MA Ribbon R4

//@version=3

study(title="MA Ribbon R4-6 by JustUncleL", shorttitle="MA_RIBBON R4", overlay = true)

//
// Revision: R4-6
// Revision Author: JustUncleL
//
// Description:
// ============
// This indicator plots and colour codes a ribbon between two moving averages.
// The colour of the ribbon changes with trend direction: when price in uptrend
// ribbon colour is green; when price in downtrend ribbon colour is red.
//
// Options Available:
// ------------------
// 1) You can select between 11 different types of moving averages, each MA line
//    can be a different type:
//    -
// 2) Option to display coloured Candles around the Ribbon, the coulouring uses
//    the Standard candle colours:
//    - Lime    = candle closed above Ribbon.
//    - Red     = candle closed below Ribbon.
//    - Gray    = Candle Closed inside Ribbon.
//    the Grab candles scheme:
//    - Lime    = Bull candle closed above Ribbon.
//    - Green   = Bear candle closed above Ribbon.
//    - Red     = Bull candle closed below Ribbon.
//    - DarkRed = Bear candle closed below Ribbon.
//    - Aqua    = Bull candle closed inside Ribbon.
//    - Blue    = Bear candle closed inside Ribbon.
//
// 3) Option to base the candles on a higher time frame (HFT), this performed by increasing
//    the MA length to create equivalent lengths from the HFT. So no re-painting.
//    NOTE: The script will time out if the MA lengths get too long after resizing.
//
// Modifications:
// R4 - Allow achor to be used for Days and Weeks.
//    - Allow option to use standard 3-tone bar colouring, or 6-tone Grab candle Colouring
//
// R3 - Work around for transparency with drwaing bar colours.
//
// R2 - Recoded variant function with more efficient version.
//    - Change bar colouring to Grab candle style.
//    - Added named colour constants, to include fully non-transparent, work around
//      for bar colouring transparency bug.
//
// R1 - Original
//

// Use Alternate Anchor TF for MAs
anchor     = input(0,minval=0,maxval=1440,title="Use Alternate Anchor TimeFrame (0=none, max=1440 (mins,D,W)")

// Fast MA - type, length
type1   = input(defval="EMA", title="Fast MA Type: SMA, EMA, WMA, VWMA, SMMA, DEMA, TEMA, HullMA, ZEMA, TMA, SSMA ( case sensitive )", type=string)
len1    = input(defval=8, title="Fast - Length", minval=1)
// Medium MA - type, length
type2   = input(defval="EMA", title="Medium MA Type: SMA, EMA, WMA, VWMA, SMMA, DEMA, TEMA, HullMA, ZEMA, TMA, SSMA ( case sensitive )", type=string)
len2    = input(defval=21, title="Medium - Length", minval=2)
//
ma_src  = input(close,title="Source")
sBars   = input(false,title="Show Coloured Bars")
uGrabClr= input(true,title="Use Grab Bar 6-tone Colours, instead of Standard 3-tone")
// - INPUTS END

// Constants colours that include fully non-transparent option.
green100 = #008000FF
lime100  = #00FF00FF
red100   = #FF0000FF
blue100  = #0000FFFF
aqua100  = #00FFFFFF
darkred100 = #8B0000FF
gray100 = #808080FF

// - FUNCTIONS

// - variant(type, src, len)
// Returns MA input selection variant, default to SMA if blank or typo.

// SuperSmoother filter
// © 2013  John F. Ehlers
variant_supersmoother(src,len) =>
    a1 = exp(-1.414*3.14159 / len)
    b1 = 2*a1*cos(1.414*3.14159 / len)
    c2 = b1
    c3 = (-a1)*a1
    c1 = 1 - c2 - c3
    v9 = 0.0
    v9 := c1*(src + nz(src[1])) / 2 + c2*nz(v9[1]) + c3*nz(v9[2])
    v9

variant_smoothed(src,len) =>
    v5 = 0.0
    v5 := na(v5[1]) ? sma(src, len) : (v5[1] * (len - 1) + src) / len
    v5

variant_zerolagema(src,len) =>
    ema1 = ema(src, len)
    ema2 = ema(ema1, len)
    v10 = ema1+(ema1-ema2)
    v10

variant_doubleema(src,len) =>
    v2 = ema(src, len)
    v6 = 2 * v2 - ema(v2, len)
    v6

variant_tripleema(src,len) =>
    v2 = ema(src, len)
    v7 = 3 * (v2 - ema(v2, len)) + ema(ema(v2, len), len)               // Triple Exponential
    v7

// return variant, defaults to SMA
variant(type, src, len) =>
    type=="EMA"     ? ema(src,len) :
      type=="WMA"   ? wma(src,len):
      type=="VWMA"  ? vwma(src,len) :
      type=="SMMA"  ? variant_smoothed(src,len) :
      type=="DEMA"  ? variant_doubleema(src,len):
      type=="TEMA"  ? variant_tripleema(src,len):
      type=="HullMA"? wma(2 * wma(src, len / 2) - wma(src, len), round(sqrt(len))) :
      type=="SSMA"  ? variant_supersmoother(src,len) :
      type=="ZEMA"  ? variant_zerolagema(src,len) :
      type=="TMA"   ? sma(sma(src,len),len) :
                      sma(src,len)

// - /variant

// - FUNCTIONS END

// Make sure we have minimum channel spread.
Length2_    = (len2-len1)<1?len1+1:len2

// If this is 5min or less Time Frame select EMAs
mult    = anchor==0 ? 1 : interval<=0 or interval>=anchor? 1 : round(anchor/interval)>1? round(anchor/interval) : 1
Length1 = mult==1 ? len1 : (len1*mult)
Length2 = mult==1 ? Length2_ : (Length2_*mult)
//plotshape(interval,location=location.bottom)

// Get the two MAs
ma1 = variant(type1,ma_src, Length1)
ma2 = variant(type2,ma_src, Length2)

//Plot the Ribbon
ma1_=plot( ma1,color=rising(ma1,2)?green:red,style=circles,join=true,linewidth=2,transp=20,title="Fast MA")
ma2_=plot( ma2,color=rising(ma2,2)?green:red,style=circles,join=true,linewidth=2,transp=20,title="Slow MA")
fcolor = ma1>ma2?green:red
fill(ma1_,ma2_,color=fcolor,transp=80,title="Ribbon Fill")

// Colour bars according to the close position relative to the MA selected
// Or Grab candle colour code bars according to the close position relative to the MA selected
grabcol = uGrabClr? close>=open? close>ma1 and close>ma2? lime100 : close<ma1 and close<ma2? red100 : aqua100 : close>ma1 and close>ma2? green100 : close<ma1 and close<ma2? darkred100 : blue100 : na
stdcol  = uGrabClr? na : close>ma1 and close>ma2 ? lime100 : close<ma1 and close<ma2? red100 : gray100

barcolor(sBars?uGrabClr? grabcol: stdcol:na, title = "Bar Colours")

//eof