Catalyzes the NAD(P)H-dependent reduction of dihydroxyacetonephosphate (DHAP or glycerone phosphate) to glycerol 1-phosphate (G1P). The G1P thus generated is used as the glycerophosphate backbone of phospholipids in the cellular membranes of Archaea. Is also able to catalyze the reverse reaction, i.e. the NAD(P)(+)-dependent oxidation of G1P but not of G3P. Is not active toward glycerol, dihydroxyacetone, glyceraldehyde-3-phosphate, glyceraldehyde and glycerol-2-phosphate. NAD(+) + sn-glycerol 1-phosphate = dihydroxyacetone phosphate + H(+) + NADH NADP(+) + sn-glycerol 1-phosphate = dihydroxyacetone phosphate + H(+) + NADPH Binds 1 zinc ion per subunit. Partially inhibited by divalent metal cations such as Co(2+), Cu(2+) and Ni(2+). Optimum pH is 6.6-7-4. Activity decreases gradually at pH over 7.4 or below 6.6. Optimum temperature is 75 degrees Celsius. Membrane lipid metabolism; glycerophospholipid metabolism. Homooctamer. G1PDH is a pro-R type dehydrogenase, which selectively transfers the pro-R hydrogen from NADH to dihydroxyacetonephosphate. Belongs to the glycerol-1-phosphate dehydrogenase family.