Bitmapped is the adjective for that same idea: a picture, a font, or a graphic stored as a grid of dots, not as lines and curves. People say bitmapped graphics when they want to set them against vector graphics. You may also meet it as a verb form: to bitmap something is to turn it into that grid, so a bitmapped version of a clean drawing has already been broken into pixels. Once it is bitmapped, making it much larger usually makes it look square and rough. The word lives in computing and design. It is a little technical, but not fancy.