Master's Thesis - Computer Graphics and Visualization - TU Delft

2.2.1 The use case model
In this part, a scenario in which a user uses the Culgi GPE to achieve the goal successfully is proposed.
And then based on this scenario, we will analyze the detailed requirements of The Culgi GPE in the
next part.
A user wants to build a Tcl scipt to do chemistry simulation with the Culgi Library. He starts the Culgi
GPE and opens a new file. Then he sees that there are three parts in the interface, they are menus,
module library and canvas. He first chooses the right module he wants in the library, and then he needs
to create the instance of the module in the canvas. Suppose he just does drag and drop, a new instance
of the module is appeared in the canvas. Then he would set some values to the module according to his
target. After repeating these steps several times, he has already collected enough modules to do the
simulation. Then he needs to make sure that the system will run these modules in the right order. After
defining the running order, he runs the program. Finally he exports Tcl script of this program.
2.2.2 Use case model
Based on the scenario, we will define the use case model. The use case model treats the Culgi GPE as a
black box and describes the interaction between external actors (users) and the Culgi GPE. It is about
how a user uses the Culgi GPE and what the Culgi GPE will do in response to the user’s request,
without assuming how the system works internally.
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