ABSTRACT
This chapter represents a departure in terms of the sheer number of classes considered. It introduces two additional types that are seen as a part of the essential toolkit in computer graphics toolkit in but remain peripheral knowledge for those in the design disciplines. The raster, a device in computer graphics that employs arrays of pixel values to represent form and image, is a fundamentally different approach to describing form than the vector-based graphics. The raster model is widely known, dominant in many domains of application, and maintains its own body of foundational concepts and techniques. The functionality related to raster data structures was elaborated in stages, moving from purely organizational mechanisms related to storing data in a matrix, to the spatialization of this matrix such that it may interact with vector geometry. The geometry of an arc shares many attributes in common with a circle: both possess a center point, a radius, and lie on a plane.
