Adding camera matricies to JSON

[el3ment]

I'm trying to add avg_world, avg_world_view, and avg_world_view_proj to the JSON output. I've created a new function:

std::string toJSON(float4x4 & f) {
    std::stringstream s;
    s << "[ [" << f.d[0][0] << ", " << f.d[0][1] << ", " << f.d[0][2] << ", " << f.d[0][3] << "], ["
        << f.d[1][0] << ", " << f.d[1][1] << ", " << f.d[1][2] << ", " << f.d[1][3] << "], ["
        << f.d[2][0] << ", " << f.d[2][1] << ", " << f.d[2][2] << ", " << f.d[2][3] << "], ["
        << f.d[3][0] << ", " << f.d[3][1] << ", " << f.d[3][2] << ", " << f.d[3][3] << "] ]";
    return s.str();
}

And added members to the GameInfo:

struct GameInfo {
    int time_since_player_hit_vehicle;
    int time_since_player_hit_ped;
    int time_since_player_drove_on_pavement;
    int time_since_player_drove_against_traffic;
    int dead;
    Vec3f position, forward_vector;
    float heading;
    int on_foot, in_vehicle, on_bike, money;
    float4x4 avg_world;
    float4x4 avg_world_view;
    float4x4 avg_world_view_projection;
};

And added the members to the TOJSON macro:

TOJSON(GameInfo, time_since_player_hit_vehicle, time_since_player_hit_ped, time_since_player_drove_on_pavement, time_since_player_drove_against_traffic, dead, position, forward_vector, heading, on_foot, in_vehicle, on_bike, money, avg_world, avg_world_view, avg_world_view_projection)

But, the output returns just a "1": {"time_since_player_hit_vehicle":-1,"time_since_player_hit_ped":-1,"time_since_player_drove_on_pavement":-1,"time_since_player_drove_against_traffic":-1,"dead":0,"position":[-14.380300,-1438.514282,31.101547],"forward_vector":[0.222740,-0.974878,0.000000],"heading":192.870010,"on_foot":1,"in_vehicle":0,"on_bike":0,"money":11,"avg_world":1,"avg_world_view":1,"avg_world_view_projection":1,"timestamp": 1534989424.864456}

Any ideas?