Platform Binding for GLFW updated with the release of GLFW 3.3 (#2547)

* With the release of GLFW 3.3, it is now possible to detect correctly monitors working area (see GLFW_HAS_MONITOR_WORK_AREA). GLFW 3.3 also introduced the window hint GLFW_FOCUS_ON_SHOW. This fixed the case where a new created window (viewport) takes the focus even if not visible.

* Disable a GLFW 3.2 windows hack when GLFW 3.3 is detected (related to window focused when shown).

examples/imgui_impl_glfw.cpp

@@ -44,12 +44,14 @@
 #define GLFW_EXPOSE_NATIVE_WIN32
 #include <GLFW/glfw3native.h>   // for glfwGetWin32Window
 #endif
-#define GLFW_HAS_WINDOW_TOPMOST     (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ GLFW_FLOATING
-#define GLFW_HAS_WINDOW_HOVERED     (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ GLFW_HOVERED
-#define GLFW_HAS_WINDOW_ALPHA       (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ glfwSetWindowOpacity
-#define GLFW_HAS_PER_MONITOR_DPI    (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ glfwGetMonitorContentScale
-#define GLFW_HAS_VULKAN             (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ glfwCreateWindowSurface
-#define GLFW_HAS_FOCUS_WINDOW       (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ glfwFocusWindow
+#define GLFW_HAS_WINDOW_TOPMOST       (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ GLFW_FLOATING
+#define GLFW_HAS_WINDOW_HOVERED       (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ GLFW_HOVERED
+#define GLFW_HAS_WINDOW_ALPHA         (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ glfwSetWindowOpacity
+#define GLFW_HAS_PER_MONITOR_DPI      (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ glfwGetMonitorContentScale
+#define GLFW_HAS_VULKAN               (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ glfwCreateWindowSurface
+#define GLFW_HAS_FOCUS_WINDOW         (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3200) // 3.2+ glfwFocusWindow
+#define GLFW_HAS_FOCUS_ON_SHOW        (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ GLFW_FOCUS_ON_SHOW
+#define GLFW_HAS_MONITOR_WORK_AREA    (GLFW_VERSION_MAJOR * 1000 + GLFW_VERSION_MINOR * 100 >= 3300) // 3.3+ glfwGetMonitorWorkarea
 
 // Data
 enum GlfwClientApi
@@ -428,8 +430,12 @@ static void ImGui_ImplGlfw_CreateWindow(ImGuiViewport* viewport)
     viewport->PlatformUserData = data;
 
     // GLFW 3.2 unfortunately always set focus on glfwCreateWindow() if GLFW_VISIBLE is set, regardless of GLFW_FOCUSED
+    // With GLFW 3.3, the hint GLFW_FOCUS_ON_SHOW fixes this problem
     glfwWindowHint(GLFW_VISIBLE, false);
     glfwWindowHint(GLFW_FOCUSED, false);
+#if GLFW_HAS_FOCUS_ON_SHOW
+     glfwWindowHint(GLFW_FOCUS_ON_SHOW, false);
+ #endif
     glfwWindowHint(GLFW_DECORATED, (viewport->Flags & ImGuiViewportFlags_NoDecoration) ? false : true);
 #if GLFW_HAS_WINDOW_TOPMOST
     glfwWindowHint(GLFW_FLOATING, (viewport->Flags & ImGuiViewportFlags_TopMost) ? true : false);
@@ -515,6 +521,7 @@ static void ImGui_ImplGlfw_ShowWindow(ImGuiViewport* viewport)
     ::SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR)WndProcNoInputs);
 #endif
 
+#if !GLFW_HAS_FOCUS_ON_SHOW
     // GLFW hack: GLFW 3.2 has a bug where glfwShowWindow() also activates/focus the window.
     // The fix was pushed to GLFW repository on 2018/01/09 and should be included in GLFW 3.3 via a GLFW_FOCUS_ON_SHOW window attribute.
     // See https://github.com/glfw/glfw/issues/1189
@@ -524,6 +531,7 @@ static void ImGui_ImplGlfw_ShowWindow(ImGuiViewport* viewport)
         ::ShowWindow(hwnd, SW_SHOWNA);
         return;
     }
+#endif
 #endif
 
     glfwShowWindow(data->Window);
@@ -678,8 +686,17 @@ static void ImGui_ImplGlfw_UpdateMonitors()
         int x, y;
         glfwGetMonitorPos(glfw_monitors[n], &x, &y);
         const GLFWvidmode* vid_mode = glfwGetVideoMode(glfw_monitors[n]);
+#if GLFW_HAS_MONITOR_WORK_AREA
+        monitor.MainPos = ImVec2((float)x, (float)y);
+        monitor.MainSize = ImVec2((float)vid_mode->width, (float)vid_mode->height);
+        int w, h;
+        glfwGetMonitorWorkarea(glfw_monitors[n], &x, &y, &w, &h);
+        monitor.WorkPos = ImVec2((float)x, (float)y);;
+        monitor.WorkSize = ImVec2((float)w, (float)h);
+#else
         monitor.MainPos = monitor.WorkPos = ImVec2((float)x, (float)y);
         monitor.MainSize = monitor.WorkSize = ImVec2((float)vid_mode->width, (float)vid_mode->height);
+#endif
 #if GLFW_HAS_PER_MONITOR_DPI
         // Warning: the validity of monitor DPI information on Windows depends on the application DPI awareness settings, which generally needs to be set in the manifest or at runtime.
         float x_scale, y_scale;