I want to use the start to finish values of

-1.7 -var = (driver value = 0) to -2.7 -var = (driver value = 1)

I've always done it in the expression as a math formula but I never learned to use the F-Curve to achieve the same results and once in a tutorial they make an example here:


But when I tried this with negative values I could only manage to turn the F-Curve into a mess.

How do you use negative values with F-Curves.


Do you mean, you want the driven property to range from a value of 0 to 1, as the driving property ranges from a value of -2.7 to -1.7?

enter image description here

What we're saying is, we want a function [f(x)=y] where f(-2.7)=0 and f(-1.7)=1. F-curves are function curves. The X and Y are what we want to see on our graph-- points with those X,Y coordinates.

If you look on the sidebar, you can see that the control point I have selected has some fields for manual entry. For this particular control point, it has a value of 0, at a keyframe of -1.7. The other one, naturally, has a value of 1 at a keyframe of -2.7.

You can select a control and manually enter these numbers if you'd like. That's what I did.

If editing these manually ever screws up your handles, and you want it back to being a linear function like I have here, you can select all your controls in the graph editor and use set handle keyframe type ('v' for me) -> vector, which points the handles at the adjacent controls.

Note that in 2.91.0, when you edit a control point to cross another control point (in the x axis), the fcurve re-orders the points, and you lose active selection of the control. It's fine, you just need to reselect.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.