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Forums Adobe After Effects Expressions how to link a layer with a rigged expression to a null without messing it up?

  • how to link a layer with a rigged expression to a null without messing it up?

  • Roei Tzoref

    July 23, 2017 at 12:07 pm

    I am looking for a way to link an expression rigged layer to a null and keeping it’s absolute values so there won’t be a shift when I parent it to a null.

    this is what’s happening:

    this is the beginning of a bar chart template I am creating.
    the bar has this expression:
    t1 = key(1).time;
    t2 = key(2).time;
    v1 = 1413;
    v2 = linear(effect(“Slider Control”)(“Slider”),100,0,1413,885);
    ease(time,t1,t2,v1,v2);

    it’s set on the Y position. now I can change the slider and the animation will act according to 0-100. I want to duplicate this bar and spread them on the X axis. it will be with other layers so I need to parent them so I can move them together. when I do, unless my Null is set to the exact same value as the Bar, there will be a shift. I can either set my null to 0, or parent it and then set it manually back into place. I am looking for something more elegant. to parent it with the right code and not have it to offset.

    what’s the magic combination here please? I can’t seem to make toworld work here.

    Thank you

    Roei Tzoref
    After Effects Artist & Instructor
    ♫ Ae Blues Tutorials

  • Walter Soyka

    July 23, 2017 at 12:44 pm

    You don’t want toWorld(), you want fromWorld(). Give this a spin:

    t1 = key(1).time;
    t2 = key(2).time;
    v1 = 1413;
    v2 = linear(effect("Slider Control")("Slider"),100,0,1413,885);
    x = 0;
    y = ease(time,t1,t2,v1,v2);
    (fromWorld([x,y]) + thisLayer.position)[1]

    Walter Soyka
    Designer & Mad Scientist at Keen Live [link]
    Motion Graphics, Widescreen Events, Presentation Design, and Consulting
    @keenlive [twitter]   |   RenderBreak [blog]   |   Profile [LinkedIn]

  • Roei Tzoref

    July 23, 2017 at 10:31 pm

    Thank you Walter. when I paste it, there is a shift on the Y axis.

    here’s the project for you to test it:
    https://drive.google.com/file/d/0B5wyUt17-tu2Y19pcElBUTZkOUU/view?usp=drivesdk

    Roei Tzoref
    After Effects Artist & Instructor
    ♫ Ae Blues Tutorials

  • Roei Tzoref

    July 23, 2017 at 10:56 pm

    it seems that offseting the shape layer group position in space 260 pixels “fixes” it and now parent and unparent has no shift. still can’t make sense of it because I was thinking default location should produce the most neutral state. maybe it because the shape start position is outside the comps dimensions?

    Roei Tzoref
    After Effects Artist & Instructor
    ♫ Ae Blues Tutorials

  • Roei Tzoref

    July 24, 2017 at 12:26 am

    here’s another basic example. a green solid is linked to a position of a red solid. I want to parent it to a null without a jump.

    what expression could help me here?

    here’s the project:
    https://drive.google.com/file/d/0B5wyUt17-tu2YkdBM3ZfQkhpd0E/view?usp=drivesdk

    Roei Tzoref
    After Effects Artist & Instructor
    ♫ Ae Blues Tutorials

  • Roei Tzoref

    July 25, 2017 at 4:40 am

    Hi, What do you think? Is there a way to avoid this jump due to relative coordinates? I can’t find a related thread about it and to/from World goes over my head… maybe if I see the code, I can understand the principle like with some more complex expressions ideas.

    Roei Tzoref
    After Effects Artist & Instructor
    ♫ Ae Blues Tutorials

  • Walter Soyka

    July 25, 2017 at 4:00 pm

    [Roei Tzoref] “Hi, What do you think? Is there a way to avoid this jump due to relative coordinates? I can’t find a related thread about it and to/from World goes over my head… maybe if I see the code, I can understand the principle like with some more complex expressions ideas.”

    Let’s step back to the beginning. You seem to want a mix of absolute and relative positioning. Why?

    When I build bar charts, I go all-out and control just about everything with expressions. Here’s a very simple example of the kind of approach I usually take:

    11540_barchart.aep.zip

    Walter Soyka
    Designer & Mad Scientist at Keen Live [link]
    Motion Graphics, Widescreen Events, Presentation Design, and Consulting
    @keenlive [twitter]   |   RenderBreak [blog]   |   Profile [LinkedIn]

  • Roei Tzoref

    July 25, 2017 at 7:34 pm

    Thanks Walter. I will study this rig. in a first impression it looks quite robust and not that simple.

    I guess I want to “fix” things in more straightforward manner (in my eyes) if that’s at all possible. take a look at just a simple example, is there a code that can overcome it? or do you have to build your rig in advanced knowing this limitation cannot be fixed in a straightforward way (or you could also so say “the way I want it to work”)

    project file: https://drive.google.com/file/d/0B5wyUt17-tu2YkdBM3ZfQkhpd0E/view?usp=drivesdk

    we can leave it just for research purposes, I am curious if this jump can be avoided…

    Roei Tzoref
    After Effects Artist & Instructor
    ♫ Ae Blues Tutorials

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