How to use the current value of "Influence" to drive itself (Using "Self")

Not sure if this is the correct category, but I couldn’t find a “Drivers” section, so putting it here.

I’m trying to drive the “Influence” value on constraints using another variable while maintaining the ability to modify its own value using the slider.

If anybody is familiar with expressions in After Effects and using “value” to stand in for the current value, this is precisely what I’m trying to do.

As far as I’m aware, I have to use the “Use Self” feature on the driver for this. I can’t find a clear documentation on how to use this.

Ex: The current value is 0.15. The other variable is the distance between two bones. The further the bones become, the more the value decreases.
But if I slide the value of “Influence” to be 0.25, then now the starting value changes to 0.25.

Here’s an example setup:

The “self” is where it should reflect the current value of “Influence”.

This seems like it should be very simple to do, but I can’t find the solution. Please help!

Ohmy, never mind. Figured it out on my own literally a few minutes after posting. :laughing:

It’s “self.influence” for anybody needing to do the same.

Actually, never mind the never mind - this doesn’t completely solve the problem.

While the “self.influence” does set the starting point like After Effects based on the current value, it seems to be impossible to view the current value afterwards and precisely update it.

In AE, I can always click on the returned number of a property to always access the original value and change it.


Ex: If the original value is “0.15”, but the returned value from the expression is “0.5”, the number will update to show “0.5”. However, I could always click on that “0.5” and it’ll show “0.15”, and I can simply change that value to a new number.

However, if I click on the “Influence” value, it shows the expression, not the original value.


And if I type in a new value instead, the driver simply gets overwritten with that single value.

Alternatively, if I use the slider to change the value, I have no idea what the new value is. The value will update and show the returned value (so Blender is still clearly storing the original value in the background), but I seem to have no way to easily see the new value and/or precisely enter a desired value.

The only solution I could think of is to not use self and reference a value stored somewhere else per constraint, but this is a little cumbersome to setup, especially across multiple constraints (currently, 20 different constraints).

Is there a way to simply replicate AE’s behavior here?