Two different issues were causing a path search to not explore cells in order of the cheapest estimated route first. This meant the search could sometimes miss a cheaper route and return a suboptimal path.
- PriorityQueue had a bug which would cause it to not check some elements when restoring the heap property of its internal data structure. Failing to do this would invalidate the heap property, meaning it would not longer return the items in correct priority order. Additional tests ensure this is covered.
- When a path search encountered the same cell again with a lower cost, it would not update the priority queue with the new cost. This meant the cell was not explored early enough as it was in the queue with its original, higher cost. Exploring other paths might close off surrounding cells, preventing the cell with the lower cost from progressing. Instead we now add a duplicate with the lower cost to ensure it gets explored at the right time. We remove the duplicate with the higher cost in CanExpand by checking for already Closed cells.
The types for Int32 and Boolean are currently replaced with friendly names of int and bool for the docs. Ensure we apply the same handling when these are nullable types, changing the output from Int32? and Boolean? to int? and bool?
Requires<T> means that trait of type T will be initialized first, and asserts that at least one exists. The new NotBefore<T> means that trait of type T will be initialized first, but allows no traits.
This allows traits to control initialization order for optional dependencies. They want to be initialized second so they can rely on the dependencies having been initialized. But if the dependencies are optional then to not throw if none are present.
We apply this to Locomotor which was previously using AddFrameEndTask to work around trait order initialization. This improves the user experience as the initialization is applied whilst the loading screen is still visible, rather than the game starting and creating jank by performing initialization on the first tick.
This helps improve the safety of code the uses reflection when methods may get renamed, and helps navigating code as the nameof will show up when searching for references to members.
