NewFrame: Allow MovedWindow setting the ImGuiWindowFlags_NoInputs after moving has started in order to be able to detect windows below it, which is useful for e.g. docking mechanisms.

imgui.cpp

@@ -2361,8 +2361,11 @@ void ImGui::NewFrame()
             SaveIniSettingsToDisk(g.IO.IniFilename);
     }
 
-    // Find the window we are hovering. Child windows can extend beyond the limit of their parent so we need to derive HoveredRootWindow from HoveredWindow
-    g.HoveredWindow = g.MovingWindow ? g.MovingWindow : FindHoveredWindow(g.IO.MousePos);
+    // Find the window we are hovering
+    // - Child windows can extend beyond the limit of their parent so we need to derive HoveredRootWindow from HoveredWindow.
+    // - When moving a window we can skip the search, which also conveniently bypasses the fact that window->WindowRectClipped is lagging as this point.
+    // - We also support the moved window toggling the NoInputs flag after moving has started in order to be able to detect windows below it, which is useful for e.g. docking mechanisms.
+    g.HoveredWindow = (g.MovingWindow && !(g.MovingWindow->Flags & ImGuiWindowFlags_NoInputs)) ? g.MovingWindow : FindHoveredWindow(g.IO.MousePos);
     g.HoveredRootWindow = g.HoveredWindow ? g.HoveredWindow->RootWindow : NULL;
 
     if (ImGuiWindow* modal_window = GetFrontMostModalRootWindow())

imgui.h

@@ -502,7 +502,7 @@ enum ImGuiWindowFlags_
     ImGuiWindowFlags_AlwaysAutoResize       = 1 << 6,   // Resize every window to its content every frame
     ImGuiWindowFlags_ShowBorders            = 1 << 7,   // Show borders around windows and items
     ImGuiWindowFlags_NoSavedSettings        = 1 << 8,   // Never load/save settings in .ini file
-    ImGuiWindowFlags_NoInputs               = 1 << 9,   // Disable catching mouse or keyboard inputs
+    ImGuiWindowFlags_NoInputs               = 1 << 9,   // Disable catching mouse or keyboard inputs, hovering test with pass through.
     ImGuiWindowFlags_MenuBar                = 1 << 10,  // Has a menu-bar
     ImGuiWindowFlags_HorizontalScrollbar    = 1 << 11,  // Allow horizontal scrollbar to appear (off by default). You may use SetNextWindowContentSize(ImVec2(width,0.0f)); prior to calling Begin() to specify width. Read code in imgui_demo in the "Horizontal Scrolling" section.
     ImGuiWindowFlags_NoFocusOnAppearing     = 1 << 12,  // Disable taking focus when transitioning from hidden to visible state