Raster or Sample-based Graphics
•Sample-based graphics: discrete elements (aka samples) are used to describe visual information
–Pixels (picture elements) can be created by
•digitizing images (e.g., digital camera, scanner)
•Pixels can be created using a sample-based “painting” program
•Inputting pixel information by hand (e.g., w/numbers from a computed data set)
•Aspects of the physical world can be sampled for visualization, e.g., temperature across the US
•Example programs: Adobe Photoshop™, GIMP™, Adobe AfterEffects™ (it came out of CS123/CS224!)
•In this coordinate space each pixel is represented by x- and y-coordinates and a color
–
Remember Descartes and that “Cartesian” space we talked about? This is it… it has two axes that are not linearly dependent.
Where they meet is 0,0 (aka the origin) and any location in this 2D space can be referred to by means of coordinates –one number  on each axis.

More on this later in geometric graphics section