fixed os/2 descent

diff --git a/lib/ttf.c b/lib/ttf.c
index 3774b50..3349aa9 100644 (file)
--- a/lib/ttf.c
+++ b/lib/ttf.c
@@ -405,8 +405,8 @@ static table_os2_t*os2_new(ttf_t*ttf)
        os2->ySuperscriptYOffset = (ttf->head->ymax - ttf->head->ymin)/2;
        os2->yStrikeoutSize = ttf->head->units_per_em / 10;
        os2->yStrikeoutPosition = ymid;
-       os2->usWinAscent = ttf->head->ymax;
-       os2->usWinDescent = ttf->head->ymin<0?0:ttf->head->ymin;
+       os2->usWinAscent = ttf->head->ymax>0?ttf->head->ymax:0;
+       os2->usWinDescent = ttf->head->ymin<0?-ttf->head->ymin:0;
        os2->sxHeight = ymid;
        os2->sCapHeight = height*2/3;
     }