Cineversity

I know this is really dumb question, but I’ve set up a simple Xpresso that drives one object’s position in the Y value based on another object’s Y position.

The problem I’m running into is that about halfway between the lower and upper position, my object intersects. I tried using the Use Spline option on the Range Mapper, but it doesn’t seem to have any effect on the driven objects position.

Any idea why this wouldn’t be working?

Hi Matt,

I could do some guesses here, but a scene file is what delivers facts.

To read the spline is simple and I guess you need no answer here, but on the end the object’s axis counts and its relation to the geometry connected to it.

Talk to you soon.

Hey not a problem! I will send you the file privately.

Thanks, Matt, I got the file.

There are two things here, whereby the first one changes the conditions for the second one. With that, the adjustments via Range Mapper for the second part will change, while you change it.

(Side note: To name the SSD object and the Polygon Object [child] in the same way is creating confusion in the XPresso, which one is in use? You might know it now, but in three months …!?)
The problem continues: the children of parent objects might look like they are around P.Y zero, but the Global P.Y is something complete different (most of the time).
(Tip: Coordinate Manager, not the one in the Attribute Manger> Set to World give you the Global)

Let’s say the Global P.Y is around 200 but the Range Mapper is set to 0-1 or something like that as in the image. What happens now, if not clamped, that the spline curve’s direction is continued, as if it was always just a straight line in the spline field, so the larger (or much smaller, e.g. negative) values will be processed. While there is currently a problem with the Range Mapper, mirroring the the curve to the left, then go straight to linear. This needs way more handling with an lower and upper rangemapper, like an ease in ease out - but for this case, this is way too complex, so let gets the values right before we adjust the curve. In other words, most of the changes in the Spline field might not at all or kind of weirdly affect the positions created by it. To make that point more clear, min and max values behave outside their larger or smaller values as if no spline is used at all. Just a straight line, except for that mirroring.

The best idea is of course to place Result Nodes to the objects you want to work with and to the ones you like to influence, that will give you a hint of what is going on.

Inside of the XPresso Editor>X-manger the list of used Nodes should be sorted from first to last as in top to bottom. Normally it might work, but to avoid problems, sort this stuff for your own peace of mind.

Please check the file I have send via Private Message [link]

My best wishes for your project.

Ahhh yes, having the Result node in there cleared things up for sure! I should have been using actual values, and not 0-1 values within the range mapper.

Thanks so much!

You’re very welcome, Matt, thanks for your feedback.

Yes, the 0-1 seems to work and the Local values might indicate the right use, until Global values are used.

Enjoy.