Hi Alex,
My ideal would be to have the XPresso Null as a child under a Parent. The parent allows then for the initial position. This needs then [local] “Position” instead of “Global Position’ in the set up.
A typical set up to add the initial position, while changing the position over the the project time, results in a problem during start, frame zero.
The Null for the Tracer must be re-positioned to the place it was plus the distance you like to have as individual position. Which is certainly possible, but require an extra Time>Frame request with an Frame Zero Check [Node>Logic> IS Null] to feed a different and then switch to the add new value to current position. Which kind of makes me thing that we can’t avoid the “Global Position” then. Otherwise any parent will overwrite the values..
Lots of stuff, just to avoid the Parent Null as in the example.
The XPresso version to do that has another problem, the MIX. If you change the Switch time from “flat line” to Sine, this mix value has to be adjusted in time so you get really a nice transition. Which would be possible to do in XPresso as well perhaps with a “Mono-Flop”. … and it becomes even more complex. I have even sorted the XGroup for you, so if you like to try, it might be a better start. I have sorted the Nodes as well, to have no crossing lines and to make the flow of information a little bit clearer. Doing XPresso since over a decade have shown me, that any “salad” aesthetic will make it hard to dive in a month or so later, hence my left side is the given or input, the middle always the “computing” and the right side always the result. It is worth it.
As a side note, to use Object inside, e.g., Null.4”, you can set them to relative or absolute in the Attribute Manager, which allows for an much easier use of the XPresso Node. I certainly like XPresso a lot, but I always look for the more usable solution.
What I would simplify would be in the …XPsw_02 file, why having a time switch and a MIX slider, this could be done in one. Note that I have deleted the Constant Nodes as well, as an unused port uses the values in the Attribute Manager. Just animate the Mix slider and you are done.
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Having said that, let me show you an alternative. Which is easily set up, and can be copied and reused many times, has a slider build in, and is set up in seconds.
I use here an Objects>Empty Polygon, in which I have added in the Structure Manager one line, so it has a “point’ at Pos zero [xyz].
This point is then moved forward with a Time Effector set to Attribute Manger>Deform>Object, and set in its Parameters accordingly in position for that movement.
Then I used a Formula Effector in the same way [deformer.object] and here the parameters to get the up and down movement, which is set up for sine by default. The Time slider below is working for the Effector. Note that the Tracer records only one position per frame, so Nyqvist theorem based, there is a limit.
The real beauty with the Formula Effector comes into the game with the falloff. Which is the transition from flat line to sine. Easy to set up, to adjust and to move, all of that visually.
All the best
The reduced XPresso:
…XPsw_02.c4d
https://www.amazon.com/clouddrive/share/5OntXdIK6IrrnsMIP4hdMmung3wd2WnTnMvTc7wlRlg?ref_=cd_ph_share_link_copy
