My guess is that it was built in a 3D program. If you wanted to build it in After Effects it can be done but will take longer. You will have to create a rectangle and check the 3D space check box. Make sure you only have the ouline and not the fill. Then create a line the length as one side of the rectangle. Then using the position and rotation you will have to build a triangle. You can parent all of them to a Null if you want to rotate or move the whole 3D triangle. Hope this made some sense. Best of luck.
Stephen Smith
Utah Video Productions
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