3Dlabs p10 opengl2 and image processing

if you read the review of p10 VPU you may have noticed an advanced programmable image processing (wavelet…)
how could we programm this using opengl2 api? seems that openGl2 lacks a little bit of programmabily in this area…

And another thing from the article - “…For example, nothing prevents a processor in the shader section from writing out data to memory that can then be accessed by one of the scalar vertex processors, though it’s hard to think of any reason to do it.”
That looks like a nice way to do displacement mapping and procedural geometry.