[Jordan Shipman]

YES! AWESOME! Works perfectly the way I need it to! Thankyou so much Dan!!!! And thankyou for your help as well Juan! I really appreciate it!

[Jordan Shipman]

Thanks fo the response Dan! Hopefully I can get somewhere with this.

here is what I typed in on the lights position:

L = thisComp.layer(” My Null”);
value + fromCompToSurface(L.position);

After effects gives me this error:

Couldn’t project comp point onto layer in fromCompToSurface

Any thoughts?

Thanks for your help?

[Jordan Shipman]

What if the light doesn’t have to interact with a 3D object in a 3D world affected by a 3D camera? What if I just want the light to use the same comp space as the 2D null? Essentially I would be making a 3D light “2D.” But it would still be a “light” object. Is this possible? That seems easier! Thankyou so much for your time and help.

[Jordan Shipman]

Well I don’t think it has to be a true 3d track of an object. As long as I can get a 3d object to follow a 2D point, i can do what I need to do. Is there no way to get a 3D object in after effects to behave like a 2D object in comp space? It seems like you should be able to do that with the layer space transform functions but I’m just not sure exactly how they work.

[Jordan Shipman]

I have camera tracker and thats what I used to track the shot. You can’t manually set track points with camera tracker (as far as I know). I am using the camera created with camera tracker . . . maybe I’m not explaining this well. The camera in after effects is the one produced by cameratracker when I tracked the shot. Because I can’t manually set track points or control them with cameratracker, I had to manually set a motion tracking point in the shot using the built in after effects tools, and then applied that tracking data to a 2d Null object. I need a 3D light object to follow the position of that 2D null object, one way or another so I can get that point to interact with plexus in the shot the way I want it to. Does that make more sense? Ultimately, I need to get a 3D light to follow the position of a 2D null, and I don’t need that 3D light to follow the Z position of anything. It just needs to align properly in the same x and y comp space as the 2D null object, rather than align in world space. Or maybe there is some other way to pull it off. Does this make more sense?

[Jordan Shipman]

Ok, so I have some footage shot on a dolly. I tracked the shot inside after effects using camera tracker and set up a scene. So I have a camera with keyframes. The camera in AE is moving. Using the track points from camera tracker, I created 3D null objects which I then swapped out for lights at the exact same position of the null objects using a script. I’m using plexus with a lights object to create some designs. Now, in that same tracked shot–I’ve used traditional 2D motion tracking inside of AE to track a moving point in the shot and applied that 2D tracking data to a null object. I want to get a 3D light to align with the position of that 2D null object so I can use it to interact with my plexus lights object. If I make the 2D null 3D, then it does not align on my tracked point properly relative to the camera in world space. Only when it is in 2D comp space does it align on my tracked point the way I need it to. If I can get that 3D null to align in world space relative to the camera the way it lines up in 2d comp space, I would be golden. Does all this make sense? Thanks for your help so far!

[Jordan Shipman]

I see what you are saying. I don’t know if this would make a difference–the Z coordinate doesn’t need to change. It can remain constant. But lets say when I manually copy the X and Y values for the 2D null object over to the 3D light and manually set the Z coord for the light–things still don’t line up. Is that because the 2d null is in comp space and the light is in world space? Is there a way to get them to line up?

[Jordan Shipman]

I understand. I think there is a way to do it using expressions and layer space transform methods. I’m just not good enough with expressions to figure out how to make it work.