tile glitch.cs

            tileset.Texture = Content.Load<Texture2D>(tileset.File);
            tileset.spacing = (Math.Sqrt(64 * 64 + 48 * 48));
            double a = Math.Atan2(48, 64);
            tileset.cos = Math.Cos(a);
            tileset.sin = Math.Sin(a);

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            for (int y = 0; y < mapHeight; ++y)
            {
                for (int x = 0; x < mapWidth; ++x)
                {
                    drawX = (float)((viewOffset.X * 5 + tileset.cos * x - tileset.sin * y) * tileset.spacing);
                    drawY = (float)((viewOffset.Y * 5 + tileset.sin * x + tileset.cos * y) * tileset.spacing);

                    int index = mapIndices[x,y];
                    tile = tileset.Tiles[index];

                    spriteBatch.Draw(tileset.Texture, new Vector2(drawX + (screenWidth + tile.Width)/ 2, screenHeight / 2 - drawY - tile.Height),
                        tile, Color.White);
                }
            }