and also, I think this still holds true
. Among the areas that were missing from the specifications were Hyper Z programming information, Truform, DX8 multisampling/FSAA support, vertex shader, ATI_fragment_shader, TV-Out, MPEG decoder, BIOS table layouts for the external TMDS transmitter, errata and chip bugs, and finally performance counters and debug information. Fortunately, however, thanks to reverse engineering of the fglrx driver, Stephane Marchesin (now known for his Nouveau work) and Roland Scheidegger had reverse engineered the Hyper Z programming information. Still lacking, however, is information on the hierarchical Z feature. Scheidegger had also reverse engineered the R200 vertex shader while David Airlie had lent him a hand in getting the ATI_fragment_shader to work.