//+------------------------------------------------------------------+
//|                                                    AO (AM)       | 
//+------------------------------------------------------------------+
#property  copyright "Andrey Matvievskiy"
#property  link      ""
//---- indicator settings
#property  indicator_separate_window
#property  indicator_buffers 3
#property  indicator_color1  Black
#property  indicator_color2  Green
#property  indicator_color3  Red

extern int PeriodMA1 = 34;
extern int PeriodMA2 = 5;
extern int TypeMA1 = 0;
extern int TypeMA2 = 0;
extern int PriceMA1 = 4;
extern int PriceMA2 = 4;
extern int TF1 = 0;
extern int TF2 = 0;
extern int Shift1 = 0;
extern int Shift2 = 0;
//---- indicator buffers
double     ExtBuffer0[];
double     ExtBuffer1[];
double     ExtBuffer2[];

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
   //---- drawing settings
   SetIndexStyle(0,DRAW_NONE);
   SetIndexStyle(1,DRAW_HISTOGRAM);
   SetIndexStyle(2,DRAW_HISTOGRAM);
   IndicatorDigits(Digits+1);
   SetIndexDrawBegin(0,34);
   SetIndexDrawBegin(1,34);
   SetIndexDrawBegin(2,34);
//---- 3 indicator buffers mapping
   SetIndexBuffer(0,ExtBuffer0);
   SetIndexBuffer(1,ExtBuffer1);
   SetIndexBuffer(2,ExtBuffer2);
//---- name for DataWindow and indicator subwindow label
   IndicatorShortName("AO (AM)");
   SetIndexLabel(1,NULL);
   SetIndexLabel(2,NULL);
//---- initialization done
   return(0);
  }
//+------------------------------------------------------------------+
//|                                      |
//+------------------------------------------------------------------+
int start()
  {
   int    limit;
   int    counted_bars=IndicatorCounted();
   double prev,current;
//---- last counted bar will be recounted
   if(counted_bars>0) counted_bars--;
   limit=Bars-counted_bars;
//---- macd
   for(int i=0; i<limit; i++)
      ExtBuffer0[i]=iMA(NULL,TF2,PeriodMA2,Shift2,TypeMA2,PriceMA2,i)-iMA(NULL,TF1,PeriodMA1,Shift1,TypeMA1,PriceMA1,i);
//---- dispatch values between 2 buffers
   bool up=true;
   for(i=limit-1; i>=0; i--)
     {
      current=ExtBuffer0[i];
      prev=ExtBuffer0[i+1];
      if(current>prev) up=true;
      if(current<prev) up=false;
      if(!up)
        {
         ExtBuffer2[i]=current;
         ExtBuffer1[i]=0.0;
        }
      else
        {
         ExtBuffer1[i]=current;
         ExtBuffer2[i]=0.0;
        }
     }
//---- done
   return(0);
  }
//+------------------------------------------------------------------+