You mention that, because templates require definitions of the methods in the .h files anyway, the FORCEINLINE keyword should be used. I don’t really agree with that as a rule of thumb. Inlining functions increases the size of the code. Sometimes, people may not care about the size of the code and only the number of CPU cycles it takes to run, and then I agree that FORCEINLINE would often result in a performance increase… but even that is not always true. The increased code size can have a negative impact on your performance, even taking into account that the function call overhead is avoided (see Sections 3.4 and 6.2.2 of http://www.akkadia.org/drepper/cpumemory.pdf).
I would strongly recommend not to use FORCEINLINE at all, unless extensive profiling indicates that it does result in better performance in a highly performance-critical area of the game’s code. In general, it is fairly safe to rely on the compiler to make the right decisions with respect to whether or not code should be inlined (it can still do so even if you don’t use the FORCEINLINE or inline keywords).
I’ve modified the wiki to mention that you should probably just let the compiler figure it out if your function body is large!
I am presuming that readers of my wiki will actually look up “C++ inline function” and read about all these details, including your concerns about code bloat.
I can’t explain everything in my wiki pages
In case you’re wondering, I am assuming that readers of my wiki understand that C++ is one of the most well-documented languages on the planet, and they can find out more information about any topic by searching for themselves
But thanks again for your input, I’ve modified my phrasing on the wiki to make it more clear that user discretion is required when using FORCEINLINE!
I am giving you easy-to-use pre-processor commands to get a UE4 String that tells you the Class Name, Function Name, and Line Number of the calling code!
Logs, Printing the Class Name, Function Name, and Line Number of your Calling Code!
**Pics**
After you get my .h file below, the code for the above picture is this!
```
//~~~ Tick ~~~
void AEVCoreDefense::Tick(float DeltaTime)
{
Super::Tick(DeltaTime);
//~~~~~~~~~~~~~
VSCREENMSG("Got Here!"); //Class and line number get printed for you! ♥ Rama
}
```
Code
Here is the entire file you can #include in your code base!
I made this a file called JoyCurrentClassFuncLine.h
So you would then do this somewhere at the top of one of your core classes:
// Joy Class Func Line
**#include "JoyCurrentClassFuncLine.h"**
**/*
Joy String
Current Class, File, and Line Number!
by Rama
PreProcessor commands to get
a. Class name
b. Function Name
c. Line number
d. Function Signature (including parameters)
Gives you a UE4 FString anywhere in your code that these macros are used!
Ex:
You can use JOYSTR_CUR_CLASS anywhere to get a UE4 FString back telling you
what the current class is where you called this macro!
Ex:
This macro prints the class and line along with the message of your choosing!
VSCREENMSG("Have fun today!");
<3 Rama
*/**
#pragma once
**//Current Class Name + Function Name where this is called!**
#define JOYSTR_CUR_CLASS_FUNC (FString(__FUNCTION__))
**//Current Class where this is called!**
#define JOYSTR_CUR_CLASS (FString(__FUNCTION__).Left(FString(__FUNCTION__).Find(TEXT(":"))) )
**//Current Function Name where this is called!**
#define JOYSTR_CUR_FUNC (FString(__FUNCTION__).Right(FString(__FUNCTION__).Len() - FString(__FUNCTION__).Find(TEXT("::")) - 2 ))
**//Current Line Number in the code where this is called!**
#define JOYSTR_CUR_LINE (FString::FromInt(__LINE__))
**//Current Class and Line Number where this is called!**
#define JOYSTR_CUR_CLASS_LINE (JOYSTR_CUR_CLASS + "(" + JOYSTR_CUR_LINE + ")")
**//Current Function Signature where this is called!**
#define JOYSTR_CUR_FUNCSIG (FString(__FUNCSIG__))
**//Victory Screen Message
// Gives you the Class name and exact line number where you print a message to yourself!**
#define VSCREENMSG(Param1) (GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, *(JOYSTR_CUR_CLASS_LINE + ": " + Param1)) )
I added some additional pre-processor commands to my wiki above!
UE_LOG and additional Screen Msg commands, that all tell you where you are in your code base automatically, including the line number!
// Joy Class Func Line
**#include "JoyCurrentClassFuncLine.h"**
**/*
Joy String
Current Class, File, and Line Number!
by Rama
PreProcessor commands to get
a. Class name
b. Function Name
c. Line number
d. Function Signature (including parameters)
Gives you a UE4 FString anywhere in your code that these macros are used!
Ex:
You can use JOYSTR_CUR_CLASS anywhere to get a UE4 FString back telling you
what the current class is where you called this macro!
Ex:
This macro prints the class and line along with the message of your choosing!
