2 new units schemes for the construction area

[yorik]

I added 2 new units schemes that can be handy for who works with buildings, architects, civil engineers, etc:
- Building Euro: prints lengths in centimeters, areas in square meters and volumes in cubic meters.
- Building US: prints lengths in the form: 3' - 4 1/4" , areas in square feet and volumes in cubic feet.

[jmaustpc]

Hi Yorik
that will be useful for all those that it effects!

- Building US: prints lengths in the form: 3' - 4 1/4" , areas in square feet and volumes in cubic feet.

I think I found a bug in the US one though. Of course apart from the obvious bug in that it uses those stupid units! I started FreeCAD with default "start WB, switched to Part WB, created a new document, inserted a default Part Cube, edit its Length Width Height parameters to 1099 1880 and 1667 or something like that, all in the default metric schema, then switched to "Building US" which changed all the values to display as you said. Firstly it seems you must be rounding to the nearest 1/4 inch? If so this may be intentional. However I thought I noticed the cube change size, not certain if it did, but then each time I just clicked on a parameter in property editor, I got a different smaller value and the cube changed size again. This happened several times per parameter, I think it was 3 times each, until the values became 1", 2" and 1". Sounds like something is changing in the property itself rather than just the display unit of the value.

Are you rounding to the nearest 1/4"? If so, does it change the value its self or is it supposed to just round the value displayed? Obviously the constantly changing value is unintentional. Unless of course you are just trying to annoy Yanks!

Jim


OS: Ubuntu 12.04.5 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.7682 (Git)
Build type: Debug
Branch: master
Hash: 3d95239bae1a9cf4b961ba45bf14553be91002f9
Python version: 2.7.3
Qt version: 4.8.2
Coin version: 3.1.3
OCC version: 6.9.1.oce-0.18-dev

[yorik]

Currently it is rounding everything to 1/8 of inch. I couldn't find any "official" norm that gives the appropriate denominator, I already saw measures in
1/16 of inch, but it seems very uncommon in the building industry.

Of course people working with smaller objects commonly use 1/16 or even 1/32. One next step would be to add a pref option to the Units dialog to specify the max denominator you want.

Note that this unit scheme only outputs a representation string. It doesn't affect the real measurement of an object. So far, however, the expression parser cannot take things like 3' - 5 1/2". So If you try inputting values like that, you'll likely get something else. So far (I think) what works for input is 3' 5.5" or 41.5"

[jmaustpc]

Note that this unit scheme only outputs a representation string. It doesn't affect the real measurement of an object. So far, however, the expression parser cannot take things like 3' - 5 1/2". So If you try inputting values like that, you'll likely get something else. So far (I think) what works for input is 3' 5.5" or 41.5"

That probably explains what I was seeing then, because each time I simply clicked on then off the value in property editor, it would have passed the value through expressions, hence scrambling my cube. Do you think it might perhaps be best to remove the imperial fractions until if/when expressions ever supports it?

Regarding the rounding, perhaps for buildings you are correct, it sounds about right, we used to use 1/128th a lot in manufacturing, for example in drill sizes etc. I think smaller than that would have been in "thou" for things like fit clearance. We still occasionally came across imperial legacy stuff in the late 1980s but by the late 1990s it was almost completely gone. So mostly I am trying to remember things that my father might have said when I was a child. Australia switched to metric before I started school so my knowledge has gaps!

[yorik]

Do you think it might perhaps be best to remove the imperial fractions until if/when expressions ever supports it?

Well... we're in development version I think if we remove it, we'll forget to adapt the expression engine...

[wandererfan]

Currently it is rounding everything to 1/8 of inch. I couldn't find any "official" norm that gives the appropriate denominator, I already saw measures in 1/16 of inch, but it seems very uncommon in the building industry.

Carpenters frequently measure to the 1/16th. Then they cut with a 1/8" kerf blade in a handheld saw. So 1/16th should be good enough for ImperialBuilding.

Anybody that wanted to use 1/32, 1/64, 1/128 etc would have to use ImperialHistoricalEngineering or ImperialModelMaking!

wf

[rjpeek]

I'm very happy to see US fractions being displayed while I'm working on a sketch. I'm working on a small scale model and would like to rounding everything to 1/64 of inch. I'm working on the right side of my small scale model and then will mirror it to create the left side using the mirroring tool under the Part Workbench. If I click on Pad (Mirror #1) it shows the mirrored dimension in mm, I would like to see it displayed in fractions too.

[bejant]

I added 2 new units schemes that can be handy for who works with buildings, architects, civil engineers, etc:
- Building Euro: prints lengths in centimeters, areas in square meters and volumes in cubic meters.
- Building US: prints lengths in the form: 3' - 4 1/4" , areas in square feet and volumes in cubic feet.

Thanks Yorik - it will be very helpful!

[jmaustpc]

Do you think it might perhaps be best to remove the imperial fractions until if/when expressions ever supports it?

Well... we're in development version I think if we remove it, we'll forget to adapt the expression engine...

Hi Yorik, but is it even possible? Could expressions be made to distinguish between 3-1/2 being 3" and a half or being 3 minus 1 divided by 2?

I understand what you are saying about it being dev branch, but all you have to do is click on a property then click off that property and the solid's size changes, that's to me a pretty serious bug. Fractions are not important core functionality, we have had one user ask for it, at best it could only be described as a small old fashioned niche use case, maybe I am wrong but really how many people/industries would seriously want to work in fractions? But which ever is the case with fraction use, I don't think its in anyway worth including if we get such a horrible bug (making fractions unusable anyway) in master. I would have thought this could corrupt PartDesign models due to topological naming, by just high lighting a property, if so its to dangerous to leave in master. Others would have to test this to see if my concerns are justified or not.

I would like to say thanks for the other schema. I wonder if it might be better to name them something like "building_cm" rather than "Building European" etc. as it might perhaps be more clear. Also if you don't do it first, I was thinking of adding some more along the same lines as yours. I was thinking of adding "Building_mm" for example. Also some of the others have been talking about "civil engineering" where I wonder if KM/hectares might or might not, be useful.

Jim

[yorik]

Hi Yorik, but is it even possible? Could expressions be made to distinguish between 3-1/2 being 3" and a half or being 3 minus 1 divided by 2?

Hm you have a point there....

I understand what you are saying about it being dev branch, but all you have to do is click on a property then click off that property and the solid's size changes, that's to me a pretty serious bug.

Of course, and maybe caused by the problem above. I'll experiment removing the "-"

Aren't you exagerating a bit, otherwise? I know it's annoying that it doesn't work fully yet, but it's optional, nobody is forced to use that schema, so I don't think it's "horrible" or "dangerous"... Besides, I plan to fix it sooner or later...