I see in one of the standard indicators they can instantiate another indicator for use in the first indicator. Ex, in Oscillator of ATR:

Average_True_Range ATR1 = new Average_True_Range(slotType);

So Oscillator of ATR can use Average True Range.

Is there a similar way I can instantiate one of my custom indicators in another?

Ex, in CustomIndicator2:

CustomIndicator1 importedCustomIndicatorInstance = new CustomIndicator1(slotType);

thanks