Filling an area
We already used the fill option in previous chapters. Now, we will take a closer look at filling. Until now, we filled node shapes and simple geometric areas, for example, with \node[fill] and \draw[fill]. There are command aliases:
\fillis equivalent to\path[fill]; we use it for filling without drawing a border\filldrawis equivalent to\path[draw,fill]and\draw[fill]; in this case, we will get a border
Both commands take options for colors, such as \fill[yellow] for yellow filling and \filldraw[fill=yellow,draw=red] for a yellow-filled area with a red border.
If a path encloses an area, TikZ closes it by connecting the last coordinate with the first coordinate, and then it fills it. Of course, it’s good to close the path ourselves by ending with the same coordinate as the path start coordinate. We can do that with a short generic statement by adding -- cycle to the path code, which means connecting finally to the start point. We will...