Delaying shape keys firing

I’m doing corrective shapes on my character’s knees. I have the shape key and driver set up, but I want to make the shape key activate later in the leg’s rotation, because as it is now, the deformation happens while the back of the leg is still visible and it looks really deformed. When the leg is completely folded (i.e. kneeling or sitting on your knees etc) the deformation looks ok.

Opening the driver in the Driver Editor doesn’t allow me to add handles or change the driver to bezier curve, etc. Anyone have any tips?

You can use an envelope modifier in the driver graph to achieve this. For example, in the image below, the reference value is 0.5 and the lower bound of the envelope at the control point (the middle box) is 0. So, the shape key’s value will start from 0 and go up accordingly when the value of your expression reaches 0.5. You can tweak the values to suit your situation.


It should. Here’s a pic in 2.91.0:

I had to turn off snapping to frame, that’s all. You can make a new handle by ctrl clicking on the line, or select a control and change its handle type with ‘v’ set keyframe handle type, or select a control and move it anywhere you want (like to 0.5, 0 to make it only start activation at 0.5.)