Angle parameters

Hello everyone,

I created a parametric family with blend and made angle adjustment parameter because I would like to make the trapezium. I would like to join these parameters with grasshopper scripts.

But my problem is that I can only make my trapezium only the direction to the left, cannot to right. If I insert 0 in angle adjustment, it became rectangle. I got error if I insert (-value) in it. How could I solve this problem? If you have any ideas to move to both direction, could you explain it to me?

I attached the rfa.file I have created and the sample video.

Have a nice day, everyone!!

Revit2024.1.rfa (508 KB)


To solve your doubt, you can use the below parameter formulas setup in the family which will allow you to make a -ve value

and your geometry should now be constrained to the refPlane called Control plane

NB: I haven’t gone through the family or checked any errors, but this is the approach you can follow to allow for moving in both directions +ve and -ve

Re_Angle Parameters.rfa (840 KB)

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Thanks a lot. It is the solution for me and it solves in the family data that you have attached.

I tried doing this in my family data but I don`t even know how could I add new parameters to be under “Constraints” like in the picture and when I add new parameters, it was under “Dimensions”.

How could I add parameters like you, could you explain it again? I also don`t know where could I dimension for both C_Angle Adjustment and C_ Angle Adjustment Neg. Do I need to add another reference plane to change to the control plane?

Thanks again for your kindness receiving for your explanation a lot.

Have a nice day!!

Hi Ei Zin,

When adding parameters you can choose the Group that organizes the UI.

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Hello, everyone

Good evening!!

I defined some parameters in my new family file like this way. It worked for the extrusion. But for the void, I do not know where could I define to get equal dimension for angle adjustment (+). Could you please explain it to me? I attached my family data so that you could watch it.

Have a nice day, everyone!!

パラペット.rfa (528 KB)

Can you clarify what you are trying to create or your final geometry and params…Do you want void with the same exact geometry as the solid?

If so you will need to recreate the reference planes (similar to the ones inside the solid blend) and assign same parameters to it [preferably if you knew you will need to use same planes for multiple geometry, you would create the ref planes in the model/family space and not inside the create form command]
Or you can just create a void blend and pick/lock the profile geometry to the existing solid geometry (not a good habit but will save time if you don’t know how to recreate the ref planes) as done in the attached family.

Re_パラペット.rfa (528 KB)

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Good evening!!

Actually, the void and the solid are different geometry. But I want them the same angle rotation. I tried to set the reference line, the control plane and the constraints dimension parameters. But I cannot do it. Could it please explain it more detail how could I set step by step? Do I need to set the parameters first and name the reference line to the control plane?

For me, like this flow, I first did these two things and I got problem after I dimension for positive one, I do not know I could dimension from where to where of the negation dimension. Or do I need the new reference. I got confused how could I do?

Thank you all, for explaining me these days. I am really sorry for the inconvenience of my questions. I know it got frustrating.

Have a nice day, everyone!!


In the below video in the first portion you will find a similar explanation showing how to set up ref planes to have a +/- value, hope it helps.

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Hello, Mr. Mohamed

It helped me. Thank you so much for explaining and sharing me a lot. Have a nice day!!