/// <summary>
/// Makes terrain visible and sets its appearance to its regular value, and ensures that it will
/// remain as such as long as it is visible.
/// </summary>
/// <param name="terrain">Terrain to modify.</param>
protected override void UpdateTerrainSeen(RogueLikeCell terrain)
{
// Invalid use of MemoryFieldOfViewHandlerBase
if (!(terrain is MemoryAwareRogueLikeCell awareTerrain))
{
throw new InvalidOperationException(
$"{nameof(MemoryFieldOfViewHandlerBase)} must only be used on a map that contains {nameof(MemoryAwareRogueLikeCell)} instances as its terrain.");
}
// If the appearances don't match currently, synchronize them
if (!awareTerrain.LastSeenAppearance.Matches(awareTerrain.TrueAppearance))
{
awareTerrain.LastSeenAppearance.CopyAppearanceFrom(awareTerrain.TrueAppearance);
awareTerrain.LastSeenAppearance.IsVisible = awareTerrain.TrueAppearance.IsVisible;
}
// Set up an event handler that will keep the actual appearance in sync with the
// true one, so long as the tile remains visible to the player. Because this could be
// called twice in certain state changes, we make sure we do not add the handler twice.
//
// Removing the event even if it does not exist does not throw exception and appears to be the
// most performant way to account for duplicates.
awareTerrain.TrueAppearance.IsDirtySet -= On_VisibleTileTrueAppearanceIsDirtySet;
awareTerrain.TrueAppearance.IsDirtySet += On_VisibleTileTrueAppearanceIsDirtySet;
}
/// <summary>
/// Makes terrain visible and sets its foreground color to its regular value.
/// </summary>
/// <param name="terrain">Terrain to modify.</param>
protected override void UpdateTerrainSeen(RogueLikeCell terrain)
{
terrain.Appearance.IsVisible = true;
if (terrain.Appearance.Decorators.Contains(ExploredDecorator))
{
// If there is only 1 decorator, it must be ours so we can replace
// the array with a static blank one
terrain.Appearance.Decorators = terrain.Appearance.Decorators.Length == 1 ? Array.Empty <CellDecorator>() : terrain.Appearance.Decorators.Where(i => i != ExploredDecorator).ToArray();
}
}
/// <summary>
/// Makes terrain invisible if it is not explored. Makes terrain visible but tints it using
/// <see cref="ExploredDecorator"/> if it is explored.
/// </summary>
/// <param name="terrain">Terrain to modify.</param>
protected override void UpdateTerrainUnseen(RogueLikeCell terrain)
{
// Parent can't be null because of invariants enforced by structure for when
// this function is called
var parent = Parent !;
// If the unseen terrain is outside of FOV, apply the decorator to tint the square appropriately.
if (parent.PlayerExplored[terrain.Position])
{
terrain.Appearance.Decorators = terrain.Appearance.Decorators.Append(ExploredDecorator).ToArray();
}
else // If the unseen tile isn't explored, it's invisible
{
terrain.Appearance.IsVisible = false;
}
}
/// <summary>
/// Makes terrain invisible if it is not explored. Changes the appearance by calling
/// <see cref="ApplyMemoryAppearance"/> if it is explored. The terrain will continue to
/// appear as set by that function (even if its true appearance changes) until the player
/// sees it again.
/// </summary>
/// <param name="terrain">Terrain to modify.</param>
protected override void UpdateTerrainUnseen(RogueLikeCell terrain)
{
// Invalid use of MemoryFieldOfViewHandlerBase
if (!(terrain is MemoryAwareRogueLikeCell awareTerrain))
{
throw new InvalidOperationException(
$"{nameof(MemoryFieldOfViewHandlerBase)} must only be used on a map that contains {nameof(MemoryAwareRogueLikeCell)} instances as its terrain.");
}
// If the event handler for synchronizing the appearance with true appearance is added, remove it
// which will cause the appearance to remain as last-seen if it changes
awareTerrain.TrueAppearance.IsDirtySet -= On_VisibleTileTrueAppearanceIsDirtySet;
// If the unseen terrain is explored (eg. it was in FOV previously), apply the visual change
// as appropriate
if (Parent !.PlayerExplored[terrain.Position])
{
ApplyMemoryAppearance(awareTerrain);
}
