chore: change batteries

bin/font-patcher

@@ -6,7 +6,7 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 # Change the script version when you edit this script:
-script_version = "3.6.1"
+script_version = "3.7.1"
 
 version = "2.3.3"
 projectName = "Nerd Fonts"
@@ -135,6 +135,7 @@ class TableHEADWriter:
             positions = {'checksumAdjustment': 2+2+4,
                          'flags': 2+2+4+4+4,
                          'lowestRecPPEM': 2+2+4+4+4+2+2+8+8+2+2+2+2+2,
+                         'avgWidth': 2,
                 }
             where = self.tab_offset + positions[where]
         self.f.seek(where)
@@ -282,6 +283,23 @@ def get_btb_metrics(font):
     win_btb = win_height + win_gap
     return (hhea_btb, typo_btb, win_btb, win_gap)
 
+def get_old_average_x_width(font):
+    """ Determine xAvgCharWidth of the OS/2 table """
+    # Fontforge can not create fonts with old (i.e. prior to OS/2 version 3)
+    # table values, but some very old applications do need them sometimes
+    # https://learn.microsoft.com/en-us/typography/opentype/spec/os2#xavgcharwidth
+    s = 0
+    weights = {
+        'a': 64, 'b': 14, 'c': 27, 'd': 35, 'e': 100, 'f': 20, 'g': 14, 'h': 42, 'i': 63,
+        'j': 3, 'k': 6, 'l': 35, 'm': 20, 'n': 56, 'o': 56, 'p': 17, 'q': 4, 'r': 49,
+        's': 56, 't': 71, 'u': 31, 'v': 10, 'w': 18, 'x': 3, 'y': 18, 'z': 2, 32: 166,
+    }
+    for g in weights:
+        if g not in font:
+            sys.exit("{}: Can not determine ancient style xAvgCharWidth".format(projectName))
+        s += font[g].width * weights[g]
+    return int(s / 1000)
+
 
 class font_patcher:
     def __init__(self, args):
@@ -296,6 +314,7 @@ class font_patcher:
         self.onlybitmaps = 0
         self.essential = set()
         self.config = configparser.ConfigParser(empty_lines_in_values=False, allow_no_value=True)
+        self.xavgwidth = [] # list of ints
 
     def patch(self, font):
         self.sourceFont = font
@@ -409,6 +428,20 @@ class font_patcher:
                 for idx in range(source_font.num_fonts):
                     if not self.args.quiet:
                         print("{}: Tweaking {}/{}".format(projectName, idx + 1, source_font.num_fonts))
+                    xwidth_s = ''
+                    xwidth = self.xavgwidth[idx]
+                    if isinstance(xwidth, int):
+                        if isinstance(xwidth, bool) and xwidth:
+                            source_font.find_table([b'OS/2'], idx)
+                            xwidth = source_font.getshort('avgWidth')
+                            xwidth_s = ' (copied from source)'
+                        dest_font.find_table([b'OS/2'], idx)
+                        d_xwidth = dest_font.getshort('avgWidth')
+                        if d_xwidth != xwidth:
+                            if not self.args.quiet:
+                                print("Changing xAvgCharWidth from {} to {}{}".format(d_xwidth, xwidth, xwidth_s))
+                            dest_font.putshort(xwidth, 'avgWidth')
+                            dest_font.reset_table_checksum()
                     source_font.find_head_table(idx)
                     dest_font.find_head_table(idx)
                     if source_font.flags & 0x08 == 0 and dest_font.flags & 0x08 != 0:
@@ -421,7 +454,8 @@ class font_patcher:
                         dest_font.putshort(source_font.lowppem, 'lowestRecPPEM')
                     if dest_font.modified:
                         dest_font.reset_table_checksum()
-                        dest_font.reset_full_checksum()
+                if dest_font.modified:
+                    dest_font.reset_full_checksum()
             except Exception as error:
                 print("Can not handle font flags ({})".format(repr(error)))
             finally:
@@ -740,19 +774,20 @@ class font_patcher:
         """ Creates list of dicts to with instructions on copying glyphs from each symbol font into self.sourceFont """
 
         box_enabled = self.source_monospaced # Box glyph only for monospaced
+        box_keep = False
         if box_enabled:
             self.sourceFont.selection.select(("ranges",), 0x2500, 0x259f)
             box_glyphs_target = len(list(self.sourceFont.selection))
             box_glyphs_current = len(list(self.sourceFont.selection.byGlyphs))
             if box_glyphs_target > box_glyphs_current:
-                # Sourcefont does not have all of these glyphs, do not mix sets
+                # Sourcefont does not have all of these glyphs, do not mix sets (overwrite existing)
                 if not self.args.quiet and box_glyphs_current > 0:
                     print("INFO: {}/{} box drawing glyphs will be replaced".format(
                         box_glyphs_current, box_glyphs_target))
-                box_keep = False
                 box_enabled = True
             else:
-                box_keep = True # just scale do not copy
+                # Sourcefont does have all of these glyphs
+                # box_keep = True # just scale do not copy (need to scale to fit new cell size)
                 box_enabled = False # Cowardly not scaling existing glyphs, although the code would allow this
 
         # Stretch 'xz' or 'pa' (preserve aspect ratio)
@@ -1157,6 +1192,10 @@ class font_patcher:
             self.font_dim['xmax'] = self.font_dim['width'] # In fact 'xmax' is never used
         # print("FINAL", self.font_dim)
 
+        self.xavgwidth.append(self.args.xavgwidth)
+        if isinstance(self.xavgwidth[-1], int) and self.xavgwidth[-1] == 0:
+            self.xavgwidth[-1] = get_old_average_x_width(self.sourceFont)
+
 
     def get_target_width(self, stretch):
         """ Get the target width (1 or 2 'cell') for a given stretch parameter """
@@ -1757,6 +1796,12 @@ def setup_arguments():
     progressbars_group_parser.add_argument('--no-progressbars',      dest='progressbars',     action='store_false',               help='Don\'t show percentage completion progress bars per Glyph Set')
     parser.set_defaults(progressbars=True)
     parser.add_argument('--also-windows',                            dest='alsowindows',      default=False, action='store_true', help='Create two fonts, the normal and the --windows version')
+    parser.add_argument('--xavgcharwidth',                           dest='xavgwidth',        default=None,  type=int, nargs='?', help='Adjust xAvgCharWidth (optional: concrete value)', const=True)
+    # --xavgcharwidth for compatibility with old applications like notepad and non-latin fonts
+    # Possible values with examples:
+    # <none>  - copy from sourcefont (default)
+    # 0       - calculate from font according to OS/2-version-2
+    # 500     - set to 500
 
     # symbol fonts to include arguments
     sym_font_group = parser.add_argument_group('Symbol Fonts')
@@ -1845,6 +1890,12 @@ def setup_arguments():
         if is_ttc:
             sys.exit(projectName + ": Can not create single font files from True Type Collections")
 
+    if isinstance(args.xavgwidth, int) and not isinstance(args.xavgwidth, bool):
+        if args.xavgwidth < 0:
+            sys.exit(projectName + ": --xavgcharwidth takes no negative numbers")
+        if args.xavgwidth > 16384:
+            sys.exit(projectName + ": --xavgcharwidth takes only numbers up to 16384")
+
     return args