Fast - MACD

/*
 * Watts MACD: the MACD indicator as shwon in Watts scalping system.
 * However, I added a style input choice. Style 0 will plot MACD histograms
 * in two different colors based on if the histogram bar is > or < 0. The 
 * style choice of 1 will plot MACD histograms in two different colors based
 * on if current histogram bar is > or < than previous histogram bar. 
 * Style 0 is the original style of Watts system.
 * 
 * Use it at your own risk.
 *
 * Author: Peter Chen
 *
 * History: 
 *    6/13/2008: First Verision.
 */


//---- indicator settings
#property  indicator_separate_window

//Buffers needed to draw indicators
#property  indicator_buffers 5 
//Histograms
#property  indicator_color1  Gray
#property  indicator_color2  Lime
#property  indicator_color3  Red
//MA lines on histograms
#property  indicator_color4  Lime
#property  indicator_color5  DeepPink

#property  indicator_width1  1
#property  indicator_width2  1
#property  indicator_width3  1
#property  indicator_width4  2
#property  indicator_width5  2

//---- indicator parameters
extern int FastEMA = 34;
extern int SlowEMA = 89;
extern int SignalEMA = 13;
extern int HistoSMA1 = 1;
extern int HistoSMA5 = 5;
extern int Style = 1; //0 or 1
//---- indicator buffers
double     HistoBuffer[];
double     MacdBuffer[];
double     SignalBuffer[];
//These are used for painting
double     MA1Buffer[];
double     MA5Buffer[];
double     ExtBuffer0[];
double     HistoUpBuffer[];
double     HistoDnBuffer[];


//+------------------------------------------------------------------+
//| Custom indicator initialization function                         |
//+------------------------------------------------------------------+
int init()
  {
   //3 additional buffers are used for a total of 8 buffers
   IndicatorBuffers(8);
//---- drawing settings
   SetIndexStyle(0,DRAW_HISTOGRAM);
   SetIndexStyle(1,DRAW_HISTOGRAM);
   SetIndexStyle(2,DRAW_HISTOGRAM);
   SetIndexStyle(3,DRAW_LINE);
   SetIndexStyle(4,DRAW_LINE);
   
   SetIndexDrawBegin(0,SlowEMA);
   SetIndexDrawBegin(1,SlowEMA);
   SetIndexDrawBegin(2,SlowEMA);
   SetIndexDrawBegin(3,SlowEMA);
   SetIndexDrawBegin(4,SlowEMA);
   
   IndicatorDigits(Digits+2);

   SetIndexBuffer(0,ExtBuffer0);
   SetIndexBuffer(1,HistoUpBuffer);
   SetIndexBuffer(2,HistoDnBuffer);
   SetIndexBuffer(3,MA1Buffer);
   SetIndexBuffer(4,MA5Buffer);
   SetIndexBuffer(5,HistoBuffer);
   SetIndexBuffer(6,MacdBuffer);
   SetIndexBuffer(7,SignalBuffer);
   
   
//---- name for DataWindow and indicator subwindow label
   IndicatorShortName("Watts_MACD("+FastEMA+","+SlowEMA+","+SignalEMA+")");
//---- initialization done
   return(0);
  }
//+------------------------------------------------------------------+
//| Moving Average of Oscillator                                     |
//+------------------------------------------------------------------+
int start()
  {
   int limit;
   double current = 0;
   double prev = 0;
   
   int counted_bars=IndicatorCounted();

   if(counted_bars>0) counted_bars--;
   limit=Bars-counted_bars;

   for(int i=0; i<limit; i++)
      MacdBuffer[i]=iMA(NULL,0,FastEMA,0,MODE_EMA,PRICE_CLOSE,i)-iMA(NULL,0,SlowEMA,0,MODE_EMA,PRICE_CLOSE,i);
   
   for(i=0; i<limit; i++)
      SignalBuffer[i]=iMAOnArray(MacdBuffer,Bars,SignalEMA,0,MODE_EMA,i);

   for(i=0; i<limit; i++) 
      HistoBuffer[i]=MacdBuffer[i]-SignalBuffer[i];
      
   for(i=0; i<limit; i++) {
      MA1Buffer[i]=iMAOnArray(HistoBuffer,Bars,HistoSMA1,0,MODE_SMA,i);
   }
   
   for(i=0; i<limit; i++) {
      MA5Buffer[i]=iMAOnArray(HistoBuffer,Bars,HistoSMA5,0,MODE_SMA,i);
   }
      
      
   //Paint the bars
   for (i = 0; i < limit; i++) { 
       current = HistoBuffer[i];
       prev = HistoBuffer[i+1];
       
       if (Style == 0) {
         if (current > 0) {
           HistoUpBuffer[i] = current; 
           HistoDnBuffer[i] = 0.0;
           ExtBuffer0[i] = 0.0;
         } else if (current < 0) {
           HistoUpBuffer[i] = 0.0;
           HistoDnBuffer[i] = current;
           ExtBuffer0[i] = 0.0;   
         } else {
           HistoUpBuffer[i] = 0.0;
           HistoDnBuffer[i] = 0.0;
           ExtBuffer0[i] = current;  
         }
       
       } else  { //Assume 1
         if (current > prev) { 
           HistoUpBuffer[i] = current; 
           HistoDnBuffer[i] = 0.0;
           ExtBuffer0[i] = 0.0;
         } else if (current < prev) {
           HistoUpBuffer[i] = 0.0;
           HistoDnBuffer[i] = current;
           ExtBuffer0[i] = 0.0;
         } else {
           HistoUpBuffer[i] = 0.0;
           HistoDnBuffer[i] = 0.0;
           ExtBuffer0[i] = current;
         }
       }
   
   }
//---- done
   return(0);
  }
//+------------------------------------------------------------------+