Platform: implemented GlfwApplication::MouseMoveEvent::buttons().

Improves feature parity with Sdl2Application.

doc/changelog.dox

@@ -55,6 +55,11 @@ See also:
 -   Ability to convert @ref Math::BoolVector from and to external
     representation
 
+@subsubsection changelog-latest-new-platform Platform libraries
+
+-   Implemented @ref Platform::GlfwApplication::MouseMoveEvent::buttons() for
+    feature parity with @ref Platform::Sdl2Application
+
 @subsection changelog-latest-changes Changes and improvements
 
 @subsubsection changelog-latest-changes-audio Audio library

src/Magnum/Platform/GlfwApplication.cpp

@@ -395,6 +395,20 @@ void GlfwApplication::staticKeyEvent(GLFWwindow* const window, const int key, in
     }
 }
 
+auto GlfwApplication::MouseMoveEvent::buttons() -> Buttons {
+    if(!_buttons) {
+        _buttons = Buttons{};
+        for(const Int button: {GLFW_MOUSE_BUTTON_LEFT,
+                               GLFW_MOUSE_BUTTON_MIDDLE,
+                               GLFW_MOUSE_BUTTON_RIGHT}) {
+            if(glfwGetMouseButton(_window, button) == GLFW_PRESS)
+                *_buttons |= Button(1 << button);
+        }
+    }
+
+    return *_buttons;
+}
+
 auto GlfwApplication::MouseMoveEvent::modifiers() -> Modifiers {
     if(!_modifiers) _modifiers = currentGlfwModifiers(_window);
     return *_modifiers;

src/Magnum/Platform/GlfwApplication.h

@@ -1193,6 +1193,31 @@ class GlfwApplication::MouseMoveEvent: public GlfwApplication::InputEvent {
     friend GlfwApplication;
 
     public:
+        /**
+         * @brief Mouse button
+         *
+         * @see @ref Buttons, @ref buttons()
+         */
+        enum class Button: UnsignedInt {
+            Left = 1 << GLFW_MOUSE_BUTTON_LEFT,     /**< Left button */
+            Middle = 1 << GLFW_MOUSE_BUTTON_MIDDLE, /**< Middle button */
+            Right = 1 << GLFW_MOUSE_BUTTON_RIGHT    /**< Right button */
+        };
+
+        /**
+         * @brief Set of mouse buttons
+         *
+         * @see @ref buttons()
+         */
+        typedef Containers::EnumSet<Button> Buttons;
+
+        /**
+         * @brief Mouse buttons
+         *
+         * Lazily populated on first request.
+         */
+        Buttons buttons();
+
         /** @brief Position */
         Vector2i position() const { return _position; }
 
@@ -1207,6 +1232,7 @@ class GlfwApplication::MouseMoveEvent: public GlfwApplication::InputEvent {
         explicit MouseMoveEvent(GLFWwindow* window, const Vector2i& position): _window{window}, _position{position} {}
 
         GLFWwindow* _window;
+        Containers::Optional<Buttons> _buttons;
         const Vector2i _position;
         Containers::Optional<Modifiers> _modifiers;
 };