Update from https://crrev.com/317530

third_party/ots/test/side-by-side.cc

Index: third_party/ots/test/side-by-side.cc
diff --git a/third_party/ots/test/side-by-side.cc b/third_party/ots/test/side-by-side.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9034a7c565ca058152a1451aa22e86f70f622e65
--- /dev/null
+++ b/third_party/ots/test/side-by-side.cc
@@ -0,0 +1,281 @@
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <fcntl.h>
+#include <ft2build.h>
+#include FT_FREETYPE_H
+#include FT_OUTLINE_H
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#include "opentype-sanitiser.h"
+#include "ots-memory-stream.h"
+
+namespace {
+
+void DumpBitmap(const FT_Bitmap *bitmap) {
+  for (int i = 0; i < bitmap->rows * bitmap->width; ++i) {
+    if (bitmap->buffer[i] > 192) {
+      std::fprintf(stderr, "#");
+    } else if (bitmap->buffer[i] > 128) {
+      std::fprintf(stderr, "*");
+    } else if (bitmap->buffer[i] > 64) {
+      std::fprintf(stderr, "+");
+    } else if (bitmap->buffer[i] > 32) {
+      std::fprintf(stderr, ".");
+    } else {
+      std::fprintf(stderr, " ");
+    }
+
+    if ((i + 1) % bitmap->width == 0) {
+      std::fprintf(stderr, "\n");
+    }
+  }
+}
+
+int CompareBitmaps(const FT_Bitmap *orig, const FT_Bitmap *trans) {
+  int ret = 0;
+
+  if (orig->width == trans->width &&
+      orig->rows == trans->rows) {
+    for (int i = 0; i < orig->rows * orig->width; ++i) {
+      if (orig->buffer[i] != trans->buffer[i]) {
+        std::fprintf(stderr, "bitmap data doesn't match!\n");
+        ret = 1;
+        break;
+      }
+    }
+  } else {
+    std::fprintf(stderr, "bitmap metrics doesn't match! (%d, %d), (%d, %d)\n",
+                 orig->width, orig->rows, trans->width, trans->rows);
+    ret = 1;
+  }
+
+  if (ret) {
+    std::fprintf(stderr, "EXPECTED:\n");
+    DumpBitmap(orig);
+    std::fprintf(stderr, "\nACTUAL:\n");
+    DumpBitmap(trans);
+    std::fprintf(stderr, "\n\n");
+  }
+
+  delete[] orig->buffer;
+  delete[] trans->buffer;
+  return ret;
+}
+
+int GetBitmap(FT_Library library, FT_Outline *outline, FT_Bitmap *bitmap) {
+  FT_BBox bbox;
+  FT_Outline_Get_CBox(outline, &bbox);
+
+  bbox.xMin &= ~63;
+  bbox.yMin &= ~63;
+  bbox.xMax = (bbox.xMax + 63) & ~63;
+  bbox.yMax = (bbox.yMax + 63) & ~63;
+  FT_Outline_Translate(outline, -bbox.xMin, -bbox.yMin);
+
+  const int w = (bbox.xMax - bbox.xMin) >> 6;
+  const int h = (bbox.yMax - bbox.yMin) >> 6;
+
+  if (w == 0 || h == 0) {
+    return -1;  // white space
+  }
+  if (w < 0 || h < 0) {
+    std::fprintf(stderr, "bad width/height\n");
+    return 1;  // error
+  }
+
+  uint8_t *buf = new uint8_t[w * h];
+  std::memset(buf, 0x0, w * h);
+
+  bitmap->width = w;
+  bitmap->rows = h;
+  bitmap->pitch = w;
+  bitmap->buffer = buf;
+  bitmap->pixel_mode = FT_PIXEL_MODE_GRAY;
+  bitmap->num_grays = 256;
+  if (FT_Outline_Get_Bitmap(library, outline, bitmap)) {
+    std::fprintf(stderr, "can't get outline\n");
+    delete[] buf;
+    return 1;  // error.
+  }
+
+  return 0;
+}
+
+int LoadChar(FT_Face face, bool use_bitmap, int pt, FT_ULong c) {
+  static const int kDpi = 72;
+
+  FT_Matrix matrix;
+  matrix.xx = matrix.yy = 1 << 16;
+  matrix.xy = matrix.yx = 0 << 16;
+
+  FT_Int32 flags = FT_LOAD_DEFAULT | FT_LOAD_TARGET_NORMAL;
+  if (!use_bitmap) {
+    // Since the transcoder drops embedded bitmaps from the transcoded one,
+    // we have to use FT_LOAD_NO_BITMAP flag for the original face.
+    flags |= FT_LOAD_NO_BITMAP;
+  }
+
+  FT_Error error = FT_Set_Char_Size(face, pt * (1 << 6), 0, kDpi, 0);
+  if (error) {
+    std::fprintf(stderr, "Failed to set the char size!\n");
+    return 1;
+  }
+
+  FT_Set_Transform(face, &matrix, 0);
+
+  error = FT_Load_Char(face, c, flags);
+  if (error) return -1;  // no such glyf in the font.
+
+  if (face->glyph->format != FT_GLYPH_FORMAT_OUTLINE) {
+    std::fprintf(stderr, "bad format\n");
+    return 1;
+  }
+
+  return 0;
+}
+
+int LoadCharThenCompare(FT_Library library,
+                        FT_Face orig_face, FT_Face trans_face,
+                        int pt, FT_ULong c) {
+  FT_Bitmap orig_bitmap, trans_bitmap;
+
+  // Load original bitmap.
