i never played hla. but this looks like a lowres dynamic cubemap capture. there’s no way this is a parallax corrected static cubemap. for realtime capture you don’t need parallax correction.
either way… straying away from the refraction part of the question.
and… my thinking is… it’s hard. you could maybe have distance field refraction. the problem is you have to trace and refract thru the translucent or as somebody suggested an opaque object’s distance field and hit something that is essentialy occluded making this very hard. and you’d still not get multibounce, i guess.
an the other end… iirc… i got some multibounce raytraced refraction semi working in a wip daily build back mid last year. it was wip tho. not complete.