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#!/usr/bin/env python3
#
# Copyright 2013 The Flutter Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import sys, math
from operator import itemgetter
from itertools import groupby
import unicodedata
import fontforge
NAME = "FlutterTest"
# Turn off auto-hinting and enable manual hinting. FreeType skips auto-hinting
# if the font's family name is in a hard-coded "tricky" font list.
TRICKY_NAME = "MingLiU"
EM = 1024
DESCENT = -EM // 4
ASCENT = EM + DESCENT
# -143 and 20 are the underline location and width Ahem uses.
UPOS = -143 * 1000 // EM
UWIDTH = 20 * 1000 // EM
### Font Metadata and Metrics
font = fontforge.font()
font.familyname = TRICKY_NAME
font.fullname = NAME
font.fontname = NAME
# This sets the relevant fields in the os2 table and hhea table.
font.ascent = ASCENT
font.descent = -DESCENT
font.upos = UPOS
font.uwidth = UWIDTH
font.hhea_linegap = 0
font.os2_typolinegap = 0
font.horizontalBaseline = (
("hang", "ideo", "romn"),
(
("latn", "romn", (ASCENT, DESCENT, 0), ()),
("grek", "romn", (ASCENT, DESCENT, 0), ()),
("hani", "ideo", (ASCENT, DESCENT, 0), ()),
),
)
### TrueType Hinting
# Hints are ignored on macOS.
#
# These hints only **vertically** adjust the outlines, for better vertical
# alignment in golden tests. They don't affect the font or the glyphs' public
# metrics available to the framework, so they typically don't affect non-golden
# tests.
#
# The hinting goals are:
#
# 1. Aligning the key points on glyph outlines between glyphs, when different
# types of glyphs are placed side by side. E.g., for a given point size, "p"
# and "É" should never overlap vertically, and "p" and "x" should be
# bottom-aligned.
#
# 2. Aligning the top and the bottom of the "x" glyph with the background. With
# point size = 14, since the em square's y-extent is 3.5 px (256 * 14 / 1024)
# below the baseline and 10.5 px above the baseline, the glyph's CBOX will be
# "rounded out" (3.5 -> 4, 10.5 -> 11). So "x" is going to be misaligned with
# the background by +0.5 px when rasterized without proper grid-fitting.
# Allocate space in cvt.
font.cvt = [0]
# gcd is used to avoid overflowing, this works for the current ASCENT and EM value.
gcd = math.gcd(ASCENT, EM)
# The control value program is for computing the y-offset (in pixels) to move
# the embox's top edge to grid. The end result will be stored to CVT entry 0.
# CVT[0] = (pointSize * ASCENT / EM) - ceil(pointSize * ASCENT / EM)
prep_program = f"""
RTG
PUSHW_1
0
MPS
PUSHW_1
{(ASCENT << 6) // gcd}
MUL
PUSHW_1
{EM // gcd}
DIV
DUP
CEILING
SUB
WCVTP
"""
font.setTableData("prep", fontforge.parseTTInstrs(prep_program))
def glyph_program(glyph):
# Shift Zone 1 by CVT[0]. In FreeType SHZ actually shifts the zone zp2
# points to, instead of top of the stack. That's probably a bug.
instructions = """
SVTCA[0]
PUSHB_4
0
0
0
0
SZPS
MIRP[0000]
SRP2
PUSHB_3
1
1
1
SZP2
SHZ[0]
SZPS
"""
# Round To Grid every on-curve point, but ignore those who are on the ASCENT
# or DESCENT line. This step keeps "p" (ascent flushed) and "É" (descent
# flushed)'s y extents from overlapping each other.
for index, point in enumerate([p for contour in glyph.foreground for p in contour]):
if point.y not in [ASCENT, DESCENT]:
instructions += f"""
PUSHB_1
{index}
MDAP[1]
"""
return fontforge.parseTTInstrs(instructions)
### Creating Glyphs Outlines
def square_glyph(glyph):
pen = glyph.glyphPen()
# Counter Clockwise
pen.moveTo((0, DESCENT))
pen.lineTo((0, ASCENT))
pen.lineTo((EM, ASCENT))
pen.lineTo((EM, DESCENT))
pen.closePath()
glyph.ttinstrs = glyph_program(glyph)
def ascent_flushed_glyph(glyph):
pen = glyph.glyphPen()
pen.moveTo((0, DESCENT))
pen.lineTo((0, 0))
pen.lineTo((EM, 0))
pen.lineTo((EM, DESCENT))
pen.closePath()
glyph.ttinstrs = glyph_program(glyph)
def descent_flushed_glyph(glyph):
pen = glyph.glyphPen()
pen.moveTo((0, 0))
pen.lineTo((0, ASCENT))
pen.lineTo((EM, ASCENT))
pen.lineTo((EM, 0))
pen.closePath()
glyph.ttinstrs = glyph_program(glyph)
def not_def_glyph(glyph):
pen = glyph.glyphPen()
# Counter Clockwise for the outer contour.
pen.moveTo((EM // 8, 0))
pen.lineTo((EM // 8, ASCENT))
pen.lineTo((EM - EM // 8, ASCENT))
pen.lineTo((EM - EM // 8, 0))
pen.closePath()
