Merge 3ea97a242f into 65743b5647

src/Magnum/Platform/GlfwApplication.cpp

@@ -584,13 +584,27 @@ void GlfwApplication::setupCallbacks() {
     #ifdef MAGNUM_TARGET_GL
     glfwSetFramebufferSizeCallback(_window, [](GLFWwindow* const window, const int w, const int h) {
         auto& app = *static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window));
-        ViewportEvent e{app.windowSize(), {w, h}, app.dpiScaling()};
+        ViewportEvent e{ViewportEvent::Type::Resized, app.windowSize(), {w, h}, app.dpiScaling()};
         app.viewportEvent(e);
     });
     #else
     glfwSetWindowSizeCallback(_window, [](GLFWwindow* const window, const int w, const int h) {
         auto& app = *static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window));
-        ViewportEvent e{{w, h}, app.dpiScaling()};
+        ViewportEvent e{ViewportEvent::Type::Resized, {w, h}, app.dpiScaling()};
+        app.viewportEvent(e);
+    });
+    #endif
+    #if GLFW_VERSION_MAJOR*100 + GLFW_VERSION_MINOR >= 303
+    glfwSetWindowContentScaleCallback(_window, [](GLFWwindow* const window, float xScale, float yScale) {
+        auto& app = *static_cast<GlfwApplication*>(glfwGetWindowUserPointer(window));
+        ViewportEvent e{ViewportEvent::Type::DpiScalingChanged,
+            #ifdef MAGNUM_TARGET_GL
+            app.windowSize(), app.framebufferSize(),
+            #else
+            app.windowSize(),
+            #endif
+            /* Update the cached DPI scaling value as well */
+            app._dpiScaling = {xScale, yScale}};
         app.viewportEvent(e);
     });
     #endif

src/Magnum/Platform/GlfwApplication.h

@@ -1300,6 +1300,11 @@ class GlfwApplication::ExitEvent {
 */
 class GlfwApplication::ViewportEvent {
     public:
+        enum class Type: UnsignedByte {
+            Resized,
+            DpiScalingChanged
+        };
+
         /** @brief Copying is not allowed */
         ViewportEvent(const ViewportEvent&) = delete;
 
@@ -1312,6 +1317,9 @@ class GlfwApplication::ViewportEvent {
         /** @brief Moving is not allowed */
         ViewportEvent& operator=(ViewportEvent&&) = delete;
 
+        /** @brief Event type */
+        Type type() const { return _type; }
+
         /**
          * @brief Window size
          *
@@ -1353,16 +1361,17 @@ class GlfwApplication::ViewportEvent {
     private:
         friend GlfwApplication;
 
-        explicit ViewportEvent(const Vector2i& windowSize,
+        explicit ViewportEvent(Type type, const Vector2i& windowSize,
             #ifdef MAGNUM_TARGET_GL
             const Vector2i& framebufferSize,
             #endif
-            const Vector2& dpiScaling): _windowSize{windowSize},
+            const Vector2& dpiScaling): _type{type}, _windowSize{windowSize},
                 #ifdef MAGNUM_TARGET_GL
                 _framebufferSize{framebufferSize},
                 #endif
                 _dpiScaling{dpiScaling} {}
 
+        Type _type;
         const Vector2i _windowSize;
         #ifdef MAGNUM_TARGET_GL
         const Vector2i _framebufferSize;

src/Magnum/Platform/Sdl2Application.cpp

@@ -65,6 +65,8 @@
 #define WIN32_LEAN_AND_MEAN
 #endif
 #include <windows.h>
+/* For capturing the WM_DPICHANGED event */
+#include <SDL_syswm.h>
 #endif
 
 namespace Magnum { namespace Platform {
@@ -155,6 +157,11 @@ Sdl2Application::Sdl2Application(const Arguments& arguments, NoCreateT):
         std::exit(1);
     }
 
+    #ifdef CORRADE_TARGET_WINDOWS
+    /* Enable SysWM events to get the WM_DPICHANGED event on Windows */
+    SDL_EventState(SDL_SYSWMEVENT, SDL_ENABLE);
+    #endif
+
     /* Save command-line arguments */
     if(args.value("log") == "verbose") _verboseLog = true;
     const std::string dpiScaling = args.value("dpi-scaling");
@@ -834,7 +841,8 @@ bool Sdl2Application::mainLoopIteration() {
             _lastKnownCanvasSize = canvasSizei;
             const Vector2i size = _dpiScaling*canvasSizei;
             emscripten_set_canvas_element_size("#canvas", size.x(), size.y());
-            ViewportEvent e{
+            /** @todo dpi scaling changed? */
+            ViewportEvent e{ViewportEvent::Type::Resized,
                 #ifdef MAGNUM_TARGET_GL
                 size,
                 #endif
@@ -864,7 +872,7 @@ bool Sdl2Application::mainLoopIteration() {
                            framebuffer size and not window size on macOS, which
                            is weird. Query the values directly instead to be
                            really sure. */
-                        ViewportEvent e{event, windowSize(),
+                        ViewportEvent e{ViewportEvent::Type::Resized, event, windowSize(),
                             #ifdef MAGNUM_TARGET_GL
                             framebufferSize(),
                             #endif
@@ -942,6 +950,21 @@ bool Sdl2Application::mainLoopIteration() {
                 }
             } break;
 
