Patch and DLC support


As I’m coming up empty when looking for documentation on regards to the currently available patch and DLC workflows, I’ll ask here.

What is the way UE4 supports post release patches?
What is the way UE4 supports DLC?
We’ll ship on Windows, PS4 & XBoxOne, are there differences in patching from the UE4 side that I should be aware of?


Hi Simon,
Currently we have little game side patching support, except for our launcher which only works on desktop platforms.
It is on our agenda and we do have a plan going forward I don’t have any release dates as of yet.
The plan is:

  1. When you release the game it is suggested (for small diff size) that there is a lockdown on byte code serialization code paths. No engine version should change, as this will make your previous cooked content broken
  2. Keep cooked content from released game
  3. When patch is finished, cook new patched content
  4. Either a new tool or perhaps part of the unrealpak tool we will diff each package against original and generate a new pak file.
  5. Run time mount both the pak files

Most of this is in place, there is at least one known issue, currently the cooker isn’t deterministic between cooks, also the diffing of cooked packages isn’t in place yet, I don’t have a release date for either of these.

The user created dlc solution is still being worked on almost all the steps are there as of 4.8, however the process is subject to change

  1. Release game, editor, cooked content and also asset registry for cooked content
  2. User creates content
  3. When the user wants to release they cook against the released asset registry which culls the released content from their local cook, if you want to support forwards compatibility then this needs to cook versioned content
  4. That is then placed into a pak file
  5. The user releases the pak file as dlc
  6. Run time game reads both source pak file and dlc pak
  7. If new version of main game is released then new cooked content and asset registry is provided
  8. Reading old dlc will be allowed through the use of versioned cooked content.

Thank you for the reply,
Are there any guidelines we can use for setting up DLC maps and content so we stay compatible with your plans? In UE3 each DLC had it’s own directory and I remember seeing a similar remark for internationalization for UE4 somewhere. Will the documentation also be updated with the 4.8 preivews? I am looking for information like: Will we be able to update existing assets maps or .ini files using theses DLC paks? Versioned vs unversioned content ramifications. so basically the whoel documentation on that :slight_smile:

If you have no plans to update that should we start posintg all these questions separately once the preview is available?

Hi Simon,
DLC Cooking code path will be implemented and working for 4.8, it is still subject to change however you will be able to make dlc paks which can be used in main game.
Our patching system has pending tasks which have yet to be pinned to a release. When they are finalized and tasks are complete the documentation will be updated.

Thank you.

We now have release and patching documentation: