stgsharp/StgSharp.Common/Mathematics/Linear/Vec4.cs

//-----------------------------------------------------------------------
// -----------------------------------------------------------------------
// file="Vec4.cs"
// Project: StgSharp
// AuthorGroup: Nitload Space
// Copyright (c) Nitload Space. All rights reserved.
//     
// Permission is hereby granted, free of charge, to any person 
// obtaining a copy of this software and associated documentation 
// files (the “Software”), to deal in the Software without restriction, 
// including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, 
// and to permit persons to whom the Software is furnished to do so, 
// subject to the following conditions:
//     
// The above copyright notice and 
// this permission notice shall be included in all copies 
// or substantial portions of the Software.
//     
// THE SOFTWARE IS PROVIDED “AS IS”, 
// WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
// ARISING FROM, OUT OF OR IN CONNECTION WITH 
// THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//     
// -----------------------------------------------------------------------
// -----------------------------------------------------------------------
using StgSharp.HighPerformance;
using StgSharp.Internal.Intrinsic;
using StgSharp.Mathematics;

using System;
using System.Data.Common;
using System.Numerics;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

namespace StgSharp.Mathematics
{
    [StructLayout(LayoutKind.Explicit, Size = 16, Pack = 16)]
    public struct Vec4 : IEquatable<Vec4>, IFixedVector<Vec4>
    {

        [FieldOffset(0)] internal unsafe fixed float num[4];

        [FieldOffset(0)] internal M128 reg;

        [FieldOffset(0)] internal Vector4 vec;
        [FieldOffset(12)] public float W;

        [FieldOffset(0)] public float X;
        [FieldOffset(4)] public float Y;
        [FieldOffset(8)] public float Z;

        internal Vec4(Vector4 v)
        {
            Unsafe.SkipInit(out X);
            Unsafe.SkipInit(out Y);
            Unsafe.SkipInit(out Z);
            Unsafe.SkipInit(out W);
            Unsafe.SkipInit(out reg);

            vec = v;
        }

        internal Vec4(M128 v)
        {
            Unsafe.SkipInit(out X);
            Unsafe.SkipInit(out Y);
            Unsafe.SkipInit(out Z);
            Unsafe.SkipInit(out W);
            Unsafe.SkipInit(out vec);

            reg = v;
        }

        public Vec4(Vec3 v3, float w)
        {
            Unsafe.SkipInit(out X);
            Unsafe.SkipInit(out Y);
            Unsafe.SkipInit(out Z);
            Unsafe.SkipInit(out W);
            reg = v3.reg;
            W = w;
        }

        public Vec4(float x, float y, float z, float w)
        {
            vec = new Vector4(x, y, z, w);
        }

        public unsafe Vec2 XY
        {
            get => new Vec2(reg);
            set
            {
                X = value.X;
                Y = value.Y;
            }
        }

        public unsafe Vec3 XYZ
        {
            get => new Vec3(reg);
            set
            {
                float w = W;
                reg = value.reg;
                W = w;
            }
        }

        public static Vec4 One
        {
            get => new Vec4(1, 1, 1, 1);
        }

        public static Vec4 Zero
        {
            get => new Vec4(0, 0, 0, 0);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static Vec4 Add(Vec4 left, Vec4 right)
        {
            return left + right;
        }

        public override bool Equals(object obj)
        {
            return (obj is Vec4 v) ? (v == this) : false;
        }

        public override int GetHashCode()
        {
            return vec.GetHashCode();
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static Vec4 Subtract(Vec4 left, Vec4 right)
        {
            return left - right;
        }

        public override string ToString()
        {
            return vec.ToString();
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static Vec4 operator -(Vec4 left, Vec4 right)
        {
            return new Vec4(left.vec - right.vec);
        }

        public static bool operator !=(Vec4 left, Vec4 right)
        {
            return !(left == right);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static Vec4 operator *(Matrix44 mat, Vec4 vec)
        {
            mat.InternalTranspose();
            return new Vec4(
                Vector4.Dot(mat.transpose.colum0, vec.vec),
                Vector4.Dot(mat.transpose.colum1, vec.vec),
                Vector4.Dot(mat.transpose.colum2, vec.vec),
                Vector4.Dot(mat.transpose.colum3, vec.vec));
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static Vec4 operator +(Vec4 left, Vec4 right)
        {
            return new Vec4(left.vec + right.vec);
        }

        public static bool operator ==(Vec4 left, Vec4 right)
        {
            return left.vec == right.vec;
        }

        bool IEquatable<Vec4>.Equals(Vec4 other)
        {
            return vec == other.vec;
        }

    }
}