+  int ret = LoadChar(orig_face, false, pt, c);
+  if (ret) return ret;  // 1: error, -1: no such glyph
+
+  FT_Outline *outline = &orig_face->glyph->outline;
+  ret = GetBitmap(library, outline, &orig_bitmap);
+  if (ret) return ret;  // white space?
+
+  // Load transformed bitmap.
+  ret = LoadChar(trans_face, true, pt, c);
+  if (ret == -1) {
+    std::fprintf(stderr, "the glyph is not found on the transcoded font\n");
+  }
+  if (ret) return 1;  // -1 should be treated as error.
+  outline = &trans_face->glyph->outline;
+  ret = GetBitmap(library, outline, &trans_bitmap);
+  if (ret) return ret;  // white space?
+
+  return CompareBitmaps(&orig_bitmap, &trans_bitmap);
+}
+
+int SideBySide(FT_Library library, const char *file_name,
+               uint8_t *orig_font, size_t orig_len,
+               uint8_t *trans_font, size_t trans_len) {
+  FT_Face orig_face;
+  FT_Error error
+      = FT_New_Memory_Face(library, orig_font, orig_len, 0, &orig_face);
+  if (error) {
+    std::fprintf(stderr, "Failed to open the original font: %s!\n", file_name);
+    return 1;
+  }
+
+  FT_Face trans_face;
+  error = FT_New_Memory_Face(library, trans_font, trans_len, 0, &trans_face);
+  if (error) {
+    std::fprintf(stderr, "Failed to open the transcoded font: %s!\n",
+                 file_name);
+    return 1;
+  }
+
+  static const int kPts[] = {100, 20, 18, 16, 12, 10, 8};  // pt
+  static const size_t kPtsLen = sizeof(kPts) / sizeof(kPts[0]);
+
+  static const int kUnicodeRanges[] = {
+    0x0020, 0x007E,  // Basic Latin (ASCII)
+    0x00A1, 0x017F,  // Latin-1
+    0x1100, 0x11FF,  // Hangul
+    0x3040, 0x309F,  // Japanese HIRAGANA letters
+    0x3130, 0x318F,  // Hangul
+    0x4E00, 0x4F00,  // CJK Kanji/Hanja
+    0xAC00, 0xAD00,  // Hangul
+  };
+  static const size_t kUnicodeRangesLen
+      = sizeof(kUnicodeRanges) / sizeof(kUnicodeRanges[0]);
+
+  for (size_t i = 0; i < kPtsLen; ++i) {
+    for (size_t j = 0; j < kUnicodeRangesLen; j += 2) {
+      for (int k = 0; k <= kUnicodeRanges[j + 1] - kUnicodeRanges[j]; ++k) {
+        int ret = LoadCharThenCompare(library, orig_face, trans_face,
+                                      kPts[i],
+                                      kUnicodeRanges[j] + k);
+        if (ret > 0) {
+          std::fprintf(stderr, "Glyph mismatch! (file: %s, U+%04x, %dpt)!\n",
+                       file_name, kUnicodeRanges[j] + k, kPts[i]);
+          return 1;
+        }
+      }
+    }
+  }
+
+  return 0;
+}
+
+}  // namespace
+
+int main(int argc, char **argv) {
+  if (argc != 2) {
+    std::fprintf(stderr, "Usage: %s ttf_or_otf_filename\n", argv[0]);
+    return 1;
+  }
+
+  // load the font to memory.
+  const int fd = ::open(argv[1], O_RDONLY);
+  if (fd < 0) {
+    ::perror("open");
+    return 1;
+  }
+
+  struct stat st;
+  ::fstat(fd, &st);
+  const off_t orig_len = st.st_size;
+
+  uint8_t *orig_font = new uint8_t[orig_len];
+  if (::read(fd, orig_font, orig_len) != orig_len) {
+    std::fprintf(stderr, "Failed to read file!\n");
+    return 1;
+  }
+  ::close(fd);
+
+  // check if FreeType2 can open the original font.
+  FT_Library library;
+  FT_Error error = FT_Init_FreeType(&library);
+  if (error) {
+    std::fprintf(stderr, "Failed to initialize FreeType2!\n");
+    return 1;
+  }
+  FT_Face dummy;
+  error = FT_New_Memory_Face(library, orig_font, orig_len, 0, &dummy);
+  if (error) {
+    std::fprintf(stderr, "Failed to open the original font with FT2! %s\n",
+                 argv[1]);
+    return 1;
+  }
+
+  // transcode the original font.
+  static const size_t kPadLen = 20 * 1024;
+  uint8_t *trans_font = new uint8_t[orig_len + kPadLen];
+  ots::MemoryStream output(trans_font, orig_len + kPadLen);
+  ots::OTSContext context;
+
+  bool result = context.Process(&output, orig_font, orig_len);
+  if (!result) {
+    std::fprintf(stderr, "Failed to sanitise file! %s\n", argv[1]);
+    return 1;
+  }
+  const size_t trans_len = output.Tell();
+
+  // perform side-by-side tests.
+  return SideBySide(library, argv[1],
+                    orig_font, orig_len,
+                    trans_font, trans_len);
+}