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## our quadratic triangle

**From**: |
Robin Bannister |

**Subject**: |
our quadratic triangle |

**Date**: |
Mon, 25 Jan 2021 22:03:41 +0100 |

**User-agent**: |
Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 |

Hallo there
The markup command \triangle has been around since 2005.
The ChordName code guarantees its regular use as a major-seventh option.
This command has a severe bug, as demonstrated by the following code:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% same behaviour from 2.8.8 to 2.22.0
\markup {
\fontsize #-6 { "-6" \triangle ##f }
\fontsize #-4 { "-4" \triangle ##f }
\fontsize #-2 { "-2" \triangle ##f }
\fontsize # 0 { " 0" \triangle ##f }
\fontsize #+2 { "+2" \triangle ##f }
\fontsize #+4 { "+4" \triangle ##f }
\fontsize #+6 { "+6" \triangle ##f }
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
quadratic.pdf shows that the triangle is ok at fontsize 0 but
- at smaller fontsizes it is too small
- at larger fontsizes it is too large.
I suppose most people use a ChordName font size close to its default.

`The triangle may occasionally appear a bit odd to some. But who is to
``say it is actually wrong when there are so many ChordName opinions around?
`

`Looking inside, the triangle size is derived from baseline-skip to which
``a magstep scaling is applied. But since the baseline-skip distance is
``already scaled to the fontsize, the resulting scaling is quadratic.
`On the other hand the line thickness stays unaffected by fontsize.
So it looks like the magstep scaling was applied to the wrong property.

`Commit 136bdc3c4835942f396d57ac78df71d97c43d3e8 indicates what we should
``expect:
` > new command, as robust replacement for unicode Delta/Triangle.
Cheers,
Robin

**
**`quadratic.pdf`

*Description:* Adobe PDF document

**our quadratic triangle**,
*Robin Bannister* **<=**