basis_universal is a universal texture format that decodes to your specific compressed format at runtime. It is ideal for use in multi-platform (especially mobile) environments, where you need to maintain minimal size and be able to transcode to different hardware supported formats at runtime.
The asset type name is "texture_basisu" with rizz_texture_load_params (same as textures) as load parameters for asset loader.
With the exception of fmt field, which is mandatory when loading basis files, because basis files needs to transcode to a valid
format at runtime and you need to provide it explicitly, here's an example usage:
rizz_asset img = the_asset->load("texture_basisu", "/path/to/image.basis",
&(rizz_texture_load_params){ .fmt = IS_MOBILE ? SG_PIXELFORMAT_ETC2_RGB8 : SG_PIXELFORMAT_BC1_RGBA },
0, NULL, 0);
You can look into 02-quad example for actual usage of this format and plugin.