Re: Check if all 256 bits are clear or set ?

I found it fun to scan the internet to see if there is anybody that has/needs these same methods. 

I came across unity documentation:

https://docs.unity3d.com/Packages/[email protected]/api/UnityEngine.Rendering.BitArray256.html

Describing

allTrue

True if all bits are 1.
Declaration

public bool allTrue { get; }

and it took a while to find the exact source code but it's here:

https://github.com/needle-mirror/com.unity.render-pipelines.core/blob/master/Runtime/Utilities/BitArray.cs

  public bool allTrue => data1 == ulong.MaxValue && data2 == ulong.MaxValue && data3 == ulong.MaxValue && data4 == ulong.MaxValue;

from this class to give it a bit more context:
    /// <summary>
    /// Bit array of size 256.
    /// </summary>
    [Serializable]
    [System.Diagnostics.DebuggerDisplay("{this.GetType().Name} {humanizedData}")]
    public struct BitArray256 : IBitArray
    {
        [SerializeField]
        ulong data1;
        [SerializeField]
        ulong data2;
        [SerializeField]
        ulong data3;
        [SerializeField]
        ulong data4;

        /// <summary>Number of elements in the bit array.</summary>
        public uint capacity => 256u;
        /// <summary>True if all bits are 0.</summary>
        public bool allFalse => data1 == 0uL && data2 == 0uL && data3 == 0uL && data4 == 0uL;
        /// <summary>True if all bits are 1.</summary>
        public bool allTrue => data1 == ulong.MaxValue && data2 == ulong.MaxValue && data3 == ulong.MaxValue && data4 == ulong.MaxValue;
        /// <summary>Returns the bit array in a human readable form.</summary>

So let's go back to this code:

  public bool allTrue => data1 == ulong.MaxValue && data2 == ulong.MaxValue && data3 == ulong.MaxValue && data4 == ulong.MaxValue;

It's a bit funny to see both solutions for allFalse and AllTrue the naming is nice, in my case you could think of it as AllEmpty and AllFull hint hint about secret code lol.

Anyway

At least the allFalse code could be written a bit more efficient HAHA ! =D
as already explored.

But can the allTrue code be written more efficient as well ? I think so...

At least the and's could be done on the data itself

(data1 && data2 && data3 && data4) == ulong.MaxValue
3's and's
1 comparison to max value.

Bye for now,
  Skybuck.