// draw text
        InputHandler input;
        bool drawFPS = false;
        SpriteFont font;

       public FpsCounter(Game game)
            : base(game)
        {
            Enabled = true;
            this.game = game;
            input = (InputHandler)game.Services.GetService(typeof(InputHandler));
        }

        public override void Update(GameTime gameTime)
        {
            base.Update(gameTime);
            if (input.IsKeyPressed(Keys.F))
                drawFPS = !drawFPS;

// 중간생략..
        }

        public sealed override void Draw(GameTime gameTime)
        {
            Game.Window.Title = “FPS: ” + fps.ToString();
            if (drawFPS)
            {
                // draw the text for fpsCounter
                spriteBatch.Begin();
                spriteBatch.DrawString(font, fps.ToString(), Vector2.One, Color.White);
                spriteBatch.End();
            }
        }

void InitializePrimitive()
{
// 중간생략…
            // Initialize our Vertex Declaration
            vertexDeclaration = new VertexDeclaration(new VertexElement[]
                {
                    new VertexElement(0, VertexElementFormat.Vector3, VertexElementUsage.Position, 0),
                    new VertexElement(12, VertexElementFormat.Vector3, VertexElementUsage.Normal, 0),
                    new VertexElement(24, VertexElementFormat.Vector2, VertexElementUsage.TextureCoordinate, 0)
                }
            );

            // Initialize the vertex buffer, allocating memory for each vertex.
            vertexBuffer = new VertexBuffer(graphics.GraphicsDevice,
                vertexDeclaration, vertices.Count, BufferUsage.None);

            // Set the vertex buffer data to the array of vertices.
            vertexBuffer.SetData(vertices.ToArray());

            // Create an index buffer, and copy our index data into it.
            indexBuffer = new IndexBuffer(graphics.GraphicsDevice, typeof(ushort),
                                          indices.Count, BufferUsage.None);
            indexBuffer.SetData(indices.ToArray());
}

void DrawPrimitive()
{
// 중간생략…
            // Set our vertex declaration, vertex buffer, and index buffer.
            graphics.GraphicsDevice.SetVertexBuffer(vertexBuffer);
            graphics.GraphicsDevice.Indices = indexBuffer;        

            foreach (EffectPass pass in basicEffect.CurrentTechnique.Passes)
            {
                pass.Apply();
                int primitiveCount = indices.Count / 3;
                graphics.GraphicsDevice.DrawIndexedPrimitives(
                    PrimitiveType.TriangleList, 0, 0, vertices.Count, 0, primitiveCount);
            }
}