Adjust the QgsTextRenderer::calculateScaleFactorForFormat logic
so that small text is scaled up to at least 50 pixels when
calculating text metrics
This avoids tiny differences in calculated text metrics for small
text from affecting how text wrapping is calculated, which can
otherwise result in words at the end of lines "bouncing" from line
to line as layouts and maps are zoomed out
Adds some text layout modes where the line heights are based
on cap heights or font ascent alone
These are required in order to port additional parts of QGIS
text rendering to the QgsTextRenderer class
This allows for either:
- <sup>superscript</sup> / <sub>subscript</sub> components in text,
where the text will be vertically super or subscript aligned
and automatically sized to 2/3rd of the parent font size. Users
can also set a fixed font size for the super/sub script by
including css rules, e.g. <sup style="font-size:33pt">super</sup>
- "vertical-align: super" or "vertical-align: sub" CSS formatting
rules in any other HTML element
Sponsored by OSGEO UK
