From 762ec445e63a95c1545b18b28d528f8ce38a9afd Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Mon, 28 Aug 2023 11:24:29 +0200
Subject: [PATCH] Docking: Fixed bad bug, dock node host wouldn't merge
 background. (#6753, #6716)

Fixes f422e78. Didn't crash because g.Windows[] is always larger than g.WindowsFocusOrder[].
---
 imgui.cpp | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/imgui.cpp b/imgui.cpp
index 7bce4e4c..059d8c37 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -5341,20 +5341,16 @@ void ImGui::Render()
     CallContextHooks(&g, ImGuiContextHookType_RenderPre);
 
     // Add background ImDrawList (for each active viewport)
-    for (int n = 0; n != g.Viewports.Size; n++)
+    for (ImGuiViewportP* viewport : g.Viewports)
     {
-        ImGuiViewportP* viewport = g.Viewports[n];
         InitViewportDrawData(viewport);
         if (viewport->BgFgDrawLists[0] != NULL)
             AddDrawListToDrawDataEx(&viewport->DrawDataP, viewport->DrawDataBuilder.Layers[0], GetBackgroundDrawList(viewport));
     }
 
-    for (int n = 0; n != g.WindowsFocusOrder.Size; n++)
-    {
-        ImGuiWindow* window = g.Windows[n];
+    for (ImGuiWindow* window : g.WindowsFocusOrder)
         if (window->Flags & ImGuiWindowFlags_DockNodeHost)
             window->DrawList->ChannelsMerge();
-    }
 
     // Draw modal/window whitening backgrounds
     RenderDimmedBackgrounds();