UNITS are confusing...!


#1

hello guys…!
Can some one explain me what unit shoul I expect from dynamo geometry its really confusing
i have an element geometry and volume extracted from it should it follow Revit units? or imperial?
or dynamo has some special units?

The first time I noticed the output in cu.ft so created a coustom node to change cu.ft to project units
but as I change the units to mm3 to check it its returns in m3 ,No idea whats happening plz help me out with the answer to “What units does the nodes involving geometry follow?”


#2

Just in the same graph with different elements,
units are set to m3 and the node gives values in mm3.


#3

Have a look here:
https://www.revitforum.org/dynamo-bim/34248-dynamo-export-unit-conversion-query.html

Apparently @Sol_Amour dabbles in forums outside of this one…


#4

Hi @JacobSmall, I couldn’t really relate this to the post as they have a parameter and trying to get units from it ,whereas here Its a geometry and I am confused on how to extract units information from geometry.
Also, I understand that geometry is unit less but still it has to have a unit when expressed as volume right?
Maybe I didn’t get the catch,It would be great if you brief a bit about it .


#5

Whats the unit conversion between the sheet bounding box and the view ports? What do would I scale the view port rectangles down to, to fit into the sheet rectangle? Am I missing something super simple? :sweat_smile:


#6

Viewports are a area around your virtual building/element that are scaled accordingly to the view scaling, so these should equal that area from this space not the scaled version.

This is because they are physically there in the 3d space, where as a title block is not in this same space so is the area directly given.


#7

Hi @Brendan_Cassidy
The problem here is in both the graphs (in solid .volume and width ,height ect of viewport) dynamo tries to give you a number What is the unit of the number its giving you? and what decide the unit of these numbers?


#8

I have almost a thousand posts on that forum and all of them are about Dynamo :smiley:


#9

Hi @saju_autodesk
Would you mind dropping a sample rvt & dyn which has the different elements giving different unit outputs?

Thanks,

Mark

Edit: as Martin Spence has just reminded me, if you get the parameters via Python as doubles, (unconverted) they will always be in imperial. This is reliable but more work…


#10

Have you thought about putting dimensions onto the views cropped region in revit as a test, because for my quick test i just did that and this is what the units seem to be. They are in mm and they match the size of the cropped region(not annotation region) which you can see from the following image


#11

HI @Mark.Ackerley

here are the files I am working on …
final formwork_No errors.dyn (256.1 KB)

The Revit file is 5+ mb. and can’t upload here but is same as the sample file that comes in Revit 2018 <<rst_advanced_sample_project>>

The files work perfectly until the units aren’t changed. I wanted to see if the graph works for metric as well and their starts the problem, sometimes the parameter I wish set comes in mm and sometimes in meters and rarely even in ft. ( of course, I closed and reopen every time I ran it).

Thus came my question how to ask dynamo to give you volume and area in the units set in Revit.


#12

Hi @Brendan_Cassidy,
Thanks, but did you check after swapping the units in revit…? or using the same graph in imperial projects?


#13

I followed the same approach as what i did in my reply above, though i changed project units in between with my findings below.

Started with imperial template:

Changed units to Metric: