UE4 to UE5 Map Migration Guide

UE4 to UE5 Map Migration Guide

Introduction

This guide aims to help you transition your previous map from UE4.27.2 to UE5.3.2. It includes necessary steps and changes to the workflow to minimize the amount of work needed to port your map.

1. UE5 Template

Download and Install Unreal Engine 5.3.2: https://www.unrealengine.com/en-US/download

Download the following new UE5 Template and extract to your preferred location: https://www.nexusmods.com/readyornot/mods/1384

2. UE4 Map Preparation

Nearly all of the previous work you have done can be ported over with exception of any Blueprints from the old Template.

The following should be replaced (or deleted) with placeholder engine meshes so you can easily replace them after the migration:

• Landscapes (DELETE! You will need to remake these in UE5, but using a heightmap from your old Landscape can save you some time)
• BP_Doors_Reap
• BP_AISpawns_Reap
• BP_BreakableGlass_C
• FMOD Events
• RosterScenarioSpawner (Delete)
• WorldDataGenerator (Delete and no longer needed)
• BP_SpawnManager (Delete)
• BP_CoverGen (Delete)

Ready Or Not Audio Volumes, Portal Volumes, Room Volumes, CoverGenOverride Volumes can remain as they are still the same actors. If they do not work convert them to a BlockingVolume (Under Actors tab in Details) temporarily to convert back after migration. Sound_ParameterTransition_V2_BP_C Blueprint can remain but it is likely you will need to reassign everything.

You did organize your map already into nice folders in the Outliner right????

3. FModel Setup

We no longer are using UModel anymore as it is no longer supported for UE5.

Download FModel: https://fmodel.app/

Download Mappings file: Mapping File

BEFORE PROCEEDING: Remove ALL mods from your game. FModel will load them and cause issues and materials may not load properly.

1. If first time using, click the arrows for ADD UNDETECTED GAME and select C:\SteamLibrary\steamapps\common\Ready Or Not\ReadyOrNot as your directory AND press the + button.
2. Select the UE Version to be GAME_UE5_3 and press OK
3. Go to Settings and under General > Advanced, Enable Local Mapping File and set the Mapping File Path to the downloaded Mappings file. (This will allow you to view the cooked content in FModel)
   • OPTIONAL: In Settings > Models > Mesh Format, change it to glTF 2.0 (binary) so you can export static meshes
   • Take note of your Export Directory

You will need around 100GB free for the next part, we will be extracting the game’s cooked assets so they will show up in your map, and unfortunately require a lot of space.

1. On the Archives Tab, select all the .paks from the game and click Load.
2. On the Folders Tab, navigate to the ReadyOrNot > Content folder and right-click and select Export Folder's Packages Raw Data (.uasset). This will save all the cooked content from the game and might take some time.

Once complete move onto the next step

4. Copy Cooked Content to your Project

1. Close the new UE5 Template before continuing.
2. Navigate to where FModel exported the cooked assets and copy the Content folder (or drag if storage space is limited) to your Project’s Content Folder.
   • This INCLUDES the shadercaches.
3. DO NOT overwrite any files if prompted! Just skip these files. If you overwrite them, you will need to start again from scratch with a new Project.

All the game’s assets should be available in the project now, including working Materials, Decals and Particle Effects!

Optional: Importing FMOD Events

If you wish to hear the QSM or ambient sounds follow these steps, there are placeholders if you do not wish to make your project folder any bigger:

1. Navigate to C:\SteamLibrary\steamapps\common\Ready Or Not\ReadyOrNot\Content\FMOD and copy the Desktop folder.
2. Navigate to your projects ...Content\FMOD folder and paste the Desktop folder here.

5. Migrating your UE4 map to the new UE5 Project

1. Make sure the UE5 Template is closed before continuing.
2. In your UE4 Project, right click on your Level and select Asset Actions > Migrate
3. DESELECT everything first. We do not want to copy ANY of the old Blueprints or Cooked Content
4. Navigate to your Mods > YourUsername section (where your Map SHOULD be located) and ONLY SELECT these files (or any Files YOU created and want to carry over). Hit OK.
   • You do not need to copy over any previous contents from Mods > Reap
5. In the new Window, select the location of the Content folder of the UE5 Project and proceed.
6. Once complete open up your map in the UE5 Project and inspect the result.

If you Level wont open or crashes the Editor, I would recommend taking a more manual process to migrating the map. Following up to step 5, instead create a new Level and manually Copy-Paste assets between Editors. DO NOT copy anything RoN Specific this time. Make sure not to have any Landscapes either.

6. Fixing Issues and missing Assets

Fixing Inverted Collision from Migration

There is a serious bug that occurs when migrating from 4.27 to 5.3, any custom Static Meshes you bring into the project will have their collisions Inverted. Thankfully VOID also encountered this and helped with the solution (major thanks to killowatt & RareKiwi for this)

To fix this:

1. Select all Static Meshes that you migrated in the content browser.
   • Easiest way to do this is just select your mod username directory and filter for Static Meshes
   • If you turn on Player Collision view mode, you will see all the normals on the collisions of your assets are flipped if placed in a level
2. With the meshes selected right-click and select Scripted Actor Actions > Collision Fix Up.
   • This will iterate through the meshes and correct their collision.
3. Verify they are correct in Player Collision view mode.

Alternatively, you can do the same steps on selected actors within a Scene by right-clicking them and selecting Scripted Actor Actions > Collision Fix Up

Reassigning NULL Static Meshes

If you have followed the steps up to this point, the map should be mostly still intact. Most of the cooked assets from UE4 have remained in the same location in UE5, but now you can also view their materials!

There is mostly likely going to be a few hundred missing cooked assets due to files being moved by VOID with the update. To identify what is missing, click Build > Check Map.

