We are creating a game targeted at Ouya (Tegra3) and have a large number of alpha-masked textures. I would like to import these textures as DXT1 with 1-bit alpha, but it seems the DXT importer in the engine ignores alpha on DXT1 textures. DXT5 is twice the size/cost and we don’t need the extra alpha precision for the vast majority of our textures. I tried using an external converter to create .dds texture files already converted to DXT1, but it seems the engine still somehow removes the alpha bit.
Am I doing something wrong, or does Unity really not support DXT1 alpha?
DXT 1 does not support alpha. you have to drop one of the color channels to store any form of alpha
Use DXT3 instead
This is what I’m talking about:
http://www.opengl.org/wiki/S3_Texture_Compression#DXT1_with_1-bit_Alpha
It was my understanding that pretty much all hardware that supports DXT1, supports the ubiquitous 1-bit alpha extension GL_COMPRESSED_RGBA_S3TC_DXT1_EXT
Unity doesn’t seem to support DXT1 w/ 1 bit alpha. Is there planned support for this in the future? Is there another option for transparent texture compression that only needs 1 bit alpha?