-ZvGC0wUNAI

hey traders in this lesson we are going
to be addressing one of the most uh
confusing issues in pine script which is
repainting
repainting is the boogeyman of
pinescript and tradingview scripts
it is very misunderstood by beginner
coders and to be honest in most cases
it's not that big of a deal however in
certain situations it can be misleading
at best and downright inaccurate at
worst and in this video i'm going to
break down the various types of
repainting how to avoid them and what
repainting is
so let's get started by reading the pine
script user manual section on repainting
so if i scroll down here there'll be a
link to this below the video if you want
to explore this in more detail
but trading view the staff and
developers of trading view define
repainting as a script behavior causing
historical verse real time calculations
or plots to behave differently what they
mean by differently is
that your
plots or real-time calculations will
behave differently on historical bars
versus real-time bars a classic example
of this
is in this paragraph here
the rsi is a great example
on historical bars the rsi is going to
display a value and that value will
never change because it's confirmed it's
a historical bar the bar's values are no
longer fluctuating like a real-time bar
would and so the rsi's value the
calculations the analysis that that
indicator performs is set in stone and
it is completed and will never change on
historical bars but on the current
real-time bar on your chart
that is still active and if i jump over
to trading view i can show an example of
this let me go down to the one minute
chart and throw on the rsi indicator
keep an eye on this line
you can see that it's moving around as
the current real-time bar moves around
this is one form of repainting it is
literally repainting the indicator value
for so long as this bar moves and in a
couple of seconds when this bar closes
this bar is no longer repainting but the
current new bar is and so this line will
continue to move up and down that is one
form of repainting and it is perfectly
acceptable if you know how to trade
using indicators you should know that if
you are basing your trading decisions on
indicator values or even price action
patterns you need to wait until the
candle closes or the bar closes and
confirms that value before you act on it
so if an rsi goes overbought for example
on the real-time bar and that is a
signal to inform a trading decision you
shouldn't make that trading decision
until the bar closes because there is
still a chance that it may not close as
overbought and it may move down before
the candle close same with candlestick
patterns if you're trading a candlestick
pattern like a bearish engulfing candle
is a good example
just because the bar is currently
engulfing a previous bar doesn't mean it
will look like that when the candle
closes because as you can see here the
price is moving quite rapidly and
depending on the time frame you're on
the pattern may be invalidated by the
time the candle closes so that is one
form of repainting repainting on the
current active bar is completely
acceptable as long as you understand
what it is and you understand that your
trading decisions should not be made on
the real-time bar until it closes one
hidden risk of this form of repainting
that you might not think about is when
you're creating your scripts let's say
for example you want to automate a
strategy and when a setup is detected on
your chart you want to trigger an alert
to enter a position you might write your
code and the code may look fine it might
execute perfectly fine on historical
data but on the real time bar
as soon as a setup or an indicator value
hits a certain
condition that you're looking for and
your script generates an alert
depending on how you set up your alert
in the settings menu in terms of these
options here
may cause problems so for example this
is a terrible terrible strategy in real
life but just for example purposes let's
imagine that as soon as the rsi goes
overbought you send a command to a third
party to go short on a market well if
you set your options here to
only once once per bar or once per
minute then the very moment that
the rsi goes overbought the tradingview
platform will trigger the alert and your
command will be sent off to the third
party and your
broker will enter short or your exchange
on a crypto currency market and now
you're short on a market because the rsi
went overbought and then a few minutes
later the candle closes and is no longer
overbought and suddenly you are involved
in an invalid setup an invalid trade
that you were not supposed to be in
because the rsi did not actually close
and confirm is overbought
that is one potential issue
with repainting
another issue would be candlestick
patterns like i just explained earlier
if a bar is plotting as a valid
candlestick pattern on the real-time bar
but then it closes as invalid if you
don't set up your script properly or
your alerts properly then the
alert may fire prematurely and that can
be a problem obviously because that's
how you end up involved in invalid
trades is exactly the same as entering
positions manually before the current
bar closes and then being caught in a
trade you're not supposed to be in your
scripts can do the same thing if you're
not careful now there are a couple of
ways around this the first way is to set
your alerts up so that the script only
fires the alert once per bar close the
other way to avoid this is to use the
bar states um inbuilt variable so i have
a script here that we'll get into in a
moment where we'll explore some of the
various types of repainting but if you
want to prevent your script from sending
an alert
on a real-time bar you could do
something like this let's say we have
valid short entry equals and then we
have a bunch of conditions candlestick
patterns indicator conditions and when
this is true our script enters short
what you can do is when your alert is
fired
you can do something like this
if
we have a valid short
entry
then we want to fire our alert which
sends
data to third party
the way we stop this alert from being
fired on a real sign bar is we add on
the end here if valid short entry and
bar state dot is confirmed
now this will only fire our alert on the
