The TikZpingus package

Active a glow around the penguin:

copy\begin{tikzpicture}
\pingu[glow=green]
\end{tikzpicture}


Will pass on the color to /pingu/glow and use a /pingu/glow width function width a thicker line width:

copy\begin{tikzpicture}
\pingu[glow thick=green]
\end{tikzpicture}


Will pass on the color to /pingu/glow and use a /pingu/glow width function combined with /pingu/glow function to create a solid glow:

copy\begin{tikzpicture}
\pingu[glow solid=green, wings wave]
\end{tikzpicture}


Requires glow.

Comma separated list of discrete intervals for the glow calculation:

copy\begin{tikzpicture}
\pingu[glow=green, glow steps={.3,.5,1}]
\end{tikzpicture}


Requires glow.

Function using the token \i to refer to the current /pingu/glow steps. Its evaluation will be used to determine the opacity of the current step:

copy\begin{tikzpicture}
\pingu[glow=green,
glow function={.5/\i}]
\end{tikzpicture}


Requires glow.

Function using the token \i to refer to the current /pingu/glow steps. Its evaluation will be used to determine the width of the current step:

copy\begin{tikzpicture}
\pingu[glow=green,
glow width function={5mm-\i mm}]
\end{tikzpicture}