I want Feedback from Epic about Mono for Unreal Engine

Mate I dont wanna seem as troll but people who wants to use C# over C++, please just leave and use Unity.
Unreal is designed for top class AAA games mainly, indie developers is not on top priority take it or not.

It is supported, in a “if it is broken, bug it and we’ll try and fix it”, but features are backlogged right now. It could be picked up by the community and taken the last mile, however, and Lua’s runtime source license is very flexible (as is LuaJit, a better runtime for games).

Please let’s not start this kind of thing. We don’t want to foster that kind of exclusionary behavior here.

It’s a similar system adopted in SnowDrop engine to allow 3D artists to add gameplay to their 3D models without knowing a programming language.

lol, you are persistant, I’ll give ya that

but to start a debate over C#, because that’s exactly what this is, then say you don’t want a debate?

I don’t care if I ever see C# again, it wasn’t bad, but it sure isn’t good either, it’s nothing but a subset of C++ in my opinion and will be nothing else, heck I think plain C is better.
I don’t want to take another hit to performance, I can deal with the scripting hit from BPs but another, no thank you.
I don’t ever want to see C# in Unreal Engine unless it’s a plugin to access Windows Phone, and that’s it.

BP is a scripting language, have you tried it? you can make your own BPs, anyone can. you should try it because in the time it takes you to ‘debate’ this subject you could already be using C++.
you don’t have to use C++ at all if you don’t want to, Unreal has exposed & are exposing more & more to BPs every day.

But can you tell me that ‘those Other Guys’ don’t use C or C++ for their actual engine and expose all of this to you as a user like Unreal does, check this out puppy:
"The Unity runtime is written in C/C++. This runtime is used in any build you create using the editor - for webplayers and plugins it is installed separate from your build, whereas it is included in it for stand-alones and other platforms such as iPhone and Wii.

The editor is built on the Unity runtime and additionally includes editor-specific C/C++ binaries.
Wrapped around the Unity core is a layer which allows for .net access to core functionality. This layer is used for user scripting and for most of the editor UI."

Unreal Engine 4 has exposed it’s engine to you if you need it, and a strong API that allows access to it as well. On top it has BPs which is really more powerful than they can even imagine.
if I, lol woops WE keep pushing them in the right direction. (yes, a lil’ world domination coming through there)

K, enough of this, simple solution is you need to watch for a Twitch stream that has someone involved with the engine & ask your questions, like everyone else does.
(if they can’t answer then they can probably find someone who can, and give you a reasonable response)
So if you have concerns or questions that bother you this much, take the time to ask on twitch, if you can’t make the Twitch ask in the twitch announcement post & watch the Twitch later when it’s posted on YouTube.

Again… completely against the idea, I hated being forced to try to use C# & .Net when I had to and I don’t want to ever see it again.
(you can’t even do the simplest things in C# sometimes, C++ has stayed this long for a reason)

Xamarin’s C# integration is promising and follows a technically well thought-out design, however this is a fairly complicated topic.

The challenge with this and other programming language integrations into Unreal Engine 4 is that, unless they were to be genuinely and thoroughly adopted by Epic, they would not quite be first-class citizens in the way that C++ and Blueprints are. Specifically, we put substantial work into documentation, samples, pre-release testing, compatibility, porting, and support on C++ and Blueprints that we can’t feasibly replicate for a third-party plug-in. For example, unless the documentation on UE4 programming were updated to include side-by-side examples of C++ and C#, the programming experience with C# in UE4 could feel disjointed, and this downside may outweigh the upside of one’s familiarity with C# and its easier header-free programming model.

Programming language integrations are very different in nature than middleware integrations such as SpeedTree and Substance in this regard. Though the later are feature-rich, they are fairly self-contained in their interactions with UE4. A programming language integration can interact with just about any part of the engine and therefore has unlimited scope.

For these reasons, we updated the UE4 EULA to require redistributed programming language integrations to be free and open source, so that if one gained a critical mass in popularity, Epic could adopt it and ensure its future viability in the areas described above. I’m hopeful Xamarin’s C# integration goes this route in transitioning from closed beta to full release but I can’t speak for them.

There is another key point to consider: C# in UE4 more closely resembles C++ in UE4 than it resembles C# in Unity. Unity users coming from a background working with the componentized C# behavior model with Unity’s MonoBehaviour framework will find that UE4 doesn’t follow that model and therefore the emergence of UE4 C# support isn’t quite the hoped-for panacea.

Finally, when an engine is written in C++ and gameplay is scripted in another language, the interoperability barrier between languages eventually grows overwhelming. This is why we ultimately abandoned the UE1-3 era’s UnrealScript language and moved to a pure C++ programming model. This gives UE4 the ironic property of making it harder to learn the engine and start writing a game, yet ultimately easier to grow, finish, and ship.

