kicad-developers team mailing list archive

[Dick Hollenbeck <dick@...>]

Lorenzo wrote:
> --- In kicad-devel@xxxxxxxxxxxxxxx, Dick Hollenbeck <dick@...> wrote:
>
>
> > pad was exactly defining one of the grid cells points. Then I can 
> > establish the cell granularity to be some multiple of that pitch.
> >
> > I hope this helps clarify my problem and a potential solution. Just 
> > having metric without this grid offset may not end up being that helpful. 
>
> I had the same problem defining some non-symmetric package (an infrared gas cell, BTW), which had two cluster of pins. The difference is that a module origin can be relocated at anytime, the board origin cannot.
>
>
> > Or did I miss a capability that is already in Kicad?
>
> I think that for now it can't be done.
>
> Quick idea: what about grid points calculated around the auxiliary axis? the main origin (the global coordinates) is almost insignificant anyway (it means paper space!). As a side effect that would align the grid relative to the board (in the usual case of the aux origin on a border corner).
>
> For your BGA you could just move the origin to your module center (it's quick, there a dedicated toolbar button right for that... and now it's usually used about ONCE per board:D that's a waste) so that the whole grid would be aligned to your pins.
>
> IIRC the now the only use of the aux axis is for plotting/drilling... it could be exploited for more useful things (just remember to put it at home before exporting for fabrication).
>
> Extra-bonus function for brownie points: snap the origin on a mire when clicked on it (for local fiducials or frequently needed origins :D)

Lorenzo, this is another good idea, but I would like it even better if 
we could simply add another origin, the grid origin (or offset). I 
don't like moving my aux origin because it can be time consuming to set 
it, and I don't want to have to remember to do that before generating 
gerbers. My aux origin is tricky, to set, honestly. That is because my 
boards are odd sizes, and the board houses like the gerber origin in the 
lower left, whereas my board origin is in the upper left. I do not want 
to have to set it more than once, thanks very much.


So lets combine the two ideas: we borrow the code which sets the aux 
origin, and simply use it to set the grid origin. Then one has to 
remember that the grid origin is not going to change the coordinate 
system in any way. It is simply an offset from the true origin, to a 
point which is known to be on the grid. I'm thinking the UI code is 
95% the same. It is simply a matter of grabbing that grid offset and 
saving it, and using it in the snap calculations.


Dick