//+------------------------------------------------------------------+
//|                                 Percentage Crossover Channel.mq4 |
//|                                        Copyright © 2009, Vic2008 |
//|                                                                  |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2009, Vic2008"
#property link      ""

#property indicator_chart_window
#property indicator_buffers 3
#property indicator_color1 Red
#property indicator_color2 Red
#property indicator_color3 Red

extern double percent=1.0;
extern bool channel=True;

//---- buffers
double ExtMapBuffer1[];
double ExtMapBuffer2[];
double ExtMapBuffer3[];

double PREV=0;

//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
//---- indicators
   SetIndexStyle(0,DRAW_LINE);
   SetIndexBuffer(0,ExtMapBuffer1);
   SetIndexStyle(1,DRAW_LINE);
   SetIndexBuffer(1,ExtMapBuffer2);
   SetIndexStyle(2,DRAW_LINE);
   SetIndexBuffer(2,ExtMapBuffer3);
   
   PREV=0; //Close[0];
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator deinitialization function                       |
//+------------------------------------------------------------------+
int deinit()
  {
//----
   
//----
   return(0);
  }
//+------------------------------------------------------------------+
//| Custom indicator iteration function                              |
//+------------------------------------------------------------------+
int start()
  {
   int    counted_bars=IndicatorCounted();
   int i;
   double var1;
   
   int t=Bars-counted_bars;
   if (t>1){  t=Bars-3;  }
   
//----

 var1=percent/100;

for( i=t; i>=0; i-- ){

   if( (Close[i]*(1-var1)) > PREV ){ ExtMapBuffer1[i]=Close[i]*(1-var1); }
   else{ 
         if( (Close[i]*(1+var1)) < PREV ){ ExtMapBuffer1[i]=Close[i]*(1+var1); }
         else{  ExtMapBuffer1[i]=PREV; }
       }
   PREV=ExtMapBuffer1[i];
  
   if( channel==True ){ 
      ExtMapBuffer2[i]=ExtMapBuffer1[i] + (ExtMapBuffer1[i]/100) * percent;
      ExtMapBuffer3[i]=ExtMapBuffer1[i] - (ExtMapBuffer1[i]/100) * percent;
   }
}   
   
   return(0);
  }
//+------------------------------------------------------------------+