SuperMap.WindowsPhone.Mapping.TiledLayer.Draw C# (CSharp) Method

        internal override void Draw(DrawParameter drawParameter)
        {
            base.Draw(drawParameter);
            if ((base.IsInitialized && base.IsVisible) && (!Rectangle2D.IsNullOrEmpty(ViewBounds)) && (base.Container != null))
            {
                if (GetCachedResolutions() != null)
                {
                    realResolutions = this.GetCachedResolutions();
                }
                else
                {
                    realResolutions = drawParameter.Resoluitons;
                }
                double resolution = MathUtil.GetNearest(drawParameter.Resolution, realResolutions, MinVisibleResolution, MaxVisibleResolution);

                int[] span = this.GetTileSpanWithin(ViewBounds, resolution);

                int level = -1;
                needShowTiles = NeedShowTiles(resolution, span, drawParameter.UseTransitions, out level);
                TileComparer comparer = new TileComparer();
                List<Tile> needDownload = needShowTiles.Except<Tile>(_inContainer.Values, comparer).ToList();
                if (needDownload.Count > 0)
                {
                    _queueSystem.InputTiles(uniqueLayerId, needDownload);
                }
            }
        }