very final tick of a closing bar
so it will not fire any alert unless the
pattern the indicator values whatever
our script is analyzing and calculating
is confirmed on the final tick of a
closing bar
that is one way to prevent
the issues of repainting that i just
discussed and to be honest this is
probably the preferred way because that
prevents any uses of your script from
accidentally setting the alerts up
incorrectly because even if you set your
alert to once per bar or only once or
once per minute if you have this check
in your script the alert will not fire
until
this is confirmed boolean is true on the
final tick of the current real-time bar
anyway that is the most basic form of
repainting it's an acceptable form of
repainting but you do need to be aware
of it you need to be cautious of the
potential side effects that it can cause
let's get into some visual examples of
repainting
i'm going to comment out all of my plots
here except for
the first two here i'm going to save my
script so let me explain what the code
is doing here let's only focus on
let me
put in some curly
braces here and we can minimize these
bits of code and just focus
on this block of code here our atr
repainting code and if you're not aware
of what i just did here if you put in
some curly brackets in comments around
your code so we have a curly bracket
here open curly bracket and close curly
bracket you can actually click on this
little drop down arrow thing here which
will hide that block of code which is
really handy when working with complex
scripts with lots of sections but anyway
let me open up this atr repainting code
and explain what's happening here
so i have a user input here called
disable repaint and when we turn the
sinus off by default when we turn this
on our disable repaint code will be
executed instead of our real-time code
which is going to repaint so
first of all we're getting an atr value
here
and then we're just plotting
a long stop in a short trailing stop
which is the closing price
minus the atr value and the closing
price plus an atr value so if i minimize
this and we zoom in a bit let me get rid
of the rsi keep an eye on our
red and green lines notice that they are
moving with the real time bar
now the reason why these lines are
moving like this is because as the
current real-time bar moves the atr
value is changing so if i throw on the
average true range
you can see that on the real-time bar it
is going to move as price expands and
contracts now because we're on a one
minute chart and we're averaging the
past 14 bars and there's not a lot of
volatility right now this number is not
changing but if this bar was moving more
dramatically
this line would be moving our atr value
would be moving and there we go it's
starting to move now and because we're
adding the atr and subtracting it from
the current closing price our lines are
moving with the closing price and as the
atr value changes if you do not want
this behavior in your script what you
need to do is reference the previous bar
if we are calculating on a real-time bar
so if we're calculating on a historical
bar the values are confirmed and we can
calculate our trailing stop or whatever
we're doing based on that historical
bar's values but on the real time bar we
cannot do that because the values are
changing actively what we need to do is
reference the previous bar and so the
way we achieve that
is using the bar dot is confirmed
variable so here i have a
ternary condition or ternary operator
for our long stop and shortstop we're
saying is disabled repaint turned on
if so then we check is the bar state
confirmed if it is then we just subtract
the atr from the closing price or add
the atr to the closing price otherwise
if bar state is not confirmed then we
reference the previous closing price and
the previous atr value because these
values are confirmed as the previous bar
is a historical bar it's closed it's
completed so if i open up my little
settings menu here and turn on disable
repainting keep an eye on our green and
red lines they now
are referencing the previous bars closed
and adding the atr and subtracting the
atr from that value and the lines are
not moving on the current bar and just
notice that the
real time bar closed and our lines moved
now we're referencing this bar on the
current real-time bar so the script is
detecting that this bar is active
and referencing the previous bar's close
and atr value for this real time bar
that is one way to disable repainting
when we're dealing with actual visual
repainting on our chart let's have a
look at a couple of other examples let
me comment out these plots
and open up this section and i'll
minimize that
now we have signal repainting
so we just looked at the atr repainting
that's a form of indicator repainting
now let's look at the second form of
repainting which is when we are
detecting a
candlestick pattern on our chart so let
me uncomment these two plot shapes save
my code
and now our atr should go away but we're
getting
arrows drawing
on
uh higher close and lower closed candles
so whenever the current bar closes
higher than the previous high
or the current bar closes lower than the
previous low we are drawing a green and
red arrow above and below price action
so if i open up my
settings and turn off disable repainting
keep an eye on this current bar when it
exceeds the previous bars high or low
it should start drawing an arrow
even though the current bar hasn't
closed yet so i'll wait here until we
get an example
and there we go see how the arrow just
popped up and then it disappeared and
now it's back again
that is signal repainting
and if we had an alert set on this
script to send an alert or fire an alert
whenever this pattern is detected
if we didn't set up our alerts correctly
or we didn't use bar state dot is
confirmed in our code when this arrow
first popped up it would have fired an
alert so now our signal is confirmed
if i turn on disable repainting this
arrow should stay here but if i turn it
back off and this bar exceeds the
previous bars low or high we'll get an
arrow drawing onto our chart so how do
we prevent this from happening if we
don't want our signals repainting well
it's exactly the same as our indicator
repainting solution which is using bar
