I'm not sure if dev is reading, but:
+ cute girl
+ nice outfits
+ great visuals and audio
+ damn good animations
- optimization - I know it's 2024, but it shouldn't burn not so old hardware on minimal settings
- buggy physics - it seems it is based on frame, you should always have it on constant tick, now hair is behaving completely different on different framerates
Thank you!
A bit of an explanation for physics simulation: While nothing in the game is directly frame dependent, physics have different rules generally, so it might seem this way when there is simulation slowdown.
The Physics in the game do run at a different but fixed frame rate compared to the graphics. This frame rate is usually at 50 ticks/second. Deviations are calculated using the time between updates, just as you would for other animations. Like, when an object travels at 1 unit / second, you can calculate how far the object has traveled even if an update took 10 seconds.
Now, for a lot of physics simulation in general, and the hair in particular, simulation is unfortunately not easily predictable, because there is collision, restrictions, and physics interconnectivity. This means that you can't easily tell where the simulation will be without actually simulating it. So if the update rate can't be kept at 50/second becuase of slowdown (due to rendering or cpu), you have to subdivide the time step and and do multiple updates at once to compensate. For example, the object traveling at 1 unit/second might have passed through a wall when there is only one update in 10 seconds, which we don't want. All this is of course rather counter-productive to what usually caused longer updates.
Basically, if you took to long to update from lack of cpu/gpu power, you have to do even more work to catch up without losing accuracy. In the case of the hair, rather than causing a fps dip and even possibly a freeze to calculate even more to catch up, simulation updates have to be somewhat predicted with a lot less accuracy, which causes the hair is going wild. Unfortunately, the more complex a simulation is, the worse the effect ends up being.
And in this case it's not the hair simulation necessarily causing the slowdown, but it will be affected if there is any (like when frames take too long to render, specifically in framerates below 50fps, because then it becomes hard to compensate and keep a fluid simulation in real time)
When the game runs at higher framerates, the simulation will be deterministic no matter how high the frame rate is. (there can still be some animation jitter, but that has other causes)
For optimization in general. The hair is responsible for 30-50% of slowdown depending on hardware. It's rather new technology in general and very performance intensive, which is why you usually don't see it being used in games just yet. Since d.sim is focused on the character most and foremost I decided to use it for the visual quality it provided.
However, in the next version, I will provide a card-hair fallback, which is the technique used in most games. This will significantly boost fps on older hardware (I predict up to 50% more fps, or more even, though hard to say).