Merge pull request #13841 from Gymnasiast/fix/13236

Fix #13236: New ride type appears as new vehicle type in research

distribution/changelog.txt

@@ -22,6 +22,7 @@
 - Fix: [#9631, #10716] Banners drawing glitches when there are more than 32 on the screen at once.
 - Fix: [#12895] Mechanics are called to repair rides that have already been fixed.
 - Fix: [#13102] Underflow on height chart (Ride measurements).
+- Fix: [#13236] New ride type appears as new vehicle type in research.
 - Fix: [#13257] Rides that are exactly the minimum objective length are not counted.
 - Fix: [#13334] Uninitialised variables in CustomTabDesc.
 - Fix: [#13342] Rename tabChange to onTabChange in WindowDesc interface.

src/openrct2/management/Research.cpp

@@ -954,8 +954,6 @@ static void research_update_first_of_type(ResearchItem* researchItem)
 
     if (!_seenRideType[rideType])
         researchItem->flags |= RESEARCH_ENTRY_FLAG_FIRST_OF_TYPE;
-
-    _seenRideType[rideType] = true;
 }
 
 static void research_mark_ride_type_as_seen(const ResearchItem& researchItem)
@@ -989,7 +987,7 @@ void research_determine_first_of_type()
         if (gResearchLastItem.has_value() && !gResearchLastItem->IsNull() && researchItem.Equals(&gResearchLastItem.value()))
             continue;
 
-        // The next research item is also present in gResearchItemsInvented, even though it isn't invented yet(!)
+        // The next research item is (sometimes?) also present in gResearchItemsInvented, even though it isn't invented yet(!)
         if (gResearchNextItem.has_value() && !gResearchNextItem->IsNull() && researchItem.Equals(&gResearchNextItem.value()))
             continue;
 
@@ -1009,6 +1007,15 @@ void research_determine_first_of_type()
 
     for (auto& researchItem : gResearchItemsUninvented)
     {
+        // The next research item is (sometimes?) also present in gResearchItemsUninvented
+        if (gResearchNextItem.has_value() && !gResearchNextItem->IsNull() && researchItem.Equals(&gResearchNextItem.value()))
+        {
+            // Copy the "first of type" flag.
+            researchItem.flags = gResearchNextItem->flags;
+            continue;
+        }
+
         research_update_first_of_type(&researchItem);
+        research_mark_ride_type_as_seen(researchItem);
     }
 }