I'm creating a simple flowchart using Tikz, and I'd really like the "decision" nodes to be lozenge-shaped (think "tilted parallelogram") rather than square, in order to fit text better.

Here's a minimal example, which is only the top part of the flow-chart and so doesn't illustrate the worst of the node in terms of text fit, but does show what I've got as opposed to what I would like, which is the "decision" node shape here:

enter image description here




% Define block styles
\tikzstyle{decision} = [diamond, draw, text width=10em, text badly centered, node distance=3cm, inner sep=0pt]
\tikzstyle{line} = [draw, -latex']
\tikzstyle{cloud} = [draw, ellipse, node distance=3cm]


% Nodes
  \node[cloud] (a) {$p_n$ is proposed.};
  \node[decision, below of=a] (b) {Has a positum $\phi$ been admitted?};
  \node[decision, below left of=b] (c) {Is $p_n$ true?};
  \node[cloud, below right of=b] (g) {Nothing happens.};

% Edges
  \path [line] (a) -- (b);
  \path [line] (b) -- node {no}(g);
  \path [line] (b) -- node {yes}(c);

  • I think you can refer to: TikZ picture shapes, of which this may be a duplicate. – Claudio Fiandrino Apr 30 '13 at 13:52
  • I was at that post before opening my own question. The instructions there give the standard square diamond, as in my minimal code above, and is not what I want. (Unless the instructions for the squashed diamond are in fact buried in the replies somewhere and I simply can't find it, in which case a pointer to the relevant snippet would be appreciated). – Sara Apr 30 '13 at 14:09
  • If you want I can update that answer to include the shapes not yet contained there rather than post a new answer here: this to have one single reference for these type of shapes. Do you agree? – Claudio Fiandrino Apr 30 '13 at 14:15
  • 1
    I updated the list of styles in that answer; from your picture just two shapes are missing (manual input and display) since I think it worth a new shape definition. Hope to fix them in short time. – Claudio Fiandrino Apr 30 '13 at 14:37
  • 3
    The "squashed diamond" is achieved by using the aspect key and setting to a value greater than 1. This described (albeit briefly, and without a handy picture) in the PGF Manual (2.10 version section 48.3 "Geometric Shapes" p420). – Mark Wibrow Apr 30 '13 at 16:27