XNA Showroom

Program.cs

/*
 * Program.cs
 *
 * Copyright 2012 Roberto Estrada
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 3 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
using System;

namespace XNAShowRoom
{
#if WINDOWS || XBOX
    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        static void Main(string[] args)
        {
            using (ShowRoom game = new ShowRoom())
            {
                game.Run();
            }
        }
    }
#endif
}

ShowRoom.cs

/*
 * ShowRoom.cs
 *
 * Copyright 2012 Roberto Estrada
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 3 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

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 XNAShowRoom
{
    /// <summary>
    /// The 3D XNA Showroom 
    /// </summary>
    public class ShowRoom : Microsoft.Xna.Framework.Game
    {
        // Field of view
        static float FOV = 60.0f;

        // Graphics adapter variables
        float aspectRatio;
        GraphicsDeviceManager graphics;
        SpriteBatch spriteBatch;
        
        // Model to be shown
        Model shownModel;
        // Position of the model (X, Y, Z)
        Vector3 modelPos;
        // Model rotation (in degrees)
        float modelRotation;

        // Camera position in world
        Vector3 cameraPos;
        Matrix lookAtMatrix;
        Matrix projectionMatrix;

        public ShowRoom()
        {
            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);
            // Getting viewport aspect ratio
            aspectRatio = graphics.GraphicsDevice.Viewport.AspectRatio;
            // Content loading
            shownModel = Content.Load<Model>("Models\\desklamp");
            // Setting camera
            cameraPos = new Vector3(0.0f, 100.0f, 80.0f);
            // Matrix precomputation
            lookAtMatrix = Matrix.CreateLookAt(cameraPos, new Vector3(0.0f, 50.0f, 0.0f), Vector3.Up);
            projectionMatrix = Matrix.CreatePerspectiveFieldOfView(MathHelper.ToRadians(FOV), aspectRatio, 1.0f, 10000.0f);
        }

        /// <summary>
        /// UnloadContent will be called once per game and is the place to unload
        /// all content.
        /// </summary>
        protected override void UnloadContent()
        {
            // No unmanaged contents to unload
        }

        /// <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();

            modelRotation += (float)gameTime.ElapsedGameTime.TotalMilliseconds *
            MathHelper.ToRadians(0.01f);

            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);

            // Drawing code
            Matrix[] transformBoneMatrixes = new Matrix[shownModel.Bones.Count];
            shownModel.CopyAbsoluteBoneTransformsTo(transformBoneMatrixes);

            // Model draw, for each mesh in the model...
            foreach (ModelMesh mesh in shownModel.Meshes)
            {
                foreach (BasicEffect effect in mesh.Effects)
                {
                    effect.EnableDefaultLighting();
                    effect.World = transformBoneMatrixes[mesh.ParentBone.Index] *
                                   Matrix.CreateRotationY(modelRotation) * 
                                   Matrix.CreateTranslation(modelPos);
                    effect.View = lookAtMatrix;
                    effect.Projection = projectionMatrix;
                }
                mesh.Draw();
            }

            base.Draw(gameTime);
        }
    }
}