From 2ea0cb815d19c9b6197b075ed30fef6c1beae1d4 Mon Sep 17 00:00:00 2001
From: mlangkabel <malte.langkabel@gmail.com>
Date: Tue, 14 Jul 2026 20:50:43 +0200
Subject: [PATCH] fix issue where items on building's output port were not
 counted to output display in building panel

---
 src/ui/SelectedBuildingPanel.cpp | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/src/ui/SelectedBuildingPanel.cpp b/src/ui/SelectedBuildingPanel.cpp
index 1d6ca72..1e3ee73 100644
--- a/src/ui/SelectedBuildingPanel.cpp
+++ b/src/ui/SelectedBuildingPanel.cpp
@@ -479,13 +479,24 @@ void SelectedBuildingPanel::refreshBuffers(const Building* b)
         bufText += "\n";
     }
 
+    // Count output-side items: buffered plus still-emerging on the output belts.
+    // An emerging item still belongs to the output buffer (REQ-MAT-OUTPUT-EMERGE),
+    // so it must be included here or it would vanish from the panel while animating.
+    std::map<std::string, int> outCounts;
+    for (const Item& item : b->outputBuffer.items)
+    {
+        outCounts[item.type.id]++;
+    }
+    for (const std::vector<BeltItemSlot>& lane : b->emergingItems)
+    {
+        for (const BeltItemSlot& slot : lane)
+        {
+            outCounts[slot.item.type.id]++;
+        }
+    }
+
     if (recipe && !recipe->outputs.empty())
     {
-        std::map<std::string, int> outCounts;
-        for (const Item& item : b->outputBuffer.items)
-        {
-            outCounts[item.type.id]++;
-        }
         bufText += tr("Output: ");
         for (const RecipeOutput& out : recipe->outputs)
         {
@@ -497,13 +508,8 @@ void SelectedBuildingPanel::refreshBuffers(const Building* b)
                 + "/" + QString::number(out.amount) + "  ";
         }
     }
-    else if (!b->outputBuffer.items.empty())
+    else if (!outCounts.empty())
     {
-        std::map<std::string, int> outCounts;
-        for (const Item& item : b->outputBuffer.items)
-        {
-            outCounts[item.type.id]++;
-        }
         bufText += tr("Output: ");
         for (const std::pair<const std::string, int>& entry : outCounts)
         {