Plaftorm: Add cursor management support

src/Magnum/Platform/GlfwApplication.cpp

@@ -222,6 +222,42 @@ void GlfwApplication::setWindowTitle(const std::string& title) {
     glfwSetWindowTitle(_window, title.data());
 }
 
+void GlfwApplication::createCursor(Cursor cursor) {
+    if(!_cursors[static_cast<UnsignedInt>(cursor)]) {
+        int cursor_type;
+
+        switch(cursor) {
+            case Cursor::Arrow:
+                cursor_type = GLFW_ARROW_CURSOR;
+                break;
+            case Cursor::IBeam:
+                cursor_type = GLFW_IBEAM_CURSOR;
+                break;
+            case Cursor::Crosshair:
+                cursor_type = GLFW_CROSSHAIR_CURSOR;
+                break;
+            case Cursor::ResizeWE:
+                cursor_type = GLFW_HRESIZE_CURSOR;
+                break;
+            case Cursor::ResizeNS:
+                cursor_type = GLFW_VRESIZE_CURSOR;
+                break;
+            case Cursor::Hand:
+                cursor_type = GLFW_HAND_CURSOR;
+                break;
+            default:
+                return;
+        }
+
+        _cursors[static_cast<UnsignedInt>(cursor)] = glfwCreateStandardCursor(cursor_type);
+    }
+}
+
+void GlfwApplication::setCursor(Cursor cursor) {
+    if(_cursors[static_cast<UnsignedInt>(cursor)])
+        glfwSetCursor(_window, _cursors[static_cast<UnsignedInt>(cursor)]);
+}
+
 bool GlfwApplication::tryCreate(const Configuration& configuration) {
     #ifdef MAGNUM_TARGET_GL
     #ifdef GLFW_NO_API
@@ -549,6 +585,8 @@ void GlfwApplication::setupCallbacks() {
 
 GlfwApplication::~GlfwApplication() {
     glfwDestroyWindow(_window);
+    for(auto& cursor: _cursors)
+        glfwDestroyCursor(cursor);
     glfwTerminate();
 }
 

src/Magnum/Platform/GlfwApplication.h

@@ -31,6 +31,7 @@
  */
 
 #include <string>
+#include <Corrade/Containers/Array.h>
 #include <Corrade/Containers/ArrayView.h>
 #include <Corrade/Containers/Optional.h>
 #include <Corrade/Containers/Pointer.h>
@@ -436,6 +437,33 @@ class GlfwApplication {
         /** @copydoc Sdl2Application::redraw() */
         void redraw() { _flags |= Flag::Redraw; }
 
+    public:
+        enum class Cursor : UnsignedInt {
+            Arrow,      /**< Arrow */
+            IBeam,      /**< I-Beam */
+            Crosshair,  /**< Crosshair */
+            ResizeWE,   /**< Double arrow pointing west and east */
+            ResizeNS,   /**< Double arrow pointing north and south */
+            Hand        /**< Hand */
+        };
+
+    public:
+        /**
+         * @brief Create a cursor that can then be used
+         * 
+         * @see @ref setCursor()
+         */
+        void createCursor(Cursor cursor);
+
+        /**
+         * @brief Set cursor
+         *
+         * The @p cursor is expected to be created from the @ref Configuration or
+         * with @ref createCursor().
+         * @see @ref createCursor()
+         */
+        void setCursor(Cursor cursor);
+
     private:
         /**
          * @brief Viewport event
@@ -577,6 +605,8 @@ class GlfwApplication {
 
         void setupCallbacks();
 
+        Containers::Array<GLFWcursor*> _cursors{static_cast<std::size_t>(Cursor::Hand)};
+
         /* These are saved from command-line arguments */
         bool _verboseLog{};
         Implementation::GlfwDpiScalingPolicy _commandLineDpiScalingPolicy{};

src/Magnum/Platform/Sdl2Application.cpp

@@ -275,6 +275,60 @@ void Sdl2Application::setWindowTitle(const std::string& title) {
     #endif
 }
 
