/// <summary>
        /// Function to validate and update texture loading options.
        /// </summary>
        /// <param name="name">The name of the texture.</param>
        /// <param name="options">The options passed in by the user.</param>
        /// <returns>The updated texture loading options.</returns>
        private static GorgonTexture2DLoadOptions GetTextureOptions(string name, GorgonTexture2DLoadOptions options)
        {
            if (options == null)
            {
                options = _defaultLoadOptions;
            }

            options.Name     = name;
            options.Binding &= ~TextureBinding.DepthStencil;

            if ((options.Binding & TextureBinding.ShaderResource) != TextureBinding.ShaderResource)
            {
                options.Binding |= TextureBinding.ShaderResource;
            }

            if ((options.Usage != ResourceUsage.Immutable) && (options.Usage != ResourceUsage.Default))
            {
                options.Usage = ResourceUsage.Default;
            }

            return(options);
        }
        /// <summary>
        /// Function to load a <see cref="IGorgonAnimation"/> from a <see cref="GorgonFileSystem"/>.
        /// </summary>
        /// <param name="fileSystem">The file system to load the animation from.</param>
        /// <param name="renderer">The renderer for the animation.</param>
        /// <param name="path">The path to the animation file in the file system.</param>
        /// <param name="textureOptions">[Optional] Options for the texture loaded associated the sprite.</param>
        /// <param name="animationCodecs">The list of animation codecs to try and load the animation with.</param>
        /// <param name="imageCodecs">The list of image codecs to try and load the animation texture(s) with.</param>
        /// <returns>The animation data in the file as a <see cref="IGorgonAnimation"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when the <paramref name="fileSystem"/>, <paramref name="renderer"/>, or <paramref name="path"/> parameter is <b>null</b>.</exception>
        /// <exception cref="ArgumentEmptyException">Thrown when the <paramref name="path"/> parameter is empty.</exception>
        /// <exception cref="FileNotFoundException">Thrown if the file in the <paramref name="path"/> was not found.</exception>
        /// <exception cref="GorgonException">Thrown if the animation data in the file system could not be loaded because a suitable codec was not found.</exception>
        /// <remarks>
        /// <para>
        /// This method extends a <see cref="GorgonFileSystem"/> so that animations can be loaded by calling a method on the file system object itself. This negates the need for users to create complex code
        /// for loading an animation.
        /// </para>
        /// <para>
        /// When loading an animation, the method will attempt to locate any <see cref="GorgonTexture2DView"/> objects associated with the animation (if they exist). When loading, it will check:
        /// <list type="number">
        ///     <item>
        ///         <description>For a texture resource with the same name that is already loaded into memory.</description>
        ///     </item>
        ///     <item>
        ///         <description>Use the local <see cref="IGorgonVirtualDirectory"/> for the sprite file and search for the texture in that directory.</description>
        ///     </item>
        ///     <item>
        ///         <description>Check the entire <paramref name="fileSystem"/> for a file if the texture name contains path information (this is done by the GorgonEditor from v2).</description>
        ///     </item>
        /// </list>
        /// If the file is found, and can be loaded by one of the <paramref name="imageCodecs"/>, then it is loaded and assigned to the sprite.
        /// </para>
        /// <para>
        /// The <paramref name="animationCodecs"/> is a list of codecs for loading sprite data. If the user specifies this parameter, the only the codecs provided will be used for determining if an
        /// animation can be read. If it is not supplied, then all built-in (i.e. not plug in based) sprite codecs will be used.
        /// </para>
        /// <para>
        /// The <paramref name="imageCodecs"/> is a list of codecs for loading image data. If the user specifies this parameter, the only the codecs provided will be used for determining if an image can be
        /// read. If it is not supplied, then all built-in (i.e. not plug in based) image codecs will be used.
        /// </para>
        /// </remarks>
        /// <seealso cref="GorgonFileSystem"/>
        /// <seealso cref="GorgonTexture2DView"/>
        /// <seealso cref="IGorgonAnimation"/>
        public static IGorgonAnimation LoadAnimationFromFileSystem(this GorgonFileSystem fileSystem,
                                                                   Gorgon2D renderer,
                                                                   string path,
                                                                   GorgonTexture2DLoadOptions textureOptions           = null,
                                                                   IEnumerable <IGorgonAnimationCodec> animationCodecs = null,
                                                                   IEnumerable <IGorgonImageCodec> imageCodecs         = null)
        {
            if (fileSystem == null)
            {
                throw new ArgumentNullException(nameof(fileSystem));
            }

