SDL2 context: keyboard handling for basic keys.

src/Contexts/Sdl2Context.cpp

@@ -82,6 +82,12 @@ int Sdl2Context::exec() {
                             _redraw = true;
                             break;
                     } break;
+                case SDL_KEYDOWN:
+                    keyPressEvent(static_cast<Key>(event.key.keysym.sym), event.key.repeat);
+                    break;
+                case SDL_KEYUP:
+                    keyReleaseEvent(static_cast<Key>(event.key.keysym.sym));
+                    break;
                 case SDL_MOUSEBUTTONDOWN:
                 case SDL_MOUSEBUTTONUP:
                     mouseEvent(static_cast<MouseButton>(event.button.button),

src/Contexts/Sdl2Context.h

@@ -30,7 +30,7 @@ namespace Magnum { namespace Contexts {
 /** @nosubgrouping
 @brief SDL2 context
 
-Currently doesn't have any mouse/keyboard handling.
+Supports keyboard and mouse handling.
 
 You need to implement at least drawEvent() and viewportEvent() to be able to
 draw on the screen.
@@ -75,6 +75,37 @@ class Sdl2Context: public AbstractContext {
 
         /*@}*/
 
+        /** @{ @name Keyboard handling */
+    public:
+        /**
+         * @brief Key
+         * @see keyPressEvent(), keyReleaseEvent()
+         */
+        enum class Key: SDL_Keycode {
+            Up = SDLK_UP,                   /**< Up arrow */
+            Down = SDLK_DOWN,               /**< Down arrow */
+            Left = SDLK_LEFT,               /**< Left arrow */
+            Right = SDLK_RIGHT,             /**< Right arrow */
+            Plus = SDLK_PLUS,               /**< Plus */
+            Minus = SDLK_MINUS              /**< Minus */
+        };
+
+    protected:
+        /**
+         * @brief Key press event
+         * @param key       Key pressed
+         * @param repeat    Non-zero if this is a key repeat
+         */
+        inline virtual void keyPressEvent(Key key, Uint8 repeat) {}
+
+        /**
+         * @brief Key release event
+         * @param key       Key release
+         */
+        inline virtual void keyReleaseEvent(Key key) {}
+
+        /*@}*/
+
         /** @{ @name Mouse handling */
 
     public: