background image
C H A P T E R 1 3
Drawing and Graphics
13-6
About Drawing
Figure 13-6
A polygon
A region is an arbitrary area or set of areas, the outline of which is one or more
closed loops. One of drawing's most powerful capabilities is the ability to work
with regions of arbitrary size, shape, and complexity. You define a region by
drawing its boundary with drawing functions. The boundary can be any set of lines
and shapes (even including other regions) forming one or more closed loops. A
region can be concave or convex, can consist of one connected area or many
separate areas. In Figure 13-7, the region consists of two unconnected areas.
Figure 13-7
A region
Your application can record a sequence of drawing operations in a picture and play
its image back later. Pictures provide a form of graphic data exchange: one program
© 2007-2017, o7 studio » при воспроизведении материала сайта ссылка обязательна