XNA 学习做的第一个小游戏 精灵追逐 （一）

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

        //threerings
        Texture2D ringTexture;
        Point ringCurrentFrame = new Point(0, 0);
        Point ringFrameSize = new Point(75, 75);
        Point ringSheetFrame = new Point(6, 8);

        int ringSincePerTime = 0;
        int ringWishDoTime = 50;

        Vector2 ringPosition = Vector2.Zero;
        //skullball
        Texture2D skullTexture;
        Point skullCurrentFrame = new Point(0, 0);
        Point skullFrameSize = new Point(75, 75);
        Point skullSheetFrame = new Point(6, 8);

        int skullSincePerTime = 0;
        int skullWishDoTime = 50;

        //plus
        Texture2D plusTexture;
        Point plusCurrentFrame = new Point(0, 0);
        Point plusFrameSize = new Point(75, 75);
        Point plusSheetFrame = new Point(6, 4);
        Vector2 plusPosition = Vector2.Zero;

        int plusSincePerTime = 0;
        int plusWishDoTime = 50;

        const int plusSpeed = 3;
        int plusSpeedX = plusSpeed;
        int plusSpeedY = plusSpeed;


        //mouse postion
        Point mousePerPosition = new Point(0,0);
        //move speed
        int ringSpeed = 6;

        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);

            // TODO: use this.Content to load your game content here
            ringTexture = Content.Load<Texture2D>(@"Images/threerings");
            skullTexture = Content.Load<Texture2D>(@"Images/skullball");
            plusTexture = Content.Load<Texture2D>(@"Images/plus");
        }

        /// <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
            //threerings
            ringSincePerTime += gameTime.ElapsedGameTime.Milliseconds;
            if (ringSincePerTime > ringWishDoTime)
            {
                ringSincePerTime = ringSincePerTime - ringWishDoTime;
                ++ringCurrentFrame.X;
                if (ringCurrentFrame.X > ringSheetFrame.X)
                {
                    ringCurrentFrame.X = 0;
                    ++ringCurrentFrame.Y;
                    if (ringCurrentFrame.Y > ringSheetFrame.Y)
                    {
                        ringCurrentFrame.Y = 0;
                    }
                }
            }
            //skullball
            skullSincePerTime += gameTime.ElapsedGameTime.Milliseconds;
            if (skullSincePerTime > skullWishDoTime)
            {
                skullSincePerTime = skullSincePerTime - skullWishDoTime;
                ++skullCurrentFrame.X;
                if (skullCurrentFrame.X > skullSheetFrame.X)
                {
                    skullCurrentFrame.X = 0;
                    ++skullCurrentFrame.Y;
                    if (skullCurrentFrame.Y > skullSheetFrame.Y)
                    {
                        skullCurrentFrame.Y = 0;
                    }
                }
            }

            //plus
            plusSincePerTime += gameTime.ElapsedGameTime.Milliseconds;
            if (plusSincePerTime > plusWishDoTime)
            {
                plusSincePerTime = plusSincePerTime - plusWishDoTime;
                ++plusCurrentFrame.X;
                if (plusCurrentFrame.X > plusSheetFrame.X)
                {
                    plusCurrentFrame.X = 0;
                    ++plusCurrentFrame.Y;
                    if (plusCurrentFrame.Y > plusSheetFrame.Y)
                    {
                        plusCurrentFrame.Y = 0;
                    }
                }

                //第二个精灵无规则运动
                //假如碰撞到右边
                if (plusPosition.X > plusFrameSize.X * plusSheetFrame.X)
                {
                    //设置当前位置为右边的临界点
                    plusPosition.X = plusFrameSize.X * plusSheetFrame.X;
                    //设置X横向运动速度为plusSpeed
                    plusSpeedX = plusSpeed;
                    //设置一个4到6的随机数，用于随机改变Y方向的速度
                    Random rd = new Random();
                    double sjs = Convert.ToInt32(rd.Next(4, 7)) * 0.1;
                    //zf用于设置Y轴运动的方向
                    bool zf = false;
                    if (sjs == 0.5)
                    {
                        zf = true;
                    }
                    if (sjs > 0.5)
                    {
                        if (zf)
                        {
                            plusSpeedY = (int)(plusSpeedX * sjs);
                        }
                        else
                        {
                            plusSpeedY = (int)(plusSpeedX / sjs);
                        }
                    }
                    else
                    {
                        if (zf)
                        {
                            plusSpeedY= -(int)(plusSpeedX * sjs);
                        }
                        else
                        {
                            plusSpeedY = -(int)(plusSpeedX / sjs);
                        }
                    }
                    //由于X轴右边碰撞，所以位置要加负值
                    plusSpeedX = -plusSpeedX;
                }
                else if (plusPosition.X < 0)
                {
                    plusPosition.X = 0;
                    plusSpeedX = plusSpeed;
                    Random rd = new Random();
                    double sjs = Convert.ToInt32(rd.Next(4, 7)) * 0.1;
                    bool zf = false;
                    if (sjs == 0.5)
                    {
                        zf = true;
                    }
                    if (sjs > 0.5)
                    {
                        if (zf)
                        {
                            plusSpeedY = (int)(plusSpeedX * sjs);
                        }
                        else
                        {
                            plusSpeedY = (int)(plusSpeedX / sjs);
                        }
                    }
                    else
                    {
                        if (zf)
                        {
                            plusSpeedY = -(int)(plusSpeedX * sjs);
                        }
                        else
                        {
                            plusSpeedY = -(int)(plusSpeedX / sjs);
                        }
                    }
                }
                else if (plusPosition.Y > plusFrameSize.Y * plusSheetFrame.Y)
                {
                    plusPosition.Y = plusFrameSize.Y * plusSheetFrame.Y;
                    plusSpeedY = plusSpeed;
                    Random rd = new Random();
                    double sjs = Convert.ToInt32(rd.Next(4, 7)) * 0.1;
                    bool zf = false;
                    if (sjs == 0.5)
                    {
                        zf = true;
                    }
                    if (sjs > 0.5)
                    {
                        if (zf)
                        {
                            plusSpeedX = (int)(plusSpeedY * sjs);
                        }
                        else
                        {
                            plusSpeedX = (int)(plusSpeedY / sjs);
                        }
                    }
                    else
                    {
                        if (zf)
                        {
                            plusSpeedX = -(int)(plusSpeedY * sjs);
                        }
                        else
                        {
                            plusSpeedX = -(int)(plusSpeedY / sjs);
                        }
                    }
                    plusSpeedY = -plusSpeedY;
                }
                else if (plusPosition.Y < 0)
                {
                    plusPosition.Y = 0;
                    plusSpeedY = plusSpeed;
                    Random rd = new Random();
                    double sjs = Convert.ToInt32(rd.Next(4, 7)) * 0.1;
                    bool zf = false;
                    if (sjs == 0.5)
                    {
                        zf = true;
                    }
                    if (sjs > 0.5)
                    {
                        if (zf)
                        {
                            plusSpeedX = (int)(plusSpeedY * sjs);
                        }
                        else
                        {
                            plusSpeedX = (int)(plusSpeedY / sjs);
                        }
                    }
                    else
                    {
                        if (zf)
                        {
                            plusSpeedX = -(int)(plusSpeedY * sjs);
                        }
                        else
                        {
                            plusSpeedX = -(int)(plusSpeedY / sjs);
                        }
                    }
                }

                plusPosition.X += plusSpeedX;
                plusPosition.Y += plusSpeedY;               


                //move skull
                KeyboardState keyboardState = Keyboard.GetState();
                if (keyboardState.IsKeyDown(Keys.Left))
                {
                    ringPosition.X -= ringSpeed;
                }
                if (keyboardState.IsKeyDown(Keys.Right))
                {
                    ringPosition.X += ringSpeed;
                }
                if (keyboardState.IsKeyDown(Keys.Up))
                {
                    ringPosition.Y -= ringSpeed;
                }
                if (keyboardState.IsKeyDown(Keys.Down))
                {
                    ringPosition.Y += ringSpeed;
                }

                MouseState mouseState = Mouse.GetState();
                Point mouseCurPosition = new Point(mouseState.X, mouseState.Y);
                if (mousePerPosition.X != mouseCurPosition.X || mousePerPosition.Y != mouseCurPosition.Y)
                {
                    ringPosition = new Vector2(mouseCurPosition.X, mouseCurPosition.Y);
                    mousePerPosition = mouseCurPosition;
                }

                if (ringPosition.X < 0)
                {
                    ringPosition.X = 0;
                }
                if (ringPosition.Y < 0)
                {
                    ringPosition.Y = 0;
                }
                if (ringPosition.X > ringFrameSize.X * ringSheetFrame.X)
                {
                    ringPosition.X = ringFrameSize.X * ringSheetFrame.X;
                }
                if (ringPosition.Y > ringFrameSize.Y * ringSheetFrame.Y)
                {
                    ringPosition.Y = ringFrameSize.Y * ringSheetFrame.Y;
                }
                //碰撞后退出
                if (collide() || collide2())
                {
                    this.Exit();
                }

                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(ringTexture, ringPosition,
                new Rectangle(ringCurrentFrame.X * ringFrameSize.X, ringCurrentFrame.Y * ringFrameSize.Y,
                    ringFrameSize.X, ringFrameSize.Y), Color.White, 0, Vector2.Zero, 1, SpriteEffects.None, 0);
            spriteBatch.Draw(skullTexture, new Vector2(100,100),
                new Rectangle(skullCurrentFrame.X * skullFrameSize.X, skullCurrentFrame.Y * skullFrameSize.Y, skullFrameSize.X, skullFrameSize.Y),
                Color.White, 0, Vector2.Zero, 1, SpriteEffects.None, 0);
            spriteBatch.Draw(plusTexture, plusPosition,
                new Rectangle(plusCurrentFrame.X * plusFrameSize.X, plusCurrentFrame.Y * plusFrameSize.Y, plusFrameSize.X, plusFrameSize.Y),
                Color.White, 0, Vector2.Zero, 1, SpriteEffects.None, 0);
            spriteBatch.End();
            base.Draw(gameTime);
        }

        protected bool collide()
        {
            //精灵于骷髅碰撞检测
            Rectangle ringRect = new Rectangle((int)ringPosition.X , (int)ringPosition.Y , (int)ringFrameSize.X - 20, (int)ringFrameSize.Y - 20);
            Rectangle skullRect = new Rectangle(100 ,100 , (int)skullFrameSize.X - 20, (int)skullFrameSize.Y - 20);
            return ringRect.Intersects(skullRect);
        }
        //检测动态精灵碰撞
        protected bool collide2()
        {
            Rectangle ringRect = new Rectangle((int)ringPosition.X, (int)ringPosition.Y, (int)ringFrameSize.X - 20, (int)ringFrameSize.Y - 20);
            Rectangle plusRect = new Rectangle((int)plusPosition.X, (int)plusPosition.Y, (int)plusFrameSize.X, (int)plusFrameSize.Y);
            return ringRect.Intersects(plusRect);
        }
    }
}

　　plus.png:

threerings.png:

skullball.png

运行效果：plus随机运动，碰到墙壁后返回。

thrrerings可以使用鼠标和键盘的方向键控制运动，碰到追逐它的精灵和炸弹后，游戏退出。