SVG Tiny 1.2 standard support

[guoyunhe]

Some software, like Qt, only supports SVG Tiny 1.2 standard instead of the full SVG 1.2 standard. The main difference is path data:

https://www.w3.org/TR/SVGTiny12/paths.html#PathData

In Dolphin (a Qt based file manager), SVGO optimzed svgs look broken:

[stapelberg]

This is also relevant for BIMI, which requires an SVG tiny 1.2 file: https://bimigroup.org/implementation-guide/

[strarsis]

@stapelberg: BIMI is interesting, good point! This is the link to the path specs of a 'Full' SVG: https://www.w3.org/TR/SVG/paths.html So now the differences have to be found out and converted in a svgo plugin.

SVG Tiny paths:

• moveto
• closepath
• lineto
• curve/cubic bézier
• curve/quadratic bézier

SVG 'Full' paths:

• moveto
• closepath
• lineto
• curve/cubic bézier
• curve/quadratic bézier
• curve/elliptical arc curve
• path directionality
• reflected control points (advanced)
• zero-length path segments (advanced)

Each of these path operations may also differ between the two standards.