add overload for defining BufferUsageHint

Pilz.Drawing.Drawing3D.OpenGLRenderer/Rendering/Renderer.vb

@@ -141,6 +141,14 @@ Namespace RenderingN
         ''' Creates the Buffers and store the requied Data.
         ''' </summary>
         Public Sub RenderModel()
+            RenderModel(BufferUsageHint.StaticDraw)
+        End Sub
+
+        ''' <summary>
+        ''' Creates the Buffers and store the requied Data.
+        ''' </summary>
+        ''' <param name="bufferUsage">The hint how the graphics card should handle the data.</param>
+        Public Sub RenderModel(bufferUsage As BufferUsageHint)
             ReleaseBuffers()
 
             For Each mesh As Mesh In obj3d.Meshes