result = CreateUpfrontHookLayer(li,bm,x0,y0,x1,y1,flags,hook,[,bm2])
    d0                              a0 a1 d0 d1 d2 d3   d4  a3   [ a2 ]
    
struct Layer *CreateUpfrontHookLayer(
struct Layer_Info*,
struct BitMap*,
      
        
        LONG, LONG, LONG, LONG, LONG, 
struct Hook *, ... );
        
 
     
  
    Create a new Layer of position and size (x0,y0)->(x1,y1) and place it on top of all other layers. Make this layer of type found in flags Install Layer->BackFill callback hook. if SuperBitMap, use bm2 as pointer to real SuperBitMap. and copy contents of Superbitmap into display layer.
    
      - Note: 
- 
        when using SUPERBITMAP, you should also set LAYERSMART flag.