ASTC texture format with/without alpha consumes same amount of memory?

[Peter77]

Using the ASTC texture format for a texture with and without an alpha channel, consumes the same amount of memory? Is this correct? I’ve tested Unity 2018.4.31f1 and Unity 2019.4.20f1.

Without alpha channel: 170 KB:

With alpha channel: 170 KB

[Sky77]

Yep it is correct.

[AcidArrow]

Is Astc Rgb Encode Gone?

The ASTC format itself does not have a variant without alpha channel. If your source texture has alpha but you don’t don’t need it then just set “Alpha Source” to “None”. This should give you the same behavior and quality as previous Unity versions. The ASTC RGB TextureImporterFormat was added to Unity basically as a workaround when there was no “Alpha Source” menu.