Viewport: Renamed member + added note about a Docking issue with restoring focus.

imgui.cpp

@@ -6260,6 +6260,10 @@ void ImGui::FocusPreviousWindowIgnoringOne(ImGuiWindow* ignore_window)
         if (window != ignore_window && window->WasActive && !(window->Flags & ImGuiWindowFlags_ChildWindow))
             if ((window->Flags & (ImGuiWindowFlags_NoMouseInputs | ImGuiWindowFlags_NoNavInputs)) != (ImGuiWindowFlags_NoMouseInputs | ImGuiWindowFlags_NoNavInputs))
             {
+                // FIXME-DOCKING: This is failing (lagging by one frame) for docked windows. 
+                // If A and B are docked into window and B disappear, at the NewFrame() call site window->NavLastChildNavWindow will still point to B.
+                // We might leverage the tab order implicitly stored in window->DockNodeAsHost->TabBar (essentially the 'most_recently_selected_tab' code in tab bar will do that but on next update)
+                // to tell which is the "previous" window. Or we may leverage 'LastFrameFocused/LastFrameJustFocused' and have this function handle child window itself?
                 ImGuiWindow* focus_window = NavRestoreLastChildNavWindow(window);
                 FocusWindow(focus_window);
                 return;
@@ -10554,8 +10558,8 @@ void ImGui::UpdatePlatformWindows()
 
             // Even without focus, we assume the window becomes front-most. 
             // This is useful for our platform z-order heuristic when io.MouseHoveredViewport is not available.
-            if (viewport->LastFrontMostStampCount != g.WindowsFrontMostStampCount)
+            if (viewport->LastFrontMostStampCount != g.ViewportFrontMostStampCount)
-                viewport->LastFrontMostStampCount = ++g.WindowsFrontMostStampCount;
+                viewport->LastFrontMostStampCount = ++g.ViewportFrontMostStampCount;
         }
 
         // Clear request flags
@@ -10576,8 +10580,8 @@ void ImGui::UpdatePlatformWindows()
         }
         if (focused_viewport && g.PlatformLastFocusedViewport != focused_viewport->ID)
         {
-            if (focused_viewport->LastFrontMostStampCount != g.WindowsFrontMostStampCount)
+            if (focused_viewport->LastFrontMostStampCount != g.ViewportFrontMostStampCount)
-                focused_viewport->LastFrontMostStampCount = ++g.WindowsFrontMostStampCount;
+                focused_viewport->LastFrontMostStampCount = ++g.ViewportFrontMostStampCount;
             g.PlatformLastFocusedViewport = focused_viewport->ID;
         }
     }

imgui_internal.h

@@ -951,7 +951,6 @@ struct ImGuiContext
     ImVector<ImGuiWindow*>  CurrentWindowStack;
     ImGuiStorage            WindowsById;
     int                     WindowsActiveCount;
-    int                     WindowsFrontMostStampCount;         // Every time the front-most window changes, we stamp its viewport with an incrementing counter
     ImGuiWindow*            CurrentWindow;                      // Being drawn into
     ImGuiWindow*            HoveredWindow;                      // Will catch mouse inputs
     ImGuiWindow*            HoveredRootWindow;                  // Will catch mouse inputs (for focus/move only)
@@ -996,6 +995,7 @@ struct ImGuiContext
     ImGuiViewportP*         MouseViewport;
     ImGuiViewportP*         MouseLastHoveredViewport;           // Last known viewport that was hovered by mouse (even if we are not hovering any viewport any more) + honoring the _NoInputs flag.
     ImGuiID                 PlatformLastFocusedViewport;        // Record of last focused platform window/viewport, when this changes we stamp the viewport as front-most
+    int                     ViewportFrontMostStampCount;        // Every time the front-most window changes, we stamp its viewport with an incrementing counter
 
     // Navigation data (for gamepad/keyboard)
     ImGuiWindow*            NavWindow;                          // Focused window for navigation. Could be called 'FocusWindow'
@@ -1141,7 +1141,6 @@ struct ImGuiContext
         FrameCount = 0;
         FrameCountEnded = FrameCountPlatformEnded = FrameCountRendered = -1;
         WindowsActiveCount = 0;
-        WindowsFrontMostStampCount = 0;
         CurrentWindow = NULL;
         HoveredWindow = NULL;
         HoveredRootWindow = NULL;
@@ -1175,6 +1174,7 @@ struct ImGuiContext
         CurrentViewport = NULL;
         MouseViewport = MouseLastHoveredViewport = NULL;
         PlatformLastFocusedViewport = 0;
+        ViewportFrontMostStampCount = 0;
 
         NavWindow = NULL;
         NavId = NavActivateId = NavActivateDownId = NavActivatePressedId = NavInputId = 0;