Metric only

Of late I’ve been leaving OSX and moving to Linux, and in the process I discovered LibrePCB. I watched lectures, got very excited, could this be a new vanguard in PCB design software ? The fact that some one had fixed the KiCad library mess. Unbelievable ! I hate KiCad, every time I use it I feel like I a need a shower, total design by committee, rivaling the USB standard . I digress.

Metric only in LibrePCB is one of those vanguard ideas. Imperial is DEAD, Rip. Can you tell me How many “twips” per inch. Should a pad be xxx twips by xxx twips. For wiggles go read the the Wiki page.

What utter insanity !

I worked for 37 years as the technical support for a behavioral analytics research lab. One of the things i learned is a basic tenet from this area of science, “DO NOT reinforce bad behavior”
E.i. “Do not feed the dog under the table”.
The use of the imperial system is that dog.
Let’s stop doing it !!

People with working brains will follow you
Here is a change to set your product ahead of the pack.

LibrePCB already defaults to metric whereever it makes sense. For example, in the standard library, metric dimensions (following IPC naming standards) are used for resistors, with the imperial variant only added in parentheses for easier lookup, e.g. “RESC2012 (0805)”.

However, a lot of our industry does use imperial units, for example for the pitch. I’m used to thining in “2.54 mm”, “1.27 mm” and “0.635 mm”, but the base reference is still tied to the inch.

I’m all for using metric whereever possible, but actively taking away imperial units from people used to them doesn’t seem like the best way to go forward.

What I’m trying to propose is that the LibrePCB it metric at it’s core, period ! No stradding the fence and make everybody warm and fuzzy. Imperial is dead. Does GM still use 7/16 wrenches? With a pure metric core the code gets simpler and lot easier to maint. The idea would be to create conversion routines to convert all imperial to metric and then pass it thru to a pure metric code base. Imperial is dying. A pure metric product would never have to go thru an awful rewrite as time progresses. The conversion routines will fall to the wayside. You’ll be left with the future !

Isn’t it already calculated internally in nanometers? That’s what is implied by the grid unit options menu. So I think you already have what you are asking for.

We need the imperial conversion readily availble for the next 20-30 years as pin spacing is almost always based on 1/10inch grid. (Which is a stupid system by either standard, true imperial would use fractions that are powers of 2.)

Until you can magically make my lifetime supply of vintage components with 1/10" pin spacing round nicely to 2.5mm I’m stuck with a 100mil grid no matter how stupid a system it is.

Absolutely, LibrePCB in its core already uses nanometers for everything. And in files, everything is in millimeters, no matter what settings you are using in the editors. Even if you configure the grid to 0.1 inches, it is stored as 2.54mm in the file, with the unit “inches” only as a hint for the GUI to know how to display the coordinates.

So, with LibrePCB, units are only a matter of GUI input/output fields. Even our Gerber export doesn’t allow to generate imperial Gerber files, while most other EDA tools support exporting imperial units :wink:

7/16 and 31/64 good bye.
Bravo !