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Re: Metric and English grids sizes.
Mon, 12 Oct 2009 17:47:18 -0000
--- In kicad-devel@xxxxxxxxxxxxxxx, jean-pierre charras - INPG <jean-
> Unfortunately, grid size cannot be handled in decimils.
> In pcbnew grid is handled as double.
> This is because for many grids values in mm, using a value rounded in
> decimils creates a cummulative error that can be important
> (some mm for a 300 mm board)
Right, didn't thing about that.
> So grid sizes must be given
> - always in inches or decimils but using a floating point value, for non
> integer values as needed for metric grids
> - or as an integer in decimils or um units and give the used unit (um ou
> decimil) as parameter
Both are reasonable solutions, the second one could help in proposing the right measure unit when changing grid. At the end they are fully equivalent IMHO
Do whatever is easier to implement (probably #1 in decimils)