[Tex/LaTex] What are the guidelines for making TikZ pictures properly scalable

scalingtikz-pgf

I've just started using TikZ for rendering figures for my Master thesis. I've made a few and they look good in the report. But when I tried using them in my presentation slides, some were too small and others too large. And now I'm trying to remake the figures to make them scale properly but Ḯ'm having difficulties getting it right.

What are the guidelines, if any, in making TikZ pictures scalable, in particularly when you're using nodes? Do you use relative coordinates only and avoid using absolute positioning such as above=1cm of othernode? How do you specify the size of nodes (for now I'm using minimum width and inner sep but they all require absolute sizes such as cm, pt, and so on. How about the text, should you allow that to scale with the nodes or left as it is? What about lines and arrows, should those scale and how do you go about doing that?

Best Answer

I'm afraid there is no simple answer to your question. In TikZ you usually do not want to scale nodes and the text within. (Till Tantau, the author of the package just calls it 'evil'. :) )

By specifying a scaling factor (e.g. \begin{tikzpicture}[scale=<scaling factor>]), every item drawn in the current tikzpicture environment should be scaled to its appropriate size. (This is possible because TikZ produces vector graphics - 'scaleable' graphics, if you like - unlike bitmap graphics that become 'pixelated' when magnified.)

Nodes are a different breed of objects. For one thing they take the font size from the 'surroundings' and they are immune to 'external' transformations. And this is best left like that, I think. There is, however, an option to force nodes to scale according to the scaling factor of the environment: transform shape. (It also forces rotations, etc.) It is also possible to place a node explicitly on a line, with the pos option.

About the absolute dimensions now: you can specify document-specific dimensions too, if that is your need: e.g. \paperheight and \paperwidth work well. Use their fractions and the figures will be adjusted to new page sizes automatically. (They are also used to create the cover page of the TikZ 2.10 manual.)

I'm not sure above=1cm of othernode is a good idea. I'd rather set the node distance parameter (create a new scope, if it does not apply to the whole picture) and use above=of othernode, letting TikZ use the spacing specified earlier. (Of course, if there is only one such node in the whole picture, it can be more comfortable to set the distance only once, by hand.)

I hope I've been of any help.

Related Solutions

[Tex/LaTex] Using scalable sizes for rectangles, circles and nodes in TikZ

You should do your diagram as at the scale you think you want, and then if you want to scale the figur, say to half its size, apply [scale=0.5] option:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{calc}
\begin{document}
\begin{tikzpicture}[blue]
  \draw [ultra thick] (0,0) rectangle (1,1);
  \draw [ultra thick] (2,0.5) circle (0.5) node {$o$};
  \node at (3,0) {$x$};
\end{tikzpicture}

\begin{tikzpicture}[scale=0.5,red]
  \draw [ultra thick] (0,0) rectangle (1,1);
  \draw [ultra thick] (2,0.5) circle (0.5) node {$o$};
  \node at (3,0) {$x$};
\end{tikzpicture}
\end{document}

enter image description here

The blue is the original with a default scale=1.0, and the red is scaled by 50%. Note that the coordinate of the center of the circle, and the location of the nodes is also scaled, and the size of the text is not scaled, which is usually the desired behavior.

If you want to scale the text as well you should have a look at How to scale Tikz drawings and text together?

[Tex/LaTex] Change TikZ’s default coordinate system

You can change the coordinate system with x=<length> and y=<length> as options to a tikzpicture, e.g.

\begin{tikzpicture}[x=0.5cm,y=0.5cm]

however in your case you would probably rather change the node distance, as this defines the distance between nodes when using the above=of syntax:

\begin{tikzpicture}[node distance=0.5cm]

\begin{tikzpicture}[node distance=0.5cm and 0.5cm]

The difference between these two cases is illustrated in the TikZ/PGF manual (§16.5.3 Advanced Placement Options, pages 187-188, for v. 2.10).

You could also set this globally, by using \tikzset, i.e. add

\tikzset{node distance=0.5cm and 0.5cm}

to your preamble.

Best Answer

Related Solutions

[Tex/LaTex] Using scalable sizes for rectangles, circles and nodes in TikZ

[Tex/LaTex] Change TikZ’s default coordinate system

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