SpriteBatchとModel

■SpriteBatchとModelを同時に表示したら、ポリゴンのソートがおかしくなりました。

namespace WindowsGame2_13
{
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics;
        private double dAng = 0;
        private Model model;
        private Matrix mainView;
        private Matrix mainWorld;
        private Matrix mainProjection;
        private SpriteBatch sprite;
        private Texture2D texture;

        public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
        }
        protected override void Initialize()
        {
            model = Content.Load<Model>("Box");
            mainProjection = Matrix.CreatePerspectiveFieldOfView(
                    MathHelper.ToRadians(45.0f),
                    (float)graphics.GraphicsDevice.Viewport.Width / (float)graphics.GraphicsDevice.Viewport.Height,
                    1.0f,
                    100.0f
                );
            base.Initialize();
        }

        protected override void LoadContent()
        {
            sprite = new SpriteBatch(graphics.GraphicsDevice);
            texture = Content.Load<Texture2D>("mimi");
        }
        protected override void Update(GameTime gameTime)
        {
            // ビューマトリックス
            mainView = Matrix.CreateLookAt(
                    new Vector3((float)(10.0 * Math.Sin(dAng)), 5.0f, (float)(10.0 * Math.Cos(dAng))),
                    new Vector3(0, 0, 0),
                    Vector3.Up
                );
            dAng += 0.01;
            if (dAng > 3.141592 * 2)
                dAng -= 3.141592 * 2;
            //-----------------------
            base.Update(gameTime);
        }

        protected override void Draw(GameTime gameTime)
        {
            graphics.GraphicsDevice.Clear(Color.CornflowerBlue);

            sprite.Begin();
            Vector2 pos = new Vector2(0, 0);
            sprite.Draw(texture, pos, Color.White);
            sprite.End();

            for (int j = -1; j < 2; j++)
            {
                for (int i = -1; i < 2; i++)
                {
                    mainWorld = Matrix.CreateTranslation(i * 2.5f, 0, j * 2.5f);
                    foreach (ModelMesh mesh in model.Meshes)
                    {
                        foreach (BasicEffect effect in mesh.Effects)
                        {
                            effect.View = mainView;
                            effect.Projection = mainProjection;
                            effect.World = mainWorld;
                        }
                        mesh.Draw();
                    }
                }
            }
            base.Draw(gameTime);
        }
    }
}

デプスが無効化している事が問題なので

protected override void Draw(GameTime gameTime)
{
    graphics.GraphicsDevice.Clear(Color.CornflowerBlue);
    sprite.Begin();
    Vector2 pos = new Vector2(0, 0);
    sprite.Draw(texture, pos, Color.White);
    sprite.End();

    graphics.GraphicsDevice.RenderState.DepthBufferEnable = true;
    for (int j = -1; j < 2; j++)
    {
        for (int i = -1; i < 2; i++)
        {
            mainWorld = Matrix.CreateTranslation(i * 2.5f, 0, j * 2.5f);
            foreach (ModelMesh mesh in model.Meshes)
            {
                foreach (BasicEffect effect in mesh.Effects)
                {
                    effect.View = mainView;
                    effect.Projection = mainProjection;
                    effect.World = mainWorld;
                }
                mesh.Draw();
            }
        }
    }
    base.Draw(gameTime);
}

とし、この一行を入れる事で解決です。

graphics.GraphicsDevice.RenderState.DepthBufferEnable = true;

「SpriteBatch」の中で　GraphicsDevice　の設定を変えているのを思い出しました。詳しくは
http://blogs.msdn.com/ito/archive/2007/03/13/spritebatch-part2.aspx
参考をにしました。　感謝、感謝