VSCREENMSG("Have fun today!");
<3 Rama
*/**
#pragma once
**//Current Class Name + Function Name where this is called!**
#define JOYSTR_CUR_CLASS_FUNC (FString(__FUNCTION__))
**//Current Class where this is called!**
#define JOYSTR_CUR_CLASS (FString(__FUNCTION__).Left(FString(__FUNCTION__).Find(TEXT(":"))) )
**//Current Function Name where this is called!**
#define JOYSTR_CUR_FUNC (FString(__FUNCTION__).Right(FString(__FUNCTION__).Len() - FString(__FUNCTION__).Find(TEXT("::")) - 2 ))
**//Current Line Number in the code where this is called!**
#define JOYSTR_CUR_LINE (FString::FromInt(__LINE__))
**//Current Class and Line Number where this is called!**
#define JOYSTR_CUR_CLASS_LINE (JOYSTR_CUR_CLASS + "(" + JOYSTR_CUR_LINE + ")")
**//Current Function Signature where this is called!**
#define JOYSTR_CUR_FUNCSIG (FString(__FUNCSIG__))
**//Victory Screen Message
// Gives you the Class name and exact line number where you print a message to yourself!**
#define VSCREENMSG(Param1) (GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, *(JOYSTR_CUR_CLASS_LINE + ": " + Param1)) )
#define VSCREENMSG2(Param1,Param2) (GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, *(JOYSTR_CUR_CLASS_LINE + ": " + Param1 + " " + Param2)) )
#define VSCREENMSGF(Param1,Param2) (GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, *(JOYSTR_CUR_CLASS_LINE + ": " + Param1 + " " + FString::SanitizeFloat(Param2))) )
//UE_LOG Messages!
#define V_LOG(Param1) UE_LOG(Joy,Warning,TEXT("%s: %s"), *JOYSTR_CUR_CLASS_LINE, *FString(Param1))
#define V_LOG2(Param1,Param2) UE_LOG(Joy,Warning,TEXT("%s: %s %s"), *JOYSTR_CUR_CLASS_LINE, *FString(Param1),*FString(Param2))
#define V_LOGF(Param1,Param2) UE_LOG(Joy,Warning,TEXT("%s: %s %f"), *JOYSTR_CUR_CLASS_LINE, *FString(Param1),Param2)
AI Navigation in C++, Customize Path Follwing Every Tick!**
Shows you how to extend UE4’s wonderful AI Path Folllowing foundation by adding your own C++ that will run every tick that the path following is occurring!
This lets you add to UE4 Path Following without having to rewrite the whole thing from scratch, you can inject your own code per-tick into the standard UE4 path following code!
I used what I share in the wiki below to make c++ dynamic jump pathing, as shown in the AI videos in my signature.
I’ve added a section showing you how to get the Nav Polys, the actual individual units of the nav mesh system, so you can do completely custom calculations like I do in this video below!
Thanks for your awesome wiki contribution, wohooo! Really useful!
**Use C++ Operator New Instead of Malloc**
Using Malloc does not initialize the Vtable! So virtual functions will crash!
I recommend that you use C++ operator **new** to get around this, which both
a. calls the constructor of the data type
b. properly initializes the VTable (virtual function table)
I updated my wiki with this information
**UE4 Dynamic Memory Management**
https://wiki.unrealengine.com/Garbage_Collection_%26_Dynamic_Memory_Allocation#Every_New_Must_Have_a_Delete
♥
Rama
I recently wrote a wiki on how to add to the UE4 C++ AI path following system, to add in custom pathing coding!
UE4 Wiki Link: Writing Custom C++ AI Code
Well I now have my best demo yet of the effectiveness of this coding structure!
I prove to you in the video that I am using just multi-threaded C++ to dynamically calculate AI Jump paths for my AI units to follow the player through many complex jumping sequences!
I am using just C++ coding, no helpers in the editor!
2.** In this thread I share my own UE4 C++ code with you** for how to get all the nav polys, the actual portions of the nav mesh so that you can do your own fancy custom UE4 C++ AI pathing code!
In this thread I also show you how I know when the UE4 pathing system can’t find a way to the player without doing jumps!
**Video: Rama's Multi-Threaded C++ AI Jump Pathing**
https://youtube.com/watch?v=sMMSQdnyt6o
Once again, I am doing all the jumping calculations **dynamically via C++** using the nav areas and my custom path following component!
