Platform: setup GlfwApplication callbacks in a central place.

Removes all needless private static class members and fixes a bug
introduced when getting rid of the global window pointer -- the user
window pointer was set only in the case of having a GL context, not in
the contextless case. Boom. (This bug happened after 2018.04, so I'm not
putting that in the changelog.)

src/Magnum/Platform/GlfwApplication.cpp

@@ -64,7 +64,9 @@ GlfwApplication::GlfwApplication(const Arguments& arguments, NoCreateT):
     #endif
 {
     /* Init GLFW */
-    glfwSetErrorCallback(staticErrorCallback);
+    glfwSetErrorCallback([](int, const char* const description) {
+        Error{} << description;
+    });
 
     if(!glfwInit()) {
         Error() << "Could not initialize GLFW";
@@ -138,12 +140,7 @@ bool GlfwApplication::tryCreate(const Configuration& configuration) {
     glfwSetInputMode(_window, GLFW_CURSOR, Int(configuration.cursorMode()));
 
     /* Set callbacks */
-    glfwSetFramebufferSizeCallback(_window, staticViewportEvent);
+    setupCallbacks();
-    glfwSetKeyCallback(_window, staticKeyEvent);
-    glfwSetCursorPosCallback(_window, staticMouseMoveEvent);
-    glfwSetMouseButtonCallback(_window, staticMouseEvent);
-    glfwSetScrollCallback(_window, staticMouseScrollEvent);
-    glfwSetCharCallback(_window, staticTextInputEvent);
 
     return true;
 }
@@ -325,13 +322,7 @@ bool GlfwApplication::tryCreate(const Configuration& configuration, const GLConf
     glfwSetInputMode(_window, GLFW_CURSOR, Int(configuration.cursorMode()));
 
     /* Set callbacks */
-    glfwSetWindowUserPointer(_window, this);
+    setupCallbacks();
-    glfwSetFramebufferSizeCallback(_window, staticViewportEvent);
-    glfwSetKeyCallback(_window, staticKeyEvent);
-    glfwSetCursorPosCallback(_window, staticMouseMoveEvent);
-    glfwSetMouseButtonCallback(_window, staticMouseEvent);
-    glfwSetScrollCallback(_window, staticMouseScrollEvent);
-    glfwSetCharCallback(_window, staticTextInputEvent);
 
     /* Make the final context current */
     glfwMakeContextCurrent(_window);
@@ -351,37 +342,12 @@ bool GlfwApplication::tryCreate(const Configuration& configuration, const GLConf
 }
 #endif
 
-GlfwApplication::~GlfwApplication() {
+void GlfwApplication::setupCallbacks() {
-    glfwDestroyWindow(_window);
+    glfwSetWindowUserPointer(_window, this);
-    glfwTerminate();
+    glfwSetFramebufferSizeCallback(_window, [](GLFWwindow* const window, const int w, const int h) {
-}
-
-Vector2i GlfwApplication::windowSize() {
-    Vector2i size;
-    glfwGetWindowSize(_window, &size.x(), &size.y());
-    return size;
-}
-
-void GlfwApplication::setSwapInterval(const Int interval) {
-    glfwSwapInterval(interval);
-}
-
-int GlfwApplication::exec() {
-    while(!glfwWindowShouldClose(_window)) {
-        if(_flags & Flag::Redraw) {
-            _flags &= ~Flag::Redraw;
-            drawEvent();
-        }
-        glfwPollEvents();
-    }
-    return 0;
-}
-
-void GlfwApplication::staticViewportEvent(GLFWwindow* const window, const int w, const int h) {
         static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window))->viewportEvent({w, h});
-}
+    });
-
+    glfwSetKeyCallback(_window, [](GLFWwindow* const window, const int key, int, const int action, const int mods) {
-void GlfwApplication::staticKeyEvent(GLFWwindow* const window, const int key, int, const int action, const int mods) {
         const auto instance = static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window));
 
