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Tracker X,Y values

PostPosted: Fri Feb 14, 2020 5:53 am
by fredenchine

I'm new to Fusion

I would like to extract x,y value from a tracker and apply them to the Translation x/y of a Transform3D node.

I tried with right click/connect to/tracker/offset x. It works but I need more flexibility with the values (for example, I would like to multiply the x value by 2 or add 0.1 etc).

I also changed my displacement path into X/Y paths, but again, I don't know what to do with that except connecting it directly to my translation field.

Would it be possible to do it with an expression like =GetValue("... ?


Re: Tracker X,Y values

PostPosted: Fri Feb 14, 2020 10:37 am
by Jacob Danell
What you can do is add a slider to your transform3D and use that slider as a multiplyer. So connect your transform3D's center to your tracker using expressions and then multiply it by the slider.

Re: Tracker X,Y values

PostPosted: Fri Feb 14, 2020 10:45 am
by Sander de Regt
What is your intended purpose? The values in the 3D world don't line up with the coordinates in the 2D world anyway, so what are you trying to achieve?

As a practical reply to your question. In your case you don't want to do a direct 'connect to' but you'd do a right-click--modify with--calculation. Then you connect the first value of the calculation to your x/y/whatever and use the calculation add/multiply/subtract with the second value to scale the the values to your liking.

Re: Tracker X,Y values

PostPosted: Fri Feb 14, 2020 1:33 pm
by fredenchine

What I'm trying to do won't be perfect, but it's still better than doing it all manually.

I created "CallOuts" in 3D environment and I inserted them in a latlong sidebyside 3D VR180 video.

For the Z axis, I tried to create a deepthmap and get a Z value from a DispatityToZ node. It gives me something, but it's not precise enough (in the shot, if the object gets a bit brighter or darker, it fails). So, I just calculate my z value manually comparing the disparity of my 3D callout, once rendered into my sbs scene, with the disparity of the object I'm tracking.

But then, for the X and Y values, I would like to use tracker values, and multiply them to get as close as possible to the correct values (at least when I'm staying not too far from the center of the screen, because on the sides of the latlong, the image deformation will be hard to manage).

... I hope my explaination is not too confused :)

Anyway, I've just been using fusion for a few weeks, but being able too use 3D callouts and other 3D objects/effects in a 3DVR environment is pretty cool. If I can track objects, even approximately, it would be perfect.

Re: Tracker X,Y values

PostPosted: Fri Feb 14, 2020 2:44 pm
by fredenchine
Right-click--modify with--calculation, then add a second operand is working ... thanks a lot !

I just need to figure out the second operand now :)

EDIT : It wont work that way, I need to rethink my method, but anyway thanks, now I understand better the way "connect" and "modify" work.