switch root namespace name to NITLOAD

src/Nitload.Mathematics/Geometries/PlainGeometry/Define/ParticleOnPlain.cs

@@ -0,0 +1,58 @@
+// -----------------------------------------------------------------------------
+// file="ParticleOnPlain"
+// Project: StgSharp
+// Copyright (c) Nitload.
+// SPDX-License-Identifier: MIT
+// -----------------------------------------------------------------------------
+
+using Nitload.Mathematics;
+using Nitload.Mathematics.Numeric.Graphics;
+using Nitload.Mathematics.Numeric.Graphics;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Numerics;
+using System.Security.Cryptography.X509Certificates;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Nitload.Geometries
+{
+    public class ParticleOnPlain : IInstancing, IPlainEntity
+    {
+
+        public ParticleOnPlain(
+               PlainInstancingBuffer<ParticleOnPlain> buffer
+        )
+        {
+            if (buffer == null) {
+                throw new ArgumentNullException(paramName:nameof(buffer));
+            }
+            GlobalBuffer = buffer;
+            BufferId = buffer.CreateInstanceID();
+            ((IInstancingBuffer)buffer).InstanceList.Add(this);
+        }
+
+        public GeometryMotion Motion { get; set; }
+
+        public IInstancingBuffer GlobalBuffer { get; set; }
+
+        public int BufferId { get; set; }
+
+        Vec3 IInstancing.CenterPositionGlobal { get; set; }
+
+        bool IPlainEntity.CollideWith(
+                          IPlainEntity entity
+        )
+        {
+            throw new NotImplementedException();
+        }
+
+        Vec2 IPlainEntity.CenterPosition
+        {
+            get => GlobalBuffer.CoordAndRotationList[BufferId].XY;
+            set => throw new NotImplementedException();
+        }
+
+    }
+}