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Unreal Replication In Spatial



In terms of replication between clients, is the typical unreal replication mentality out the window with spatial? IE does everything need to be done through setting components in order to replicate between clients, such as position, rotation, actions (shooting, projectiles, etc)?


Hi jro,

Currently, UnrealSDK relies on a distinct API that communicates through generated components as you mentioned.

However, if you’re looking for a more “native” workflow, we have good news! We recently announced the Game Development Kits, and with the SpatialOS Unreal GDK we plan to enable seamless interoperability between Unreal’s replication and SpatialOS.

We currently don’t have a release date for Unreal GDK, but we will continue to share more about it in the near future. Stay tuned :slight_smile:.


Thanks @giray - so with the upcoming GDK I’m assuming there will be a way to convert existing projects built on Unreal’s networking workflow without too many changes? The GDK sounds great as it would be nice to focus on the game then trying to learn a new workflow from scratch (spatial).

Can you tell me the planned Unreal version support for the GDK or will 4.17.1 still be the focus?


With the new approach, porting an existing game will indeed be significantly easier. This was one of the primary principles that guided the Unreal GDK architecture.

Note that an API that faces SpatialOS, with its distributed nature, has to deviate at times from a single authority API like Unreal’s. Thus, you may have to think about how you design your game with this new paradigm in mind. But porting itself should be a fairly straightforward process. We will share more with the community as the design of the GDK solidifies.

We haven’t finalized which minimum engine version Unreal GDK will support, but the plan is to maintain support for several of the latest stable versions. I can say that support is more likely to start from 4.19 and not 4.17.


Sweet thank you for the info! I know nothing has been released yet but publicizing any design principals (unofficially) that “might” make porting easier in the future would be a great blog post :slight_smile:


We agree with you @jro, hope to share early progress and design very soon.


We stopped looking at SpatialOS for Unreal many months ago when it became apparent that it was going in the wrong direction to suit our needs, but this new discussion of the GDK concept has intrigued me.

I have a couple of questions:

Will support and development for the current Unreal SDK be dropped in future? (Not relative to us but certainly to others.)

What is the approximate timeframe for a usable GDK? Three months? Six months? One year?

I am not asking for a deadline, simply a loose projection. I am sure that you already have this projection internally and if you actually want to generate any interest from the at large Unreal community, then my suggestion would be to be more forthcoming.

There is actually a significant though small Unreal MMO dev community, part timers, hobbyists, and micro studios for the most part, who it is clear would be the primary market for a SpaltialOS Unreal solution. My gauge of this community is that it has become jaded by “announcements” that never bear fruit and that it will not be quick to embrace vague potentialities. If you want to engage this community, then you should avoid the standard PR and Advertising practice of never saying anything significant.


then you should avoid the standard PR and Advertising practice of never saying anything significant.

Which seems to be exactly what they are doing, along with vague pricing and other nonsense.
Very off putting as an eager potential customer.


Hello there @Blinn,

To give a little bit more context here and share some extra information that you might have missed:

  • We have announced our Game Development Kits (GDKs) for both Unity and Unreal.
  • The Unity GDK has been the subject of a more in-depth technical blog-post and has been on GitHub since mid-June in pre-alpha state. It is being developed right in the open for you to see and give feedback.
  • The Unreal GDK implementation has also been discussed. It will also appear on GitHub in early August in pre-alpha so that you can follow it’s development.
  • We have announced Platform SDKs so that you will be able to easily script your workflows with our cloud services both while you are developing and when your game hits production. Initial pieces of this will be landing in September as described in the linked blogpost.

There are other features and improvements on the way as well and we will be communicating about them when this makes sense.

Although we are tagging the GDKs as pre-alpha because they are not yet suitable for full-scale development it is certainly possible to use them for prototyping: we have already being do so internally via small-scale game-jams to ensure that the resulting workflows are pleasant and effective in their use.

If you have any concerns about specific things or “nonsense” (:wink:) that we have put forward in our announcements or communications please do not hesitate to raise these. As always we need to balance things between only notifying you the day we deliver features and giving you enough awareness of what is coming further down the line to give you an idea of our roadmap. In my experience there is however no such balance that satisfies every single one of our users.

Kind regards,