Loading optimizations (#269)

Various loading performance focused changes, part of the general loading re-implementation :
- Added performance metrics logging upon reaching the main menu
- Added (almost) entirely custom MU model parser, roughly 3 times the throughput of the stock parser (~300 MB/s on my machine). Will only really benefit to people having fast NVME drives with good random read performance.
- KSPCF now maintains dictionaries of loaded models and texture assets by their url/name, and patch the stock `GameDatabase.GetModel*` / `GameDatabase.GetTexture*` method to use them instead of doing a linear search.
  This was especially bad with models, as the method would compare the requested string to the `GameObject.name` property for every model in the database.
  Unfortunately, we have no way to know if additional assets are loaded by custom means, so we have to fallback to a linear search when the requested texture isn't known and we can't assume that a texture that isn't found at some point won't be found in the future, so in cases where a not loaded / absent texture is queried, there is no performance improvement.
  Overall, this benefit to many scenarios, during initial loading for model parsing and part compilation, and more marginally for scenes switches [when various initialization paths are re-acquiring a texture reference](https://github.com/search?q=GameDatabase.Instance.GetTexture+OR+GameDatabase.Instance.GetModel+language%3AC%23&type=code).

Other changes, also loading related :
- As a part of the `MinorPerfTweaks` patch, patched the `FlightGlobals.fetch` property to not fallback to a `FindObjectOfType()` call when the `FlightGlobals._fetch` field is null, which is always the case during loading. In a stock + BDB test case, this alone was about 10% of the total loading time, 7+ seconds. The call doesn't seem necessary as `FlightGlobals._fetch` is set/unset from `FlightGlobals.Awake()` / `FlightGlobals.OnDestroy()`. I guess there are some very edge cases where a (just about to be destroyed) instance could be acquired by a call to `FindObjectOfType()`, but in any case I would qualify such behavior as a bug. On a side note, the same issue is present with `PhysicsGlobals`, but I haven't been able to detect any benefits in patching that one.
- New patch `PartParsingPerf`
  - Slightly faster part icon generation. Part icon GameObject generation is done by cloning the part prefab and basically removing everything on it. The operation represent roughly 35% of the part compilation time, a good two thirds of that being in instantiating the copy of prefab, and running all the associated code (part / modules KSPField scaffolding and Awake() code), only to immediately destroy everything. Unfortunately, this can't really be avoided due to the need to run `PartModule.OnIconCreate()` and in some case, some model-manipulation code in Awake().
  - Faster `Part` fields parsing, by creating a dictionary of IL-emitted parser delegates instead of the very generic reflection based stock approach.

Overall, these changes can provide a quite significant boost to loading time, mainly to part compilation and model loading. On a hot boot (config/model/texture loading not throughput limited by I/O), total time from exe launch to main menu for a stock + BDB install is now around 35 seconds on my 5800X3D.

Author: gotmachine

GameData/KSPCommunityFixes/Settings.cfg

@@ -459,6 +459,8 @@ KSP_COMMUNITY_FIXES
   // but this helps a bit in other cases as well.
   FloatingOriginPerf = true
 
+  PartParsingPerf = true
+
   // ##########################
   // Modding
   // ##########################

KSPCommunityFixes/BasePatch.cs

@@ -43,6 +43,17 @@ internal class TranspileInDebugAttribute : Attribute
     {
     }
 
+    /// <summary>
+    /// When applied to a class derived from <see cref="BasePatch"/>, the patch won't be automatically applied.<para/>
+    /// To apply the patch, call <see cref="BasePatch.Patch"/>. Note that if that call happens before ModuleManager
+    /// has patched the configs (ie, before part compilation), <see cref="BasePatch.IgnoreConfig"/> must be overriden
+    /// to return <see langword="true"/>, or the patch won't be applied.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Class, AllowMultiple = false)]
+    internal class ManualPatchAttribute : Attribute
+    {
+    }
+
     public abstract class BasePatch
     {
         public static readonly string pluginData = "PluginData";
@@ -64,7 +75,7 @@ public static void Patch(Type patchType)
 
             if (!patch.IgnoreConfig && !KSPCommunityFixes.enabledPatches.Contains(patchType.Name))
             {
-                Debug.Log($"[KSPCommunityFixes] Patch {patchType.Name} not applied (disabled in Settings.cfg)");
+                Debug.Log($"[KSPCommunityFixes] Patch {patchType.Name} not applied (not enabled in Settings.cfg)");
                 return;
             }
 

