hello. wondering if there is an expression to help me achieve this. I have animated axis1 along a motion path. I then have 5 more axes: 2, 3, 4, 5, 6. I want axes 2-6 to be placed exactly along axis1’s path at a specific frame. so, axis2 is at axis1’s position at frame 1, axis3 is at axis1’s position at frame 5, axis4 at frame 10, etc, etc. I do not want these linked axes to move but be locked in space. I want to be able to change axis1’s motion path and have the other axes updates their positions accordingly. any help is greatly appreciated!
axis2 = eval (axis1, 1)
axis3 = eval (axis1, 5)
axis4 = eval (axis1, 10)
oh man. this seems close but its not “freezing” the axis at frame 1, 5, or 10). its almost like its just linking it.
I think eval is on the right track but it doesn’t seem to be working for me. the above expressions are valid, no syntax error, but it does nothing but link my channel to the “master” axis’s channel.
Works here. WIth axis1 being the ‘donor’ having some position keyframes, and axis2 being the target ‘freeze’ axis, right-clicking on axis2’s position in the animation editor and adding an expression of eval(axis1.position,100) makes axis2 take on the position of axis1 at wherever it would be at on frame 100.
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copy that. I have my “donor” axis on a path and I wonder if it has anything to do with that. still has x and y values though so unsure as to what’s happening. gonna keep trying. what version flame are you running?
Oh, do you mean like a 3D Path node you have something connected to using the Offset value to place it along the path?
You can use the eval in the same way, but instead it’d be on the offset value of the 3D path – each "follower” will have to be linked to their own copy of the 3D path. So the expression on the follower offset would be something like eval(path1.parameters.offset.relative,100)
no I just mean I have the “path” button turned on underneath the position fields for my master axis. ultimately trying to position surfaces along a motion path but have them remain static. however, I want to be able to change the shape of the motion path and have the surfaces follow. I want to keep it as modular as possible, hence changing a single motion path and not having to update each axis’s position individually. Looking into the eval again now.
well, I think that is the answer. the eval function doesn’t work when you have “path” turned on for the “donor” master axis. that is rather disappointing! any other ideas are welcome!