Compatibility of 3Dc / LATC?

[JoshKlint]

How well supported is 3Dc / LATC compression on the following hardware?:
-OpenGL ES devices (iOS, Android)
-OpenGL 2.1 compliant drivers (ATI, NVidia)
-Intel integrated graphics chips

[Dark Photon]

3Dc - ATI x800 GPU and later (I think). No NVidia AFAIK.

LATC / RGTC - NVidia GeForce 8+ and later. Don't know for sure about ATI here. But since RGTC has been part of the base OpenGL spec since OpenGL 3.0, it's probably been supported for quite a while on ATI. These require GL3+ hardware, though you can access them on this hardware via a GL2.x context through extensions.

[Alfonse Reinheart]

I did some checking, and 3Dc is, in terms of format, no different from LATC, which itself is functionally no different from RGTC.

[arekkusu]

RGTC is a superset; it supports signed formats, 3Dc does not.

[Alfonse Reinheart]

RGTC is a superset; it supports signed formats, 3Dc does not.

That's just an interpretation of the data; the actual stored data, the bits that make up a block, is the same whether it's signed or not.