All missing assets should say “Static mesh actor has NULL StaticMesh property”. Provided you haven’t renamed any files it should be pretty straight-forward to find the same named asset in the Content Browser and replace them in the scene. Unfortunately there is not an easy/fast way to do this, so brew a cuppa and get to work.

If you do Step 5 before Step 4, ALL of the references to previous cooked contents might return NULL, instead of just a few. Just to be safe, make sure the cooked content is in the project before Migrating or Copying

New Basic Map Requirements and Changes

Do not click Build All, currently doing so will lock the Editor in “Building Texture Streaming” and will require you close it via Task Manager. You unfortunately have to Build Geometry, Paths and Lighting separately now.

Things mostly remain the same, however the following changes to workflow are needed to make sure that the map runs correctly:

• Set the Level Blueprint Parent Class type to Ready or Not Level Script
  • Not doing so will result in things not working properly, specifically objectives, spawns and QSM/FMOD
• DO NOT set ItemData datatable in the Item Data field of the Blueprint Class
  • If included, cooking will fail - there is a dummy ItemData in the project that shouldn’t cause this. But better safe than sorry.
  • REMEMBER TO REMOVE IT after you have migrated from UE4 - it may still be assigned.
• Add a RosterScenarioSpawner actor
  • Without it the map will crash on Level load
• BP_SpawnManager_V3 is required now (located in Mods > Template > Blueprints)
  • Without it no AISpawns will not work
• Make sure that all BP_AISpawns_Managed have “Managed” assigned to their Details > Actor > Tags
  • Without it no AI will spawn even with the Spawn Manager
  • This may happen if you Right Click > Replace Selected Actors with on placeholder actors after the migration.
• Add a BP_CoverGen actor
  • Without it AI won’t really move or do anything when engaged in fights
• Multple PlayerSpawns are no long spawn the SWAT AI on them; they will all spawn on your PlayerSpawn. You only need 1 PlayerSpawn per actual Spawn Point (set in ModLevelData Table).
• QSM Changes

7. New Cook & Pak Method

Cook and Paking remains the same process as before but there are 2 important things that have changed.

Updated .bat Pak file

You NEED to use the new updated .bat with the UE5.3 files (do not just edit your existing one): More Info

@setlocal ENABLEDELAYEDEXPANSION
@if "%~1"=="" goto skip
@setlocal enableextensions
@pushd %~1
(for /R %%f in (*) do @set "filePath=%%f" & set "relativePath=!filePath:%~1=!" & @echo "%%f" "../../../ReadyOrNot!relativePath!")>"%~dp0/filelist.txt"
@pushd %~dp0
::-compresslevel=4 for Normal, -compresslevel=-4 for uncompressed hyperfast paking
.\UnrealPak.exe "%~1.pak" -create=filelist.txt -compress -compressionformats=Oodle -compressmethod=Kraken -compresslevel=4
@popd
@pause
:skip

Delete Global ShaderArchives

Cooking a map now produces Shadercaches, there is an extra step needed for cooking to prevent them from being cooked but still provide the necessary ones for your materials and .uassets:

1. Before you cook, go to Edit > Project Settings > Packaging, and disable Share Material Shader Code - BUT DO NOT RESTART THE EDITOR!
2. Cook your map as usual.
3. When cook is complete, re-enabled Share Material Shader Code.

The above method should be used if you are sharing/distributing your final map .pak. If you include shadercaches that aren’t just your own materials than we might run into conflicts.

For faster development however - you can just cook and copy the Content folder as usual without always needing to disable/enable Share Material Shader Code. HOWEVER if you include files named similar to ShaderArchive-Global-PCD3D_SM5-PCD3D_SM5 then Ready Or Not will crash on launch. So before you Pak your map, make sure you delete the all the ones named ShaderArchive-Global... (you can leave the others) from the Content folder. If you delete the other ones some of your custom materials may not render properly in-game. However, if there are some issues with your own materials, also try deleting the files named like ””

As a final resultIf you are still having issues also try deleting the ones named:

JUST REMEMBER TO DO THE COOK METHOD MENTIONED FIRST FOR DISTRIBUTION!

Cool stuff in the New Template!!!!11!!1!!11

• In Mods > Template > Levels there are 2 Maps:
  • RoN_Template is a barebones map that is the absolute bare minimum to get a level working.
  • RoN_ExampleMap showcases how to build a map. It has information on the Spawn Manager, Objectives, QSM and working with the FMOD, along with some other interesting bits of information
  • In general the layout of information and Blueprints we actually use is a lot cleaner now.
• We now have the Actor Palette Plugin enabled. This allows you to open up a level under Tools > Actor Palette. Doing so allows you to drag and drop Assets from the window into you map with ease! Very cool~
  • There are a bunch of maps in Mods > Template > Levels > ActorPalette that you can load to test
  • Warning: These maps require a LOT of memory as they are loading essentially all the usable props from cooked assets. I would not open Palette_MASTER unless you have a strong PC.
• We can now create custom doors from our own DoorData DataTables (and there are tools to help copy over Door and AI rows from cooked assets courtesy of RareKiwi).

Known Bugs

• Double doors do not seem to work as double doors after the first load of the game, this seems to be an issue with the World Generation that is out of our hands for now.
• When saving or opening a Level, the editor will ask you save changes to BP_Makarov_2Handed_AnimData and BP_Tec9_AnimData, you can ignore these. Saving wont break the project if you do.

Credits and Thanks

Kingly credits need to go to RareKiwi for his dedication to updating the project and previous Blueprints. It is no small thing to say that without him, we would not have the new Template.

Additional Credits to KITT, StenTheAwesome, Delta, Reap, The Real Sourc3 and to the beautiful VOID Interactive Devs (killowatt, Zack, QuantumNuke and Hunter).