Summary
This chapter has presented the basic notions of graphics programming
and event-driven programming using the Graphics library
in the distribution of Objective CAML. After having explained the basic
graphical elements (colors, drawing, filling, text and bitmaps) we have
approached the problem of animating them. The mechanism of handling
events in Graphics was then described in a way that allowed the
introduction of a general method of handling user interaction. This was
accomplished by taking a game as model for event-driven programming. To
improve user interactions and to provide interactive graphical components
to the programmer, we have developed a new library called Awi,
which facilitates the construction of graphical interfaces. This library
was used for writing the interface to the imperative calculator.