Therefore, my recommendation for developers who want to use UE4 but prefer C# over C++ is to bite the bullet and give C++ a thorough chance. All of us at Epic clearly see the many ways that programming in C# is more enjoyable than C++, from header-free source code to generics to rediced boilerplate code. However, C++ is a language that scales upward without limit, and the experience of whole-program debugging (engine and game together) is incredibly illuminating, as are the power and visibility that come from having the full C++ source and ability to call into any part of it.


Thanks for the clarification Tim.

Which kind of halted my endeavors to make UE4 compatible with the Embacadero RAD studio so I could enhance the engine as a Delphi programmer, so my 15+ years of coding expierience wouldnt be down the drain…(RAD Studio allows cross coding).
Side question to that: Would it be Ok to use the Rad Studio C++ Builder together with UE4? (I really really dont like Visual Studio…)

Im thinking however to make a little framework for custom dlls. If they use the FreePascal compiler (which can also compile ObjectPascal code), that would be ok since its free, right?


Thanks Tim, for that clarification.

Few comments though…

What about Blueprints ? You are not very constant in you argumentation since one can develop its own game-play via another programming paradigm than C++…

I shall also remind that all “Mono for Unreal” does is exposing to a C# environment the blueprint-exposed functions that are already defined in the C++ environment, and therefore maintaining the C# API would rather be trivial.

tl;dr -> Blueprints-exposed code in the C++ will automatically be made available in C# via the tool.

Do you think that if Mono was completely open-source and free to use for any body then Epic would have done it’s move towards Xamarin ?

We actually love scripting languages, and we want developers to be able to use the right tool for the job. We designed the scripting layer in Unreal Engine to be totally extensible through a pluggable API that uses the same surface area as our own Blueprint language. So you guys are free to use whichever language you want or create your own!

As Tim said, we do require that language extensions to the engine to be totally free and open source. We believe this is in best interest of the Unreal Engine community. Just as an example, if a huge number of developers suddenly adopted using Google’s GoLang for their projects, we would want to be able to make Go a built-in feature and support it at the same quality level as Blueprints (sample games, documentation, templates, video tutorials) and ensure developers could release projects on all platforms without restriction.

We’re really still focused on making the C++ experience awesome for developers. We have dozens of improvements coming, including faster compile times, fast code outdatedness checking, simplified Unreal Object syntax, and better API documentation. Of course many of these improvements will benefit scripting languages as well, and with every release we expose more engine features to scripting APIs.

We do certainly keep an eye on .NET and other languages. We talk to Microsoft frequently and we’re pleased they’re opening up the core .NET code. For the foreseeable future we have our hands full with improvements to Blueprints and C++. We have a great trajectory with these languages and some extremely cool ideas yet to implement that we’re very excited about.

Please keep the feedback coming, we are always listening and trying to do the right thing for the engine and developers.


I think you need to use Mono and give it a chance if that’s what you want. put your efforts there or are they not answering your concerns like UE has?

Epic has kept this Feedback Forum open and even though I don’t agree with what you suggest (at this time), I agree that you should be able to voice your opinion, as should they be able to voice theirs. And they are a lot nicer than I would be.
(maybe one day I’ll look back at C# & even Mono but not today because I’ve seen what they both can do)

Whether I agree with Epic, whether I like what they are doing all the time, whether I’m able to make something out of Unreal Engine or not, whether I stay or go, I still believe in Epic & Unreal Engine and what they are trying to do here. They listen and try to go forward with the community & their users in mind. And I will always uphold their right to do so, because it’s something I believe in, as do many if not all of this community.

If it seems I took offense, maybe I did, and I’ll take this moment to apologize for it if I offended you or anyone. But it’s because they do answer these concerns when they can or when they have an answer that is correct for the situation or the timing is right. This you should respect, as I suggested above you should take the time, if you can, to join the Twitch streams, voice your concerns etc. and there is also an Off-Topic forum thread that I’m sure you can continue your topic with. (if you can’t make the Twitch you can ask the question in the Twitch Announcement topic)(look for someone that has something to do with your topic in the stream is best though)(never hurts to ask)

So again, if I offended anyone in any way, my apologies. And Epic/UE4 you make me proud to be a part of this community! I still don’t want C# tho’, not today anyway! :stuck_out_tongue:

I’ve tried Mono for Unreal already, but the tool is simply not mature enough yet because they lack the man-power to develop it, therefore I think it is up to Epic to take responsibility because the potential is simply enormous, for both Epic and Xamarin – just think one minute how popular it would be if every Unity user suddenly started to use Unreal Engine instead.

Epic wants to allow level-designer and artists to script the game play via Blueprint, and that is the proof they want to open game development to a larger group of potential users, in that case it would also make sense to open it to lamba-developers, don’t you think ?

