Suppose that I have an mid-high poly model, now suppose that i want to both simplify and modify its own topology, my problem is the following: how to generate the simplified model from a fast or simple reference such as a simple mesh used as cage or a simple shape drawed with the pencil ?

I’m going to describe this with an example.

Imagine that we are in the 2D world, I have a random picture, likely to be complex, for example a human figure, now I draw a square on another piece of paper and I would like to redesign that figure more “squarish” using the square as bounding box.

My problem starts from that idea and goes a little further; since retopoligizing any 3D model having only 1 shape as reference it’s likely to generate an ugly “compressed” mesh ( try the cast modifier with a complex 3D model, especially if it’s taller ), my idea is to assign 1 simple shape at each area, for example, with a 3D model of a human body, I would like to specify a sphere for the head and a cube for each arms, so I can generate a rounded head and more squarish arms.

Advanced options for the angles will be really nice.

This is possible in blender ?