What does the fixed timestep mean in Unity?

What does the fixed timestep mean in Unity?

In Unity, this means that there are two main update passes: FixedUpdate and Update. The FixedUpdate pass steps forward in increments of 0.02 game-time seconds The default is 0.02 seconds. You can change the fixed timestep amount by setting Time.fixedDeltaTime — even at runtime! , regardless of rendering or any other performance factors.

Why does fixed timestep setting affect game speed?

You don’t need that with physics, because physics are in fixedupdate, and run at a fixed rate and hence don’t need deltatiming. On your rigid bodies, you enable interpolation which will smooth them out. Great – thanks for clearing that up for me.

Why does unity update at 60Hz every frame?

Unity seems to be trying to run the slower FixedUpdate in lockstep with the faster Update until it must pause to maintain 50FPS. On the other hand, Update is perfectly smooth. We can thank V-Sync for this. My display is set to 60Hz, and as such, Unity performs an Update whenever the display is ready for the next frame.

What’s the difference between fixedupdate and update in Unity?

Depending on the circumstances, multiple FixedUpdates may run between two Updates (the game is render-blocked), or multiple Updates may run between two FixedUpdates (rendering is faster than the FixedUpdate step). By default on desktop, Unity runs the FixedUpdate at 50 FPS and the Update at 60 FPS (the VSync rate).

Is there a way to change the fixed timestep?

You can change the fixed timestep amount by setting Time.fixedDeltaTime — even at runtime!, regardless of rendering or any other performance factors. The key here is that FixedUpdate is reliable.

Why do I need to do fixed DT time steps?

Advance the physics simulation ahead in fixed dt time steps while also making sure that it keeps up with the timer values coming from the renderer so that the simulation advances at the correct rate. For example, if the display framerate is 50fps and the simulation runs at 100fps then we need to take two physics steps every display update. Easy.