KSPCommunityFixes/KSPCommunityFixes.cs

@@ -14,7 +14,6 @@ public class KSPCommunityFixes : MonoBehaviour
 
         public static string LOC_KSPCF_Title = "KSP Community Fixes";
 
-
         public static Harmony Harmony { get; private set; }
 
         public static HashSet<string> enabledPatches = new HashSet<string>();
@@ -50,6 +49,14 @@ public static Version KspVersion
             }
         }
 
+        static KSPCommunityFixes()
+        {
+            Harmony = new Harmony("KSPCommunityFixes");
+#if DEBUG
+            Harmony.DEBUG = true;
+#endif
+        }
+
         public static T GetPatchInstance<T>() where T : BasePatch
         {
             if (!patchInstances.TryGetValue(typeof(T), out BasePatch instance))
@@ -72,11 +79,6 @@ void Start()
                 DontDestroyOnLoad(this);
             }
 
-            Harmony = new Harmony("KSPCommunityFixes");
-
-#if DEBUG
-            Harmony.DEBUG = true;
-#endif
             LocalizationUtils.GenerateLocTemplateIfRequested();
             LocalizationUtils.ParseLocalization();
 
@@ -113,10 +115,9 @@ public void MMPostLoadCallback()
             List<Type> patchesTypes = new List<Type>();
             foreach (Type type in Assembly.GetAssembly(basePatchType).GetTypes())
             {
-                if (!type.IsAbstract && type.IsSubclassOf(basePatchType))
+                if (!type.IsAbstract && type.IsSubclassOf(basePatchType) && type.GetCustomAttribute<ManualPatchAttribute>() == null)
                 {
                     patchesTypes.Add(type);
-
                 }
             }
 

KSPCommunityFixes/KSPCommunityFixes.csproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="..\packages\Krafs.Publicizer.2.2.1\build\Krafs.Publicizer.props" Condition="Exists('..\packages\Krafs.Publicizer.2.2.1\build\Krafs.Publicizer.props')" />
   <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
@@ -155,13 +155,16 @@
     <Compile Include="Library\LocalizationUtils.cs" />
     <Compile Include="Library\Numerics.cs" />
     <Compile Include="Library\ObjectPool.cs" />
+    <Compile Include="Library\MuParser.cs" />
+    <Compile Include="Library\ShaderHelpers.cs" />
     <Compile Include="Modding\KSPFieldEnumDesc.cs" />
     <Compile Include="Modding\ModUpgradePipeline.cs" />
     <Compile Include="Performance\ForceSyncSceneSwitch.cs" />
     <Compile Include="Performance\AsteroidAndCometDrillCache.cs" />
     <Compile Include="BugFixes\DoubleCurvePreserveTangents.cs" />
     <Compile Include="BugFixes\RestoreMaxPhysicsDT.cs" />
     <Compile Include="Performance\FloatingOriginPerf.cs" />
+    <Compile Include="Performance\GameDatabasePerf.cs" />
     <Compile Include="Performance\PartSystemsFastUpdate.cs" />
     <Compile Include="Performance\CollisionEnhancerFastUpdate.cs" />
     <Compile Include="Performance\CollisionManagerFastUpdate.cs" />
@@ -173,6 +176,7 @@
     <Compile Include="Performance\FasterPartFindTransform.cs" />
     <Compile Include="Performance\FastLoader.cs" />
     <Compile Include="Performance\FlightIntegratorPerf.cs" />
+    <Compile Include="Performance\PartParsingPerf.cs" />
     <Compile Include="Performance\IMGUIOptimization.cs" />
     <Compile Include="Performance\LocalizerPerf.cs" />
     <Compile Include="Performance\LowerMinPhysicsDTPerFrame.cs" />
@@ -254,6 +258,7 @@
   <ItemGroup>
     <None Include="packages.config" />
   </ItemGroup>
+  <ItemGroup />
   <!--Project-specfic configuration-->
   <PropertyGroup>
     <RepoRootPath>$(SolutionDir)</RepoRootPath>