public Mesh?Generate(ChunkPos chunkPos)
{
var storages = new ChunkPaletteStorage <Block> [3, 3, 3];
foreach (var(x, y, z) in Neighbors.ALL.Prepend(Neighbor.None))
{
if (_chunkStore.TryGetEntityID(chunkPos.Add(x, y, z), out var neighborID))
{
if (_storageStore.TryGet(neighborID, out var storage))
{
storages[x + 1, y + 1, z + 1] = storage;
}
}
}
var centerStorage = storages[1, 1, 1];
var indexCount = 0;
var vertexCount = 0;
for (var x = 0; x < 16; x++)
{
for (var y = 0; y < 16; y++)
{
for (var z = 0; z < 16; z++)
{
var block = centerStorage[x, y, z];
if (block.Prototype.IsNone)
{
continue;
}
var blockVertex = new Vector3(x, y, z);
var textureCell = _textureCellStore.Get(block.Prototype.ID);
foreach (var facing in BlockFacings.ALL)
{
if (!IsNeighborEmpty(storages, x, y, z, facing))
{
continue;
}
if (_indices.Length <= indexCount + 6)
{
Array.Resize(ref _indices, _indices.Length << 1);
}
if (_vertices.Length <= vertexCount + 4)
{
Array.Resize(ref _vertices, _vertices.Length << 1);
Array.Resize(ref _normals, _vertices.Length << 1);
Array.Resize(ref _uvs, _vertices.Length << 1);
}
for (var i = 0; i < TRIANGLE_INDICES.Length; i++)
{
_indices[indexCount++] = (ushort)(vertexCount + TRIANGLE_INDICES[i]);
}
var normal = facing.ToVector3();
for (var i = 0; i < 4; i++)
{
var offset = OFFSET_PER_FACING[(int)facing][i];
_vertices[vertexCount] = blockVertex + offset;
_normals[vertexCount] = normal;
_uvs[vertexCount] = i switch {
0 => textureCell.TopLeft,
1 => textureCell.BottomLeft,
2 => textureCell.BottomRight,
3 => textureCell.TopRight,
_ => throw new InvalidOperationException()
};
vertexCount++;
}
}
}
}
}
return((indexCount > 0)
? _meshManager.Create(
_indices.AsSpan(0, indexCount), _vertices.AsSpan(0, vertexCount),
_normals.AsSpan(0, vertexCount), _uvs.AsSpan(0, vertexCount))
: (Mesh?)null);
}