Internals: Clarified internal storage for RootWindow with specific semantic (the Docking branch will need to introduce finer differenciation there.)

imgui.cpp

@@ -1938,9 +1938,10 @@ ImGuiWindow::ImGuiWindow(ImGuiContext* context, const char* name)
     DrawList->_OwnerName = Name;
     ParentWindow = NULL;
     RootWindow = NULL;
-    RootNonPopupWindow = NULL;
+    RootWindowForTitleBarHighlight = NULL;
+    RootWindowForTabbing = NULL;
+    RootWindowForNav = NULL;
 
-    NavRootWindow = NULL;
     NavLastIds[0] = NavLastIds[1] = 0;
     NavRectRel[0] = NavRectRel[1] = ImRect();
     NavLastChildNavWindow = NULL;
@@ -2408,7 +2409,7 @@ bool ImGui::ItemAdd(const ImRect& bb, ImGuiID id, const ImRect* nav_bb_arg)
         //      We could early out with "if (is_clipped && !g.NavInitRequest) return false;" but when we wouldn't be able to reach unclipped widgets. This would work if user had explicit scrolling control (e.g. mapped on a stick)
         window->DC.NavLayerActiveMaskNext |= window->DC.NavLayerCurrentMask;
         if (g.NavId == id || g.NavAnyRequest)
-            if (g.NavWindow->NavRootWindow == window->NavRootWindow)
+            if (g.NavWindow->RootWindowForNav == window->RootWindowForNav)
                 if (window == g.NavWindow || ((window->Flags | g.NavWindow->Flags) & ImGuiWindowFlags_NavFlattened))
                     NavProcessItem(window, nav_bb_arg ? *nav_bb_arg : bb, id);
     }
@@ -2808,7 +2809,7 @@ static void ImGui::NavUpdateWindowing()
     if (start_windowing_with_gamepad || start_windowing_with_keyboard)
         if (ImGuiWindow* window = g.NavWindow ? g.NavWindow : FindWindowNavigable(g.Windows.Size - 1, -INT_MAX, -1))
         {
-            g.NavWindowingTarget = window->RootNonPopupWindow;
+            g.NavWindowingTarget = window->RootWindowForTabbing;
             g.NavWindowingHighlightTimer = g.NavWindowingHighlightAlpha = 0.0f;
             g.NavWindowingToggleLayer = start_windowing_with_keyboard ? false : true;
             g.NavWindowingInputSource = start_windowing_with_keyboard ? ImGuiInputSource_NavKeyboard : ImGuiInputSource_NavGamepad;
@@ -2877,7 +2878,7 @@ static void ImGui::NavUpdateWindowing()
     }
 
     // Apply final focus
-    if (apply_focus_window && (g.NavWindow == NULL || apply_focus_window != g.NavWindow->RootNonPopupWindow))
+    if (apply_focus_window && (g.NavWindow == NULL || apply_focus_window != g.NavWindow->RootWindowForTabbing))
     {
         g.NavDisableHighlight = false;
         g.NavDisableMouseHover = true;
@@ -5659,14 +5660,13 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
 
         // Initialize
         window->ParentWindow = parent_window;
-        window->RootWindow = window->RootNonPopupWindow = window;
+        window->RootWindow = window->RootWindowForTitleBarHighlight = window->RootWindowForTabbing = window->RootWindowForNav = window;
         if (parent_window && (flags & ImGuiWindowFlags_ChildWindow) && !window_is_child_tooltip)
             window->RootWindow = parent_window->RootWindow;
         if (parent_window && !(flags & ImGuiWindowFlags_Modal) && (flags & (ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_Popup)))
-            window->RootNonPopupWindow = parent_window->RootNonPopupWindow;
-        window->NavRootWindow = window;
-        while (window->NavRootWindow->Flags & ImGuiWindowFlags_NavFlattened)
-            window->NavRootWindow = window->NavRootWindow->ParentWindow;
+            window->RootWindowForTitleBarHighlight = window->RootWindowForTabbing = parent_window->RootWindowForTitleBarHighlight; // Same value in master branch, will differ for docking
+        while (window->RootWindowForNav->Flags & ImGuiWindowFlags_NavFlattened)
+            window->RootWindowForNav = window->RootWindowForNav->ParentWindow;
 
