This thesis will compare and contrast two algorithms that allow a graphics applications program to communicate with a dot matrix printer (a raster-based device) as a vector device.Graphics devices are commonly grouped into two categories: vector devices and raster devices. A vector device is line-oriented -- e.g., a plotter. In order to plot a line on a vector device, the coordinates of the endpoints of the line are passed to the device and the line is plotted. However, a raster device can be thought of as being composed of a grid of points. A line plotted in a raster environment is an approximation of the line using these points. A dot matrix printer falls into this latter category of graphics devices.The problem at hand is developing a library of graphics routines that allow a dot matrix printer to be addressed in a vector format. The complication that a dot matrix printer raises is that the printer prints a page "typewriter fashion", that is from the top of the page to the bottom, and, on each line, from left to right. This means that each line cannot be immediately printed like on a plotter -- each line must be stored until the page is ready to be printed at which time a line-by-line printing must occur.
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