Compound angle/mitre help

[jschnare]

I have looked for a parametric way to figure this out to no avail. 

we have a trench that changes direction to another slope and angle.see photo.

i would like to have a family that is parametric that allow for a user to changed the end point and have the sweep stay consistent. we would also need to be able to divide this geometry into two pieces for production. 

[barthbradley]

It's challenging, but doable.  You'll need a few trigonometric parameter formulas.   This may help you write them: 

https://www.revitforum.org/tutorials-tips-tricks/1046-revit-formulas-everyday-usage.html

[ToanDN]

I would approach it similarly to Duct/Pipe/Cable Tray fitting.