ThorVG pImpl idiom caused internal data to be scattered
across hierarchical classes. This refactoring consolidates
the data by inheriting pImpl internally, reducing memory
allocation counts and eliminating unnecessary strategy methods.
If for any reason an invalid glyph is found in text,
it will now be skipped when rendering
(instead of increasing offset by last valid glyph advance).
Issue: #2687
Adds the ability to load some composite glyphs and prevents an error when a composite glyph is used.
Implementation based on ttf glyf table documentation: https://learn.microsoft.com/en-us/typography/opentype/spec/glyf
There are still some missing features like scaling, parent glyph point based positioning etc. I think this is a topic for future work. Howerever, it looks like implemented features are enough for utf-8 latin subset in major fonts.
issue: #2599
ttf is an industry standard format that is the most widely used
in the products. Now thorvg supports the basic features of
the font to supplement the text drawing.
The implementation is followed the ttf spec,
the covered features are:
- horizontal layouting with kerning.
- utf8 -> utf32 converted glyph drawing.
To use the feature, please enable ttf loader:
$meson -Dloaders="ttf_beta, ..."
@Issue: https://github.com/thorvg/thorvg/issues/969
