Blueprint real number support.
This change deprecates the use the of "float" and "double" types in Blueprints in favor of a new "real". By default, "real" is back by a double precision floating point number. However, it can be single precision if the number is a native float property or function parameter. This distinction won't be visible to the Blueprint user: in both instances, they'll be represented by "real" pin types. During deserialization, we'll automatically convert Blueprint pin types to use real/doubles, unless they're used to represent native code (including delegate signatures).
One consequence of this change is that we need to perform implicit casts between single and double precision real numbers. During Blueprint compilation, the compiler will detect points in the graph for when either a widening or narrowing conversion needs to occur. Subsequently, the script bytecode will contain a new cast instruction that performs the conversion. This also works on container types, but each entry in the container will have to be converted. This can introduce unwanted overhead for large containers that are frequently passed between Blueprint and native code.
The scope of this change affects Blueprints used by Gameplay, Animation, Control Rig, and UMG.
#rb marc.audy (serialization changes)
#jira UE-116484
#preflight 61f8bdd5a2514ba12ff7bdfc
#ROBOMERGE-AUTHOR: dave.jones2
#ROBOMERGE-SOURCE: CL 18809077 in //UE5/Release-5.0/... via CL 18809455 via CL 18822548
#ROBOMERGE-BOT: UE5 (Release-Engine-Test -> Main) (v908-18788545)
[CL 18823569 by dave jones2 in ue5-main branch]
#rnx
#rb none
#ROBOMERGE-SOURCE: CL 10869241 via CL 10869527 via CL 10869904
#ROBOMERGE-BOT: (v613-10869866)
[CL 10870586 by ryan durand in Main branch]
#lockdown Nick.Penwarden
#rb none
==========================
MAJOR FEATURES + CHANGES
==========================
Change 3209340 on 2016/11/23 by Ben.Marsh
Convert UE4 codebase to an "include what you use" model - where every header just includes the dependencies it needs, rather than every source file including large monolithic headers like Engine.h and UnrealEd.h.
Measured full rebuild times around 2x faster using XGE on Windows, and improvements of 25% or more for incremental builds and full rebuilds on most other platforms.
* Every header now includes everything it needs to compile.
* There's a CoreMinimal.h header that gets you a set of ubiquitous types from Core (eg. FString, FName, TArray, FVector, etc...). Most headers now include this first.
* There's a CoreTypes.h header that sets up primitive UE4 types and build macros (int32, PLATFORM_WIN64, etc...). All headers in Core include this first, as does CoreMinimal.h.
* Every .cpp file includes its matching .h file first.
* This helps validate that each header is including everything it needs to compile.
* No engine code includes a monolithic header such as Engine.h or UnrealEd.h any more.
* You will get a warning if you try to include one of these from the engine. They still exist for compatibility with game projects and do not produce warnings when included there.
* There have only been minor changes to our internal games down to accommodate these changes. The intent is for this to be as seamless as possible.
* No engine code explicitly includes a precompiled header any more.
* We still use PCHs, but they're force-included on the compiler command line by UnrealBuildTool instead. This lets us tune what they contain without breaking any existing include dependencies.
* PCHs are generated by a tool to get a statistical amount of coverage for the source files using it, and I've seeded the new shared PCHs to contain any header included by > 15% of source files.
Tool used to generate this transform is at Engine\Source\Programs\IncludeTool.
[CL 3209342 by Ben Marsh in Main branch]
Function result node generates KCST_GotoReturn statement.
"The execution path doesn't end with a return node." Is now a note.
#codereview Mike.Beach, Michael.Noland
[CL 2508745 by Maciej Mroz in Main branch]
