I want to make an annotation tool for Point Clouds.
For this reason I want to make a rectangle selection like shown in the picture.
At the moment I need to define the position and the size. The height of the bounding box is fix, but I want to select the corners throw the viewer. I just found the possibility to select a Point or to get the coordinates of the viewer. Is it also possible to get coordinate in the Point Cloud coordinate system without selecting a point?
I'm not sure of a method to do exactly what you want, but what I have done in a different scenario is first position something roughly by clicking a point (you could draw the centre of your prism here), and then allow shifting of the object with keyboard callbacks.