From 5f1a8961008b93f72acc47336109af3a64e248d0 Mon Sep 17 00:00:00 2001
From: Ebrahim Byagowi <ebrahim@gnu.org>
Date: Thu, 31 Mar 2016 12:26:16 +0000
Subject: [PATCH] Better glyph offset support

---
 src/hb-directwrite.cc | 44 +++++++++++++++++++++++--------------------
 1 file changed, 24 insertions(+), 20 deletions(-)

diff --git a/src/hb-directwrite.cc b/src/hb-directwrite.cc
index 02bb48df7..e574a52ac 100644
--- a/src/hb-directwrite.cc
+++ b/src/hb-directwrite.cc
@@ -689,15 +689,15 @@ _hb_directwrite_shape(hb_shape_plan_t    *shape_plan,
 
   bool backward = HB_DIRECTION_IS_BACKWARD(buffer->props.direction);
 
-  wchar_t lang[4] = {0};
+  const wchar_t lang[4] = {0};
   if (buffer->props.language != NULL) {
-    mbstowcs(lang, hb_language_to_string(buffer->props.language), 4);
+    mbstowcs((wchar_t*) lang, hb_language_to_string (buffer->props.language), 4);
   }
 
   hr = analyzer->GetGlyphs(pchars, length,
     fontFace, FALSE,
-    buffer->props.direction,
-    &runHead->mScript, (const wchar_t*)lang, NULL, NULL, NULL, 0,
+    backward,
+    &runHead->mScript, lang, NULL, NULL, NULL, 0,
     maxGlyphs, clusters, textProperties,
     glyphs, glyphProperties, &actualGlyphs);
 
@@ -716,8 +716,8 @@ _hb_directwrite_shape(hb_shape_plan_t    *shape_plan,
 
     hr = analyzer->GetGlyphs(pchars, length,
       fontFace, FALSE,
-      buffer->props.direction,
-      &runHead->mScript, (const wchar_t*)lang, NULL, NULL, NULL, 0,
+      backward,
+      &runHead->mScript, lang, NULL, NULL, NULL, 0,
       maxGlyphs, clusters, textProperties,
       glyphs, glyphProperties, &actualGlyphs);
   }
@@ -745,7 +745,11 @@ _hb_directwrite_shape(hb_shape_plan_t    *shape_plan,
   int font_size = font->face->get_upem();
   if (font_size < 0)
     font_size = -font_size;
-  int x_mult = (double)font->x_scale / font_size;
+
+  if (font_size < 0)
+	  font_size = -font_size;
+  double x_mult = (double) font->x_scale / font_size;
+  double y_mult = (double) font->y_scale / font_size;
 
   hr = analyzer->GetGlyphPlacements(pchars,
     clusters,
@@ -755,11 +759,11 @@ _hb_directwrite_shape(hb_shape_plan_t    *shape_plan,
     glyphProperties,
     actualGlyphs,
     fontFace,
-    font_size * x_mult,
-    FALSE,
+    font_size,
     FALSE,
+    backward,
     &runHead->mScript,
-    NULL,
+    lang,
     NULL,
     NULL,
     0,
@@ -805,15 +809,10 @@ _hb_directwrite_shape(hb_shape_plan_t    *shape_plan,
 
     /* The rest is crap.  Let's store position info there for now. */
     info->mask = advances[i];
-    info->var1.u32 = offsets[i].ascenderOffset;
-    info->var2.u32 = -offsets[i].advanceOffset;
+    info->var1.i32 = offsets[i].advanceOffset;
+    info->var2.i32 = offsets[i].ascenderOffset;
   }
 
-  free(clusters);
-  free(glyphs);
-  free(textProperties);
-  free(glyphProperties);
-
   /* Set glyph positions */
   buffer->clear_positions ();
   for (unsigned int i = 0; i < glyphs_len; i++)
@@ -822,14 +821,19 @@ _hb_directwrite_shape(hb_shape_plan_t    *shape_plan,
     hb_glyph_position_t *pos = &buffer->pos[i];
 
     /* TODO vertical */
-    pos->x_advance = info->mask;
-    pos->x_offset = backward ? -info->var1.u32 : info->var1.u32;
-    pos->y_offset = info->var2.u32;
+    pos->x_advance = x_mult * (int32_t) info->mask;
+    pos->x_offset = x_mult * (backward ? -info->var1.i32 : info->var1.i32);
+    pos->y_offset = y_mult * info->var2.i32;
   }
 
   if (backward)
     hb_buffer_reverse (buffer);
 
+  free(clusters);
+  free(glyphs);
+  free(textProperties);
+  free(glyphProperties);
+
   /* Wow, done! */
   return true;
 }