Platform: added window flags to Sdl2Application.

Making resizable window the default to be consistent with GLUT and
others.

src/Platform/Sdl2Application.cpp

@@ -86,10 +86,14 @@ bool Sdl2Application::tryCreateContext(Configuration* configuration) {
     SDL_GL_SetAttribute(SDL_GL_MULTISAMPLEBUFFERS, configuration->sampleCount() > 1 ? 1 : 0);
     SDL_GL_SetAttribute(SDL_GL_MULTISAMPLESAMPLES, configuration->sampleCount());
 
+    /* Flags: if not hidden, set as shown */
+    Uint32 flags(configuration->flags());
+    if(!(configuration->flags() & Configuration::Flag::Hidden)) flags |= SDL_WINDOW_SHOWN;
+
     if(!(window = SDL_CreateWindow(configuration->title().c_str(),
             SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
             configuration->size().x(), configuration->size().y(),
-            SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN))) {
+            SDL_WINDOW_OPENGL|flags))) {
         Error() << "Platform::Sdl2Application::tryCreateContext(): cannot create window";
         std::exit(2);
     }
@@ -183,7 +187,7 @@ void Sdl2Application::setMouseLocked(bool enabled) {
     SDL_SetRelativeMouseMode(enabled ? SDL_TRUE : SDL_FALSE);
 }
 
-Sdl2Application::Configuration::Configuration(): _title("Magnum SDL2 Application"), _size(800, 600), _sampleCount(0) {}
+Sdl2Application::Configuration::Configuration(): _title("Magnum SDL2 Application"), _size(800, 600), _flags(Flag::Resizable), _sampleCount(0) {}
 Sdl2Application::Configuration::~Configuration() = default;
 
 Sdl2Application::InputEvent::Modifiers Sdl2Application::MouseEvent::modifiers() {

src/Platform/Sdl2Application.h

@@ -196,6 +196,29 @@ class Sdl2Application::Configuration {
     Configuration& operator=(Configuration&&) = delete;
 
     public:
+        /**
+         * @brief Window flag
+         *
+         * @see Flags, setFlags()
+         */
+        enum class Flag: Uint32 {
+            Resizable = SDL_WINDOW_RESIZABLE,       /**< Resizable window */
+            Fullscreen = SDL_WINDOW_FULLSCREEN,     /**< Fullscreen window */
+            Hidden = SDL_WINDOW_HIDDEN,             /**< Hidden window */
+            Maximized = SDL_WINDOW_MAXIMIZED,       /**< Maximized window */
+            Minimized = SDL_WINDOW_MINIMIZED,       /**< Minimized window */
+            MouseLocked = SDL_WINDOW_INPUT_GRABBED  /**< Window with mouse locked */
+        };
+
+        /**
+         * @brief Window flags
+         *
+         * @see setFlags()
+         */
+        typedef Corrade::Containers::EnumSet<Flag, Uint32, SDL_WINDOW_RESIZABLE|
+            SDL_WINDOW_FULLSCREEN|SDL_WINDOW_HIDDEN|SDL_WINDOW_MAXIMIZED|
+            SDL_WINDOW_MINIMIZED|SDL_WINDOW_INPUT_GRABBED> Flags;
+
         explicit Configuration();
         ~Configuration();
 
@@ -227,6 +250,20 @@ class Sdl2Application::Configuration {
             return this;
         }
 
+        /** @brief Window flags */
+        inline Flags flags() const { return _flags; }
+
+        /**
+         * @brief Set window flags
+         * @return Pointer to self (for method chaining)
+         *
+         * Default is @ref Flag "Flag::Resizable".
+         */
+        inline Configuration* setFlags(const Flags flags) {
+            _flags = flags;
+            return this;
+        }
+
         /** @brief Sample count */
         inline Int sampleCount() const { return _sampleCount; }
 
@@ -245,9 +282,12 @@ class Sdl2Application::Configuration {
     private:
         std::string _title;
         Vector2i _size;
+        Flags _flags;
         Int _sampleCount;
 };
 
+CORRADE_ENUMSET_OPERATORS(Sdl2Application::Configuration::Flags)
+
 /**
 @brief Base for input events