Coordinate transformation options invalid outside of `tikzpicture`

[muzimuzhi]

Brief outline of the bug

When used outside of tikzpicture, coordinate transformation options, like rotate and xshift, will throw error ! Undefined control sequence. [...] \tikz@transform.

Minimal working example (MWE)

\documentclass{article}
\usepackage{tikz}
\tikzset{rotate=0} % errors

\begin{document}
\end{document}

Direct cause

Currently \tikz@transform is undefined until \tikz@picture sets it to \relax.

More general discussion

Current behavior:

Type	Example	Internals	Use outside of tikzpicture?	Init/Reset at
Coordinate transformation options	rotate, xshift	\tikz@addtransform and \tikz@transform	No, errors	\tikz@picture
Other graphic state options	line width, line cap	\tikz@addoption and \tikz@options	Yes	\tikz@scope@env (inner name of \scope)
Options change mode	draw, fill	\tikz@addmode, \tikz@mode, and other code	Yes	\tikz@scope@env

Expected normalized behavior:

Allow use of these options outside of tikzpicture without errors, but throw warnings to alert users that their effects are discarded at the beginning of tikzpicture.

[ilayn]

These should go inside every x/.style keys in this case every picture/.style={rotate=0}. Otherwise it will never reach to a stable API. you should not write random keys and hope for TikZ doing the right thing. There is not a question of consistency here because the others are working coincidentally.

[muzimuzhi]

These should go inside every x/.style keys in this case every picture/.style={rotate=0}.

Could be added to

• #869

[hmenke]

I've had a look at the internals of \tikz@transform and found that this is in general a highly inconsistent mess. Since the resolution of this bug would actually be merely replace one error with another error, I'm inclined to mark this as closed-wont-fix.

[muzimuzhi]

An "Undefined control sequence" error is just too close to be considered a code bug. Or, at least some words can be added to pgfmanual, maybe just to comfort maintainers, "oh it's (now) documented."