# Clockwise, inner contour.
pen.moveTo((EM // 4, EM // 8))
pen.lineTo((EM - EM // 4, EM // 8))
pen.lineTo((EM - EM // 4, ASCENT - EM // 8))
pen.lineTo((EM // 4, ASCENT - EM // 8))
pen.closePath()
glyph.ttinstrs = glyph_program(glyph)
def unicode_range(fromUnicode, throughUnicode):
return range(fromUnicode, throughUnicode + 1)
square_codepoints = [
codepoint for l in [
unicode_range(0x21, 0x26),
unicode_range(0x28, 0x6F),
unicode_range(0x71, 0x7E),
unicode_range(0xA1, 0xC8),
unicode_range(0xCA, 0xFF),
[0x131],
unicode_range(0x152, 0x153),
[0x178, 0x192],
unicode_range(0x2C6, 0x2C7),
[0x2C9],
unicode_range(0x2D8, 0x2DD),
[0x394, 0x3A5, 0x3A7, 0x3A9, 0x3BC, 0x3C0],
unicode_range(0x2013, 0x2014),
unicode_range(0x2018, 0x201A),
unicode_range(0x201C, 0x201E),
unicode_range(0x2020, 0x2022),
[0x2026, 0x2030],
unicode_range(0x2039, 0x203A),
[0x2044, 0x2122, 0x2126, 0x2202, 0x2206, 0x220F],
unicode_range(0x2211, 0x2212),
unicode_range(0x2219, 0x221A),
[0x221E, 0x222B, 0x2248, 0x2260],
unicode_range(0x2264, 0x2265),
[
0x22F2, 0x25CA, 0x3007, 0x4E00, 0x4E03, 0x4E09, 0x4E5D, 0x4E8C, 0x4E94, 0x516B, 0x516D,
0x5341, 0x56D7, 0x56DB, 0x571F, 0x6728, 0x6C34, 0x706B, 0x91D1
],
unicode_range(0xF000, 0xF002),
] for codepoint in l
] + [0x70] + [ord(c) for c in "中文测试文本是否正确"]
no_path_codepoints = [
#(codepoint, advance %)
(0x0020, 1),
(0x00A0, 1),
(0x2003, 1),
(0x3000, 1),
(0x2002, 1 / 2),
(0x2004, 1 / 3),
(0x2005, 1 / 4),
(0x2006, 1 / 6),
(0x2009, 1 / 5),
(0x200A, 1 / 10),
(0xFEFF, 0),
(0x200B, 0),
(0x200C, 0),
(0x200D, 0),
]
def create_glyph(name, contour):
glyph = font.createChar(-1, name)
contour(glyph)
glyph.width = EM
return glyph
if square_codepoints:
create_glyph("Square", square_glyph).altuni = square_codepoints
create_glyph("Ascent Flushed", ascent_flushed_glyph).unicode = 0x70
create_glyph("Descent Flushed", descent_flushed_glyph).unicode = 0xC9
create_glyph(".notdef", not_def_glyph).unicode = -1
def create_no_path_glyph(codepoint, advance_percentage):
name = "Zero Advance" if advance_percentage == 0 else (
"Full Advance" if advance_percentage == 1 else f"1/{(int)(1/advance_percentage)} Advance"
)
no_path_glyph = font.createChar(codepoint, name)
no_path_glyph.width = (int)(EM * advance_percentage)
return no_path_glyph
for (codepoint, advance_percentage) in no_path_codepoints:
if (codepoint in square_codepoints):
raise ValueError(f"{hex(codepoint)} is occupied.")
create_no_path_glyph(codepoint, advance_percentage)
font.generate(sys.argv[1] if len(sys.argv) >= 2 else "test_font.ttf")
### Printing Glyph Map Stats
scripts = set()
for glyph in font.glyphs():
if glyph.unicode >= 0:
scripts.add(fontforge.scriptFromUnicode(glyph.unicode))
for codepoint, _, _ in glyph.altuni or []:
scripts.add(fontforge.scriptFromUnicode(codepoint))
script_list = list(scripts)
script_list.sort()
print(f"| \ Script <br />Glyph | {' | '.join(script_list)} |")
print(" | :--- " + " | :----: " * len(script_list) + "|")
for glyph in font.glyphs():
if glyph.unicode < 0 and not glyph.altuni:
continue
glyph_mapping = {}
if glyph.unicode >= 0:
glyph_mapping[fontforge.scriptFromUnicode(glyph.unicode)] = [glyph.unicode]
for codepoint, _, _ in glyph.altuni or []:
script = fontforge.scriptFromUnicode(codepoint)
if script in glyph_mapping:
glyph_mapping[script].append(codepoint)
else:
glyph_mapping[script] = [codepoint]
codepoints_by_script = [glyph_mapping.get(script, []) for script in script_list]
def describe_codepoint_range(codepoints):
if not codepoints:
return ""
codepoints.sort()
codepoint_ranges = [
list(map(itemgetter(1), group))
for key, group in groupby(enumerate(codepoints), lambda x: x[0] - x[1])
]
characters = [chr(c) for c in codepoints]
def map_char(c):
if c == "`":
return "`` ` ``"
if c == "|":
return "`\\|`"
if c.isprintable() and (not c.isspace()):
return f"`{c}`"
return "`<" + unicodedata.name(c, hex(ord(c))) + ">`"
full_list = " ".join([map_char(c) for c in characters])
return "**codepoint(s):** " + ", ".join([
f"{hex(r[0])}-{hex(r[-1])}" if len(r) > 1 else hex(r[0]) for r in codepoint_ranges
]) + "<br />" + "**character(s):** " + full_list
print(
f"| {glyph.glyphname} | {' | '.join([describe_codepoint_range(l) for l in codepoints_by_script])} |"
)