Q4Computer Graphics and Multimedia

Polygon filling (also called polygon shading or interior filling) is the process of assigning color values to all pixels that lie within a closed polygon boundary. After scan-converting the polygon edges, filling algorithms determine which pixels are inside the polygon and set their colors.

Common polygon filling algorithms include: Scan-Line Fill (processes each horizontal scan line and fills spans between edge intersections), Flood Fill (starts from a seed point inside the polygon and recursively fills neighboring pixels), and Boundary Fill (fills until a boundary color is encountered). The scan-line algorithm is most efficient for complex polygons.