            IGorgonVirtualFile file = fileSystem.GetFile(path);

            if (file == null)
            {
                throw new FileNotFoundException(string.Format(Resources.GOR2DIO_ERR_FILE_NOT_FOUND, path));
            }

            if ((imageCodecs == null) || (!imageCodecs.Any()))
            {
                // If we don't specify any codecs, then use the built in ones.
                imageCodecs = new IGorgonImageCodec[]
                {
                    new GorgonCodecPng(),
                    new GorgonCodecBmp(),
                    new GorgonCodecDds(),
                    new GorgonCodecGif(),
                    new GorgonCodecJpeg(),
                    new GorgonCodecTga(),
                };
            }
            else
            {
                // Only use codecs that can decode image data.
                imageCodecs = imageCodecs.Where(item => item.CanDecode);
            }

            if ((animationCodecs == null) || (!animationCodecs.Any()))
            {
                // Use all built-in codecs if we haven't asked for any.
                animationCodecs = new IGorgonAnimationCodec[]
                {
                    new GorgonV3AnimationBinaryCodec(renderer),
                    new GorgonV3AnimationJsonCodec(renderer),
                    new GorgonV1AnimationCodec(renderer)
                };
            }
            else
            {
                // Only use codecs that can decode sprite data.
                animationCodecs = animationCodecs.Where(item => item.CanDecode);
            }

            Stream animStream = file.OpenStream();

            try
            {
                if (!animStream.CanSeek)
                {
                    Stream newStream = new DataStream((int)animStream.Length, true, true);
                    animStream.CopyTo(newStream);
                    newStream.Position = 0;

                    animStream.Dispose();
                    animStream = newStream;
                }

                IGorgonAnimationCodec animationCodec = GetAnimationCodec(animStream, animationCodecs);

                if (animationCodec == null)
                {
                    throw new GorgonException(GorgonResult.CannotRead, string.Format(Resources.GOR2DIO_ERR_NO_SUITABLE_ANIM_CODEC_FOUND, path));
                }

                // Load the animation.
                IGorgonAnimation animation = animationCodec.FromStream(animStream, (int)file.Size);

                // We have no textures to update, leave.
                if (animation.Texture2DTrack.KeyFrames.Count == 0)
                {
                    return(animation);
                }

                // Try to locate the textures.

                // V1 sprite animations need texture coordinate correction.
                bool needsCoordinateFix = animationCodec is GorgonV1AnimationCodec;

                foreach (GorgonKeyTexture2D textureKey in animation.Texture2DTrack.KeyFrames)
                {
                    // Let's try and load the texture into memory.
                    // This does this by:
                    // 1. Checking to see if a texture resource with the name specified is already available in memory.
                    // 2. Checking the local directory of the file to see if the texture is there.
                    // 3. A file system wide search.

                    // ReSharper disable once InvertIf
                    (IGorgonImageCodec codec, IGorgonVirtualFile textureFile, bool loaded) =
                        LocateTextureCodecAndFile(fileSystem, file.Directory, renderer, textureKey.TextureName, imageCodecs);

