FlightIntegratorPerf optimizations replacing previous FlightPerf patch (#267)

* **FlightIntegratorPerf** : General micro-optimization of `FlightIntegrator` and `VesselPrecalculate`, components in charge of most of heavy lifting for newtonian physics as well as atmospheric and thermal physics.

* FlightIntegratorPerf : fixed various bugs in drag computation reimplementation.

---------

Co-authored-by: gotmachine <24925209+gotmachine@users.noreply.github.com>

Author: JonnyOThan

GameData/KSPCommunityFixes/Settings.cfg

@@ -451,9 +451,9 @@ KSP_COMMUNITY_FIXES
   // Various small performance patches (volume normalizer, eva module checks)
   MinorPerfTweaks = true
 
-  // General micro-optimization of FlightIntegrator and VesselPrecalculate, significantely increase
-  // framerate in large part count situations.
-  FlightPerf = true
+  // General micro-optimization of FlightIntegrator and VesselPrecalculate. This has a significant impact in
+  // large part count situations, and especially in atmospheric situations.
+  FlightIntegratorPerf = true
 
   // General micro-optimization of floating origin shifts. Main benefit is in large particle count situations
   // but this helps a bit in other cases as well.

KSPCommunityFixes/KSPCommunityFixes.cs

@@ -24,6 +24,8 @@ public class KSPCommunityFixes : MonoBehaviour
 
         public static KSPCommunityFixes Instance { get; private set; }
 
+        public static long FixedUpdateCount { get; private set; }
+
         private static string modPath;
         public static string ModPath
         {
@@ -125,5 +127,10 @@ public void MMPostLoadCallback()
                 BasePatch.Patch(patchesType);
             }
         }
+
+        void FixedUpdate()
+        {
+            FixedUpdateCount++;
+        }
     }
 }

KSPCommunityFixes/KSPCommunityFixes.csproj

@@ -172,7 +172,7 @@
     <Compile Include="Performance\DragCubeGeneration.cs" />
     <Compile Include="Performance\FasterPartFindTransform.cs" />
     <Compile Include="Performance\FastLoader.cs" />
-    <Compile Include="Performance\FlightPerf.cs" />
+    <Compile Include="Performance\FlightIntegratorPerf.cs" />
     <Compile Include="Performance\IMGUIOptimization.cs" />
     <Compile Include="Performance\LocalizerPerf.cs" />
     <Compile Include="Performance\LowerMinPhysicsDTPerFrame.cs" />