/// <summary> Constructor. </summary>
/// <param name="position"> The position of the given chunk. </param>
public Chunk(ChunkCoordinate position)
{
Position = position;
_items = new GridItem[NumberOfGridItemsWide * NumberOfGridItemsHigh];
// TODO do this elsewhere
for (int y = 0; y < NumberOfGridItemsHigh; y++)
{
for (int x = 0; x < NumberOfGridItemsWide; x++)
{
var gridPosition = new GridCoordinate(position, new InnerChunkGridCoordinate(x, y));
var gridItem = GetGridItemAt(gridPosition);
this[gridPosition.InnerChunkGridCoordinate] = gridItem;
}
}
}
/// <summary> Loads the chunk from the world for the given coordinate, if it needs to be updated. </summary>
/// <param name="chunkCoordinate"> The coordinate of the chunk to load, if it is different. </param>
private void UpdateChunkAt(ChunkCoordinate chunkCoordinate)
{
Chunk newChunk;
if (chunkCoordinate.X < 0 || chunkCoordinate.Y < 0)
{
newChunk = null;
}
else if (chunkCoordinate.X >= WorldGrid.NumberOfChunksWide ||
chunkCoordinate.Y >= WorldGrid.NumberOfChunksHigh)
{
newChunk = null;
}
else
{
newChunk = _world[chunkCoordinate];
}
var viewableXOffset = MathUtils.PositiveRemainder(chunkCoordinate.X, NumberOfChunksWide);
var viewableYOffset = MathUtils.PositiveRemainder(chunkCoordinate.Y, NumberOfChunksHigh);
var oldChunk = VisibleChunks[viewableXOffset, viewableYOffset];
// they're the same so we don't have to do anything
if (oldChunk == newChunk)
{
return;
}
VisibleChunks[viewableXOffset, viewableYOffset] = newChunk;
// we've detected a change, so unsubscribe + subscribe from all of the stuff
if (oldChunk != null)
{
oldChunk.GridItemChanged -= OnGridItemChanged;
}
if (newChunk != null)
{
newChunk.GridItemChanged += OnGridItemChanged;
}
OnViewableChunkChanged(oldChunk, newChunk);
}
public GridCoordinate(ChunkCoordinate chunkCoordinate, InnerChunkGridCoordinate innerCoordinate)
{
X = (chunkCoordinate.X << Chunk.XGridCoordinateToChunkCoordinateBitShift) + innerCoordinate.X;
Y = (chunkCoordinate.Y << Chunk.YGridCoordinateToChunkCoordinateBitShift) + innerCoordinate.Y;
}
/// <summary>
/// Returns true if the given coordinate is a valid coordinate that can be used in this grid.
/// </summary>
public bool IsValid(ChunkCoordinate chunkCoordinate)
{
return(chunkCoordinate.X >= 0 && chunkCoordinate.X < NumberOfChunksWide &&
chunkCoordinate.Y >= 0 && chunkCoordinate.Y < NumberOfChunksWide);
}
/// <summary>
/// Gets the chunk at the specified coordinate.
/// </summary>
public Chunk this[ChunkCoordinate coordinate]
{
get { return(_chunks[CalculateIndex(coordinate.X, coordinate.Y)]); }
set { _chunks[CalculateIndex(coordinate.X, coordinate.Y)] = value; }
}
