How to do the intersection colors of the 2 rects

ok i try to explain what i wanna to say here

lets say i have 1 Green Rect, and 1 Yellow Rect

lets say i stack the yellow rect with partially intersection to the Green Rect

but how do make area that both rect intersect make the color like into white ?

which means, when i stack the partially yellow rect to the green rect, i will still see the border of the yellow rect intersect the green rect.

  • -) rofl, i hope someone understand what i m saying… lol…