How to draw a correct cube in 2P persp,freehand


I have a bit trouble drawing cubes in 2point perspective. According to my book (“basic perspective drawing”), you can use the 45 degree vanishing point to establish the correct distance for a square or cube. However this 45VP can only be derived from the top view, which is pretty time consuming. Is there a trick to estimate the 45VP without having to draw the top view first? Or do you use other methods to draw cubes and squares?

Thanx in advance!


Found it! This picture says it all:

DVP is the diagonal or 45 degr vanishing point
MP is the measuring point for establishing the length of the sides

Here is the URL:
It’s very theoretical, but I understand it now.

Ciao qter