         KeyEvent e(static_cast<KeyEvent::Key>(key), {static_cast<InputEvent::Modifier>(mods)}, action == GLFW_REPEAT);
@@ -393,33 +359,8 @@ void GlfwApplication::staticKeyEvent(GLFWwindow* const window, const int key, in
         } else if(action == GLFW_REPEAT) {
             instance->keyPressEvent(e);
         }
-}
+    });
-
+    glfwSetMouseButtonCallback(_window, [](GLFWwindow* const window, const int button, const int action, const int mods) {
-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;
-}
-
-auto GlfwApplication::MouseScrollEvent::modifiers() -> Modifiers {
-    if(!_modifiers) _modifiers = currentGlfwModifiers(_window);
-    return *_modifiers;
-}
-
-void GlfwApplication::staticMouseEvent(GLFWwindow* window, int button, int action, int mods) {
         const auto instance = static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window));
 
         double x, y;
@@ -431,14 +372,12 @@ void GlfwApplication::staticMouseEvent(GLFWwindow* window, int button, int actio
         } else if(action == GLFW_RELEASE) {
             instance->mouseReleaseEvent(e);
         } /* we don't handle GLFW_REPEAT */
-}
+    });
-
+    glfwSetCursorPosCallback(_window, [](GLFWwindow* const window, const double x, const double y) {
-void GlfwApplication::staticMouseMoveEvent(GLFWwindow* window, double x, double y) {
         MouseMoveEvent e{window, Vector2i{Int(x), Int(y)}};
         static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window))->mouseMoveEvent(e);
-}
+    });
-
+    glfwSetScrollCallback(_window, [](GLFWwindow* window, double xoffset, double yoffset) {
-void GlfwApplication::staticMouseScrollEvent(GLFWwindow* window, double xoffset, double yoffset) {
         const auto instance = static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window));
 
         MouseScrollEvent e(window, Vector2{Float(xoffset), Float(yoffset)});
@@ -457,9 +396,8 @@ void GlfwApplication::staticMouseScrollEvent(GLFWwindow* window, double xoffset,
             instance->mousePressEvent(e1);
         }
         #endif
-}
+    });
-
+    glfwSetCharCallback(_window, [](GLFWwindow* window, unsigned int codepoint) {
-void GlfwApplication::staticTextInputEvent(GLFWwindow* window, unsigned int codepoint) {
         const auto instance = static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window));
 
         if(!(instance->_flags & Flag::TextInputActive)) return;
@@ -468,10 +406,57 @@ void GlfwApplication::staticTextInputEvent(GLFWwindow* window, unsigned int code
         const std::size_t size = Utility::Unicode::utf8(codepoint, utf8);
         TextInputEvent e{{utf8, size}};
         instance->textInputEvent(e);
+    });
+}
+
+GlfwApplication::~GlfwApplication() {
+    glfwDestroyWindow(_window);
+    glfwTerminate();
+}
+
+Vector2i GlfwApplication::windowSize() {
+    Vector2i size;
+    glfwGetWindowSize(_window, &size.x(), &size.y());
+    return size;
+}
+
+void GlfwApplication::setSwapInterval(const Int interval) {
+    glfwSwapInterval(interval);
 }
 
-void GlfwApplication::staticErrorCallback(int, const char* description) {
+int GlfwApplication::exec() {
-    Error() << description;
+    while(!glfwWindowShouldClose(_window)) {
+        if(_flags & Flag::Redraw) {
+            _flags &= ~Flag::Redraw;
+            drawEvent();
+        }
+        glfwPollEvents();
+    }
+    return 0;
+}
+
+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;
+}
+
+auto GlfwApplication::MouseScrollEvent::modifiers() -> Modifiers {
+    if(!_modifiers) _modifiers = currentGlfwModifiers(_window);
+    return *_modifiers;
 }
 
 void GlfwApplication::viewportEvent(const Vector2i&) {}

src/Magnum/Platform/GlfwApplication.h

@@ -467,14 +467,7 @@ class GlfwApplication {
         typedef Containers::EnumSet<Flag> Flags;
         CORRADE_ENUMSET_FRIEND_OPERATORS(Flags)
 
-        static void staticErrorCallback(int error, const char* description);
+        void setupCallbacks();
-
-        static void staticViewportEvent(GLFWwindow* window, int w, int h);
-        static void staticKeyEvent(GLFWwindow* window, int key, int scancode, int action, int mod);
-        static void staticMouseEvent(GLFWwindow* window, int button, int action, int mods);
-        static void staticMouseMoveEvent(GLFWwindow* window, double x, double y);
-        static void staticMouseScrollEvent(GLFWwindow* window, double xoffset, double yoffset);
-        static void staticTextInputEvent(GLFWwindow* window, unsigned int codepoint);
 
         GLFWwindow* _window{nullptr};
         Flags _flags;