Subset Noto Sans Symbols in a curated way.

Noto Sans Symbols is now subsetted in a curated way. Changes include:

* Currency symbols now included in Roboto are removed.

* All combining marks for symbols (except for combining keycap) are
  added, to combine with other symbols if needed.

* Characters in symbol blocks that are also covered by Noto CJK fonts
  are added, for better harmony with the rest of the fonts in non-CJK
  settings. The dentistry characters at U+23BE..23CC are not added,
  since they appear to be Japan-only and full-width.

* Characters that UTR #51 defines as default text are added, although
  they may also exist in the color emoji font, to make sure they get
  a default text style.

* Characters that UTR #51 defines as default emoji are removed, to
  make sure they don't block the fallback to the color emoji font.

* A few math symbols that are currently included in Roboto are added,
  to prepare for potentially removing them from Roboto when they are
  lower-quality in Roboto.

The superset font, NotoSansSymbols-Regular.ttf is also updated to the
result of 'make android' target in upstream Noto, catching up with
the rest of the fonts.

Bug: 17244669
Bug: 20954421
Bug: 21500703
Bug: 21501669
Bug: 21502245
Bug: 21502678
Bug: 21503807
Bug: 21503952
Bug: 21517912
Bug: 21518544
Bug: 21520316
Bug: 21521330
Bug: 21524018
Bug: 21524421
Bug: 21525012
Bug: 21525318
Bug: 21525905
Bug: 21561723

Change-Id: I49d8c865339fd35a06af5a2320bbea34e3159955

5 files changed, 202 insertions, 21 deletions

diff --git a/Android.mk b/Android.mk
index 1f71f83..bcd95ef 100644
--- a/Android.mk
+++ b/Android.mk
@@ -212,7 +212,8 @@ font_src_files += \
     NotoSansGeorgian-Regular.ttf \
     NotoSansGeorgian-Bold.ttf \
     NotoSansHebrew-Regular.ttf \
-    NotoSansHebrew-Bold.ttf
+    NotoSansHebrew-Bold.ttf \
+    NotoSansSymbols-Regular-Subsetted.ttf
 endif # !MINIMAL_FONT_FOOTPRINT
 
 $(foreach f, $(font_src_files), $(call build-one-font-module, $(f)))
@@ -220,26 +221,6 @@ build-one-font-module :=
 font_src_files :=
 