state dot is confirmed so here for our
long entry and short entry i'm detecting
high close and lower closed candles and
i'm checking
is the current bar confirmed
or
do we not have disable repaint turned on
so right now i've turned repaint off so
if bar state is not confirmed and we do
not have repainting turned off then our
signal is free to draw onto our chart
but if i disable repainting now
the current bar must be confirmed before
we draw
our long and short entry shapes or in
other words before long entry and short
entry can be set to true bar state must
be confirmed so that is one solution to
uh signal repainting
if you want your signals to paint on the
real-time bar but you don't want your
alerts to fire
that is where the
once per bar close alert setting comes
in handy this way you can leave your
indicator repainting
so that you get your setup drawing on
the real-time bar maybe it draws your
stops and targets that way you can get
an idea of what your setup might look
like when the candle eventually closes
you can throw on your short position
tool or long position tool calculate
your stop loss
to get a rough idea of whether or not
you can enter the trade based on how far
away your stop-loss is and your target
but you do not enter your trade you do
not execute on that signal until the bar
actually closes and is confirmed so
there are some trading
scripts some indicators i've created
that i trade on a real time bar
in intraday day trading strategies and i
leave my stops and targets drawing onto
my chart but i do not enter my order
and send my trade order until the bar
closes and is confirmed so that i know
my stops and targets are confirmed
so that is the second form of repainting
we have indicator repainting we have
candlestick pattern signal repainting
for indicator repainting that's usually
normal most indicators repaint and as
i've mentioned several times you
shouldn't act on that current repainting
value until the bar is closed same for
signal repainting when we're detecting
market conditions candlestick patterns
etc you may want your script to repaint
you may want the signal to come and go
based on what the real time bar is doing
but you should not act on it and you
should not send your alert
to any third parties or anything like
that until the bar is confirmed so keep
that in mind for those two forms of
repainting the final form of repainting
is the security function this is the
most complex form
and the most
dangerous form
in terms of misleading results in your
real-time scripts versus your historical
data
so let me save this code we'll get rid
of our signal and atr repainting code
and let's have a look at the security
function repainting so i've already
discussed this issue in previous lessons
especially the breakout strategy i
believe where we were drawing the daily
high and low onto our chart we needed to
disable repainting in that script
what you see here is let me go to a four
hour chart so
price action is a little bit closer what
you see here is repainting occurring so
right now we are getting the daily
closing price and we are adding and
subtracting the daily atr
from
that daily closing price so we're doing
exactly the same thing as our atr
repainting code but using the security
function to reference the daily chart
instead of our
current time frame and as you can see
here these lines tick up here on the
current real-time bar so if i hover my
mouse over this real-time bar keep an
eye on our values up here they are
changing uh only a little bit each time
but they are changing they are
repainting that is because the market is
currently live it's currently open and
actively trading and our daily candle
is still moving around the daily candle
close
on today's bar is not confirmed it's
real time so what we need to do in order
to fix
repainting using the security function
is the same way we fixed repainting on
this atr plot on our current time frame
we need to use the bar state dot is real
time check so there are two ways we
could do this we could say bar state dot
is confirmed question mark then
reference zero otherwise reference one
so what this code here would do
is it would check
do we have disabled repaint on
in the settings menu and
is the current bar confirmed if so that
means it's a historical bar and we are
safe to reference that historical bar's
value so we just pass in zero the
current bar otherwise if the current bar
is not confirmed then we want to
reference the previous days bar and not
the currently active bar
we want to get yesterday's closing price
and yesterday's atr value from that
higher time frame using the security
function so there are two different ways
we can do this i've got them both
written out here the first one is to
check if the bar is confirmed the second
one is to just check if the current bar
is real time as far as i know it doesn't
really matter which one you use you can
use both of these methods and they
should work the same
i tend to prefer this
version i'm not sure why i just like is
confirmed that's just my preference i
like to be consistent in my scripts and
so this is how i like to write it out
and so now if i save my code
and minimize my editor let's keep an eye
on these values here if i hover my mouse
over the current real-time bar also keep
an eye up there if i open up the
settings menu and turn on disable
repainting so that we are now checking
the bar state dot is confirmed inbuilt
condition variable even though price is
moving on the current bar our indicator
values are not moving
because we are no longer repainting we
are referencing yesterday's bar on the
real-time bar and once the daily bar
closes on this market our security
function code will reference that day's
bar and when tomorrow's trading begins
the whole process will repeat and so
it's basically the same solution for all
of these examples of repainting all you
need is this code here if i get rid of
my little settings menu condition
this is what your code needs to look
like if you want to avoid repainting on
the current real-time bar whether you
are using the security function
drawing a candlestick pattern
referencing an indicator value
if you do not want your indicator to
repaint or update on a real-time bar
this is how you need to write your code
