The point is: you're changing the ObjectGrid2D dimensions but you're not changing these hard-coded constants on which you do your loops.

> On Jan 26, 2018, at 1:59 PM, Stewart Aitken <[log in to unmask]> wrote:
>
> Hi Sean,
>
> These are coded so I can use them later for calculations.
>
> I suppose I could get them from SimEnviron and thus only declare them once in the control class.
>
> Kind regards,
>
> Stewart