1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
-----------------------------------------------------------------------
-- FILE: luaotfload-arabic.lua
-- DESCRIPTION: part of luaotfload / arabic specific support
-----------------------------------------------------------------------
assert(luaotfload_module, "This is a part of luaotfload and should not be loaded independently") {
name = "luaotfload-arabic",
version = "3.27", --TAGVERSION
date = "2024-02-14", --TAGDATE
description = "luaotfload submodule / features",
license = "GPL v2.0",
author = "Marcel Krüger",
copyright = "The LaTeX Project",
}
local unicode = require'luaotfload-unicode'
local ccc = unicode.ccc
local node_new = node.direct.new
local setlink = node.direct.setlink
local is_char = node.direct.is_char
local getnext = node.direct.getnext
-- Mark combining marks
local mcm = {
[0x0654] = true, -- ARABIC HAMZA ABOVE
[0x0655] = true, -- ARABIC HAMZA BELOW
[0x0658] = true, -- ARABIC MARK NOON GHUNNA
[0x06DC] = true, -- ARABIC SMALL HIGH SEEN
[0x06E3] = true, -- ARABIC SMALL LOW SEEN
[0x06E7] = true, -- ARABIC SMALL HIGH YEH
[0x06E8] = true, -- ARABIC SMALL HIGH NOON
[0x08CA] = true, -- ARABIC SMALL HIGH FARSI YEH
[0x08CB] = true, -- ARABIC SMALL HIGH YEH BARREE WITH TWO DOTS BELOW
[0x08CD] = true, -- ARABIC SMALL HIGH ZAH
[0x08CE] = true, -- ARABIC LARGE ROUND DOT ABOVE
[0x08CF] = true, -- ARABIC LARGE ROUND DOT BELOW
[0x08D3] = true, -- ARABIC SMALL LOW WAW
[0x08F3] = true, -- ARABIC SMALL HIGH WAW
}
-- Implement AMTRA from UTR #53.
-- This assumes that the text is already normalized according to NFD. For most
-- fonts, normalizing to NFC should be good enough.
local function reorder_amtra(head, f)
local n = head
while n do
local base, prev = n
prev, n = n, getnext(n)
while true do
local char = is_char(n, f) -- is_char(nil, f) == is_char(0, f) == nil
local this_ccc = ccc[char]
if not this_ccc then break end -- ! This `break` is the hot path
if this_ccc == 33 then
local after_33, tail_33 = n
repeat
tail_33 = after_33
after_33 = getnext(tail_33)
local char = is_char(after_33, f)
local after_ccc = ccc[char]
until after_ccc ~= 33
setlink(prev, after_33)
setlink(tail_33, getnext(base))
setlink(base, n)
if prev == base then
prev = tail_33
end
n = after_33
elseif this_ccc == 220 then
local after_220, tail_220, found = n
repeat
tail_220 = after_220
after_220 = getnext(tail_220)
local char = is_char(after_220, f)
if mcm[char] then found = true end
local after_ccc = ccc[char]
until after_ccc ~= 220
if found then
setlink(prev, after_220)
setlink(tail_220, getnext(base))
setlink(base, n)
if prev == base then
prev = tail_220
end
n = after_220
base = tail_220 -- Because ccc230 should get inserted after this
else
prev, n = tail_220, after_220
end
elseif this_ccc == 230 then
local after_230, tail_230, found = n
repeat
tail_230 = after_230
after_230 = getnext(tail_230)
local char = is_char(after_230, f)
if mcm[char] then found = true end
local after_ccc = ccc[char]
until after_ccc ~= 230
if found then
setlink(prev, after_230)
setlink(tail_230, getnext(base))
setlink(base, n)
if prev == base then
prev = tail_230
end
n = after_230
else
prev, n = tail_220, after_220
end
else
prev, n = n, getnext(n)
end
end
end
return n
end
-- We need to run after normalize and ideally directly afterwards. So try to insert after normalize
-- or default to the start of the list such that normalize can insert itself before us later.
local normalize_index = 0
for i, manipulator in ipairs(fonts.constructors.features.otf.processors.node) do
if manipulator.name == 'normalize' then
normalize_index = i
end
end
fonts.constructors.features.otf.register {
name = 'amtra',
default = 'auto',
description = 'Apply Unicode Arabic Mark Rendering',
initializers = {
node = function(fonttable, value, features)
if values == 'auto' then
features.amtra = fonttable.properties.script == 'arab'
end
end,
},
processors = {
position = normalize_index + 1,
node = function(head, f)
return reorder_amtra(head, f)
end,
},
}
|