Blackmagic Forum

Not sure if this has already been asked or if it's even possible in fusion but I have a straight polyline (with two points) and I'd like to link only one of the points of the line (the end of the line, not the center) to a tracker.

I want to be able to say "that.point = Tracker1.TrackedCenter1".

Am I even thinking about this correctly? Is there a way in fusion that I can manipulate individual points of a path with expressions?

You can create your Polyline, then right-click the point you want to follow the tracker and Publish the points. Then right-click on the point in the Inspector and choose ConnectTo>Tracker1TrackerPath>Position.

Select the point in the Viewer and Shift+P to Publish. Or right-click in the viewer and point to Polygon#:PolyLine > Publish > Publish Points. A Point Control will appear in the Inspector. You can link that to your tracker.

This works for the Grid Warp also, except that you have to use the Shift+P hotkey because for some reason the entire Publish sub-menu is disabled in the UI.

Other options available through the context menu allow you to Publish to Path, which automatically animates the point and gives you a secondary spline showing the point's path; Publish to XY Path, which does the same thing, except you get separate x and y splines in the Spline viewer; and Publish to Tracker, which creates a Tracker node with the appropriate number of trackers and connects the points to them. Follow Published Points causes the selected points to move with any nearby published points. I've never gotten that to work consistently, though, so I'm not entirely sure what's supposed to happen.

Thanks guys. I just tried it now and it works.