[ue4] How to convert a cpp result struct/model to bp-friendly?

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dylan-1 asked Dec 10, '22

[ue4] How to convert a cpp result struct/model to bp-friendly?

I saw there are both cpp and bp models: However, the average dev uses both. Eg: as a backend dev, I get the data and prep some getters for the frontend to grab it via BP in a minimalist fashion.

Your cpp structs are quite complex, nested deep; and most notably: not friendly to manually recreate as a BP-friendly USTRUCT.

Since it was coded without considering BPs, is it safe to assume there's a tool to convert within the SDK?

Eg (pseudocode): Models::ParseUStructVariant<SomeCppModel>();

Where can I find this?

unreal

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dylan-1 commented · Dec 12, 2022 at 07:29 AM

Got a lead, maybe something like this?

const FString ClansJsonStr = MyClan.toJSONString(); // MyClan is the cpp model variant.
FGroupsGetGroupResponse* BPMyClan = NewObject();
FJsonObjectConverter::JsonObjectStringToUStruct(ClansJsonStr, BPMyClan);

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Answer 1 · 2022-12-13T06:53:27Z

dylan-1 answered Dec 13, '22

https://community.playfab.com/idea/67107/ue4-overload-bp-constructors-to-accept-the-cpp-mod.html

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Answer 2 · 2022-12-12T09:51:54Z

Rick Chen answered Dec 12, '22

There is no such function in Unreal SDK. You may feel free to create one by yourself.

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dylan-1 commented · Dec 13, 2022 at 06:48 AM

After attempting to create one, I realized it's very expensive and overly convoluted. The best answer seems to be to overload the USTRUCT constructor to allow a Cpp variant, then copy those vals over.

However, it's a pain since we'd have to edit your lib and feels like something that should already be there. Would you guys consider adding an update to accept a Cpp constructor in your models? I'm surely not the only developer that focuses on backend while another dev focuses on BPs.

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