AirLib C++ API Mismatch for "simSpawnObject"

[drhill-larc]

Bug report

• AirSim Version/#commit: Main as of 06/23/2025; commit # 2831bd2
• UE/Unity version: Unreal 5.5.3
• autopilot version: N/A
• OS Version: Windows 11

What's the issue you encountered?

While using the C++ API within a client ros2 application, and I attempted to spawn a known Unreal asset object using "simSpawnObject." This produced a fatal exception repeatedly, and after much debugging it was determined that there was argument mismatch issue between the RpcLibClientBase::simSpawnObject function declaration and definition and the use of "simSpawnObject" by RcpLibServerBase (and WorldSimApiBase).

Under the function binding and redirection to WorldSimApiBase, RcpLibServerBase (Line 375 in RcpLinServerBase.cpp) expects a function argument list that includes an optional parameter "is_blueprint".

pimpl_->server.bind("simSpawnObject", [&](string& object_name, const string& load_component, const RpcLibAdaptorsBase::Pose& pose, const RpcLibAdaptorsBase::Vector3r& scale, bool physics_enabled, bool is_blueprint) -> string { return getWorldSimApi()->spawnObject(object_name, load_component, pose.to(), scale.to(), physics_enabled, is_blueprint); });

However, the calling object, RcpLibClientBase, does not expect nor provide this parameter when being executed and subsequently issuing the pimpl client call (starting at line 516 of RcpLinClientBase.cpp).

std::string RpcLibClientBase::simSpawnObject(const std::string& object_name, const std::string& load_component, const Pose& pose, const Vector3r& scale, bool physics_enabled) { return pimpl_->client.call("simSpawnObject", object_name, load_component, RpcLibAdaptorsBase::Pose(pose), RpcLibAdaptorsBase::Vector3r(scale), physics_enabled).as<std::string>(); }

By adding the optional parameter "is_blueprint" to RpcLibClientBase::simSpawnObject function and correctly passing "is_blueprint" within the function body's pimpl call, the issue was resolved.

Affected Files:
"/AirLib/include/api/RpcLibClientBase.hpp"
"/AirLib/src/api/RpcLibClientBase.cpp"

Settings

N/A

How can the issue be reproduced?

-Create a c++ node application that does the following:
-Create a client connection to an Active Unreal Airsim environment.
-Attempt to spawn an object (non airsim vehicle actor) such as any of the starting content meshes; e.g. "Shape_Cone" or "Shape_Sphere"

You can test this spawning with a python client first, as this function doesn't fail with the python client interface.

Include full error message in text form

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