Question regarding switching versions during development

Hello, I am brand new to Unity and I'm currently just messing around with the software to learn the particle fx engine and lighting. I was curious how does Unity handle content or builds for games that was created for old versions? Hypothetically if I were to fund a successful kickstarter and we use the current version of the engine, and a few months prior to our official release a major new Unity version is released, is it a lot of work to transition into the new version of the software to include the new features? I'm hoping its a very easy transition similar to working from photoshop CS3 to CS6 for example. I'm not a coder, so I don't know if it would require months and months of recoding stuff, etc.

A specific example would be if I want to take advantage of the new rendering and lighting engine in Unity 5 would that be a huge time sink if I had previously been working on Unity 3.5?

 

I'd say definitely a lot of work, if you take 3.5 to 5 as an example. New particle system (Shuriken), new animation system (Mecanim), (and looks like a new audio system) means you have to redo some things if you used the old systems.

Code-wise, certain parts of Unity change: perhaps a function got renamed, maybe some of its parts got re-ordered, maybe some old, now-irrelevant part of the code is removed (i.e. deprecated), etc. so you have to update your code just for it to work again.

Just take note though this is if we are talking about major version changes. If it's something minor, like say, 4.5.0 to 4.5.2, chances are, there's little to no change needed from you.

Look at the version release logs to find out for sure. You'd need some technical know-how to make sense of that, or get someone to "translate" it for you.

One good practice is to make a backup of your project before you upgrade, if ever you decide to do so. So in case things break, you still have your old copy that's sure to work in the old version of Unity.

 

If you use a version control system then this is a non-issue. If you update and it breaks, you just revert to the version before you updated. That's not to say that you shouldn't also back up, but you should do that to your version control repo. Or, some version control systems can be a pretty effective backup system in and of themselves if you keep the repo off-site.

Ok, I'm done.


In regards to the question in the OP... it really depends on how your code is written. Typically going forward with minor versions it's no big deal at all. I've successfully moved a couple of 3.x projects to 4.x with zero work, but I've had a couple that did need some, too. There's no telling for 4.x to 5.x until we can get our hands on it, though there's a few things to note such as Beast being replaced with Enlighten and updates to the scripting API like the convenience component accessors being stripped from MonoBehaviour. Things like this may require manual updates, or it may be stuff that Unity can automate in the transfer. Though I would indeed think that jumping more than one major version might be more of an issue.

Out of interest, why jump from 3.x to 5.x? You need Pro and already have some old licenses?

 

thanks for the feedback guys. I was only using a hypothetical example with the version I mentioned. I purchased a training course a few years ago which covered unity 2.5 or a version of 3-- (not sure off hand) and I'm a bit out of practice so I'm just coming back to it. I have downloaded the free version of the current version to brush up on things, and I know there are certain things coming in the next big update that I'm very interested in using such as enlighten and the audio engine, but I didn't want to have to recreate a bunch of work over again if I could avoid it. Maybe it's a case by case basis.

 

When you go little by little, it's usually no big deal. Unity 5 will change a lot of stuff though (which is good).