Possible to do dependent reads with combiners?

The red book, version 2.0, bottom of page 655, seems to imply that it’s possible to do dependent texture reads with texture combiners. The paragraph is a bit ambiguous, though.

As far as I was aware, this isn’t possible; am I wrong?


I believe you’re right.
As far as I can remember the only way to do dependant lookups is to use NV_texture_shader[2,3] (and they are somewhat limited anyway) or jump directly into fragment programming.

Nice one, much obliged… :wink:


nv_texture_shader is nearly the same as d3d’s pixel shader 1.1

Nothing in vanilla combiners uses dependent reads. ARB combiner & crossbar specifications don’t actually say anything about setting texture cooridnates of another unit.

Many thanks folks, that’ll be a “no”, then :slight_smile: