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[madbranch]

Hi,
My friends I have been working on a game engine project (RedBox engine) and recently we were looking at the possibilities for serialization/deserialization for many purposes in the engine. We have looked at XML and JSON libraries in C++. For XML, the choice is pretty simple, we went with TinyXML which is great for our needs, but we've had some problems with finding a good JSON library that felt clean enough, was object oriented and didn't require Boost.

So like any good developer, I decided to roll with our own JSON library. I've started it last week and currently have a prototype that is starting to be stable and I'd like to know what people think of it...

If anyone's interested in reading and writing JSON in C++, you can check out my library I named JsonBox (to fit with our engine's name, RedBox, lol). It uses a part of code from our engine to encode unicode characters to UTF8, so i copied it in the repository to simplify its use.

https://bitbucket.org/madbranch/jsonbox

Right now it reads and writes with a recursive algorithm, which might not be the brightest idea, but I'm looking at the possibilities to change that.

If you still have questions after reading this post and the README, I'd be glad to answer them.

What do people think of this yet-another-json-reading-library ?

[mcc]

Omg, looking forward to checking this out. I've been looking for something like this...

[Vino]

I looked into a bunch of JSON libraries for my game when I wanted to start serializing game scripts and data to and from the hard drive. In the end I decided that even JSON was too heavyweight for me and I went with a custom scripting engine that only took me a few hours to write. The syntax is stupid simple so my artist can work easily with it (not that he's stupid) and the code is ridiculously small. I try not to reinvent the wheel but I think I made a good choice there.

Sorry I guess none of this has to do with your library. Looks neat though 

[Hima]

Have you tried this?   https://github.com/MJPA/SimpleJSON
It's C++, lightweight and requires no 3rd party libraries such as boost. Seems to fit your requirement quite well!

Anyway, I think it's always good to have an option. I might write a wrapper for Monkey and C++ JSON library so I'll see if it works well with your library.

[Vino]

My problem wasn't just with the JSON library but also with JSON itself. This is JSON:

Code:

{"menu": {
  "id": "file",
  "value": "File",
  "popup": {
    "menuitem": [
      {"value": "New", "onclick": "CreateNewDoc()"},
      {"value": "Open", "onclick": "OpenDoc()"},
      {"value": "Close", "onclick": "CloseDoc()"}
    ]
  }
}}

This is my markup:

Code:

Entity
{
Class: BugTurret
Team: Hackers
Position: -57, 11
Angle: 0

Output: OnBecomeFullyVisible
{
Target: instructor
Input: DisplayLesson
Args: mission-1-turret-spotted
Kill: yes
}
}

Since JSON is really just a Javascript array it's a bit conceptually more difficult and easier to fuck up if you're just an artist trying to install a new sprite or a writer trying to add a new page of dialogue. Miss a comma and JSON isn't very forgiving.

[Hima]

I was suggested that the safest way for artists/writers/non-programmers to deal with this is to do it in excel, and then try to find someway to convert the excel file to JSON.

If you use Google Docs, there is a widget that will allow you to do just that. It's hard to miss a comma in excel

[BorisTheBrave]

My problem wasn't just with the JSON library but also with JSON itself.

Sounds like you want YAML.

[madbranch]

YAML does indeed look interesting to use.

But as it says in http://yaml.org/spec/1.2/spec.html#id2759572 in the specification, YAML really aims at human readability at the cost of ease of parsing, writing and portability. We went with JSON because one of our engine's main objective is extreme portability.
Like right now, it works on Windows, Linux, Mac OS, iOS and just recently Haiku (took like 2 hours to setup). We're currently working to make the engine work on Android.

YAML would have probably been fine too and we might actually look into implementing it later.

Excel would probably be cool, but isn't it a bit of a heavy format? Depending on your project, needing a google widget might not always be awesome lol

[Vino]

Yeah I considered YAML too but it was still a bit too technical for me.

And I really like that spreadsheet idea.

[Hima]

Right, spreadsheet! People around here call it excel file so the word escaped me 
Anyway, by excel file I mean any spreadsheet. And you don't need to include the original file in your game, you include the translated JSON from that spreadsheet. The google widgetgadget do the conversion from spreadsheet -> JSON for you then you can copy'n paste that JSON into a text file and use that in your game

Here's a website that tell you how to do it
http://blog.pamelafox.org/2009/05/how-to-convert-google-spreadsheet-into.html

[Tycho Brahe]

Nice! I looked at json for my last project, but couldn't really be bothered to take the time to work it out and find a nice library. You should contact the json people and get listed on their frontpage, it would really increase your exposure, and thus testing base.

[madbranch]

I like your idea 14113, I hadn't thought of it lol. So I prepared my repository a bit and I contacted Douglas Crockford. Now my library is available through http://www.json.org in the list of C++ JSON library at the bottom.   :D

[Tycho Brahe]

I like your idea 14113, I hadn't thought of it lol. So I prepared my repository a bit and I contacted Douglas Crockford. Now my library is available through http://www.json.org in the list of C++ JSON library at the bottom.   :D

Awesome!