2.1 Scan conversions of point, line, midpoint algorithm for ellipse

1. Point

Point plotting is accomplished by converting a single coordinate position, furnished by an application program into appropriate operations for the output device in use.
For example, in CRT Monitor an electron beam is turned on.
For black and white raster systems a bit values is set corresponding to specified screen position. Then, as the electron beam sweeps across each horizontal scan line, it emits a burst of electors whenever a value of 1 is encountered.

Line drawing is accomplished by calculating intermediate positions along the line path between two specified endpoint positions.
An output device is then directed to fill in these positions between the endpoints.
Digital devices display a straight line segment by plotting discrete points between the two endpoints.
Discrete coordinate positions along the line path are calculated from the equation of the line and algorithms.