add docfx samples.

Disp/DemoPickable.cs

@@ -0,0 +1,47 @@
+using Hi.Disp;
+using Hi.Geom;
+using System;
+
+namespace Sample.Disp
+{
+    /// <remarks>
+    /// ### Source Code
+    /// [!code-csharp[SampleCode](~/../Hi.Sample.Wpf/Disp/DemoPickable.cs)]
+    /// </remarks>
+    public class DemoPickable : IDisplayee
+	{
+		private readonly Drawing draw;
+		private readonly ShowEventPickable pickable;
+
+		public DemoPickable()
+		{
+			pickable = new ShowEventPickable();
+			double pid = pickable.PickingID;
+			double[] vs = new double[] {
+				//pickID, x,y,z
+				pid, 0,0.1,0.1,
+				pid, 0.1,0,0,
+				pid, 0.1,0,0.1
+			};
+			draw = new Drawing(vs, Stamp.PV, GL.GL_TRIANGLES);
+		}
+        /// <inheritdoc/>
+        public void Display(Bind bind)
+		{
+			draw.Display(bind);
+		}
+        /// <inheritdoc/>
+        public void ExpandToBox3d(Box3d dst)
+		{
+			draw.ExpandToBox3d(dst);
+		}
+
+		[STAThread]
+		public static void Main()
+		{
+            DemoUtil.RunApplication("DemoPickable", new DemoPickable());
+		}
+	}
+
+
+}