From 903771b6c7689b9eee9a11bac128c42f39833b2e Mon Sep 17 00:00:00 2001
From: Rod Sheeter <rsheeter@google.com>
Date: Mon, 26 Feb 2018 19:50:06 -0800
Subject: [PATCH] [subset] clearer name for trim() and better comment about
 composite handling, per review feedback

---
 src/hb-ot-glyf-table.hh |  8 +++++---
 src/hb-subset-glyf.cc   | 17 ++++++++---------
 2 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/hb-ot-glyf-table.hh b/src/hb-ot-glyf-table.hh
index 3d0309777..441d4b9ec 100644
--- a/src/hb-ot-glyf-table.hh
+++ b/src/hb-ot-glyf-table.hh
@@ -276,8 +276,8 @@ struct glyf
     }
 
     /* based on FontTools _g_l_y_f.py::trim */
-    inline bool trim(unsigned int start_offset,
-                     unsigned int *end_offset) const
+    inline bool remove_padding(unsigned int start_offset,
+                               unsigned int *end_offset) const
     {
       static const int FLAG_X_SHORT = 0x02;
       static const int FLAG_Y_SHORT = 0x04;
@@ -294,7 +294,9 @@ struct glyf
       int16_t num_contours = (int16_t) glyph_header.numberOfContours;
 
       if (num_contours < 0)
-        return true; /* no trimming for composites just yet */
+        /* Trimming for composites not implemented.
+         * If removing hints it falls out of that. */
+        return true;
       else if (num_contours > 0)
       {
         unsigned int glyph_len = *end_offset - start_offset;
diff --git a/src/hb-subset-glyf.cc b/src/hb-subset-glyf.cc
index a97e1b76a..696a74de1 100644
--- a/src/hb-subset-glyf.cc
+++ b/src/hb-subset-glyf.cc
@@ -43,12 +43,14 @@ _calculate_glyf_and_loca_prime_size (const OT::glyf::accelerator_t &glyf,
   for (unsigned int i = 0; i < glyph_ids.len; i++)
   {
     hb_codepoint_t next_glyph = glyph_ids[i];
-    *(instruction_ranges->push()) = 0;
-    *(instruction_ranges->push()) = 0;
+    unsigned int *instruction_start = instruction_ranges->push();
+    unsigned int *instruction_end = instruction_ranges->push();
+    *instruction_start = 0;
+    *instruction_end = 0;
 
     unsigned int start_offset, end_offset;
     if (unlikely (!(glyf.get_offsets(next_glyph, &start_offset, &end_offset)
-                    && glyf.trim(start_offset, &end_offset))))
+                    && glyf.remove_padding(start_offset, &end_offset))))
     {
       DEBUG_MSG(SUBSET, nullptr, "Invalid gid %d", next_glyph);
       continue;
@@ -56,20 +58,17 @@ _calculate_glyf_and_loca_prime_size (const OT::glyf::accelerator_t &glyf,
     if (end_offset - start_offset < OT::glyf::GlyphHeader::static_size)
       continue; /* 0-length glyph */
 
-    unsigned int instruction_start = 0, instruction_end = 0;
     if (drop_hints)
     {
       if (unlikely (!glyf.get_instruction_offsets(start_offset, end_offset,
-                                                  &instruction_start, &instruction_end)))
+                                                  instruction_start, instruction_end)))
       {
         DEBUG_MSG(SUBSET, nullptr, "Unable to get instruction offsets for %d", next_glyph);
         return false;
       }
-      instruction_ranges->array[i * 2] = instruction_start;
-      instruction_ranges->array[i * 2 + 1] = instruction_end;
     }
 
-    total += end_offset - start_offset - (instruction_end - instruction_start);
+    total += end_offset - start_offset - (*instruction_end - *instruction_start);
     /* round2 so short loca will work */
     total += total % 2;
   }
@@ -156,7 +155,7 @@ _write_glyf_and_loca_prime (hb_subset_plan_t              *plan,
   {
     unsigned int start_offset, end_offset;
     if (unlikely (!(glyf.get_offsets (glyph_ids[i], &start_offset, &end_offset)
-                    && glyf.trim(start_offset, &end_offset))))
+                    && glyf.remove_padding(start_offset, &end_offset))))
       end_offset = start_offset = 0;
     unsigned int instruction_start = instruction_ranges[i * 2];
     unsigned int instruction_end = instruction_ranges[i * 2 + 1];