xna 精灵动起来

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;

namespace WindowsGame1
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics; 
        SpriteBatch spriteBatch;

        Texture2D texture;
        Texture2D textureTransparent;
        Vector2 pos1 = Vector2.Zero;
        Vector2 pos2 = Vector2.Zero;
        float speed1 = 2f;
        float speed2 = 3f;
        
        public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
        }

        /// <summary>
        /// Allows the game to perform any initialization it needs to before starting to run.
        /// This is where it can query for any required services and load any non-graphic
        /// related content.  Calling base.Initialize will enumerate through any components
        /// and initialize them as well.
        /// </summary>
        protected override void Initialize()
        {
            // TODO: Add your initialization logic here

            base.Initialize();
        }

        /// <summary>
        /// LoadContent will be called once per game and is the place to load
        /// all of your content.
        /// </summary>
        protected override void LoadContent()
        {
            // Create a new SpriteBatch, which can be used to draw textures.
            spriteBatch = new SpriteBatch(GraphicsDevice);

            //@表示忽略转义字符
            texture = Content.Load<Texture2D>(@"Images/logo");
            textureTransparent = Content.Load<Texture2D>(@"Images/logo_trans");
            // TODO: use this.Content to load your game content here
        }

        /// <summary>
        /// UnloadContent will be called once per game and is the place to unload
        /// all content.
        /// </summary>
        protected override void UnloadContent()
        {
            // TODO: Unload any non ContentManager content here
        }

        /// <summary>
        /// Allows the game to run logic such as updating the world,
        /// checking for collisions, gathering input, and playing audio.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Update(GameTime gameTime)
        {
            // Allows the game to exit
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
                this.Exit();

            // TODO: Add your update logic here
            pos1.X += speed1;
            if (pos1.X>Window.ClientBounds.Width-texture.Width||
                pos1.X<0)
                speed1*=-1;

            
            pos2.Y += speed2;
            if (pos2.Y > Window.ClientBounds.Height - textureTransparent.Height ||
                pos2.Y < 0)
                speed2 *= -1;
            


            base.Update(gameTime);
        }

        /// <summary>
        /// This is called when the game should draw itself.
        /// </summary>
        /// <param name="gameTime">Provides a snapshot of timing values.</param>
        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice.Clear(Color.CornflowerBlue);

            // TODO: Add your drawing code here
            //通知显卡开始传送文件
            //从左上角开始绘制
            //white表示不会染色
            spriteBatch.Begin();
            //spriteBatch.Draw(texture, Vector2.Zero, Color.White);
            spriteBatch.Draw(texture, 
                pos1,
                null,
                Color.White,
                0,
                Vector2.Zero,
                1,
                SpriteEffects.None,
                0);

            spriteBatch.Draw(textureTransparent,
                pos2,
                null,
                Color.White,
                0,
                Vector2.Zero,
                1,
                SpriteEffects.None,
                1);
            spriteBatch.End();
            


            base.Draw(gameTime);
        }
    }
}