[core] Render half-width glyphs in upright orientation

This change forces glyphs whose natural orientation in vertical writing
mode is 'sideways' to be rendered in upright orientation (only for non complex
text layouts). This is different compared to W3C / browser behavior that is by
default, renders glyphs in their respective natural orientation.

In the future, there  might need to add a new layout property that would control
glyph orientation separately (e.g., text-glyph-orientation: natural | upright).

1 files changed, 2 insertions, 1 deletions

diff --git a/src/mbgl/layout/symbol_layout.cpp b/src/mbgl/layout/symbol_layout.cpp
index be6444bb16..dbf209b414 100644
--- a/src/mbgl/layout/symbol_layout.cpp
+++ b/src/mbgl/layout/symbol_layout.cpp
@@ -314,7 +314,8 @@ void SymbolLayout::prepareSymbols(const GlyphMap& glyphMap, const GlyphPositions
                     /* translate */ textOffset,
                     /* writingMode */ writingMode,
                     /* bidirectional algorithm object */ bidi,
-                    /* glyphs */ glyphMap);
+                    /* glyphs */ glyphMap,
+                    allowVerticalPlacement);
 
                 return result;
             };