External Content Development Standards

Image assets used in Materials to apply to surfaces or drawn on-screen by the HUD.

Choose your operating system:

Windows

macOS

Linux

The following list should be considered construction standards for Unreal Engine content. Although your personal projects may use any standard that you like, any content that you wish to distribute should follow these standards.

Static Mesh (3D Models) Standards

  • File Format: FBX.

  • Scale: 1 Unreal Unit = 1 centimeter (cm).

  • Origin (pivot): Should be located at a spot convenient for placement, generally at the center bottom of the object.

  • Orientation: All models should have their forward dimension facing in the direction of the positive X-Axis .

  • UV Layout (Texture coordinates): Meshes may use overlapping UV patches to maximize texture usage. However, they should also have a separate UV channel, specifically for light maps, in which all UV patches are uniformly laid out without any overlapping. Note lightmap UVs can be generated within the Static Mesh Editor , though creating them in your 3D package will provide extra editability.

  • Materials: All meshes should have a corresponding Material applied to them.

  • Vertex Normals: If the visual quality of your model requires custom vertex normals (a.k.a. Smoothing Groups), make sure those are exported from your 3D package and that you import them into UE4 when importing your content.

  • Max Vertex Count: For mobile devices, each mesh should have a maximum of 65,535 vertices. On other platforms, such as PC, you are limited by console and should test accordingly.

  • Collisions: Wherever applicable, meshes should have collisions applied to them. See the Static Mesh Collision Reference for further details.

Skeletal Mesh (Meshes animated via a skeleton) Standards

  • File Format: FBX.

  • Skeleton: All Skeletal Meshes should have a corresponding compatible Skeleton asset. Skeletal Meshes with the same bone hierarchy may share a Skeleton asset, however.

  • Scale: 1 Unreal Unit = 1 centimeter (cm).

  • Origin (pivot): Should be located at a spot convenient for placement. For Skeletal Meshes, this is typically right between the feet.

  • Orientation: All models should have their forward dimension facing in the direction of the positive X-Axis .

  • UV Layout (Texture coordinates): Meshes may use overlapping UV patches to maximize texture usage.

  • Materials: All meshes should have a corresponding Material applied to them.

  • Vertex Normals: If the visual quality of your model requires custom vertex normals (a.k.a. Smoothing Groups), make sure those are exported from your 3D package and that you import them into UE4 when importing your content.

  • Max Vertex Count: For mobile devices, each mesh should have a maximum of 65,535 vertices. On other platforms, such as PC, you are limited by console and should test accordingly.

  • Collisions: All Skeletal Meshes should have a corresponding Physics Asset. These can be generated during import into UE4. See the Physics Asset Tool documentation for more information.

Help shape the future of Unreal Engine documentation! Tell us how we're doing so we can serve you better.
Take our survey
Dismiss