#region File Description
//-----------------------------------------------------------------------------
// CustomModelEffect.cs
//
// Microsoft XNA Community Game Platform
// Copyright (C) Microsoft Corporation. All rights reserved.
//-----------------------------------------------------------------------------
#endregion

#region Using Statements
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
#endregion

namespace CustomModelEffect
{
    /// <summary>
    /// Sample shows how to render a model using a custom effect.
    /// </summary>
    public class CustomModelEffectGame : Microsoft.Xna.Framework.Game
    {
        #region Fields

        GraphicsDeviceManager graphics;

        Model model;

        #endregion

        #region Initialization


        public CustomModelEffectGame()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
        }


        /// <summary>
        /// Load your graphics content.
        /// </summary>
        protected override void LoadContent()
        {
            model = Content.Load<Model>("saucer");
        }


        #endregion

        #region Update and Draw


        /// <summary>
        /// Allows the game to run logic.
        /// </summary>
        protected override void Update(GameTime gameTime)
        {
            HandleInput();

            base.Update(gameTime);
        }


        /// <summary>
        /// This is called when the game should draw itself.
        /// </summary>
        protected override void Draw(GameTime gameTime)
        {
            GraphicsDevice device = graphics.GraphicsDevice;

            device.Clear(Color.CornflowerBlue);

            // Calculate the camera matrices.
            Viewport viewport = device.Viewport;

            float aspectRatio = (float)viewport.Width / (float)viewport.Height;

            float time = (float)gameTime.TotalGameTime.TotalSeconds;

            Matrix rotation = Matrix.CreateRotationX(time * 0.3f) *
                              Matrix.CreateRotationY(time);

            Matrix view = Matrix.CreateLookAt(new Vector3(4000, 0, 0),
                                              Vector3.Zero,
                                              Vector3.Up);

            Matrix projection = Matrix.CreatePerspectiveFieldOfView(MathHelper.PiOver4,
                                                                    aspectRatio,
                                                                    10, 10000);

            // Draw the model.
            Matrix[] transforms = new Matrix[model.Bones.Count];

            model.CopyAbsoluteBoneTransformsTo(transforms);

            foreach (ModelMesh mesh in model.Meshes)
            {
                foreach (Effect effect in mesh.Effects)
                {
                    Matrix world = transforms[mesh.ParentBone.Index] * rotation;

                    effect.Parameters["World"].SetValue(world);
                    effect.Parameters["View"].SetValue(view);
                    effect.Parameters["Projection"].SetValue(projection);
                }

                mesh.Draw();
            }

            base.Draw(gameTime);
        }


        #endregion

        #region Handle Input


        /// <summary>
        /// Handles input for quitting the game.
        /// </summary>
        private void HandleInput()
        {
            KeyboardState currentKeyboardState = Keyboard.GetState();
            GamePadState currentGamePadState = GamePad.GetState(PlayerIndex.One);

            // Check for exit.
            if (currentKeyboardState.IsKeyDown(Keys.Escape) ||
                currentGamePadState.Buttons.Back == ButtonState.Pressed)
            {
                Exit();
            }
        }


        #endregion
    }


    #region Entry Point

    /// <summary>
    /// The main entry point for the application.
    /// </summary>
    static class Program
    {
        static void Main()
        {
            using (CustomModelEffectGame game = new CustomModelEffectGame())
            {
                game.Run();
            }
        }
    }

    #endregion
}