+            #ifdef CORRADE_TARGET_WINDOWS
+            case SDL_SYSWMEVENT: {
+                if(event.syswm.msg->msg.win.msg == WM_DPICHANGED) {
+                    DWORD dpi = event.syswm.msg->msg.win.wParam;
+                    ViewportEvent e{ViewportEvent::Type::DpiScalingChanged, event, windowSize(),
+                        #ifdef MAGNUM_TARGET_GL
+                        framebufferSize(),
+                        #endif
+                        /* Update the cached DPI scaling value as well */
+                        _dpiScaling = Vector2{Vector2i{LOWORD(dpi), HIWORD(dpi)}}/96.0f};
+                    viewportEvent(e);
+                }
+            } break;
+            #endif
+
             /* Direct everything else to anyEvent(), so users can implement
                event handling for things not present in the Application APIs */
             default: if(!(_flags & Flag::NoAnyEvent)) anyEvent(event);

src/Magnum/Platform/Sdl2Application.h

@@ -1829,6 +1829,11 @@ class Sdl2Application::ExitEvent {
 */
 class Sdl2Application::ViewportEvent {
     public:
+        enum class Type: UnsignedByte {
+            Resized,
+            DpiScalingChanged
+        };
+
         /** @brief Copying is not allowed */
         ViewportEvent(const ViewportEvent&) = delete;
 
@@ -1841,6 +1846,9 @@ class Sdl2Application::ViewportEvent {
         /** @brief Moving is not allowed */
         ViewportEvent& operator=(ViewportEvent&&) = delete;
 
+        /** @brief Event type */
+        Type type() const { return _type; }
+
         /**
          * @brief Window size
          *
@@ -1893,7 +1901,7 @@ class Sdl2Application::ViewportEvent {
     private:
         friend Sdl2Application;
 
-        explicit ViewportEvent(
+        explicit ViewportEvent(Type type,
             #ifndef CORRADE_TARGET_EMSCRIPTEN
             const SDL_Event& event,
             #endif
@@ -1901,7 +1909,7 @@ class Sdl2Application::ViewportEvent {
             #ifdef MAGNUM_TARGET_GL
             const Vector2i& framebufferSize,
             #endif
-            const Vector2& dpiScaling):
+            const Vector2& dpiScaling): _type{type},
                 #ifndef CORRADE_TARGET_EMSCRIPTEN
                 _event(event),
                 #endif
@@ -1911,6 +1919,7 @@ class Sdl2Application::ViewportEvent {
                 #endif
                 _dpiScaling{dpiScaling} {}
 
+        Type _type;
         #ifndef CORRADE_TARGET_EMSCRIPTEN
         const SDL_Event& _event;
         #endif

src/Magnum/Platform/Test/GlfwApplicationTest.cpp

@@ -47,6 +47,11 @@ struct GlfwApplicationTest: Platform::Application {
             << event.framebufferSize()
             #endif
             << event.dpiScaling();
+
+        if(event.type() == ViewportEvent::Type::DpiScalingChanged) {
+            Debug{} << "DPI scaling changed, resizing to" << _lastUnscaledWindowSize;
+            setWindowSize(_lastUnscaledWindowSize);
+        } else _lastUnscaledWindowSize = event.windowSize()/event.dpiScaling();
     }
 
     void keyPressEvent(KeyEvent& event) override {
@@ -96,6 +101,9 @@ struct GlfwApplicationTest: Platform::Application {
     }
 
     void drawEvent() override {}
+
+    private:
+        Vector2i _lastUnscaledWindowSize;
 };
 
 GlfwApplicationTest::GlfwApplicationTest(const Arguments& arguments): Platform::Application{arguments, NoCreate} {
@@ -116,6 +124,10 @@ GlfwApplicationTest::GlfwApplicationTest(const Arguments& arguments): Platform::
         #endif
         << dpiScaling();
 
+    /* Save desired window size for resizing when going between differently
+       dense displays */
+    _lastUnscaledWindowSize = windowSize()/dpiScaling();
+
     #if GLFW_VERSION_MAJOR*100 + GLFW_VERSION_MINOR >= 302
     Utility::Resource rs{"icons"};
     PluginManager::Manager<Trade::AbstractImporter> manager;

src/Magnum/Platform/Test/Sdl2ApplicationTest.cpp

@@ -66,6 +66,11 @@ struct Sdl2ApplicationTest: Platform::Application {
             << event.framebufferSize()
             #endif
             << event.dpiScaling();
+
+        if(event.type() == ViewportEvent::Type::DpiScalingChanged) {
+            Debug{} << "DPI scaling changed, resizing to" << _lastUnscaledWindowSize;
+            setWindowSize(_lastUnscaledWindowSize);
+        } else _lastUnscaledWindowSize = event.windowSize()/event.dpiScaling();
     }
 
     /* For testing event coordinates */
@@ -137,10 +142,12 @@ struct Sdl2ApplicationTest: Platform::Application {
         if(event.type == SDL_WINDOWEVENT) d << event.window.event;
     }
 
-    #ifdef CORRADE_TARGET_EMSCRIPTEN
     private:
+        #ifdef CORRADE_TARGET_EMSCRIPTEN
         bool _fullscreen = false;
-    #endif
+        #else
+        Vector2i _lastUnscaledWindowSize;
+        #endif
 };
 
 Sdl2ApplicationTest::Sdl2ApplicationTest(const Arguments& arguments): Platform::Application{arguments, NoCreate} {
@@ -162,6 +169,10 @@ Sdl2ApplicationTest::Sdl2ApplicationTest(const Arguments& arguments): Platform::
         #endif
         << dpiScaling();
 
+    /* Save desired window size for resizing when going between differently
+       dense displays */
+    _lastUnscaledWindowSize = windowSize()/dpiScaling();
+
     #ifndef CORRADE_TARGET_EMSCRIPTEN
     #if SDL_MAJOR_VERSION*1000 + SDL_MINOR_VERSION*100 + SDL_PATCHLEVEL >= 2005
     Utility::Resource rs{"icons"};