It feels like graphics drivers do / did this a lot too. At the very least they make specific optimizations for specific games, probably by tweaking settings and features that the game developers didn't optimize properly themselves.

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kalleboo 4 hours ago | parent | next [-]

Famously if you renamed Quake 3 to "Quack" 3, it would slow down on the ATI Radeon 8500 https://web.archive.org/web/20091016055550/https://hardocp.c...

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account42 3 hours ago | parent [-]

That's a case of the driver cheating but there are also lots of cases where the game is just full of bugs that the driver has to work around in order to not be blamed for them.

	▲	Gibbon1 3 hours ago \| parent [-]
		I've said over the years a few times, this isn't our fault but it's our problem.

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SyzygyRhythm 4 hours ago | parent | prev [-]

There are many, many, cases like this, including correctness fixes. One recent example I remember had a shader that computed: x = a / b * b

The optimizer was allowed, but not obligated, to transform that into: x = a

However, in this case, b was sometimes 0. And if so, the unoptimized version computed: x = a / 0 * 0 = Inf * 0 = NaN

So badness ensued if the that particular path didn't get optimized, which could happen under various circumstances. We had to add some code to ensure that transformation always happened on that game.

	▲	DarkUranium an hour ago \| parent [-]
		I'm curious, what's the ratio of: - deciding to inform the game developer & wait for reply vs not waiting for reply vs just fixing it yourself without informing the developer; and - if informed: developer actually fixing it vs only saying they would fix it vs no reply whatsoever (not counting automated "thank you for your inquiry" replies, in cases where you don't already have more direct channels to the dev than email) I've always kind of wondered this because in a way, it's kind of weird that it's fixed for them, at least for new releases / games actively being developed. (Full disclosure: I'm a game developer myself, with a very high interest in engine plumbing & dev [including graphics], though finding a job for the latter is easier said than done.)