How Computers Make Books

2 Letter forms

This chapter covers

• The mathematics of computer-generated curves
• Building letter outlines from curves
• Drawing filled shapes from outlines

We have learned how to build shapes from straight lines and how to draw those lines onto a screen built from pixels or onto paper using ink. If we only ever drew our shapes at one size, we could just use enough tiny little straight lines to build up any shape, including curved ones. However, we might like to draw our shapes at different sizes or display them on devices with different resolutions (there may be 1,200 dots per inch on a commercial printer, for example, but only 200 dots per inch on a computer screen). We don’t really want to store a hundred little lines and their coordinates ...