In the previous chapter, we developed the Excavation Planning Manager, code named Yharnam, we wrote few basic tools to create new excavation and view and edit existing excavation. We learned how to calculate the area of the excavation and read and write attributes to the excavation. However, there were some form fields that we have added such as the number of trees and total cost that we didn't tackle. We will learn how to find the cost based by doing extensive spatial operations in this chapter.
In this chapter, we will discuss the following topics: