PPos is best thought of as a cell grid applied in
screen space. Multiple cells with different
terrain heights may be projected to the same PPos,
or to multiple PPos if they do not align with the
screen grid.
PPos coordinates are used primarily for map edge
checks and shroud / visibility queries.
VisibilityType.Footprint reveals from each footprint cell.
VisibilityType.CenterPosition reveals from the
actor’s CenterPosition only (as the original
games did).
The per-actor visibility now tracks all cells
inside the map area (including those outside the
currently visible bounds), but the shroud/fog is
only cleared if the cell is inside the currently
visible bounds.
Reduce code duplication by extracting a common class to deal with spatial partitioning of actors, and use some (cached) delegates to reduce duplication further without affecting performance too much.
Speed up updates and removal of actors by caching their location so we only need to update or remove them from bins they are actually in (typically very few), compared to having to check every bin for removals which is much more work in comparison.
Speed up checking for actors inside a region by checking if items are located entirely within the bin they are located in. If so, we don't need to add them to the hash-set for de-duplication purposes which is fairly expensive.
Remove unnecessary delegate.
Use extension method syntax.
Fix HealthInfo.NotifyAppliedDamage’s desc.
Remove unused using directives.
Remove explicit type declaration in Manifest.
By maintaining a set of changed cells we can avoid repeating work for cells that change multiple times before being rendered. The shroud renderer and radar widget now delay their work until they must render, and thus process each changed cell only once. This avoids significant repetition that was causing major slowdown when many actors were in the world.
A unit with the CreatesShroud or RevealsShroud trait must update all shrouds when it changes position. Calculating the tiles it can currently see is an expensive calculation that previously had to be repeated for every shroud that needed to know these tiles.
Now, we lazily populate a ref parameter to allow it to be reused for an actor if possible. The biggest improvement comes from the fact that allied players can re-use this calculation when updating their shrouds. Since many games includes a neutral player allied to both sides, most games will see a decent speedup.
To resolve the ambiguity introduced when the introduction of isometric maps meant that cell and map coordinates were no longer equivalent, a new type has been introduced so they can each be represented separately.
