Common Questions and Answers

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Hey everyone! I know that the AnswerHub seems like it's flying by at a mile-a-minute, but you can help out just by jumping on common issues. This is a list of commonly asked questions that are currently popping up. Think of this as a FAQ that will be updated and changed as new trending questions arrive.

Legal and Licensing

Q: I have a small team and want to know how the license works for us

A: The 5% royalty is per-product, and doesn't depend on the number of team members. You should appoint one team member to be responsible for financial duties - receiving App Store revenue, paying royalties, distributing profits among team members, etc.

Q: Can you use the content in the marketplace for commercial use ?

A: You can use all of the free Epic content in the marketplace commercially in any games you build with UE4. This includes all of the content residing in example projects. For example, all of the weapons, meshes, sounds and materials in Shooter Game. Tappy Chicken even!

Q: If I learn a cool trick, design, algorithm, pattern, etc. from UE4 and implement it in my own engine, is this considered copying?

A: Learning algorithms and ideas from Unreal and then independently writing a new implementation elsewhere is fine. Copyright law covers the code but not the underlying idea or algorithm. Generally, a good process is to very clearly separate your learning of techniques in one code base from your implementation of them in another. If you find yourself looking at Epic code in one window while writing your own engine in another window, you're in a danger zone where you risk copying the code or its structure. If you do it that way, you risk creating a copy of our code under copyright law, even if you choose different variable and function names. In the case of UE4, this means the difference between owing a royalty for using Epic code and having independently authored code.

Q: How many computers can I install UE4 on?

A: “There is no limit to the amount of systems you can install the engine to. You're restricted by the EULA only in making sure that there is only one person per subscription.”


Q: Is free content free to everyone on the marketplace?

A: Yes!

Q: Can you use the content in the marketplace for commercial use ?

A: You can use all of the free Epic content in the marketplace commercially in any games you build with UE4. This includes all of the content residing in example projects. For example, all of the weapons, meshes, sounds and materials in Shooter Game. Tappy Chicken even!

Hardware and Software

Recommended Hardware

Q: My system is just below required hardware, is that ok?

A: The Unreal Editor can run on some lower spec systems, but it is most likely not going to be a very good experience. To cope with the low resolution, you can enable small icons, and use the editor's tab system to combine the tabs on the left and right sides of the screen together. Be prepared to switch tabs frequently.

Also, for laptop use, it's very beneficial to buy a mouse with two buttons and a wheel rather than using the trackpad. The required system specs there are the minimum needed to run with a good experience that we can recommend and endorse. It will often run on machines below these specs, but less pleasantly.

Q: What about Linux?

A: We have partial Linux support in the code base - working towards Steam OS support. You can subscribe and download the source code, and try and port it completely to Linux or any other platform you like. Let us know if you do! You can even push any improvements you make back to us (if you want). And you can absolutely publish your game (in compiled form - you're still bound by the license not to release our source code publicly.)”

Q: How can I change default location of Unreal Projects?

A: We currently don't allow you to change where the Unreal Project's directory is located. We are working on a fix to this issue. Until the fix can be implemented, a work-around can be found on this post:


Q: Does UE4 support DX9? What about WinXP?

A: Unreal Engine 4 supports DX10 / OpenGL 3.3 and above, but it does not support DX9 at this point. If you are looking for DX9 support due to DX10+ not being available on Windows XP, then OpenGL might be a better route to get higher end rendering features.

Having said that, we currently don't support Windows XP, but have tentative plans to change that down the road. There are some traces of support in the source if you or someone else in the community want to expand upon that. A complicating factor on the technical side is that the version of the Windows SDK we are using is not compatible with Windows XP. Luckily the extra functionality we use in the newer Windows SDK is not relied on for anything game critical.

Q: Will UE4 support DX12?

A: Yes. Epic will be working closely with NVIDIA and Microsoft to create a world-class implementation of DX12 in Unreal Engine 4.


Q: Where can I set the default user interface language?

A: The only way to force a particular culture always that I know of would be to pass in the culture to use on the command line. Which I believe is Culture=en if you want to force it to be English.

Adding Culture=en to C:\Program Files\Unreal Engine\Launcher\Engine\Config\BaseEditor.ini may also work.

This work-around does carry the potential to be responsible for data loss, so you may wish to back up projects before moving them.

Your already downloaded content should load correctly from the new location.

Q: Are there any advantages to making map objects out of brushes vs. making them in an 3D program and importing them?

A: Brushes are generally meant for prototyping layouts and for constructing very simple environments. They don't perform we when scaling up to high-polygon environments. Static meshes are the recommended primitive for building larger and more detailed environments. The levels in Infinity Blade and Gears of War are nearly 100% static meshes. Of course, the downside is that building a level with static meshes requires a large library of meshes or a significant effort modeling and UV mapping them in an external tool like 3D Studio Max, Maya, or Blender.

Q: Why can’t I use int64 (or uint32, or int16) in Blueprints?

A: This is a result of legacy code for Kismet in UE3. Numerical data types were restricted in Kismet in order to simplify its use, and the same data types are currently available in Blueprints (uint8, int32, float). All other numerical data types are fully available to use in C++, but cannot be used with Blueprints. There is some discussion going on internally about exposing the larger numerical data types (eg. Int64 and double) to Blueprints as well. Unfortunately this change would be a fairly large task, so it is unlikely to happen soon.