[Tool] UDK T3D to Unreal 4 T3D Tool

I ported over a modular buildingI made originally in UDK into Unreal 4, and the results where fantastic.
However I had to manually place every actor again to recreate it, wasn’t that big of a deal since the building was not that complicated.

As I wanted to do the same to my CBC building. There was no way I was going to place over 2000+ actors again.
So I wrote a tool orginally in php to convert UDK’s T3D into Unreal 4’s T3D, Is now a stand alone program written in C#

v2.0 Standalone

Download .exe Version 2.0
Supports converting the following actors

  • Static meshes (Lightmap UVs, overridden materials)
  • Skeletal Mesh actors
  • Interp Actors
  • Kactors
  • Lights (brightness, color)
  • Cameras
  • Decals
  • Particles
  • Audio
  • Exponential height fog

v1.0 PHP (only works with static meshes)
Online version link 2

  1. You sill need to export all individual meshes & textures from UDK, and import/set them up inside of Unreal 4.
    (with a lot of work, it would be possible to write a tool to convert materials exported as T3D made in UDK, into unreal 4)
  2. Once they are in the Content Browser, you can copy the actors inside of UDK, use the tool to convert the output, then paste into Unreal 4.

There is still a lot of manual labor involved while re-importing assets into Unreal 4, but this tool is the first step in reducing the work it takes porting from UDK to UE4

Awesome!, Good job. I think tools like this would be very useful for the community.

thats very nice of you Matt3D, but have you considered to scale difference between UE3 and UE4.
i don’t want to get you down but its a problem i found during the beta , the scale will affect all parts from lightmaps - physics - collisions and who knows what else

So far I haven’t noticed an issue with the scaling of objects. However you might be correct as I am just using both engines as renderers for my art, and there may be issues I’ve yet to encounter related to gameplay.
As long as the meshes you reimport into UE4 are of the exact same size they were in UDK. The tool places them in the correct location, rotation, and scale.

However if there are issues related to the scaling, I could make the tool modify the values to fix them. For example I’m already having to convert the rotations. It wasn’t a simple copy/paste of the values in the right place because
UDK stored rotations in it’s own unit format (where 65536 was 360 degrees), my tool converts the value into normal degree rotations which is what UE4 is using.

I just tested that if you parent every mesh that got ported over, and change the parent’s scale. It re sizes everything correctly. That’s how you can fix any scale issues.

if i had realised that i would have saved myself a lot of time, oh well there done now, but that is good info for others


Awesome doesn’t quite sum that enough, that’s “awesome turbo” :slight_smile: :cool:

Hello Matt, your tool would be a huge help to me as well. The problem is that I cannot open Would you include a download link either on your main site where you mention the tool, or here? Thanks, Steven

I’ve reuploaded the tool to a different host

Unfortunately it is written in PHP, therefore must run as a website on a server. When I set out to start the tool I knew off the top of my head I could do it in PHP, It had been too long since I had complied a program in C++ or Java.
However I will look into making an offline version.

Thank You:)

Matt3D, this is a great idea for helping the UE3/UDK community move to UE4. Thanks for releasing this!

Thanks Tim! It’s worth the move to UE4 thanks to all the amazing improvements Epic has made.

I’ve completed the move of my CBC building from UDK to UE4 using my tool, now just to make some finishing improvements to it. You can compare theses new shots with the previous one from UDK in my first post and on my website

And finally as per UnWheelModeller’s suggestion, I’ve re-created the tool using C#/Visual Studio express so now you can download it, I’m also willing to share the source code if anyone is interested.

Also released a T3D Converter that supports bsp brushes for UE4 ideal for maps convertion
Supports convertions from UE1,UE2,UE3,UDK T3D TO UE4
Supports Scaling

Thanks again Matt3D, I have downloaded your tool!

Thank you so much for this Matt3D. You’re a true gentleman! We’re working on quite a bit project and might have to go from UDK to UE4 so your tool is a lifesaver!

Thank you, this worked flawlessly.

Protip: If you’re getting an Index error your object may be too far (off the grid far) from the origin.

Here’s an update and some news.

Version 1.1 changes:
-Two check boxes for scaling the location and drawscale values by 2. This is an alternative rather than parenting everything and scaling the Parent by 2 in order to fix the size of assets.
-Any and all Material Overrides are supported as well as Overridden Light map UV’s
-Bug fixes, now you should no longer be getting index errors such as when actors having missing static mesh paths

I’ve received a commission to improve the tool, and have already implemented the following features for version 1.2, This version will be released as a paid asset on the Unreal Marketplace when it launches.

  1. By providing the path to your UE4 “Content” folder, the tool will dynamically search through the assets and match by name and use the found path instead of converting the UDK path. This allows you to have the assets in any location, the only requirement is that they have the same name
  2. Support for the following actors added:
    -Lights (All types except for Skylights and pickup lights)
    -Skeletal Mesh Actors
    -Interactive Foliage Actors
    -Fractured static meshes
    -Apex Destructible actors
    -Exponential Height fog

Although UDK and UE4 both support exporting materials out to T3D. The functionality for re-importing a material as T3D back into the engine is broken in both versions. Therefore there’s no easy way to port over materials yet, unless Epic fixes this.
SpeedTree actors are a potential addition to this tool, however I do not have a subscription right now for SpeedTree for UE4, which I would need in order to find out how they are implemented.

Let me know if there’s any other actors I’ve missed that I could potentially add on.

Awesome, could you add support for importing the vertex colors? I noticed they are included in the copy & paste text in both UDK and UE4. I’m tempted to write a script to convert myself but if you could include it in your tool that would be awesome! Let me know if there is anyway to buy it sooner too as I could really really use it.


I’ll look into it tomorrow/this weekend, shouldn’t be a problem. We can work something out immediately if you want access to it, Haven’t settled on a price but I’ve been thinking $5 or $10.
As you may of noticed the Marketplace is taking early submissions but external tools like mine aren’t allowed yet, and I don’t know if they will ever be.

It’s been suggested that I remake the tool as a UE4 plug-in, and well I’ve wanted to dig into the source code for unreal for awhile now, but am not that Familiar with C++. I’ve been using Unity C# for awhile now and have written a bunch of editor tools that I would like to recreate in Unreal 4. The tool itself is also written in C#.
I would rather not have to re-write the whole tool again in C++ (although I have no idea what (if any) rewriting would be required)

I don’t even know how easy it is to extend the editor or even what’s possible, I asked a question of how to get started with scripting the editor. Blutilities seem to be half implemented because they were a “friday experiment”, plus with any visual scripting engine you are limited by it’s implementation. I couldn’t figure out how to get or provide selected assets so that I could do something with them. I believe that’s because Blueprints are all about programming game logic, and not about accessing the editor.

So for now the tool will have to remain an external tool.

I’ve updated both the currently released version (1.2), and the forthcoming paid (2.0) version to support vertex colors.

However, a note on Vertex Colors: While the tool does support the porting over of Static Mesh vertex colors. There is an issue that may prevent them from working.
The import/export process of meshes is sometimes not 1 to 1. A mesh that is re-exported out of UDK may not have the same structure as it actually does inside UDK. This means that although the Vertex color data is there the T3D script and is converted, it won’t appear up on the UE4 mesh because technically, it’s a different mesh now.
In order to fix this issue, You can try re-importing the mesh back into UDK. This means both engines have the exact same data to work with, then copying the actors.

I’m currently exploring my options on how to step a way to purchase the 2.0 version.

Does this support material import?