         window->Active = true;
         window->BeginOrderWithinParent = 0;
@@ -5894,14 +5894,14 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
         // Draw window + handle manual resize
         const float window_rounding = window->WindowRounding;
         const float window_border_size = window->WindowBorderSize;
-        ImRect title_bar_rect = window->TitleBarRect();
-        const bool window_is_focused = want_focus || (g.NavWindow && window->RootNonPopupWindow == g.NavWindow->RootNonPopupWindow);
+        const bool title_bar_is_highlight = want_focus || (g.NavWindow && window->RootWindowForTitleBarHighlight == g.NavWindow->RootWindowForTitleBarHighlight);
+        const ImRect title_bar_rect = window->TitleBarRect();
         if (window->Collapsed)
         {
             // Title bar only
             float backup_border_size = style.FrameBorderSize;
             g.Style.FrameBorderSize = window->WindowBorderSize;
-            ImU32 title_bar_col = GetColorU32((window_is_focused && !g.NavDisableHighlight) ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBgCollapsed);
+            ImU32 title_bar_col = GetColorU32((title_bar_is_highlight && !g.NavDisableHighlight) ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBgCollapsed);
             RenderFrame(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, true, window_rounding);
             g.Style.FrameBorderSize = backup_border_size;
         }
@@ -5917,7 +5917,7 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
             window->DrawList->AddRectFilled(window->Pos+ImVec2(0,window->TitleBarHeight()), window->Pos+window->Size, bg_col, window_rounding, (flags & ImGuiWindowFlags_NoTitleBar) ? ImDrawCornerFlags_All : ImDrawCornerFlags_Bot);
 
             // Title bar
-            ImU32 title_bar_col = GetColorU32(window->Collapsed ? ImGuiCol_TitleBgCollapsed : window_is_focused ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBg);
+            ImU32 title_bar_col = GetColorU32(window->Collapsed ? ImGuiCol_TitleBgCollapsed : title_bar_is_highlight ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBg);
             if (!(flags & ImGuiWindowFlags_NoTitleBar))
                 window->DrawList->AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, window_rounding, ImDrawCornerFlags_Top);
 
@@ -6753,7 +6753,7 @@ bool ImGui::IsWindowFocused(ImGuiFocusedFlags flags)
 bool ImGui::IsWindowNavFocusable(ImGuiWindow* window)
 {
     ImGuiContext& g = *GImGui;
-    return window->Active && window == window->RootNonPopupWindow && (!(window->Flags & ImGuiWindowFlags_NoNavFocus) || window == g.NavWindow);
+    return window->Active && window == window->RootWindowForTabbing && (!(window->Flags & ImGuiWindowFlags_NoNavFocus) || window == g.NavWindow);
 }
 
 float ImGui::GetWindowWidth()
@@ -7198,7 +7198,7 @@ void ImGui::SetItemDefaultFocus()
     ImGuiWindow* window = g.CurrentWindow;
     if (!window->Appearing)
         return;
-    if (g.NavWindow == window->NavRootWindow && (g.NavInitRequest || g.NavInitResultId != 0) && g.NavLayer == g.NavWindow->DC.NavLayerCurrent)
+    if (g.NavWindow == window->RootWindowForNav && (g.NavInitRequest || g.NavInitResultId != 0) && g.NavLayer == g.NavWindow->DC.NavLayerCurrent)
     {
         g.NavInitRequest = false;
         g.NavInitResultId = g.NavWindow->DC.LastItemId;

imgui_internal.h

@@ -957,10 +957,11 @@ struct IMGUI_API ImGuiWindow
     float                   FontWindowScale;                    // Scale multiplier per-window
     ImDrawList*             DrawList;
     ImGuiWindow*            ParentWindow;                       // If we are a child _or_ popup window, this is pointing to our parent. Otherwise NULL.
-    ImGuiWindow*            RootWindow;                         // Generally point to ourself. If we are a child window, this is pointing to the first non-child parent window.
-    ImGuiWindow*            RootNonPopupWindow;                 // Generally point to ourself. Used to display TitleBgActive color and for selecting which window to use for NavWindowing
+    ImGuiWindow*            RootWindow;                         // Point to ourself or first ancestor that is not a child window.
+    ImGuiWindow*            RootWindowForTitleBarHighlight;     // Point to ourself or first ancestor which will display TitleBgActive color when this window is active.
+    ImGuiWindow*            RootWindowForTabbing;               // Point to ourself or first ancestor which can be CTRL-Tabbed into.
+    ImGuiWindow*            RootWindowForNav;                   // Point to ourself or first ancestor which doesn't have the NavFlattened flag.
 
-    ImGuiWindow*            NavRootWindow;                      // Generally point to ourself. If we are a child window with the NavFlattened flag, point to a parent window. 
     ImGuiWindow*            NavLastChildNavWindow;              // When going to the menu bar, we remember the child window we came from. (This could probably be made implicit if we kept g.Windows sorted by last focused including child window.)
     ImGuiID                 NavLastIds[2];                      // Last known NavId for this window, per layer (0/1)
     ImRect                  NavRectRel[2];                      // Reference rectangle, in window relative space