; * src/ftfont.c (ftfont_glyph_metrics): Comment on advance rounding.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/ftfont.c b/src/ftfont.c
index d3c836c0f2d..46abe35ff9a 100644
--- a/src/ftfont.c
+++ b/src/ftfont.c
@@ -1572,6 +1572,12 @@ ftfont_glyph_metrics (FT_Face ft_face, int c, int *advance, int *lbearing,
   if (FT_Load_Glyph (ft_face, c, FT_LOAD_DEFAULT) == 0)
     {
       FT_Glyph_Metrics *m = &ft_face->glyph->metrics;
+
+      /* At first glance this might appear to truncate the glyph's
+         horizontal advance, but FreeType internally rounds the
+         advance width to a pixel boundary prior to returning these
+         metrics.  */
+
       *advance = m->horiAdvance >> 6;
       *lbearing = m->horiBearingX >> 6;
       *rbearing = (m->horiBearingX + m->width) >> 6;