Hi
I have been playing around with this a bit, but I do not have a definite answer. There must be a way though, using b_tick and l_tick.
Here is what I tried:
r_ticks(back_price,1/b_tick)
the idea being you work out how many ticks for one full point
and then use r_ticks for that amount of ticks
the problem, as you say, comes when the calculation spans across a tick increment change.
For prices in the range 2.02 to 30.00 you can just add or subtract the number:
back_price +1
lay_price - 1
etc.
or you can set a constant
back_price + [constant]
etc.
...but you will need to round the result to the next tick increment
If you actually want the prices as whole numbers:
INTEGER(back_price+1)
etc.
Outside of the range 2.02 to 30.00 you will get invalid tick increments above 30.00 and 2.00 or below will equal 0, unless you adjust you calculation accordingly.
Sorry I can't be more helpful. This probably just confirms what you have said already.