FAQ/Locator3D
From VFXPedia
To convert coordinates of an object from 3D to 2D space (to get the 2D projection of a 3D point), you need a Camera3D and a Locator3D.
1. If the camera was created not in Fusion, import the camera parameters into the Camera3D node pressing "Import Camera..." in its Controls tab. Fusion supports the following formats: Maya ASCII (.ma), XSI Scene (.xsi), 3Ds Max (.ase), Lightwave (.lws)
2. If the 3D object is animated in Fusion, create a Locator3D node and connect it's coordinates to the object: RMB on the X/Y/Z Offset, select Connect To and choose the animated X/Y/Z parameters.
2.1. If the object was animated in another application, export its coordinates from the application as a locator into one of the formats listed above, then create a Locator3D node and press the "Import Transform..." button in its 3D Controls tab to import the animation from the external file.
2.2. If you want to get coordinates from a point cloud generated by tracking software, create a PointCloud3D node press "Import Point Cloud..." in the Controls tab to import it from an external file (the same format list). Then create a Locator3D. You can position the Locator3D according to the point cloud in three ways:
2.2.1. Select a point of the PointCloud3D in the Display View, RMB in the window, select PointCloud3D>Publish. Then copy the coordinates of the newly published point to the corresponding Locator3D coordinates.
2.2.2. Display the PointCloud3D in a Display View, select the Locator3D and use its "Pick Translation" button from the 3D Controls tab to select a point from the point cloud to which the Locator3D should stick to. This method is less precise and reliable, but it's much faster.
2.2.3. Use the SE_PointCloudFun tool script. It should be copied to your Fusion:\Scripts\Tool and then you can RMB on the PointCloud3D node, select Script>SE_PointCloudFun.
3.Feed the Camera3D output to to the Locator3D 3D Data input.
4. Set appropriate Camera Settings in Locator3D
5. RMB on your 2d-object's Center, select Connect To>Locator3D>Position
