Consider the following statements with respect to approaches to fill area on raster system:

P: To determine the overlap intervals for scan lines that cross the area.

Q: To start from a given interior position and paint outward from this point until we encounter the specific boundary conditions.

Select the correct answer from the options given below:

Concept:

In raster scan system, electron beam move across the screen one row at a time from top to bottom. In this, electron beam intensity is turned on and off to produce illumination on the screen.

Explanation:

There are two approaches used in area filling on raster systems: one is scan line algorithm and another is seed fill algorithm.

1) Scan line algorithm: determine the overlap intervals for scan lines that cross the area or scan line. A scan line is a line of pixels that are plotted on display device when electron beam scans the display area horizontally.

2) Seed fill algorithm: It starts from interior position and point outward from this point until the boundary condition reached. In this, a point is selected and then four or eight connected approaches is used to fill it.