2010/12/17 3D 視角 飛彈

using System;
using System.Collections.Generic;
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.Net;
using Microsoft.Xna.Framework.Storage;

namespace GoingBeyond1_Tutorial
{
    /// <summary>
    /// This is the main type for your game
    /// </summary>
    public class Game1 : Microsoft.Xna.Framework.Game
    {
        GraphicsDeviceManager graphics;
        SpriteBatch spriteBatch;

        GameObject terrain = new GameObject();
        GameObject missileLauncherBase = new GameObject();
        GameObject missileLauncherHead = new GameObject();

        const int numMissiles = 20;
        GameObject[] missiles;

        KeyboardState previousKeyboardState;
       

        const float launcherHeadMuzzleOffset = 20.0f;
        const float missilePower = 20.0f;

        //SoundBank soundBank;

        Vector3 cameraPosition = new Vector3(0.0f, 60.0f, 160.0f);
        Vector3 cameraLookAt = new Vector3(0.0f, 50.0f, 0.0f);
        Matrix cameraProjectionMatrix;
        Matrix cameraViewMatrix;

        // Set the position of the model in world space, and set the rotation.
        Vector3 modelPosition = Vector3.Zero;
        float modelRotation = 0.0f;

        // Set the position of the camera in world space, for our view matrix.
        //Vector3 cameraPosition = new Vector3(0.0f, 50.0f, 5000.0f);
        public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
        }

        protected override void Initialize()
        {
            base.Initialize();
        }

        // Set the 3D model to draw.
        Model myModel;

        // The aspect ratio determines how to scale 3d to 2d projection.
        float aspectRatio;

        protected override void LoadContent()
        {
            // Create a new SpriteBatch, which can be used to draw textures.
            spriteBatch = new SpriteBatch(GraphicsDevice);

            myModel = Content.Load<Model>("Models\\p1_wedge");
            aspectRatio = (float)graphics.GraphicsDevice.Viewport.Width /
            (float)graphics.GraphicsDevice.Viewport.Height;

            cameraViewMatrix = Matrix.CreateLookAt(
                cameraPosition,
                cameraLookAt,
                Vector3.Up);

            cameraProjectionMatrix = Matrix.CreatePerspectiveFieldOfView(
                MathHelper.ToRadians(45.0f),
                graphics.GraphicsDevice.Viewport.AspectRatio,
                1.0f,
                10000.0f);

            missileLauncherBase.model = Content.Load<Model>(
                "Models\\p1_wedge");
            missileLauncherBase.scale = 0.2f;
            missiles = new GameObject[numMissiles];

            for (int i = 0; i < numMissiles; i++)
            {
                missiles[i] = new GameObject();
                missiles[i].model =
                    Content.Load<Model>("Models\\missile");
                missiles[i].scale = 3.0f;
            }

        }

        protected override void UnloadContent()
        {

        }
      
        protected override void Update(GameTime gameTime)
        {
            // Allows the game to exit
            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
                this.Exit();

            //modelRotation += (float)gameTime.ElapsedGameTime.TotalMilliseconds * MathHelper.ToRadians(0.1f);
            KeyboardState keyboardState = Keyboard.GetState();
            if (keyboardState.IsKeyDown(Keys.Left))
            {
                missileLauncherHead.rotation.Y += 0.05f;
            }
            if (keyboardState.IsKeyDown(Keys.Right))
            {
                missileLauncherHead.rotation.Y -= 0.05f;
            }
            if (keyboardState.IsKeyDown(Keys.Up))
            {
                missileLauncherHead.rotation.X += 0.05f;
            }
            if (keyboardState.IsKeyDown(Keys.Down))
            {
                missileLauncherHead.rotation.X -= 0.05f;
            }

            if (keyboardState.IsKeyDown(Keys.Space) &&
              previousKeyboardState.IsKeyUp(Keys.Space))
            {
                FireMissile();
                //modelRotation += (float)gameTime.ElapsedGameTime.TotalMilliseconds * MathHelper.ToRadians(0.1f);
            }
            if (keyboardState.IsKeyDown(Keys.D) &&
               previousKeyboardState.IsKeyUp(Keys.D))
            {
               
                modelRotation += (float)gameTime.ElapsedGameTime.TotalMilliseconds * MathHelper.ToRadians(0.1f);
            }
            UpdateMissiles();