out in order to prevent your script from
updating on the current real-time bar
and repainting so those are the main
three examples of visual repainting on
your charts
the final thing i want to draw your
attention to
is when using the security function or
any of the request
namespace functions so any of these
inbuilt functions here there is the
issue
of referencing candlestick data that you
should not have access to yet
so what what i mean by that is if you
set
the setting look ahead
to bar merge dot look ahead
on if i throw that onto my security
functions and save my code and let's
change
some of this code let me get rid of the
atr and long stop short stop let's
change this to just reference the higher
time frame close let me plot that onto
the chart as green and save my code so
now we're drawing the previous day's
closing price over today's price action
if i go out to the daily chart and let's
have a look at
uh let's have a look at this big red bar
right here let me put a vertical line on
there and let me draw
a line across the closing price value so
the close of this bar was
dot 49241.12
two four one dot twelve uh let me bring
it to the front and let's drop down to a
one hour time frame and zoom out
so here we are this blue line indicates
the beginning of that big red day and
you can see that we have this big
sell-off here big wick to the downside
that is
this wick here
so if we drop down to that one hour time
frame and we look at our white line that
is marking the closing price of that
daily bar
if i delete that white line have a look
at our green line here
this green line is drawing across the
exact same value
as our white line this is where that big
red day closed but notice that it is
drawing over price action
from the very start of that intraday
session
so this blue line marks the start of
that big red day and our green line is
drawing the closing price of that big
red day
but it's drawing it over
price action that occurred during that
day
or in other words we are cheating we are
looking ahead to the close of of this
day before it was actually known to us
that's because i've set look ahead to on
bar merge dot look ahead on by default
this is normally off so you don't
normally need to worry about this but if
you're ever dealing with a script that
has look ahead turned on beware of this
issue
so for example if you have a strategy
that exits a trade takes profit for
example at a previous day's high or low
and you have look ahead turned on then
your script is going to have insanely
profitable results because it's actually
cheating it knows where the current
day's high is going to be before that
bar had actually closed if i set look
ahead back to off
this
uh green line here we'll move to the
next day
which is the day after this big red bar
so on this day here we will draw this
red bars close across this day's price
action intraday price action which is
how it should be so now if i turn look
ahead back off and save my script watch
this green line it's now moved to this
day and now on this big red day we are
referencing the previous day's close
over that red days intraday price action
or in other words we are not cheating
anymore we are not accessing data that
we shouldn't have access to until after
that trading session had closed or that
bar had closed many traders on trading
view also refer to what i just showed
you as repainting technically it's not
repainting it's just a look ahead bias
it's kind of cheating
but for whatever reason the trading view
community does sometimes refer to this
functionality of a script as repainting
and it's obviously a huge problem
because it can lead to unrealistic
results in your strategy scripts if you
were using security data with lookahead
turned on so my advice would be to never
turn look ahead on unless you have a
very very specific reason to i can't
think of any off the top of my head but
there are some use cases for wanting
lookahead on
otherwise it wouldn't be a feature in
the first place
but your default stance in your coding
should be to always leave this as off
which it is by default so if you don't
specify this at all the script will
assume that you do not want to cheat in
your security function and you only want
to reference data that makes sense that
you should have access to after that
data has been confirmed by the bar
closing so now we're drawing this
previous days bar close over that big
red bar by drop out to the daily chart
and we have a quick look
you can see that my white line is a
little bit wonky but it's right at that
previous bars closed we're drawing that
white line over this big red day that is
fine that's perfectly fine because on
this big red day we would obviously have
access to the previous day's close
what we don't have access to
is this big red day's close until
this bar
so that's a crash course in repainting
how to avoid it
why it can be dangerous and why
sometimes it's not dangerous at all like
without indicator repainting sometimes
you want
the rsi to update in real time other
times you may not want this to happen or
at least you may not want your script to
act on this value until
after this value is confirmed the way
you do that is using our bar state dot
is confirmed check along with whatever
candlestick pattern you're detecting
whatever indicator value you are
interacting with
or whatever security function
expression you are passing in whatever
data you're trying to get from your
higher time frame or your other market
anyway that will do it for today's
lesson i'll leave the source code to
this example script below so that you
can have a look through it
study it and get very familiar with
repainting how to avoid it it's very
important that you understand
when this happens in your scripts when
it can be a problem and how to eliminate
it when you don't want it to be a
behavior of your script i hope you found
this lesson interesting it's a slightly
edited lesson straight out of my
pinescript mastery course if you want to
learn more about pinescript and some of
the more advanced features of pinescript
and have someone guide you through
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on this subject material good luck with
your trading good luck with your coding
and i'll speak with you in the next
video
you