UE4 Texture Guidelines for Mobile Platforms

Texture Guidelines for Mobile Platforms

Mobile Game Development

On this page:

Overview
Texture Usage in Materials
Per-Device Texture LOD

Overview

Since mobile platforms use OpenGL ES2, there are restrictions imposed on textures. Some of the restrictions come into play when creating textures:

A maximum size of 2048 in either dimension. This is the largest size allowed by the PVR compressor.

Dimensions must both be a power of 2 (i.e. 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, or 2048).

You should use square textures whenever possible as they make more efficient use of memory.

In addition, texture settings need to be set up properly to work on mobile platforms:

It is recommended that you only use TC_Default or TC_NormalMap in the Compression Settings as any other setting could cause your Texture to take up more memory than expected on your target device.

The sRGB property should be enabled.

Texture Usage in Materials

Most opaque Materials should only need BaseColor, Roughness, and Normal to come from textures. Specular should not be specified and Metallic can be a constant. Given that base set of Material properties, most Materials that only have one layer should use the
following setup which only requires two textures:

Texture 1

BaseColor in RGB

Roughness in alpha

TC_Default compression

Texture 2

Normal map in RGB

TC_NormalMap compression

Additional layers will need to use more textures, with the option of only layering in BaseColor + Roughness to avoid multiple normal map texture fetches.

Per-Device Texture LOD

With the release of Unreal Engine 4.8 you can now specify Texture LOD settings on a per-device basis as opposed to per-platform. To set the Texture LOD settings per-device you will need to do the following.

From the main Tool Bar open the Devices Profiles manager by going to Windows > Developer Tools and then clicking on Device Profiles.



After clicking on the Device Profiles option the following menu will be displayed.



From this menu select the device you want to edit and then click on the three dots that are to the left of the device name to open that devices profile.

To make a change just click on the property you want to adjust and then input what you want the setting to be.