Here’s some notes and details from the team with regards to the changes that come with KSP 1.8.0 Unity Upgrade Summary
KSP now runs on Unity 2019.2.2f1.
DX11 support. DX9 no longer supported.
.NET 3.5 is deprecated. So we switch it up to .NET4.x.
.NET 4 full API.
Now supporting C# 7.3 with Roslyn Compiler. Though we recommend you consider performance and Garbage generation within Unity when writing your code.
GPU instancing support.
PhysX 3.4.2 upgrade.
New Incremental Garbage Collector implemented.
Legacy particle system is gone.
Unity no longer supports DXT3 compressed DDS format
Project Plugin Upgrades
This is probably just for info, unlikely to be much direct correlation with mod authoring
TextMeshPro is now 1.2.2 in the main project, still not Unity native TMP
VPP is now SDK V6
Things to look out for when Updating C# Plugin DLLs
Change Target framework for your Mod application to .NET framework 4.x (any .NET > 4.x).
References: UnityEngine.DLL is now split across several DLLs. You should at least add UnityEngine.DLL and UnityEngine.CoreModule.DLL to your project references. There will be other references required depending on what the mod needs.
add UnityEngine.IMGUIModule.DLL - for any IMGUI mods.
add UnityEngine.InputLegacyModule.DLL - if you are references Input.
add UnityEngine.AnimationModule.DLL - if you reference Animations/AnimationState.
Texture2D.LoadImage - moved to ImageConversion.LoadImage - add UnityEngine.ImageConversionModule.DLL reference.
add UnityEngine.AudioModule.DLL for any audio mods.
If your automating builds using csc directly, nostdlib:, nosdkpath and direct refs to mscorlib, System.Core and System are recommended.
Notes about Part Tools
New part tools will be made available that contains latest part shaders for DX11 support.
Other than that, the same processes apply as always. Specific Changes to KSP Unity Changes
Coroutines returned from a MonoBehaviour while its GameObject is being disabled or destroyed are no longer started and Unity will report them as an error in the log.
DXT3 DDS formatted textures are not supported by Unity or KSP any more. You must convert to DXT5
You should not call the Log or log messages in class constructors.
GUISkin changes may require specifying ExpandWidth(true) GUIOption in some GUILayout calls - like GUILayout.Toggle to maintain visual appearance with 1.7.3 styles
New shader variants for the PQS terrain have been added. Low quality shaders are equivalent to the old shaders. Medium quality materials use the "Terrain/PQS/PQS Main - Optimised With Fast Blend" shader. High quality materials use the "Terrain/PQS/PQS Triplanar Zoom Rotation" shader.
The new PQS shaders require that the tangents be built for the PQS quads. Please turn on the setting for the PQS if you’re going to be using them.
The new shader for the KSC terrain is called "KSP/Scenery/Diffuse Ground KSC"
If your "Shader.Find" call does not find your old shader you can try to add "Legacy Shaders/" to the name. LIke "Legacy Shaders/Particles/Additive"
A number of shaders have been moved to legacy by Unity. However, a number of these have been made available by us in the distribution. Particularly particle shaders that are now marked as Legacy.
A number of tweaks were made to remove unnecessary, or massively repeated processing. Some of these you’ll find in the changelog as they are simply and should have no concern to modding. The below ones are unlikely to have an impact, but here's some extra detail that could be useful from what we have seen in code and mod testing
We’re caching the list of render meshes when parts are first created instead of “finding” them as the time as the meshes don’t change during flight in stock game. If you’re dynamically creating meshes which are then added to the vessel (or removing meshes), they might not be included in the mesh cache. Please call the following methods as appropriate when changing the meshes on a part:
Tooltips are now cached and re-used for performance reasons. If you have some information that is left over from a previously displayed tooltip, please make sure to overwrite it. Also, please clear any listeners that you might have on them when they’re finished being used as the methods will continue to be called in the future.
If you want to refresh the PAW for a part, please use MonoUtilities.RefreshPartContextWindow(part) as it has better performance than MonoUtilities.RefreshContextWindows(part)
Instead of using gameObject.GetComponentUpwards<Part>(), please use FlightGlobals.GetPartUpwardsCached(gameObject) instead for performance reasons. This gets the Part component that on this object or its parents, the first call stores that as a cached value and then returns the cache until the scene changes or the cache is cleared. Similar to the mesh renderer components above, if you are changing the hierarchy of the GOs and the parent Part has changed then there is a reset method you can call to reset the cache: `FlightGlobals.ResetObjectPartUpwardsCache().`
The value property of the VesselValues class now calculates the value only on the first “get” per frame (eg `vessel.AutopilotSkill`). The result is cached and the same result will be returned for the rest of the frame. If you require an uncached version then there is a valueUncached property. If you want to force the value to be updated so that the rest of the code uses it, please call the ResetValueCache() method so the next get call will recalc it.
The ProtoModuleSnapshot constructor does not create the confignode string at all times any more. As the configNode should only be used once the part is packed or the vessel is onrails or when making a backup of an existing protomodulesnapshot this was generating massive garbage and CPU hit for no purpose. If your code is accessing the snapshots when the partmodule is active then the suggestion is ensuring to only check that for unloaded vessels)
KerbalPortraitGallery.ActiveCrew is obsolete. Please use KerbalPortraitGallery.ActiveCrewItems.
Any mods that have KSPedia slides will likely have to recompiled the slides, please check your slides.