 #############################################################################
-# Use a larger subset of Noto Sans Symbols on EXTENDED_FONT_FOOTPRINT
-# builds, but a smaller subset on other devices.
-#############################################################################
-ifeq ($(EXTENDED_FONT_FOOTPRINT),true)
-noto_symbols_src := NotoSansSymbols-Regular-Subsetted-Extended.ttf
-else  # !EXTENDED_FONT_FOOTPRINT
-noto_symbols_src := NotoSansSymbols-Regular-Subsetted.ttf
-endif # EXTENDED_FONT_FOOTPRINT
-
-include $(CLEAR_VARS)
-LOCAL_MODULE := NotoSansSymbols-Regular-Subsetted.ttf
-LOCAL_SRC_FILES := $(noto_symbols_src)
-LOCAL_MODULE_CLASS := ETC
-LOCAL_MODULE_TAGS := optional
-LOCAL_MODULE_PATH := $(TARGET_OUT)/fonts
-include $(BUILD_PREBUILT)
-
-noto_symbols_src :=
-
-#############################################################################
 # Use Noto Color Emoji with all the flags on EXTENDED_FONT_FOOTPRINT builds,
 # but without it on other builds. On SMALLER_FONT_FOOTPRINT devices, no
 # color emoji font is included.
diff --git a/other/NotoSansSymbols-Regular-Subsetted-Extended.ttf b/other/NotoSansSymbols-Regular-Subsetted-Extended.ttf
deleted file mode 100644
index 57ed32c..0000000
--- a/other/NotoSansSymbols-Regular-Subsetted-Extended.ttf
+++ /dev/null
diff --git a/other/NotoSansSymbols-Regular-Subsetted.ttf b/other/NotoSansSymbols-Regular-Subsetted.ttf
index 7c4227e..6495140 100644
--- a/other/NotoSansSymbols-Regular-Subsetted.ttf
+++ b/other/NotoSansSymbols-Regular-Subsetted.ttf
diff --git a/other/NotoSansSymbols-Regular.ttf b/other/NotoSansSymbols-Regular.ttf
index 5f38857..d97bf96 100644
--- a/other/NotoSansSymbols-Regular.ttf
+++ b/other/NotoSansSymbols-Regular.ttf
diff --git a/other/subset_noto_sans_symbols.py b/other/subset_noto_sans_symbols.py
new file mode 100755
index 0000000..3c0a23e
--- /dev/null
+++ b/other/subset_noto_sans_symbols.py
@@ -0,0 +1,200 @@
+#!/usr/bin/python
+# coding=UTF-8
+#
+# Copyright 2014 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Create a curated subset of NotoSansSymbols for Android."""
+
+__author__ = 'roozbeh@google.com (Roozbeh Pournader)'
+
+import sys
+
+from nototools import subset
+from nototools import unicode_data
+
+# Unicode blocks that we want to include in the font
+BLOCKS_TO_INCLUDE = """
+20D0..20FF; Combining Diacritical Marks for Symbols
+2100..214F; Letterlike Symbols
+2190..21FF; Arrows
+2200..22FF; Mathematical Operators
+2300..23FF; Miscellaneous Technical
+2400..243F; Control Pictures
+2440..245F; Optical Character Recognition
+2460..24FF; Enclosed Alphanumerics
+2500..257F; Box Drawing
+2580..259F; Block Elements
+25A0..25FF; Geometric Shapes
+2600..26FF; Miscellaneous Symbols
+2700..27BF; Dingbats
+27C0..27EF; Miscellaneous Mathematical Symbols-A
+27F0..27FF; Supplemental Arrows-A
+2800..28FF; Braille Patterns
+2A00..2AFF; Supplemental Mathematical Operators
+"""
+
+# One-off characters to be included, needed for backward compatibility and
+# supporting various character sets, including ARIB sets and black and white
+# emoji
+ONE_OFF_ADDITIONS = {
+    0x27D0, # ⟐ WHITE DIAMOND WITH CENTRED DOT
+    0x2934, # ⤴ ARROW POINTING RIGHTWARDS THEN CURVING UPWARDS
+    0x2935, # ⤵ ARROW POINTING RIGHTWARDS THEN CURVING DOWNWARDS
+    0x2985, # ⦅ LEFT WHITE PARENTHESIS
+    0x2986, # ⦆ RIGHT WHITE PARENTHESIS
+    0x2B05, # ⬅ LEFTWARDS BLACK ARROW
+    0x2B06, # ⬆ UPWARDS BLACK ARROW
+    0x2B07, # ⬇ DOWNWARDS BLACK ARROW
+    0x2B24, # ⬤ BLACK LARGE CIRCLE
+    0x2B2E, # ⬮ BLACK VERTICAL ELLIPSE
+    0x2B2F, # ⬯ WHITE VERTICAL ELLIPSE
+    0x2B56, # ⭖ HEAVY OVAL WITH OVAL INSIDE
+    0x2B57, # ⭗ HEAVY CIRCLE WITH CIRCLE INSIDE
+    0x2B58, # ⭘ HEAVY CIRCLE
+    0x2B59, # ⭙ HEAVY CIRCLED SALTIRE
+}
+
+# letter-based characters, provided by Roboto
+LETTERLIKE_CHARS_IN_ROBOTO = {
+    0x2100, # ℀ ACCOUNT OF
+    0x2101, # ℁ ADDRESSED TO THE SUBJECT
+    0x2103, # ℃ DEGREE CELSIUS
+    0x2105, # ℅ CARE OF
+    0x2106, # ℆ CADA UNA
+    0x2109, # ℉ DEGREE FAHRENHEIT