You don’t want C#, fine, some people do not want Blueprints either and yet there no one is making a drama about it.

The C++ in Unreal is not C++, I mean it is, but it isn’t. The layer of Unreal over the C++ makes it almost a different language entirely. Switching to C# isn’t going to make programming easier on Unreal, because the ‘Uneral Layer’ will still be overtop the C#. If people want to spend their time making a wrapper, fine, but quit bothering Epic with these request. Their time is better spent doing QA on the features we need and have, rather than catering to a crowd who refuses to learn a industry standard language.

And I wish there would be something like a primer or a fundamental documentation on UE4.
A little tour of the code that really starts with the most priimitive classes that are derived directly from native C++ classes.
Having a little tree that illustrated the class hierachy would be most helpfull :slight_smile:

The fact that C++ is a"industry standard language" and other languages are not is a very subjective remark, not every body would agree with that.

C++ in Unreal makes me think a bit about Qt, and I am glad to see that they made efforts to improve usability of C++ coding, however it would never reach the ease of use of C# and all the nice syntactic sugar, ever, there is not point arguing about that.

Thanks Mike I’m really pleased to hear from you guys, and to hear that you are also listening to want users want.

Here a few comments to what you said…

Fair enough to defend Epic’s position by saying “if you want it just do it”…

However I find this argument a bit too easy IMHO, then why would Epic keep on implementing new features if users or 3rd party could develop it instead…

Open-sourcing is great but you guys should not rely on this too much for such important features and between you and me, we both know that if it’s not officially supported by Epic, scripting solutions are quite unlikely to reach a very mature state, and users will never use it.

Well that’s a step forward…I’m glad to hear that you are open to scripting in UE4. I agree that C# should not be prioritized over more wanted scripting languages.

What about creating a community-based poll in order to decide which language should be supported in the future ?
And the most favorite language would then get Epic’s attention for a built-in support (A real one, not like the LUA plugin…).

Well that’s interesting news…tell us more :slight_smile:


I can answet that, qith question. Did you saw game made by Epic which is done fully in blueprint, except Tappy Chicken ?
While blueprints are awesome, nice, and it’s best thing since sliced bread(no arguments!), I don’t think most people even consider making serious game fully in them.

As an end point they are great (connect few nodes, like 4-6 and buf! you have new gameplay element, which just call to pre setup C++ interface) or as for prototyping, I can hardly imagine someone making fully big game with them.

Just because there is hammer around laying, doesn’t mean you should use it to kill flies.

The same IMO is going for other non C++ languages. With even less benefits. Blueprints are fairly easy to understand by virtually anyone. While written languages, are not. For me it doesn’t make any difference. But people who never wrote line of code, doesn’t care if it C++, C#, Go, Visual Basic. It’s the same arcane magic beyond understanding at first glance.

Aside from that. There is no real reason to implement anything else. Hardness of C++ (especially in wrapped version in UE4) is mainly based around prejudices, not any facts. Look, there are people around forums, who are artists, and yet know how to code in C++ ;).

They add features, that most people want(and what they need). As you can easily judge, people around don’t want scripting integration from Epic. More over most people seems to be clearly opposed to such thing.
Because it would take resources, which could be used to add new features, that are actually needed, or improving existing ones.

C++ API in UE4 is great and I like it very much, but there are some features just impossible without some form of scripting on mobile platform, like hot-code-updating without going through AppStore. Nearly every online game in China is using this technique to facilitate super fast iteration (commonly 1 to several updates everyday, which is impossible with the slow review process of AppStore), so having this feature is crucial to be competitive on this market. For now the market is dominated by Unity, I’d be very happy to see UE4 to take over.

Blueprint is great in small scale scripting and prototyping, but I don’t see the benefits in real production of complex games, the graphs in TappyChicken are way too CRAZY and FRIGHTENING for such a simple game!

Well, I have quite a background as a Delphi programmer and still C++ is somewhat “weird” to me.
Take for example the string handling. Im used to have a string as a basic data type. Now I started reading through the C++ primer, but still cant figure out how to concatenate strings mixed with integers (and storing it in a string variable. im not talking about cout << “text” << x << “more text”; here)…
So C++ is perhaps not the most intuitive language.
One reason why so many people like C# is the fact that it borrowed some nice stuff from Pascal, syntax-wise and also conceptionally.
Today I wouldnt use the original Turbo Pascal anymore either, but Object Pascal is equally strong as C++.
So introducing C# would offer a compromise between the two worlds.

Can you then recommend good reading material that explains the specific parts that Unreal introduces to C++?

I disagree. You want them to spend time integrating C# which takes time away from relevant development, there would have to be a good reason why they should put their time into letting you use C# over C++. I don’t think there’s a good reason.

FYI in your original post you are already debating this.

As a programmer you need to adapt and learning C++ in EU4 will benefit you in the end.