//+------------------------------------------------------------------+
//|Based on NonLagDOT.mq4 by TrendLaboratory                         |
//|http://finance.groups.yahoo.com/group/TrendLaboratory             |
//|igorad2003@yahoo.co.uk                                            |
//|                                                         Dots.mq4 |
//|                                  Copyright © 2011, EarnForex.com |
//|                                         http://www.earnforex.com |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2011, www.EarnForex.com"
#property link      "http://www.earnforex.com/"

/*
   Uses price curve angle calculations to come up with simple price indication.
   Simple strategy: enter when 2 dots of same color appear; exit, when different color dot appears.
*/

#property indicator_chart_window
#property indicator_buffers 2
#property indicator_color1 RoyalBlue
#property indicator_width1 2
#property indicator_color2 Red
#property indicator_width2 2

//---- input parameters
extern int    Length       = 10;
extern int    AppliedPrice = 0;
extern int    Filter       = 0;
extern double Deviation    = 0;
extern int    Shift        = 0;

//---- indicator buffers
double UpBuffer[];
double DnBuffer[];

//---- global variables
double Cycle = 4;

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
{
   IndicatorBuffers(2);
   
   SetIndexStyle(0, DRAW_ARROW);
   SetIndexBuffer(0, UpBuffer);
   SetIndexStyle(1, DRAW_ARROW);
   SetIndexBuffer(1, DnBuffer);
   
   SetIndexEmptyValue(0, EMPTY_VALUE);
   SetIndexEmptyValue(1, EMPTY_VALUE);

   SetIndexArrow(0, 159);
   SetIndexArrow(1, 159);

   SetIndexLabel(0, "Up");
   SetIndexLabel(1, "Dn");

   SetIndexShift(0, Shift);
   SetIndexShift(1, Shift);
   
   SetIndexDrawBegin(0, Length * Cycle + Length);
   SetIndexDrawBegin(1, Length * Cycle + Length);

   IndicatorShortName("Dots("+Length+")");
   IndicatorDigits(MarketInfo(Symbol(), MODE_DIGITS));

   return(0);
}

//+------------------------------------------------------------------+
//| Dots                                                             |
//+------------------------------------------------------------------+
int start()
{
   int    i, shift, counted_bars = IndicatorCounted(), limit, trend = 0;
   double alfa, beta, t, Sum, Weight, g, price, MABuffer_prev = 0, MABuffer = 0;
   double pi = 3.1415926535;    

   double Coeff = 3 * pi;
   double Phase = Length - 1;
   int Len = Length * Cycle + Phase;
   
   if (counted_bars < 0) return(0);
   if (counted_bars > 0) limit = Bars - counted_bars;
   else limit = Bars - Len - 1; 
   
   for (shift = limit; shift >= 0; shift--) 
   {	
      Weight = 0; Sum = 0; t = 0;
       
      for (i = 0; i <= Len - 1; i++)
	   {
         g = 1.0 / (Coeff * t + 1);   
         if (t <= 0.5 ) g = 1;
         beta = MathCos(pi * t);
         alfa = g * beta;
         price = iMA(NULL, 0, 1, 0, MODE_SMA, AppliedPrice, shift + i); 
         Sum += alfa * price;
         Weight += alfa;
         if (t < 1) t += 1.0 / (Phase - 1); 
         else if (t < Len - 1) t += (2 * Cycle - 1) / (Cycle * Length - 1);
      }
      
      MABuffer_prev = MABuffer;
      if (Weight > 0) MABuffer = (1.0 + Deviation / 100) * Sum / Weight;
   
      if (Filter > 0)
         if (MathAbs(MABuffer - MABuffer_prev) < Filter * Point) MABuffer = MABuffer_prev;
      
      if (MABuffer - MABuffer_prev > Filter * Point) trend = 1; 
      else if (MABuffer_prev - MABuffer > Filter * Point) trend = -1; 

      if (trend > 0) UpBuffer[shift] = MABuffer;
      else if (trend < 0) DnBuffer[shift] = MABuffer;
   }

	return(0);	
}