Mult-Threaded
The code I use in this video is multi-threaded using the UE4 C++ Task Graph system:
UE4 Wiki Link: UE4 Multi-threading
**C++ Code For You**
I inject my custom AI jump pathing code in this way:
```
/*
Custom UE4 C++ AI Path Follow Component
By Rama
*/
#pragma once
//Super
#include "Navigation/PathFollowingComponent.h"
UCLASS()
class UJoyPathFollowComp : public UPathFollowingComponent
{
GENERATED_BODY()
public:
UJoyPathFollowComp(const FObjectInitializer& ObjectInitializer);
/** follow current path segment */
virtual void FollowPathSegment(float DeltaTime) override;
};
```
```
void UJoyPathFollowComp::FollowPathSegment(float DeltaTime)
{
//Pointer Safety Checks
if (MovementComp == NULL || !Path.IsValid())
{
return;
}
//~~~~~~~~~~~~~~~~~~~~~~~~~
//~~~~~~~~~~~~~~~~~~~~~~~~~~~
//Use Jump/Fall Pathing?
//~~~~~~~~~~~~~~~~~~~~~~~~~~~
if(Path->IsPartial()) //AI could not reach player, try using jump pathing!
{
//I send out instructions to my custom character class here
JoyChar->ReceiveJumpFallPathingRequest();
return;
//~~~
}
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//Proceed normally (no jump pathing)
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Super::FollowPathSegment(DeltaTime);
}
```
Explanation
FollowPathSegment is the main UE4 Path Follow tick function, and so when you want to add completely custom coding you can use this function as your starting point to adjust normal UE4 pathing behavior!
Path is Partial
The way I tell whether I need to try using custom jump pathing code is whether or not the UE4 Pathing system has detected a partial path!
Then my AI jump code runs and teaches the AI to get to the player using C++ calculated Jumps!
if(Path->IsPartial()) //AI could not reach player, try using jump pathing!
**How to Get all the UE4 Nav Polys**
In the video above you will see I get all the UE4 Nav Polys in order to do all my C++ AI Jump calculations!
Here's the function I wrote to do this, just for you!
```
**// Rama UE4 C++ AI Code for you!
// add this to your custom path follow component!**
**//Nav Data Main**
FORCEINLINE const ANavigationData* **GetMainNavData**(FNavigationSystem::ECreateIfEmpty CreateNewIfNoneFound)
{
UNavigationSystem* NavSys = GetWorld()->GetNavigationSystem();
if(!NavSys) return NULL;
return NavSys->GetMainNavData(CreateNewIfNoneFound);
}
**//Choose Which Nav Data To Use**
FORCEINLINE const ANavigationData* **JoyGetNavData()** const
{
if(!MovementComp)
{
return GetMainNavData();
}
const FNavAgentProperties& AgentProperties = MovementComp->GetNavAgentPropertiesRef() ;
const ANavigationData* NavData = GetNavDataForProps(AgentProperties) ;
if (NavData == NULL)
{
VSCREENMSG("ERROR USING MAIN NAV DATA");
NavData = GetMainNavData();
}
return NavData;
}
//VERY IMPORTANT FOR CRASH PROTECTION !!!!!
FORCEINLINE bool **TileIsValid**(const ARecastNavMesh* NavMesh,int32 TileIndex) const
{
if(!NavMesh) return false;
//~~~~~~~~~~~~~~
const FBox TileBounds = NavMesh->GetNavMeshTileBounds(TileIndex);
return TileBounds.IsValid != 0;
}
bool **NavPoly_GetAllPolys**(TArray<NavNodeRef>& Polys);
```
```
**//Rama's UE4 Nav code to get all the nav polys!**
bool UJoyPathFollowComp::****NavPoly_GetAllPolys****(TArray<NavNodeRef>& Polys)
{
if(!MovementComp) return false;
//~~~~~~~~~~~~~~~~~~
//Get Nav Data
const ANavigationData* NavData = JoyGetNavData();
const ARecastNavMesh* NavMesh = Cast<ARecastNavMesh>(NavData);
if(!NavMesh)
{
return false;
}
TArray<FNavPoly> EachPolys;
for(int32 v = 0; v < NavMesh->GetNavMeshTilesCount(); v++)
{
//CHECK IS VALID FIRST OR WILL CRASH!!!
// 256 entries but only few are valid!
// using continue in case the valid polys are not stored sequentially!
if(****!TileIsValid****(NavMesh,v))
{
continue;
}
NavMesh->GetPolysInTile(v,EachPolys);
}
//Add them all!
for(int32 v = 0; v < EachPolys.Num(); v++)
{
Polys.Add(EachPolys[v].Ref);
}
}
```
Enjoy!
Have fun writing custom UE4 AI C++ code and getting all the nav polys so you can truly do whatever you want with UE4’s awesome navigation system!
Now that is creative 
