
ASTC
stands for Adaptive Scalable Texture Compression
, which is a popular texture compression scheme on mobile platforms. When the platform uses ASTC packaging, UE defaults to using the Intel ISPC Texture Compressor for texture compression. However, it has some limitations, only supporting compression specifications of 8x8
and above, while 10x10
and 12x12
are not supported. If specified in the project, it will still use the 8x8
specification. In addition to ISPC, the engine also provides ARM’s astc-encoder compression method, which supports specifications below 8x8
, but is not enabled by default. Moreover, the integrated compression efficiency in the engine is very low, and using astc-encoder to compress textures can pose a significant challenge to Cook time in large-scale resources.
This article analyzes the settings for using ASTC compression for textures in UE, as well as the compression efficiency and optimization ideas for the astc-encoder in the engine.