Batching/Sorting accruacy test for SpriteBatch

SpriteDepthTest.cs

/* SpriteBatch Stress Test
 * Written by Ethan "flibitijibibo" Lee
 * http://www.flibitijibibo.com/
 *
 * Released under public domain.
 * No warranty implied; use at your own risk.
 */

using System;
using System.Diagnostics;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;

class SpriteBatchTest : Game
{
	private const int SPRITECOUNT = 2048;
	private const int TEXTURESIZE = 128;

	private SpriteSortMode mode = SpriteSortMode.BackToFront;

	private Texture2D box;
	private SpriteBatch batch;

	public SpriteBatchTest() : base()
	{
		new GraphicsDeviceManager(this);
	}

	protected override void Draw(GameTime gameTime)
	{
		GraphicsDevice.Clear(Color.Black);
		batch.Begin(mode, BlendState.Opaque);
		for (int i = 0; i < SPRITECOUNT; i += 1)
		{
			batch.Draw(
				box,
				Vector2.Zero,
				null,
				new Color(
					i / (float) SPRITECOUNT,
					0.0f,
					(SPRITECOUNT - i) / (float) SPRITECOUNT,
					1.0f
				),
				0.0f,
				Vector2.Zero,
				1.0f,
				SpriteEffects.None,
				i / (float) SPRITECOUNT
			);
		}
		batch.End();
	}

	protected override void Update(GameTime gameTime)
	{
		KeyboardState state = Keyboard.GetState();
		if (state.IsKeyDown(Keys.D1))
		{
			// Blue
			mode = SpriteSortMode.BackToFront;
		}
		else if (state.IsKeyDown(Keys.D2))
		{
			// Red
			mode = SpriteSortMode.FrontToBack;
		}
	}

	protected override void LoadContent()
	{
		Color[] color = new Color[TEXTURESIZE * TEXTURESIZE];
		for (int i = 0; i < color.Length; i += 1)
		{
			color[i] = Color.White;
		}
		box = new Texture2D(GraphicsDevice, TEXTURESIZE, TEXTURESIZE);
		box.SetData(color);
		batch = new SpriteBatch(GraphicsDevice);
	}

	protected override void UnloadContent()
	{
		batch.Dispose();
		batch = null;
		box.Dispose();
		box = null;
	}

	public static void Main(string[] args)
	{
		SpriteBatchTest game = new SpriteBatchTest();
		{
			game.Run();
		}
		game.Dispose();
	}
}