[graphite] Simplify direction handling

src/hb-graphite2.cc

@@ -248,19 +248,19 @@ _hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
       gr_fref_set_feature_value (fref, features[i].value, feats);
   }
 
-  hb_direction_t target_direction = buffer->props.direction;
+  hb_direction_t direction = buffer->props.direction;
   hb_direction_t horiz_dir = hb_script_get_horizontal_direction (buffer->props.script);
   /* TODO vertical:
    * The only BTT vertical script is Ogham, but it's not clear to me whether OpenType
    * Ogham fonts are supposed to be implemented BTT or not.  Need to research that
    * first. */
-  if ((HB_DIRECTION_IS_HORIZONTAL (target_direction) &&
-       target_direction != horiz_dir && horiz_dir != HB_DIRECTION_INVALID) ||
-      (HB_DIRECTION_IS_VERTICAL   (target_direction) &&
-       target_direction != HB_DIRECTION_TTB))
+  if ((HB_DIRECTION_IS_HORIZONTAL (direction) &&
+       direction != horiz_dir && horiz_dir != HB_DIRECTION_INVALID) ||
+      (HB_DIRECTION_IS_VERTICAL   (direction) &&
+       direction != HB_DIRECTION_TTB))
   {
     hb_buffer_reverse_clusters (buffer);
-    buffer->props.direction = HB_DIRECTION_REVERSE (buffer->props.direction);
+    direction = HB_DIRECTION_REVERSE (direction);
   }
 
   gr_segment *seg = nullptr;
@@ -280,7 +280,7 @@ _hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
 		     HB_TAG_NONE, // https://github.com/harfbuzz/harfbuzz/issues/3439#issuecomment-1442650148
 		     feats,
 		     gr_utf32, chars, buffer->len,
-		     2 | (hb_buffer_get_direction (buffer) == HB_DIRECTION_RTL ? 1 : 0));
+		     2 | (direction == HB_DIRECTION_RTL ? 1 : 0));
 
   if (unlikely (!seg)) {
     if (feats) gr_featureval_destroy (feats);
@@ -332,7 +332,7 @@ _hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
   float yscale = (float) font->y_scale / upem;
   yscale *= yscale / xscale;
   unsigned int curradv = 0;
-  if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+  if (HB_DIRECTION_IS_BACKWARD (direction))
   {
     curradv = gr_slot_origin_X(gr_seg_first_slot(seg)) * xscale;
     clusters[0].advance = gr_seg_advance_X(seg) * xscale - curradv;
@@ -361,7 +361,7 @@ _hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
       c->num_chars = before - c->base_char;
       c->base_glyph = ic;
       c->num_glyphs = 0;
-      if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+      if (HB_DIRECTION_IS_BACKWARD (direction))
       {
 	c->advance = curradv - gr_slot_origin_X(is) * xscale;
 	curradv -= c->advance;
@@ -380,7 +380,7 @@ _hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
 	clusters[ci].num_chars = after + 1 - clusters[ci].base_char;
   }
 
-  if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+  if (HB_DIRECTION_IS_BACKWARD (direction))
     clusters[ci].advance += curradv;
   else
     clusters[ci].advance += gr_seg_advance_X(seg) * xscale - curradv;
@@ -402,7 +402,7 @@ _hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
   unsigned int currclus = UINT_MAX;
   const hb_glyph_info_t *info = buffer->info;
   hb_glyph_position_t *pPos = hb_buffer_get_glyph_positions (buffer, nullptr);
-  if (!HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
+  if (!HB_DIRECTION_IS_BACKWARD (direction))
   {
     curradvx = 0;
     for (is = gr_seg_first_slot (seg); is; pPos++, ++info, is = gr_slot_next_in_segment (is))
@@ -446,7 +446,6 @@ _hb_graphite2_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
 
   buffer->clear_glyph_flags ();
   buffer->unsafe_to_break ();
-  buffer->props.direction = target_direction;
 
   return true;
 }