XNA实践鼠标篇--根据点击坐标移动图片（四）下

/// <summary>
/// This is the main type for your game
/// </summary>
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
/// <summary>
/// 图片的位置
/// </summary>
private Vector2 picPosition;
/// <summary>
/// 当前鼠标点击的位置
/// </summary>
private Vector2 CurrentPosition;

/// <summary>
/// 移动因子
/// </summary>
private Vector2 MovePix;
/// <summary>
/// 定义2D的纹理图片
/// </summary>
private Texture2D texture;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
IsMouseVisible = true;//显示鼠标
//初始化鼠标点击游戏界面的坐标
picPosition = new Vector2();
MovePix = new Vector2(1.0f, 1.0f);//移动一个像素
}

/// <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);
texture = Texture2D.FromFile(graphics.GraphicsDevice, "test.jpg");
// 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();

MouseState mouseState = Mouse.GetState();
if (mouseState.LeftButton == ButtonState.Pressed)
{
Viewport vp = graphics.GraphicsDevice.Viewport;//获取视窗
if (mouseState.X < vp.X || mouseState.X > vp.X + vp.Width || mouseState.Y < vp.Y || mouseState.Y > vp.Y + vp.Height)
{
//点击坐标不在窗体内就不管了
}
else
{
if (CurrentPosition.X != mouseState.X || CurrentPosition.Y != mouseState.Y)
{
CurrentPosition.X = mouseState.X;
CurrentPosition.Y = mouseState.Y;
}
}
}
Mover();

// TODO: Add your update logic here

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
spriteBatch.Begin();
spriteBatch.Draw(texture, picPosition, Color.White);
spriteBatch.End();
base.Draw(gameTime);
}
/// <summary>
/// 开始移动
/// </summary>
void Mover()
{
Vector2 v = picPosition - CurrentPosition;//向量相减
if (v.X > 0)
picPosition.X -= MovePix.X;//向左移动
else if (v.X + texture.Width  < 0)
picPosition.X += MovePix.X;//向右移动
if (v.Y > 0)
picPosition.Y -= MovePix.Y;//向上移动
else if (v.Y + texture.Height < 0)
picPosition.Y += MovePix.Y;//向一移动
}
}

图片还是使用上次的2维图片，现在在非图片覆盖区按住鼠标的左键并移动鼠标看看，图片是不是跟着鼠标的方向慢慢移动了，看到这里，大家会想到什么了么？

对了，就是游戏中的角色对怪的位置跟踪，但在这张图上只体现了F(G+H)，因为窗体没有任何的障碍物。