor() const { return m_override_cursor; }
-    void set_override_cursor(Gfx::StandardCursor);
+    void set_override_cursor(AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>>);
 
     bool load_from_gml(const StringView&);
     bool load_from_gml(const StringView&, RefPtr<Core::Object> (*unregistered_child_handler)(const String&));
@@ -373,7 +374,7 @@ private:
     WeakPtr<Widget> m_focus_proxy;
     FocusPolicy m_focus_policy { FocusPolicy::NoFocus };
 
-    Gfx::StandardCursor m_override_cursor { Gfx::StandardCursor::None };
+    AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> m_override_cursor { Gfx::StandardCursor::None };
 };
 
 inline Widget* Widget::parent_widget()

Userland/Libraries/LibGUI/Window.cpp

@@ -317,21 +317,28 @@ void Window::make_window_manager(unsigned event_mask)
     GUI::WindowManagerServerConnection::the().async_set_manager_window(m_window_id);
 }
 
+bool Window::are_cursors_the_same(AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> const& left, AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> const& right) const
+{
+    if (left.has<Gfx::StandardCursor>() != right.has<Gfx::StandardCursor>())
+        return false;
+    if (left.has<Gfx::StandardCursor>())
+        return left.get<Gfx::StandardCursor>() == right.get<Gfx::StandardCursor>();
+    return left.get<NonnullRefPtr<Gfx::Bitmap>>().ptr() == right.get<NonnullRefPtr<Gfx::Bitmap>>().ptr();
+}
+
 void Window::set_cursor(Gfx::StandardCursor cursor)
 {
-    if (m_cursor == cursor)
+    if (are_cursors_the_same(m_cursor, cursor))
         return;
     m_cursor = cursor;
-    m_custom_cursor = nullptr;
     update_cursor();
 }
 
-void Window::set_cursor(const Gfx::Bitmap& cursor)
+void Window::set_cursor(NonnullRefPtr<Gfx::Bitmap> cursor)
 {
-    if (m_custom_cursor == &cursor)
+    if (are_cursors_the_same(m_cursor, cursor))
         return;
-    m_cursor = Gfx::StandardCursor::None;
+    m_cursor = cursor;
-    m_custom_cursor = &cursor;
     update_cursor();
 }
 
@@ -1135,21 +1142,22 @@ void Window::set_progress(Optional<int> progress)
 
 void Window::update_cursor()
 {
-    Gfx::StandardCursor new_cursor;
+    auto new_cursor = m_cursor;
 
-    if (m_hovered_widget && m_hovered_widget->override_cursor() != Gfx::StandardCursor::None)
+    if (m_hovered_widget) {
-        new_cursor = m_hovered_widget->override_cursor();
+        auto override_cursor = m_hovered_widget->override_cursor();
-    else
+        if (override_cursor.has<NonnullRefPtr<Gfx::Bitmap>>() || override_cursor.get<Gfx::StandardCursor>() != Gfx::StandardCursor::None)
-        new_cursor = m_cursor;
+            new_cursor = move(override_cursor);
+    }
 
-    if (!m_custom_cursor && m_effective_cursor == new_cursor)
+    if (are_cursors_the_same(m_effective_cursor, new_cursor))
         return;
     m_effective_cursor = new_cursor;
 
-    if (m_custom_cursor)
+    if (new_cursor.has<NonnullRefPtr<Gfx::Bitmap>>())
-        WindowServerConnection::the().async_set_window_custom_cursor(m_window_id, m_custom_cursor->to_shareable_bitmap());
+        WindowServerConnection::the().async_set_window_custom_cursor(m_window_id, new_cursor.get<NonnullRefPtr<Gfx::Bitmap>>()->to_shareable_bitmap());
     else
-        WindowServerConnection::the().async_set_window_cursor(m_window_id, (u32)m_effective_cursor);
+        WindowServerConnection::the().async_set_window_cursor(m_window_id, (u32)new_cursor.get<Gfx::StandardCursor>());
 }
 
 void Window::focus_a_widget_if_possible(FocusSource source)

Userland/Libraries/LibGUI/Window.h

@@ -9,6 +9,7 @@
 #include <AK/Function.h>
 #include <AK/OwnPtr.h>
 #include <AK/String.h>
+#include <AK/Variant.h>
 #include <AK/WeakPtr.h>
 #include <LibCore/Object.h>
 #include <LibGUI/FocusSource.h>
@@ -169,7 +170,7 @@ public:
     void set_resize_aspect_ratio(const Optional<Gfx::IntSize>& ratio);
 
     void set_cursor(Gfx::StandardCursor);
-    void set_cursor(const Gfx::Bitmap&);
+    void set_cursor(NonnullRefPtr<Gfx::Bitmap>);
 
     void set_icon(const Gfx::Bitmap*);
     void apply_icon();
@@ -240,6 +241,8 @@ private:
     void flip(const Vector<Gfx::IntRect, 32>& dirty_rects);
     void force_update();
 
+    bool are_cursors_the_same(AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> const&, AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> const&) const;
+
     WeakPtr<Widget> m_previously_focused_widget;
 
     OwnPtr<WindowBackingStore> m_front_store;
@@ -248,7 +251,6 @@ private:
     NonnullRefPtr<Menubar> m_menubar;
 
     RefPtr<Gfx::Bitmap> m_icon;
-    RefPtr<Gfx::Bitmap> m_custom_cursor;
     int m_window_id { 0 };
     float m_opacity_when_windowless { 1.0f };
     float m_alpha_hit_threshold { 0.0f };
@@ -265,8 +267,8 @@ private:
     Gfx::IntSize m_base_size;
     Color m_background_color { Color::WarmGray };
     WindowType m_window_type { WindowType::Normal };
-    Gfx::StandardCursor m_cursor { Gfx::StandardCursor::None };
+    AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> m_cursor { Gfx::StandardCursor::None };
-    Gfx::StandardCursor m_effective_cursor { Gfx::StandardCursor::None };
+    AK::Variant<Gfx::StandardCursor, NonnullRefPtr<Gfx::Bitmap>> m_effective_cursor { Gfx::StandardCursor::None };
     bool m_is_active_input { false };
     bool m_has_alpha_channel { false };
     bool m_double_buffering_enabled { true };