Line drawing algorithm

A line drawing algorithm is a graphical algorithm for approximating a line segment on discrete graphical media. On discrete media, such as pixel-based displays and printers, line drawing requires such an approximation (in nontrivial cases). Basic algorithms rasterize lines in one color. A better representation with multiple color gradations requires an advanced process, spatial anti-aliasing.

On continuous media, by contrast, no algorithm is necessary to draw a line. For example, oscilloscopes use natural phenomena to draw lines and curves.

The Cartesian slope-intercept equation for a straight line is ${\displaystyle Y=mx+b}$ With m representing the slope of the line and b as the y intercept. Given that the two endpoints of the line segment are specified at positions ${\displaystyle (x1,y1)}$ and ${\displaystyle (x2,y2)}$. we can determine values for the slope m and y intercept b with the following calculations, ${\displaystyle m=(y2-y1)/(x2-x1)}$ so, ${\displaystyle b=y1-m.x1}$.

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