How to create a form from rectangle to triangle without loft component

[tigerpix]

Hi,

I am trying to create a form that is similar to what I created in Rhino (number 3).
When I use grasshopper and use loft component it gives me a completely different shape.
My question is how I would be able to create such shape so that I can have more control on the form making.
As you see in the attached screenshot the goal is to use Unrollsfr so that I can create the easier.

Thanks,
RECTAGLE TO TRIANGLE LOFT.gh (23.6 KB)
RECTAGLE TO TRIANGLE.3dm (150.2 KB)

[maje90 (Riccardo Majewski)]

notloft.gh (10.0 KB)
This solution might fail if with complete symmetrical shapes (because of “random” rounding).