Fix two-pass stroking for \xbord, \ybord

The two-pass stroker blindly assumed that the number of points of
the stroked glyph is the same, no matter the size of the stroker.
Unfortunately, this is not the case every time.  In such cases, the
coordinates will only be replaced up to mininum of points of both
glyphs.  It's incredibly hacky, but seems to work well (and look good).

1 files changed, 3 insertions, 2 deletions

diff --git a/libass/ass_render.c b/libass/ass_render.c
index 86dfd3d..d3d53e4 100644
--- a/libass/ass_render.c
+++ b/libass/ass_render.c
@@ -1799,7 +1799,7 @@ get_outline_glyph(ass_renderer_t *render_priv, int symbol,
 
             // 2nd pass if x/y borders are different
             if (render_priv->state.border_x != render_priv->state.border_y) {
-                int i;
+                int i, m;
                 FT_Glyph g;
                 FT_OutlineGlyph go, gi;
 
@@ -1814,7 +1814,8 @@ get_outline_glyph(ass_renderer_t *render_priv, int symbol,
                 // Replace x coordinates
                 go = (FT_OutlineGlyph) info->outline_glyph;
                 gi = (FT_OutlineGlyph) g;
-                for (i = 0; i < go->outline.n_points; i++)
+                m = FFMIN(go->outline.n_points, gi->outline.n_points);
+                for (i = 0; i < m; i++)
                     go->outline.points[i].x = gi->outline.points[i].x;
                 FT_Done_Glyph(g);
             }