                    // We have not loaded the texture yet.  Do so now.
                    // ReSharper disable once InvertIf
                    if ((!loaded) && (textureFile != null) && (codec != null))
                    {
                        using (Stream textureStream = textureFile.OpenStream())
                        {
                            textureKey.Value = GorgonTexture2DView.FromStream(renderer.Graphics,
                                                                              textureStream,
                                                                              codec,
                                                                              textureFile.Size, GetTextureOptions(textureFile.FullPath, textureOptions));
                        }
                    }

                    if ((needsCoordinateFix) && (textureKey.Value != null))
                    {
                        textureKey.TextureCoordinates = new RectangleF(textureKey.TextureCoordinates.X / textureKey.Value.Width,
                                                                       textureKey.TextureCoordinates.Y / textureKey.Value.Height,
                                                                       textureKey.TextureCoordinates.Width / textureKey.Value.Width,
                                                                       textureKey.TextureCoordinates.Height / textureKey.Value.Height);
                    }
                }

                return(animation);
            }
            finally
            {
                animStream?.Dispose();
            }
        }
        /// <summary>
        /// Function to load a <see cref="GorgonPolySprite"/> from a <see cref="GorgonFileSystem"/>.
        /// </summary>
        /// <param name="fileSystem">The file system to load the sprite from.</param>
        /// <param name="renderer">The renderer for the sprite.</param>
        /// <param name="path">The path to the sprite file in the file system.</param>
        /// <param name="textureOptions">[Optional] Options for the texture loaded associated the sprite.</param>
        /// <param name="spriteCodecs">The list of polygonal sprite codecs to try and load the sprite with.</param>
        /// <param name="imageCodecs">The list of image codecs to try and load the sprite texture with.</param>
        /// <returns>The sprite data in the file as a <see cref="GorgonSprite"/>.</returns>
        /// <exception cref="ArgumentNullException">Thrown when the <paramref name="fileSystem"/>, <paramref name="renderer"/>, or <paramref name="path"/> parameter is <b>null</b>.</exception>
        /// <exception cref="ArgumentEmptyException">Thrown when the <paramref name="path"/> parameter is empty.</exception>
        /// <exception cref="FileNotFoundException">Thrown if the file in the <paramref name="path"/> was not found.</exception>
        /// <exception cref="GorgonException">Thrown if the sprite data in the file system could not be loaded because a suitable codec was not found.</exception>
        /// <remarks>
        /// <para>
        /// This method extends a <see cref="GorgonFileSystem"/> so that sprites can be loaded by calling a method on the file system object itself. This negates the need for users to create complex code
        /// for loading a sprite.
        /// </para>
        /// <para>
        /// When loading a sprite, the method will attempt to locate the <see cref="GorgonTexture2DView"/> associated with the sprite (if it exists). When loading, it will check:
        /// <list type="number">
        ///     <item>
        ///         <description>For a texture resource with the same name that is already loaded into memory.</description>
        ///     </item>
        ///     <item>
        ///         <description>Use the local <see cref="IGorgonVirtualDirectory"/> for the sprite file and search for the texture in that directory.</description>
        ///     </item>
        ///     <item>
        ///         <description>Check the entire <paramref name="fileSystem"/> for a file if the texture name contains path information (this is done by the GorgonEditor from v2).</description>
        ///     </item>
        /// </list>
        /// If the file is found, and can be loaded by one of the <paramref name="imageCodecs"/>, then it is loaded and assigned to the sprite.
        /// </para>
        /// <para>
        /// The <paramref name="spriteCodecs"/> is a list of codecs for loading polygonal sprite data. If the user specifies this parameter, the only the codecs provided will be used for determining if a
        /// sprite can be read. If it is not supplied, then all built-in (i.e. not plug in based) sprite codecs will be used.
        /// </para>
        /// <para>
        /// The <paramref name="imageCodecs"/> is a list of codecs for loading image data. If the user specifies this parameter, the only the codecs provided will be used for determining if an image can be
        /// read. If it is not supplied, then all built-in (i.e. not plug in based) image codecs will be used.
        /// </para>
        /// </remarks>
        /// <seealso cref="GorgonFileSystem"/>
        /// <seealso cref="GorgonTexture2DView"/>
        /// <seealso cref="GorgonPolySprite"/>
        public static GorgonPolySprite LoadPolySpriteFromFileSystem(this GorgonFileSystem fileSystem,
                                                                    Gorgon2D renderer,
                                                                    string path,
                                                                    GorgonTexture2DLoadOptions textureOptions         = null,
                                                                    IEnumerable <IGorgonPolySpriteCodec> spriteCodecs = null,
                                                                    IEnumerable <IGorgonImageCodec> imageCodecs       = null)
        {
            if (fileSystem == null)
            {
                throw new ArgumentNullException(nameof(fileSystem));
            }

