//+------------------------------------------------------------------+
//|                                  MaChannel.mq4   |
//| 2 mas, one widthFactor above High, one widthFactor below Low |     
//|  line buffers show:  ma type & price |
//|  extra buffers show:  channel width, slopes        |
//+------------------------------------------------------------------+

#property  indicator_chart_window
#property  indicator_buffers 4
#property indicator_color1 Black
#property indicator_color2 SkyBlue
#property indicator_color3 SkyBlue

extern int MAPeriod =	7 ;
extern string type = "--- Type: 0=sma, 1=ema, 2=smma, 3=lwma " ;
extern int MAType =	1; 
extern string price = "--- Price: 0=c, 1=o, 2=h, 3=l, 4=(h+l)/2, 5=(h+l+c)/3, 6=(h+l+c+c)/4 " ;
// extern int MAPrice = 	4; 
extern int PriceHi = 	2; 
extern int PriceLo = 	3; 
// extern string width = "--- Channel width " ;
extern double widthFactor = 	0.6 ; 

double Width, AvgWidth;
double WidthBuffer[], BufferHi[], BufferLo[], SlopesBuffer[] ;

int init()
  {
   IndicatorBuffers(4);
   string widthFac = DoubleToStr(widthFactor,2) ;
   IndicatorShortName( "MaChannel " +MAPeriod + " - " +widthFac );
   IndicatorDigits(MarketInfo(Symbol(),MODE_DIGITS));

   SetIndexBuffer(0,WidthBuffer); //			chan width 
   SetIndexStyle(0,DRAW_NONE);
   SetIndexLabel(0,"MaChannel " +MAPeriod +" h-l"); 

   SetIndexBuffer(1,BufferHi); //				hi line 
   SetIndexStyle(1,DRAW_LINE,STYLE_SOLID,1);
   SetIndexLabel(1," ma " +MAPeriod + " " + MAType + " " +PriceHi + " + " +widthFac );
   SetIndexDrawBegin(1,MAPeriod);

   SetIndexBuffer(2,BufferLo); //				lo line 
   SetIndexStyle(2,DRAW_LINE,STYLE_SOLID,1);
   SetIndexLabel(2," ma " +MAPeriod + " " + MAType + " " +PriceLo + " - " +widthFac );
   SetIndexDrawBegin(2,MAPeriod);

   SetIndexBuffer(3,SlopesBuffer); //			slopes 
   SetIndexStyle(3,DRAW_NONE);
   SetIndexLabel(3," slopes");

   return(0);
  }

int start()
 {
   int limit, counter; 
   double MaHigh, MaLow, MaWidth ; 
   int counted_bars = IndicatorCounted();
   //---- check for possible errors
   if (counted_bars<0) return(-1);
   //---- last counted bar will be recounted
   if (counted_bars>0) counted_bars--;
   limit = Bars - counted_bars;

   for(int i=limit; i>=0; i--)
   {
        counter=i;
        Width=0;
        AvgWidth=0;
        for (counter=i; counter<=i+9;counter++)
        {
           AvgWidth=AvgWidth+MathAbs(High[counter]-Low[counter]);
        }
        Width=AvgWidth/10 ;
        MaHigh = iMA(NULL,0,MAPeriod,0,MAType, PriceHi,i);
        MaLow = iMA(NULL,0,MAPeriod,0,MAType, PriceLo,i);
        MaWidth = MaHigh - MaLow ; 
        WidthBuffer[i] = MaWidth ; 
        BufferHi[i] = MaHigh + Width * widthFactor ; 
        BufferLo[i] = MaLow - Width * widthFactor ; 
        SlopesBuffer[i] = (BufferHi[i] - BufferHi[i+1]) + ( BufferLo[i] - BufferLo[i+1] ) ;
   }
 
      return(0);
  } // start()