            previousKeyboardState = keyboardState;

            base.Update(gameTime);
        }
        void FireMissile()
        {
            foreach (GameObject missile in missiles)
            {
                if (!missile.alive)
                {
                    //soundBank.PlayCue("missilelaunch");

                    missile.velocity = GetMissileMuzzleVelocity();
                    missile.position = GetMissileMuzzlePosition();
                    missile.rotation = missileLauncherHead.rotation;
                    missile.alive = true;
                    break;
                }
            }
        }
        Vector3 GetMissileMuzzleVelocity()
        {
            Matrix rotationMatrix =
                Matrix.CreateFromYawPitchRoll(
                missileLauncherHead.rotation.Y,
                missileLauncherHead.rotation.X,
                0);

            return Vector3.Normalize(
                Vector3.Transform(Vector3.Forward,
                rotationMatrix)) * missilePower;
        }
        Vector3 GetMissileMuzzlePosition()
        {
            return missileLauncherHead.position +
                (Vector3.Normalize(
                GetMissileMuzzleVelocity()) *
                launcherHeadMuzzleOffset);
        }
        void UpdateMissiles()
        {
            foreach (GameObject missile in missiles)
            {
                if (missile.alive)
                {
                    missile.position += missile.velocity;
                    if (missile.position.Z < -6000.0f)
                    {
                        missile.alive = false;
                    }
                    else
                    {
                        TestCollision(missile);
                    }
                }
            }
        }
        void TestCollision(GameObject missile)
        {
            BoundingSphere missilesphere =
                missile.model.Meshes[0].BoundingSphere;
            missilesphere.Center = missile.position;
            missilesphere.Radius *= missile.scale;

           /* foreach (GameObject ship in enemyShips)
            {
                if (ship.alive)
                {
                    BoundingSphere shipsphere =
                        ship.model.Meshes[0].BoundingSphere;
                    shipsphere.Center = ship.position;
                    shipsphere.Radius *= ship.scale;

                    if (shipsphere.Intersects(missilesphere))
                    {
                        soundBank.PlayCue("explosion");
                        missile.alive = false;
                        ship.alive = false;
                        break;
                    }
                }
            }*/
        }
        protected override void Draw(GameTime gameTime)
        {
            graphics.GraphicsDevice.Clear(Color.CornflowerBlue);

            // Copy any parent transforms.
            Matrix[] transforms = new Matrix[myModel.Bones.Count];
            myModel.CopyAbsoluteBoneTransformsTo(transforms);

            // Draw the model. A model can have multiple meshes, so loop.
            foreach (ModelMesh mesh in myModel.Meshes)
            {
                // This is where the mesh orientation is set, as well as our camera and projection.
                foreach (BasicEffect effect in mesh.Effects)
                {
                    effect.EnableDefaultLighting();
                    effect.World = transforms[mesh.ParentBone.Index] * Matrix.CreateRotationY(modelRotation)
                        * Matrix.CreateTranslation(modelPosition);
                    effect.View = Matrix.CreateLookAt(cameraPosition, Vector3.Zero, Vector3.Up);
                    effect.Projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(45.0f),
                        aspectRatio, 1.0f, 10000.0f);
                }
                // Draw the mesh, using the effects set above.
                mesh.Draw();
            }
            foreach (GameObject missile in missiles)
            {
                if (missile.alive)
                {
                    DrawGameObject(missile);
                }
            }
                base.Draw(gameTime);
        }
        void DrawGameObject(GameObject gameobject)
        {
            foreach (ModelMesh mesh in gameobject.model.Meshes)
            {
                foreach (BasicEffect effect in mesh.Effects)
                {
                    effect.EnableDefaultLighting();
                    effect.PreferPerPixelLighting = true;

                    effect.World =
                        Matrix.CreateFromYawPitchRoll(
                        gameobject.rotation.Y,
                        gameobject.rotation.X,
                        gameobject.rotation.Z) *

                        Matrix.CreateScale(gameobject.scale) *

                        Matrix.CreateTranslation(gameobject.position);

                    effect.Projection = cameraProjectionMatrix;
                    effect.View = cameraViewMatrix;
                }
                mesh.Draw();
            }
        }
    }
}