Create a motion path from multiple objects’s position properties

[Raza Ahmad]

Tried and failed:
Extract position data using an XML export of the project. Position data is obfuscated, or at least not matching the format from a keyframe copy paste.

[Raza Ahmad]

Alright, well this is pretty hacky but it works.

Step 1:

Put another Null — the ‘tracker’ null – in the same comp as all the other Nulls (fortunately my nulls are named numerically).

Step 2: Attach this code to the ‘tracker’ null’s position property.


//t=frame number
t=timeToFrames(t = time + thisComp.displayStartTime, fps = 1.0 / thisComp.frameDuration, isDuration = false);
//set min/max for the nulls to pull from numerically
if (t<1) {t=1};
if (t>100){t=100};
// assemble a string to seek
y=t.toString();
z='Null-'+y;
//get position from that null
thisComp.layer(z).transform.position


Step 3:
Bake expression to keyframes, stretch and do all other bits.

a work in progress, i’d still love to hear a better solution if you have one.

[Daniel Waldron]

Would Andrew Kramer’s SureTarget plugin help? Apply it to your moving layer and add each null object as a target. You would still have to add a keyframe for when you want the layer to move, but at least the position would be set.

[Raza Ahmad]

It’s a good suggestion.

I haven’t used Sure Target in a long time, I kind of put it in the same bucket as Ease and Wizz… super useful in a pinch, but once you go down that road, you spend hours fighting it to try and tweak your animation curves and flow.

Could be it’s time to revisit them both and see if they’ve aged well.

Thanks for the idea.

[Walter Soyka]

I think the expression approach is totally reasonable, but this would also make a pretty straightforward script.

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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