In Diablo 2, attack rate was calculated in terms of frames. This meant that there were discrete jumps as you broke certain Increase-Attack-Speed breakpoints. In Diablo 3, is there a similar discrete frame-based calculation, and what is the framerate used by the game engine in calculating attacks?
there might not be discrete frames (in terms of display), but the game logic could be in fixed-time-step intervals.– JimmyMay 18, 2012 at 16:49
Diablo III is not sprite-based like Diablo II was (Instead, it's full 3d), so there are no longer discrete frames.
The gameplay ramifications of this, of course, is that any amount of increased attack speed is equally viable. (Though not necessarily noticeable)
You can view your current attacks per second on your character sheet, and unlike in Diablo II (which listed only a speed, e.g. Slow / Fast / Very Fast), you'll actually get a decimal value.
How does this answer match up with something like this discussion about Barbarian Whirlwind breakpoints?– SternoApr 22, 2014 at 19:37
@Sterno It would imply that Diablo III reports all damage dealt / resource spent changes in a FixedUpdate loop running 60. Without being able to look into the Game's code, I can't tell you if the attacks are timestamped (such that all IAS is equally viable, with certain values of attack speed "registering" their damage some fractional seconds after the game engine considers them to have happened), or binned (such that there are IAS breakpoints for extremely specific values for extremely minor DPS increases). Since "Frames" is irrelevant for a game running on Blizzard servers (since the Apr 22, 2014 at 21:05
damage calculations have to happen on Blizz servers anyway), the "true" answer would be based on how fast the client and server can communicate, which would bin things anyway as they're passed to and fro back over the network. To test this, you would have to concoct a situation where the extra DPS from just shy of one of these "breakpoints" would prevent an enemy's attack (by killing them), and see if your character takes damage or not. I do not think that is feasibly testable. Apr 22, 2014 at 21:08
The other thing to recognize is that if there are IAS breakpoints, they are nowhere near the magnitude they were in Diablo II. I'd posit that they're not worth worrying about, one way or the other. Apr 22, 2014 at 21:20
This is an old question, but all the literature suggests that Diablo 3 has a 60 fps simulation rate, and that IAS should be tailored to hit an integral number of frames per attack at 60 fps.
I must admit I'm not an expert on d3 mechanics, so I'll accept the first non-link answer that describes how you go about listing out IAS breakpoints for a particular skill.– JimmyApr 24, 2018 at 16:10