When you move the handle of an aligned point of a curve segment, there are two ways it can behave. It will move the opposite handle also, keeping it “aligned” and proportional. As you expand the handle, the opposite one rotates and expands also. The other behavior is that the opposite handle rotates, so it is aligned, but it doesn’t stretch. You can stretch one handle, but not the other. I don’t see a way to switch between the two. What I usually want to do is stretch one handle and not the other. I’m talking about a 3D curve, not a 2D curve. Thanks.
I seem to remember having this issue a long time ago and couldn’t figure out why it was doing that. I work with NURBS 99.9% of the time then and now, so I still don’t know if I’d run into a glitch or accidentally toggled some secret setting.
Having said that, normally you can select a control point, hit* V to bring up the handle type menu, and select the handle type you want to use. Note that the control point is the middle point and the handles are the outer points.
‘Automatic’ and ‘Vector’ will both automatically scale and rotate handles as you move control points around. ‘Aligned’ and ‘Free’ will just move the handles along with the control points. Specifically moving one handle should never scale the other handle, but it can rotate the other handle if the type is ‘Aligned’.
‘Automatic’ automatically converts both handles to ‘Aligned’ when you move a handle, and ‘Vector’ automatically converts the selected handle to ‘Free’. Maybe there is an option somewhere to disable that automatic conversion, in which case it could be you’re stuck in ‘Automatic’.
I hope that helps…
Here is the official info about handle types: https://docs.blender.org/manual/en/5.0/modeling/curves_new/editing/control_points.html#set-handle-type
*or tenderly depress
I don’t use automatic because I want more control. Just a couple days ago, I was trying to stop it from scaling both handles. It wasn’t my imagination. It happens. Maybe switching to “free” and then back to “aligned” would reset it. That seems kind of clunky. I’m using Blender 5.01, but it also did it with previous versions. Maybe I accidentally got automatic. I’ll have to check that out.
Here is a post where someone thought their handles were resizing automatically, but it turned out to be an illusion because they were moving a handle not aligned to the view plane, causing the other handle’s changing orientation to make it look longer or shorter. I could definitely see that throwing me off since I work in 2D axis planes the majority of the time.
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