I have following question.
In MT4 there is following function:

double iMACD(
string symbol, // symbol
int timeframe, // timeframe
int fast_ema_period, // Fast EMA period
int slow_ema_period, // Slow EMA period
int signal_period, // Signal line period
int applied_price, // applied price
int mode, // line index
int shift // shift
);

so, in my code, if I need to get macd value from current timeframe I can use following code:

double val = iMACD(NULL,0,12,26,9,PRICE_CLOSE,MODE_MAIN,0);

If indicator or strategy work at 1 minute time frame, but I want to see macd at 5 minute time frame I can use the following comand:

double val = iMACD(NULL, PERIOD_M5,12,26,9,PRICE_CLOSE,MODE_MAIN,0);

If I want to get value of previous 5 minutes time frame, I can use following code:
double val = iMACD(NULL, PERIOD_M5,12,26,9,PRICE_CLOSE,MODE_MAIN,1);
If I want to get value of 10 minutes before, I can use this line:
double val = iMACD(NULL, PERIOD_M5,12,26,9,PRICE_CLOSE,MODE_MAIN,2);

Regarding to this I have two questions:
1. How to get value of macd from time-frame different from which custom indicator is executed?
2. How to get value of macd from time-frame different from which custom indicator is executed and if time frame is not standard ( for example timeframe of 28 minutes ).
3. How to get those values while implementing IStrategy and IIndicator?

Does anybody have any idea?
P.S.
I know about the following url:
https://www.dukascopy.com/wiki/#Add_ind ... ened_chart

but it says nothing about usage of indicators during implementing IIndicator.