Hector, you’re very welcome! Knowlege is only worth it if you share it, said a friend of mine.
I haven’t had time to look your files yet but one thing I read you’re doing wrong is to set the Z of your container to the focalLength.
The correct position for the focal length is focalLength distant from CAMERA, not world origin, ie., xyz0. Thus, if your camera is at z:-100, your focal length is 100 and you position your container at z:focalLength, your object will be at z:100 and your camera at z:-100. That means your object is 200 away from the camera. Not the focalLength distance. Got it?
To position something in front of your camera at a given distance, use the forward vector of your camera multiplied by the distance you want added to the position of the camera.
Like this (if you want your object to be at focalLength distance from camera):
var camDirection:Vector3D = camera.forwardVector;
camDirection.scaleBy(focalLength);
spriteContainer.position = camera.position.add(camDirection);
This will only work correctly if both camera and container are at the same coordinate space, ie., both are children of the same parent. Else, you’ll have to transform one of the matrices.
