Programmer Humor

My favorite story about docs is when I tried implementing multithreaded Raycast in Unity.

I needed it to hit multiple targets per ray. Should be pretty easy, after all - there is this parameter right in the constructor:

maxHits: The maximum number of Colliders the ray can hit.

And this is how you use it, straight from the docs:

The result for a command at index N in the command buffer will be stored at index N * maxHits in the results buffer.

If maxHits is larger than the actual number of results for the command the result buffer will contain some invalid results which did not hit anything. The first invalid result is identified by the collider being null. The second and later invalid results are not written to by the raycast command so their colliders are not guaranteed to be null. When iterating over the results the loop should stop when the first invalid result is found.

Well, no. It's not working like that. I was always getting just a single hit, but sometimes, I received two or more hits. After a few days of debugging, I have found a typo in bubblesort, which caused the multiple hits, and I was in fact getting only one hit every time.

Strange, must be a bug then. And then I found it. A bug report from 3 years ago. But it was closed as solved. And the resolution?

I have some news about the issue where RaycastCommand will only return a maximum of 1 hit regardless what you set maxHits to.

According to our developers, each individual raycast in a batch only does a Raycast single in PhysX which will only return the first hit, and not multiple hits if the ray passes through several objects which would require a different raycast function. The documentation simply doesn't explain this very well.

The docs above are from 2021. Three years after this. The fuck "doesn't simply explain it very well"? It literally explains it pretty damn well.

But looks like they've finally changed the docs for 2022+ at least, it did happen few years ago.