+void Sdl2Application::createCursor(Cursor cursor) {
+    if(!_cursors[static_cast<UnsignedInt>(cursor)]) {
+        SDL_SystemCursor cursor_type;
+
+        switch(cursor) {
+            case Cursor::Arrow:
+                cursor_type = SDL_SYSTEM_CURSOR_ARROW;
+                break;
+            case Cursor::IBeam:
+                cursor_type = SDL_SYSTEM_CURSOR_IBEAM;
+                break;
+            case Cursor::Wait:
+                cursor_type = SDL_SYSTEM_CURSOR_WAIT;
+                break;
+            case Cursor::Crosshair:
+                cursor_type = SDL_SYSTEM_CURSOR_CROSSHAIR;
+                break;
+            case Cursor::WaitArrow:
+                cursor_type = SDL_SYSTEM_CURSOR_WAITARROW;
+                break;
+            case Cursor::ResizeNWSE:
+                cursor_type = SDL_SYSTEM_CURSOR_SIZENWSE;
+                break;
+            case Cursor::ResizeNESW:
+                cursor_type = SDL_SYSTEM_CURSOR_SIZENESW;
+                break;
+            case Cursor::ResizeWE:
+                cursor_type = SDL_SYSTEM_CURSOR_SIZEWE;
+                break;
+            case Cursor::ResizeNS:
+                cursor_type = SDL_SYSTEM_CURSOR_SIZENS;
+                break;
+            case Cursor::ResizeAll:
+                cursor_type = SDL_SYSTEM_CURSOR_SIZEALL;
+                break;
+            case Cursor::No:
+                cursor_type = SDL_SYSTEM_CURSOR_NO;
+                break;
+            case Cursor::Hand:
+                cursor_type = SDL_SYSTEM_CURSOR_HAND;
+                break;
+            default:
+                return;
+        }
+
+        _cursors[static_cast<UnsignedInt>(cursor)] = SDL_CreateSystemCursor(cursor_type);
+    }
+}
+
+void Sdl2Application::setCursor(Cursor cursor) {
+    if(_cursors[static_cast<UnsignedInt>(cursor)])
+        SDL_SetCursor(_cursors[static_cast<UnsignedInt>(cursor)]);
+}
+
 bool Sdl2Application::tryCreate(const Configuration& configuration) {
     #ifdef MAGNUM_TARGET_GL
     if(!(configuration.windowFlags() & Configuration::WindowFlag::Contextless))
@@ -684,6 +738,9 @@ Sdl2Application::~Sdl2Application() {
     #endif
     #endif
 
+    for(auto& cursor: _cursors)
+        SDL_FreeCursor(cursor);
+
     #ifndef CORRADE_TARGET_EMSCRIPTEN
     SDL_DestroyWindow(_window);
     #endif

src/Magnum/Platform/Sdl2Application.h

@@ -30,6 +30,7 @@
  */
 
 #include <string>
+#include <Corrade/Containers/Array.h>
 #include <Corrade/Containers/ArrayView.h>
 #include <Corrade/Containers/EnumSet.h>
 #include <Corrade/Containers/Pointer.h>
@@ -761,6 +762,39 @@ class Sdl2Application {
          */
         void redraw() { _flags |= Flag::Redraw; }
 
+    public:
+        enum class Cursor : UnsignedInt {
+            Arrow,      /**< Arrow */
+            IBeam,      /**< I-Beam */
+            Wait,       /**< Wait */
+            Crosshair,  /**< Crosshair */
+            WaitArrow,  /**< Small wait cursor */
+            ResizeNWSE, /**< Double arrow pointing northwest and southeast */
+            ResizeNESW, /**< Double arrow pointing northeast and southwest */
+            ResizeWE,   /**< Double arrow pointing west and east */
+            ResizeNS,   /**< Double arrow pointing north and south */
+            ResizeAll,  /**< Four pointed arrow pointing north, south, east, and west */
+            No,         /**< Slashed circle or crossbones */
+            Hand        /**< Hand */
+        };
+
+    public:
+        /**
+         * @brief Create a cursor that can then be used
+         * 
+         * @see @ref setCursor()
+         */
+        void createCursor(Cursor cursor);
+
+        /**
+         * @brief Set cursor
+         *
+         * The @p cursor is expected to be created from the @ref Configuration or
+         * with @ref createCursor().
+         * @see @ref createCursor()
+         */
+        void setCursor(Cursor cursor);
+
     private:
         /**
          * @brief Viewport event
@@ -1015,6 +1049,8 @@ class Sdl2Application {
         typedef Containers::EnumSet<Flag> Flags;
         CORRADE_ENUMSET_FRIEND_OPERATORS(Flags)
 
+        Containers::Array<SDL_Cursor*> _cursors{static_cast<std::size_t>(Cursor::Hand)};
+
         /* These are saved from command-line arguments */
         bool _verboseLog{};
         Implementation::Sdl2DpiScalingPolicy _commandLineDpiScalingPolicy{};