12. A Display Model
“The world was black and white then.[It] didn’t turn coloruntil sometime in the 1930s.”
This chapter presents a display model (the output part of GUI), giving examples of use and fundamental notions such as screen coordinates, lines, and color. Line, Lines, Polygons, Axis, and Text are examples of Shapes. A Shape is an object in memory that we can display and manipulate on a screen. The next two chapters will explore these classes further, with Chapter 13 focusing on their implementation and Chapter 14 on design issues.