Add to Spawn Actor Function Attributes Map

[MTeuberItemis]

Im currently trying to add an additional boolean to a walker, so I can set it from python scripts. It should work similar to e.g. "is_invincible". In python it looks like following: walker_bp.set_attribute('is_invincible', 'false')

I tried to figure out, how I can add such a boolean and managed to work my way to the "Spawn Actor" function in the WalkerFactory, where the following node seems to make it work:

The input, "Attributes", is unfortunately a mystery to me and I can't figure out, where I can add another ID to that Map.

When I print out the map, the following attributes are included:

LogBlueprintUserMessages: [WalkerFactory_C_0] role_name
LogBlueprintUserMessages: [WalkerFactory_C_0] gender
LogBlueprintUserMessages: [WalkerFactory_C_0] speed
LogBlueprintUserMessages: [WalkerFactory_C_0] is_invincible
LogBlueprintUserMessages: [WalkerFactory_C_0] generation
LogBlueprintUserMessages: [WalkerFactory_C_0] age

Can someone help me here?

This is carla 0.9.13

[Madecu]

Hi @MTeuberItemis,
Those attributes are declared in a C++ class.
First, you need to add your new variable to the Pedestrians structure.

Then, define it in ActorBlueprintsFunctionLibrary

[MTeuberItemis]

Thank you for that input, that already helps a lot.
But I still get some errors that I dont really understand.

There are two cases I tested with different outcomes: [everything in carla 0.9.13]

CASE 1:

I added following code:
PedestriansParameters.h: line 59 (bottom of the code)

...
UPROPERTY(EditAnywhere, BlueprintReadWrite)
bool on_wheelchair = false;
};

ActorBlueprintFunctionLibrary.cpp: line 1124:

Definition.Attributes.Emplace(FActorAttribute{
TEXT("on_wheelchair"),
EActorAttributeType::Bool,
GetWheelchair(Parameters.on_wheelchair)});

this resulted in a build error, when I tried to launch my locally built carla:
it stopped at module 5/8:

make: *** [CarlaUE4Editor] Fehler 6

CASE 2

inspired by: how "is_invincible" was added, i made no changes to original pedestrianparameters.h
and added following to
ActorBlueprintFunctionLibrary.cpp: line 1144:

FActorVariation OnWheelchair;
OnWheelchair.Id = TEXT("on_wheelchair");
OnWheelchair.Type = EActorAttributeType::Bool;
OnWheelchair.RecommendedValues = { TEXT("false") };
OnWheelchair.bRestrictToRecommended = false;

with this it was possible to build, but unfortunately when I tried to spawn walkers, it gave me following error:

Unknown error while trying to spawn actor

Interestingly, "on_wheelchair" also got added to the properties mentioned in my original question:

LogBlueprintUserMessages: [WalkerFactory_C_0] on_wheelchair
LogBlueprintUserMessages: [WalkerFactory_C_0] role_name
LogBlueprintUserMessages: [WalkerFactory_C_0] gender
LogBlueprintUserMessages: [WalkerFactory_C_0] speed
LogBlueprintUserMessages: [WalkerFactory_C_0] is_invincible
LogBlueprintUserMessages: [WalkerFactory_C_0] generation
LogBlueprintUserMessages: [WalkerFactory_C_0] age

[MTeuberItemis]

it was actually a problem in another part of the walkerFactory. the second approach works just fine. thank you