After reviewing the NSAttributedString API it seems justified to have
two different functions for additive and multiplicative line spacing
settings. For NSAttributedString they are setLineSpacing and
setLineHeightMultiple.
Using this function, when appropriate, exercises it lessening the
likelihood of code rot.
Since the original function template has been exposed, we can now use it
directly. Also ShapedText::Detail has been removed, because it wouldn't
work across module boundaries.
This commit fixes a regression added during the ShapedText based rewrite
of the class. The minimumHorizontalScale parameter was mistakenly
interpreted as an absolute scale, whereas its meaning in the old
implementation was a relative scalar applied to the Font's horizontal
scale.
This behaviour, previously available in JUCE 7, was missing since the
JUCE 8 changes related to Unicode text drawing.
With this commit, words that are too long to fit in a line are again
broken up, with the caveat, that we can expect this approach to produce
quirks with bidirectional text. We don't expect that such a feature
could be satisfactorily provided for bidirectional text, so this is a
stopgap measure for legacy applications.
Previously, it wasn't safe to access Font instances from multiple
threads because there was a chance that they might reference the same
shared internal state. In this case, calling getTypeface() or getAscent from
two threads simultaneously would cause a race on the typeface and ascent
data members, even though the Font instances appeared to be disjoint.
With this change in place, it is now safe to use Font instances from
multiple threads simultaneously.
It is still an error to modify the same Font instance from multiple
threads without synchronization!
// Fine:
Font a;
Font b = a;
auto futureA = std::async (std::launch::async, [&a] { /* do something with a */ });
auto futureB = std::async (std::launch::async, [&b] { /* do something with b */ });
// Bad idea:
Font f;
auto futureA = std::async (std::launch::async, [&f] { /* do something with f */ });
auto futureB = std::async (std::launch::async, [&f] { /* do something with f */ });
