The previous lazy rendering means the snapshot of the render state might be more up to date then when the frozen actor actually did become visible. Now, we take this snapshot as soon as needed. We still retain the performance of only doing this rendering when needed by avoiding extra rendering until the visibility cycles again.
In places where arrays were being treated as a set, just create a set directly. This reveals the intention of such collections better, and also improves performance by allowing set based methods to be used.
Previously actors that could be frozen under fog but were currently visible would be rendered by the frozen under fog system constantly in order to keep a copy of the renderables ready to go for the frozen counterpart when the actor became invisible. Instead, we now delay this extra rendering until the actor actually becomes invisible. This eliminates the wasted rendering to generate renderables that were never used.
The FrozenUnderFog.Tick method will now reuse the calculation do by the frozen actor when it had to calculate its visibility, this prevents it having to re-do the fairly expensive visibility calculation.
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.
- Only update shroud within the visible screen area, rather than the whole map. This improves performance on larger maps significantly when scrolling around since large portions of the shroud do not need to be updated.
- Provide methods in Shroud to return delegates to check for explored/visibility for tiles within a certain region. This allows it to return more efficient delegates whenever the region is within the map bounds, or shroud/fog is disabled. In the typical case where the region is in bounds and shroud/fog is enabled, the fast check is almost twice as fast as the slow check.
- Use the Shroud delegate functions in shroud rendering, frozen actors, minimap rendering and resource layer areas to provide a speedup since these areas of code can often take advantage of the fact they perform checks within the map boundary.
- Cache current element in CellRegionEnumerator to prevent repeated work if the element is accessed more than once.
- Decrease the size of elements in some arrays in hopes of reducing memory needs and improving cache hits.
- Extract an enum for edges rather than using magic numbers for everything.
- Remove duplicated code between FoggedEdges and ShroudedEdges by hosting the visibility function into a delegate.
- Make minimap methods more readable.
- Tidy formatting.
- Make some fields readonly.
- Remove unused usings.
Targeted some methods that generated allocated a lot of memory in the main game loop:
- Actor.Render - Changed LINQ calls into equivalent loops. No allocation for delegates.
- Animation.Render - Returned an array rather than a yield expression. The array uses less memory than the complier generated enumerable.
- FrozenActor and FrozenUnderFog - Materialize the footprint into an array: The enumerable is not-trivial to evaluate is and evaluated many times inside the Tick function. The memory needed is minimal. Changed LINQ into equivalent loops to prevent delegate allocation. Should result in overall much faster calls.
- Widget.GetEventBounds - Changed LINQ calls into equivalent loops.
- MobileInfo.CanEnterCell - Changed LINQ calls into equivalent loops. Don't materialize list of blocking actors every time, instead enumerate them and only when they need to be checked.
- FrozenUnderFog.TickRender - Generate the renderables lazily and also remove a no-op Select call.
