Cleanup Android build mechanism and pass Android target through subsetter.

The touchup tool is now Android-specific and reads the data from the build
number file directly.  It also lists all glyph going outside the Android
boundaries.  Makefile also has a new 'android' target.

1 files changed, 106 insertions, 0 deletions

diff --git a/scripts/touchup_for_android.py b/scripts/touchup_for_android.py
new file mode 100755
index 0000000..8bcfc14
--- /dev/null
+++ b/scripts/touchup_for_android.py
@@ -0,0 +1,106 @@
+#!/usr/bin/python
+"""Post-build changes for Roboto for Android."""
+
+import os
+from os import path
+import sys
+
+from fontTools import ttLib
+from nototools import font_data
+
+
+def output_protruding_glyphs(font, ymin, ymax, file_name):
+   protruding_glyphs = []
+   glyph_dict = font['glyf'].glyphs
+   for glyph_name, glyph in glyph_dict.items():
+       if glyph.numberOfContours == 0:
+           continue
+       if glyph.yMin < ymin or glyph.yMax > ymax:
+           protruding_glyphs.append(glyph_name)
+   if protruding_glyphs:
+       print "Protruding glyphs in %s:" % file_name,
+       print ', '.join(sorted(protruding_glyphs))
+
+
+def drop_lookup(table, lookup_number):
+    """Drop a lookup from an OpenType table by number.
+    
+    Actually remove pointers from features to the lookup, which should be less
+    intrusive.
+    """
+    for feature in table.table.FeatureList.FeatureRecord:
+        if lookup_number in feature.Feature.LookupListIndex:
+            feature.Feature.LookupListIndex.remove(lookup_number)
+            feature.Feature.LookupCount -= 1
+
+
+def apply_temporary_fixes(font):
+    """Apply some temporary fixes needed for Android."""
+
+    # Remove tab, combining keycap, and the arrows from the cmap table
+    font_data.delete_from_cmap(font, [0x0009, 0x20E3, 0x2191, 0x2193])
+    
+    # Drop the lookup forming the ff ligature
+    drop_lookup(font['GSUB'], 5)
+    
+    # Drop tables not useful on Android
+    for table in ['LTSH', 'hdmx', 'VDMX', 'gasp']:
+        if table in font:
+            del font[table]
+
+    # Fix version number from buildnumber.txt
+    from datetime import date
+
+    build_number_txt = path.join(
+        path.dirname(__file__), os.pardir, 'res', 'buildnumber.txt')
+    build_number = open(build_number_txt).read().strip()
+    version_record = 'Version 2.0%s; %d' % (build_number, date.today().year)
+    for record in font['name'].names:
+        if record.nameID == 5:
+            if record.platformID == 1 and record.platEncID == 0:  # MacRoman
+                record.string = version_record
+            elif record.platformID == 3 and record.platEncID == 1:
+                # Windows UCS-2
+                record.string = version_record.encode('UTF-16BE')
+            else:
+                assert False
+
+
+def correct_font(source_font_name, target_font_name):
+    """Corrects metrics and other meta information."""
+    font = ttLib.TTFont(source_font_name)
+
+    YMAX = 2163
+    YMIN = -555
+    
+    head = font['head']
+    head.yMax = YMAX
+    head.yMin = YMIN
+    output_protruding_glyphs(font, YMIN, YMAX, source_font_name)
+    
+    hhea = font['hhea']
+    hhea.ascent = 1900
+    hhea.descent = -500
+    hhea.lineGap = 0
+    
+    basename = path.basename(source_font_name)
+    bold = ('Bold' in basename) or ('Black' in basename)
+    italic = 'Italic' in basename
+    head.macStyle = (italic << 1) | bold
+    
+    os2 = font['OS/2']
+    os2.fsType = 0
+    os2.achVendID = 'GOOG'
+    
+    apply_temporary_fixes(font)
+    
+    font.save(target_font_name)
+
+
+def main(argv):
+    """Correct the font specified in the command line."""
+    correct_font(argv[1], argv[2])
+
+
+if __name__ == "__main__":
+    main(sys.argv)