Create shape from diagram

Hi

I am planning to create page that allow user to design their own shapes based on my predefined shape.
Those designed shapes can be then used in the palette.

basically, user able to drag and drop shapes from the palette and arrange them
then once click save the diagram added to palette shapes

is this possible?
if yes, is there an example to follow?

The basic idea of adding a node to the Palette with properties that are customized by the user is demonstrated in Adding a Custom Node to a Palette.

However that sample does not demonstrate creating new shapes. Do you have a sketch or screenshot of what kinds of assembly you want your users to be able to do?

@walter
similar to the example you provided. but with
1- the possibility of combining multiple shapes to one.
2- shapes are resize-able.
screenshot for reference