MeshShape serialization issues

[WholesomeIsland]

So I have the function below, it takes in lists of vertices and indices and converts them to the format expected by MeshShapeSettings, and I also have the serialization function shown as well, However when i do do the saving/serialization, nothing pops out.

Most of this I lifted pretty much straight from the saving shapes section of the docs.

Let me know if theres any other data I should provide.

JPH::Ref<JPH::Shape> mesh; 
    inline void Create(std::vector<glm::vec3> verts, std::vector<unsigned int> indices) {
        JPH::VertexList vertices;
        JPH::IndexedTriangleList indicesList;
        for (int i = 0; i < verts.size(); i++) {
            auto vert = verts[i];
            vertices.push_back(JPH::Float3(vert.x, vert.y, vert.z));
        }
        for (int i = 0; i < indices.size(); i += 3) {
            indicesList.push_back(JPH::IndexedTriangle(indices[i], indices[i + 1], indices[i + 2]));
        }
        {
        JPH::MeshShapeSettings meshSettings(vertices, indicesList);
        JPH::Shape::ShapeResult result = meshSettings.Create();
        mesh = result.Get();
        std::cout << result.HasError() << std::endl;
        if (result.HasError()) {
            std::cout << "MeshCollider creation failed" + result.GetError() << std::endl;
            return;
        }
        }
        std::cout << "MeshCollider created" << std::endl;
    }
    void save(Archive& archive) const {
        std::stringstream ShapeData;
        JPH::StreamOutWrapper stream(ShapeData);
        JPH::Shape::ShapeToIDMap shape_to_id;
        JPH::Shape::MaterialToIDMap material_to_id;
        mesh->SaveWithChildren(stream, shape_to_id, material_to_id);
        cereal::make_nvp("MeshShape", ShapeData.str()); // copys data inside ShapeData.str to a json file, nothing is outputted
        Save(archive); // function part of the PhysicsComponent base class, saves data like mass, type of object (RigidBody, Trigger, etc)
    }

[jrouwe]

I think the confusion is probably that ShapeData.str() is not an ASCII string. It's a binary stream of bytes that could start with a 0-byte. If you treat it as text and output it to JSON you would end up with an empty string. Check ShapeData.str().size(), I think it will be bigger than 0.

[WholesomeIsland]

no yeah, your right, the size of the string is 413, thanks for pointing me in the right direction.