Understanding decorations

The TikZ syntax can be pretty verbose. That’s particularly the case with decorations. Even adding arrow tips along a path can be wordy. As this is an excellent example of what TikZ decorations can do for us, let’s try this.

Let’s create an arrow from (0,0) to (2,0). We can do this with the following code:

\draw[-stealth] (0,0) -- (2,0);

We have an arrow tip at the end of the path, but we also want to have arrow tips along the way. First, we must load the decorations.markings library:

\usetikzlibrary{decorations.markings}

Then, we must choose the decorate option as postaction, with a decoration type of markings, in steps of 0.2 between positions 0.2 and 1:

\draw[-stealth, postaction = decorate,
  decoration = {markings,
  mark = between positions 0.2 and 1 step 0.2
  with {\arrow{stealth}}}]
    (0,0) -- (2,0);

The syntax will be explained in detail later in this chapter...