kicad-developers team mailing list archive

[jp charras <jp.charras@xxxxxxxxxx>]

Le 16/02/2016 09:08, Mikael Arguedas a écrit :
> Hi,
> 
> 
> 
> 
> On Mon, Feb 15, 2016 at 11:49 PM, jp charras <jp.charras@xxxxxxxxxx> wrote:
> 
>> Le 16/02/2016 07:44, Mikael Arguedas a écrit :
>>> Hi Miguel,
>>>
>>> Thanks for the clarification. I can now appreciate the difference. In
>> this
>>> case it's indeed more useful to have a minimum size that won't be 0.
>>>
>>> Actually I thought these were 1nm steps. My intent was to have every
>>> courtyard size to be rounded to 0.1mm and thus land on a 0.05mm grid as
>>> specified in the KLC.
>>> Anyway I tested it on a couple of footprints and it seems to be giving
>> the
>>> expected result.
>>>
>>> Thanks for reviewing and for the explanation!
>>
>> In fact the patch needs a bit of enhancement:
>> - It uses values given in internal units. this is not a good practice
>> if you want to use a value of 0.5 mm, use 0.5 mm. (like for all uthers
>> values)
>>
> - I did use the values already used by the scripts themselves (variables
> sizex and sizy are expressed in 1nm steps). All this patch does is rounding
> the values already used by the scripts to draw the recangle. I didnt want
> to change the internals of the script given that they all use the same
> format.
> What I can do:
>   - Use pcbnew.FromMM() method to make clearer where these numbers come
> from.
>   - Implement this ceiling function in the parent class and just call it in
> all the scripts using it.

Yes, this is a good idea.

> 
>> The meaning of values just given as integer is always not easy to
>> understand.
>> - Because the rounding is subject to change, and used 6 times, only one
>> method called 6 times is more easy to change, and more easy to
>> understand for the reader.
>> - the KLC say 0.05 mm rounding. Why to use 0.1 mm? Leave 0.05 rounding
>> level.
>>
> All the scripts seem to give the size of a rectangle to draw. This
> rectangle is centered on the origin. So if I use 0.05 for rounding the
> courtyards line may endup on a 0.025 grid. That is the reason I used 0.1mm.

In fact, AFAIK, some scripts use the size of a rectangle, and some
others the distance (coordinate) from X or Y axis.

Rectangles are used for SMD ICs, but connectors do not use always
rectangles to build the courtyard.

If you are implementing the ceiling function in a parent class, use 0.05
mm, because it will be not necessary used for sizes, but also for
distances, and round the half size if needed.

> 
>>
>> Thanks for your interest at Kicad.
>>
> You're welcome I love this project. I'm using it everyday so I'm happy to
> contribute back!
> 

-- 
Jean-Pierre CHARRAS