void AddSpawnPoints()
        {
            // Add goblin caves and set hero/boss spawn points.
            for (int y = 0; y < LevelMapSize; y++)
            {
                for (int x = 0; x < LevelMapSize; x++)
                {
                    var     location = new CGPoint(x, y);
                    DataMap spot     = levelMap.QueryLevelMap(location);

                    // Get the world space point for this level map pixel.
                    CGPoint worldPoint = ConvertLevelMapPointToWorldPoint(location);

                    if (spot.BossLocation <= 200)
                    {
                        levelBoss = new Boss(worldPoint);
                        levelBoss.AddToScene(this);
                    }
                    else if (spot.GoblinCaveLocation >= 200)
                    {
                        var cave = new Cave(worldPoint);
                        goblinCaves.Add(cave);
                        parallaxSprites.Add(cave);
                        cave.AddToScene(this);
                    }
                    else if (spot.HeroSpawnLocation >= 200)
                    {
                        DefaultSpawnCGPoint = worldPoint;                         // there's only one
                    }
                }
            }
        }