public SymbolBitmapCache(SymbolDrawingCache symbolDrawingCache, double size)
{
m_symbolDrawingCache = symbolDrawingCache;
m_size = size;
var arr = (SymbolID[])Enum.GetValues(typeof(SymbolID));
var max = arr.Max();
m_blackBitmapList = new CacheData[(int)max + 1];
m_bitmapMap = new Dictionary<SymbolID, Dictionary<Color, CacheData>>();
}