Vertically constraining an angled form

[aa4567345]

Trying to make a family with a vertical portion leading up to an angled one and would like to make the height of the angled portion adjustable by the measurement noted on right of screenshot and without disrupting other dimensions or changing the angle.

Can already do this by dragging the upper reference plane attached to the angled portion but would like to be able to do it by the height measurement itself.

Would this be possible with trigonometric parameters or some other method? Any help appreciated, thanks.

[msgambelluri]

If you still need help with this you may want to consider something unconventional and host geometry on geometry.

See image for concept. You could always make extrusions and revolves not visible

[azad.Nanva]

Do you need something like this ?

[admaecc211151]

In family, I'd like to use trigonometric functions to calculate them, instead of create dim and edit the angle straightly.

Revit just don't know which reference plant I want to move, and which one should be lock.

When you already have x and y, the angle is atan(y/x) . (And you could check it's present by arc or degree later.)