+    0x2113, # ℓ SCRIPT SMALL L
+    0x2116, # № NUMERO SIGN
+    0x2117, # ℗ SOUND RECORDING COPYRIGHT
+    0x211E, # ℞ PRESCRIPTION TAKE
+    0x211F, # ℟ RESPONSE
+    0x2120, # ℠ SERVICE MARK
+    0x2121, # ℡ TELEPHONE SIGN
+    0x2122, # ™ TRADE MARK SIGN
+    0x2123, # ℣ VERSICLE
+    0x2125, # ℥ OUNCE SIGN
+    0x2126, # Ω OHM SIGN
+    0x212A, # K KELVIN SIGN
+    0x212B, # Å ANGSTROM SIGN
+    0x212E, # ℮ ESTIMATED SYMBOL
+    0x2132, # Ⅎ TURNED CAPITAL F
+    0x213B, # ℻ FACSIMILE SIGN
+    0x214D, # ⅍ AKTIESELSKAB
+    0x214F, # ⅏ SYMBOL FOR SAMARITAN SOURCE
+}
+
+# default emoji characters in the BMP, based on
+# http://www.unicode.org/draft/Public/emoji/1.0/emoji-data.txt
+# We exclude these, so we don't block color emoji.
+BMP_DEFAULT_EMOJI = {
+    0x231A, # ⌚ WATCH
+    0x231B, # ⌛ HOURGLASS
+    0x23E9, # ⏩ BLACK RIGHT-POINTING DOUBLE TRIANGLE
+    0x23EA, # ⏪ BLACK LEFT-POINTING DOUBLE TRIANGLE
+    0x23EB, # ⏫ BLACK UP-POINTING DOUBLE TRIANGLE
+    0x23EC, # ⏬ BLACK DOWN-POINTING DOUBLE TRIANGLE
+    0x23F0, # ⏰ ALARM CLOCK
+    0x23F3, # ⏳ HOURGLASS WITH FLOWING SAND
+    0x25FD, # ◽ WHITE MEDIUM SMALL SQUARE
+    0x25FE, # ◾ BLACK MEDIUM SMALL SQUARE
+    0x2614, # ☔ UMBRELLA WITH RAIN DROPS
+    0x2615, # ☕ HOT BEVERAGE
+    0x2648, # ♈ ARIES
+    0x2649, # ♉ TAURUS
+    0x264A, # ♊ GEMINI
+    0x264B, # ♋ CANCER
+    0x264C, # ♌ LEO
+    0x264D, # ♍ VIRGO
+    0x264E, # ♎ LIBRA
+    0x264F, # ♏ SCORPIUS
+    0x2650, # ♐ SAGITTARIUS
+    0x2651, # ♑ CAPRICORN
+    0x2652, # ♒ AQUARIUS
+    0x2653, # ♓ PISCES
+    0x267F, # ♿ WHEELCHAIR SYMBOL
+    0x2693, # ⚓ ANCHOR
+    0x26A1, # ⚡ HIGH VOLTAGE SIGN
+    0x26AA, # ⚪ MEDIUM WHITE CIRCLE
+    0x26AB, # ⚫ MEDIUM BLACK CIRCLE
+    0x26BD, # ⚽ SOCCER BALL
+    0x26BE, # ⚾ BASEBALL
+    0x26C4, # ⛄ SNOWMAN WITHOUT SNOW
+    0x26C5, # ⛅ SUN BEHIND CLOUD
+    0x26CE, # ⛎ OPHIUCHUS
+    0x26D4, # ⛔ NO ENTRY
+    0x26EA, # ⛪ CHURCH
+    0x26F2, # ⛲ FOUNTAIN
+    0x26F3, # ⛳ FLAG IN HOLE
+    0x26F5, # ⛵ SAILBOAT
+    0x26FA, # ⛺ TENT
+    0x26FD, # ⛽ FUEL PUMP
+    0x2705, # ✅ WHITE HEAVY CHECK MARK
+    0x270A, # ✊ RAISED FIST
+    0x270B, # ✋ RAISED HAND
+    0x2728, # ✨ SPARKLES
+    0x274C, # ❌ CROSS MARK
+    0x274E, # ❎ NEGATIVE SQUARED CROSS MARK
+    0x2753, # ❓ BLACK QUESTION MARK ORNAMENT
+    0x2754, # ❔ WHITE QUESTION MARK ORNAMENT
+    0x2755, # ❕ WHITE EXCLAMATION MARK ORNAMENT
+    0x2757, # ❗ HEAVY EXCLAMATION MARK SYMBOL
+    0x2795, # ➕ HEAVY PLUS SIGN
+    0x2796, # ➖ HEAVY MINUS SIGN
+    0x2797, # ➗ HEAVY DIVISION SIGN
+    0x27B0, # ➰ CURLY LOOP
+    0x27BF, # ➿ DOUBLE CURLY LOOP
+    0x2B1B, # ⬛ BLACK LARGE SQUARE
+    0x2B1C, # ⬜ WHITE LARGE SQUARE
+    0x2B50, # ⭐ WHITE MEDIUM STAR
+    0x2B55, # ⭕ HEAVY LARGE CIRCLE
+}
+
+
+def main(argv):
+    """Subset the Noto Symbols font.
+
+    The first argument is the source file name, and the second argument is
+    the target file name.
+    """
+
+    target_coverage = set()
+    # Add all characters in BLOCKS_TO_INCLUDE
+    for first, last, _ in unicode_data._parse_code_ranges(BLOCKS_TO_INCLUDE):
+        target_coverage.update(range(first, last+1))
+
+    # Add one-off characters
+    target_coverage |= ONE_OFF_ADDITIONS
+    # Remove characters preferably coming from Roboto
+    target_coverage -= LETTERLIKE_CHARS_IN_ROBOTO
+    # Remove characters that are supposed to default to emoji
+    target_coverage -= BMP_DEFAULT_EMOJI
+
+    # Remove dentistry symbols, as their main use appears to be for CJK:
+    # http://www.unicode.org/L2/L2000/00098-n2195.pdf
+    target_coverage -= set(range(0x23BE, 0x23CC+1))
+
+    # Remove COMBINING ENCLOSING KEYCAP. It's needed for Android's color emoji
+    # mechanism to work properly
+    target_coverage.remove(0x20E3)
+
+    source_file_name = argv[1]
+    target_file_name = argv[2]
+    subset.subset_font(
+        source_file_name,
+        target_file_name,
+        include=target_coverage)
+
+
+if __name__ == '__main__':
+    main(sys.argv)