leileilol wrote on 2024-05-04, 00:59:

In the same year of pixel shading there'd been geometry tesselation which didn't gain steam beyond the cards of that year.

Ah, yes... that was interesting. If I remember correctly, there were screen shots of the tesselation on Radeon 8500 cards turning guns in popular (but not tesselation optimized) first person shooters into balloons. It was hilarious! I never got to see it in person though as I didn't own an 8500 (I went from a Geforce2 GTS to a Geforce4 Ti 4400).

After a little research\refresher: Yes, it was called ATi Truform, and the 8500\9100 were the only cards to have full hardware Truform support, though apparently later cards could do at least some kind of Truform with help from a fast CPU...

I can't find any of those hilarious old screenshots of the 8500's Truform being applied to the wrong models though. When implemented properly it certainly helped the terrible pointy player models of games from that time period, but I don't think many games actually bothered to use it, and I don't know what the performance hit was like.

Hardware tesselation eventually did become part of Direct3D years later though. Perhaps ATI was too early or MS didn't care enough yet.

I don't see how HW T&L could be seen as a gimmick when everything relies on it now, unless you specifically mean the fixed function variants of D3D7 cards, but even then, as I mentioned before unless a proper test with multiple games that actually use it is performed, we can't say for certain how effective it was or not.

The games don't specifically have to be D3D7. There are a number D3D8 games that have rendering paths for D3D7 cards and have a HW/SW T&L switch.

Even if the period CPUs could match or get close to it, one must keep in mind that not everyone had the latest CPUs. Many people didn't have the budget to upgrade both (which is the case even today) and when it came to games, GPUs usually took priority.

eddman wrote on 2024-05-04, 09:13:

I don't see how HW T&L could be seen as a gimmick when everything relies on it now, unless you specifically mean the fixed function variants of D3D7 cards

That's exactly what I said though, fixed function T&L was more useful for marketing than an actual feature, but evolved into a cornerstone piece of tech.

Truform is a great example to here as well. ATI/AMD kept chipping away at tesselation for a looooooong time before it became truly evolved from that n-patch implementation (of limited value) into where we are today. Hilariously enough, Nvidia absolutely stomped them performance wise* for several generations once it was mainlined into DirectX (* under extreme cases unlikely to be used without the intent of crippling Radeons but heavily tessellated flat planes are a completely different discussion for a completely different thread). I'm somewhat embarrassed to have overlooked this one since I had been working on a Sega Saturn emulator starting back around 2002 and toyed with truform as a (extremely) dirty hack to handle the whole "VDP1 only thinks of things as distorted sprites (aka forward textured quads) and nothing I can get my hands on can reliably accelerate them" deal. Obviously it didn't work but it turned out to be a really nice card once the drivers matured.

Somebody should do proper TnL benchmarks. Until then there is very little data to decide its usefulness.