/// <summary>
/// Creates the UV mapping of a block.
/// </summary>
/// <param name="b">The block to get the mapping of.</param>
/// <param name="d">The direction of the block to render.</param>
/// <returns>UVMap representing the UV mapping of the current block.</returns>
internal static UVMap?CreateUVMapping(this BlockID b, Direction d)
{
/*
* Cheat Sheet
* x * 2^y = x << y
* x / 2^y = x >> y - Except that / rounds up for negatives, and >> always rounds down
* x % 2^y = x & (2^y - 1)
*/
// Same as X % 256
// 256 = (2^16) = 1 << 16
// x % 256 = x & (256 - 1)
// x % 256 = x & ((1 << 16) - 1)
Vector2?posOrNull = b.TileVector(d);
if (posOrNull == null)
{
return(null);
}
Vector2 tile = posOrNull.GetValueOrDefault();
float x = ((int)tile.Y & ((1 << 16) - 1)) * Settings.Offset; // U
float y = ((int)tile.X & ((1 << 16) - 1)) * Settings.Offset;
return(new UVMap(
new Vector2(x + Settings.Offset, y),
new Vector2(x, y),
new Vector2(x + Settings.Offset, y + Settings.Offset),
new Vector2(x, y + Settings.Offset)
));
}