            IGorgonVirtualFile file = fileSystem.GetFile(path);

            if (file == null)
            {
                throw new FileNotFoundException(string.Format(Resources.GOR2DIO_ERR_FILE_NOT_FOUND, path));
            }

            if ((imageCodecs == null) || (!imageCodecs.Any()))
            {
                // If we don't specify any codecs, then use the built in ones.
                imageCodecs = new IGorgonImageCodec[]
                {
                    new GorgonCodecPng(),
                    new GorgonCodecBmp(),
                    new GorgonCodecDds(),
                    new GorgonCodecGif(),
                    new GorgonCodecJpeg(),
                    new GorgonCodecTga(),
                };
            }
            else
            {
                // Only use codecs that can decode image data.
                imageCodecs = imageCodecs.Where(item => item.CanDecode);
            }

            if ((spriteCodecs == null) || (!spriteCodecs.Any()))
            {
                // Use all built-in codecs if we haven't asked for any.
                spriteCodecs = new IGorgonPolySpriteCodec[]
                {
                    new GorgonV3PolySpriteBinaryCodec(renderer),
                    new GorgonV3PolySpriteJsonCodec(renderer)
                };
            }
            else
            {
                // Only use codecs that can decode sprite data.
                spriteCodecs = spriteCodecs.Where(item => item.CanDecode);
            }

            Stream spriteStream = file.OpenStream();

            try
            {
                if (!spriteStream.CanSeek)
                {
                    Stream newStream = new DataStream((int)spriteStream.Length, true, true);
                    spriteStream.CopyTo(newStream);
                    newStream.Position = 0;
                    spriteStream.Dispose();
                    spriteStream = newStream;
                }

                IGorgonPolySpriteCodec spriteCodec = GetPolySpriteCodec(spriteStream, spriteCodecs);

                if (spriteCodec == null)
                {
                    throw new GorgonException(GorgonResult.CannotRead, string.Format(Resources.GOR2DIO_ERR_NO_SUITABLE_SPRITE_CODEC_FOUND, path));
                }

                // Try to locate the texture.
                string textureName = spriteCodec.GetAssociatedTextureName(spriteStream);

                GorgonTexture2DView textureForSprite = null;

                // Let's try and load the texture into memory.
                // This does this by:
                // 1. Checking to see if a texture resource with the name specified is already available in memory.
                // 2. Checking the local directory of the file to see if the texture is there.
                // 3. A file system wide search.

                // ReSharper disable once InvertIf
                if (!string.IsNullOrWhiteSpace(textureName))
                {
                    (IGorgonImageCodec codec, IGorgonVirtualFile textureFile, bool loaded) =
                        LocateTextureCodecAndFile(fileSystem, file.Directory, renderer, textureName, imageCodecs);

                    // We have not loaded the texture yet.  Do so now.
                    // ReSharper disable once InvertIf
                    if ((!loaded) && (textureFile != null) && (codec != null))
                    {
                        using (Stream textureStream = textureFile.OpenStream())
                        {
                            textureForSprite = GorgonTexture2DView.FromStream(renderer.Graphics,
                                                                              textureStream,
                                                                              codec,
                                                                              textureFile.Size,
                                                                              GetTextureOptions(textureFile.FullPath, textureOptions));
                        }
                    }
                }

                return(spriteCodec.FromStream(spriteStream, textureForSprite, (int)file.Size));
            }
            finally
            {
                spriteStream?.Dispose();
            }
        }