summaryrefslogtreecommitdiff
path: root/macros/luatex/generic/barracuda/lib/lib-geo/libgeo.lua
blob: fd53ca650952bbc20fc6364c3b79d39782ad4a04 (plain)
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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289

-- libgeo simple Geometric Library
-- Copyright (C) 2018 Roberto Giacomelli

-- All dimension must be in scaled point (sp)

local libgeo = {
    _VERSION     = "libgeo v0.0.3",
    _NAME        = "libgeo",
    _DESCRIPTION = "simple geometric library",
}

-- VBar class
-- a pure geometric entity of several infinite vertical lines
libgeo.Vbar = {}
local Vbar = libgeo.Vbar
Vbar.__index = Vbar

-- Vbar costructors

-- VBar costructor from an array [xcenter1, width1, xcenter2, width2, ...]
function Vbar:from_array(yl_arr) --> <vbar object>
    assert(type(yl_arr) == "table", "'yline_array' is a mandatory arg")
    -- stream scanning
    local i = 1
    local xlim = 0.0
    while yl_arr[i] do
        local x = yl_arr[i]; i = i + 1
        local w = yl_arr[i]; i = i + 1
        assert(type(x) == "number", "[InternalErr] not a number")
        assert(type(w) == "number", "[InternalErr] not a number")
        xlim = x + w/2
    end
    assert(i % 2 == 0, "[InternalErr] the index is not even")
    assert(i > 0, "[InternalErr] empty array")
    local o = {
        _yline = yl_arr, -- [<xcenter>, <width>, ...] flat array
        _x_lim = xlim,   -- right external bounding box coordinates
    }
    setmetatable(o, self)
    return o
end

-- costructor useful for Code128 encoder
-- from an integer: 21231 -> binary 11 0 11 000 1 -> symbol 110110001
-- is_bar :: boolean :: bar or space as first element, default true
function Vbar:from_int(ngen, mod, is_bar) --> <vbar object>
    assert(type(ngen) == "number", "Invalid argument for n")
    assert(type(mod) == "number", "Invalid argument for module width")
    if is_bar == nil then is_bar = true else
        assert(type(is_bar) == "boolean", "Invalid argument for is_bar")
    end
    -- scan ngen for digits
    local digits = {}
    while ngen > 0 do
        local d = ngen % 10
        digits[#digits + 1] = d
        ngen = (ngen - d)/10
    end
    local x0 = 0.0 -- axis reference
    local yl = {}
    for k = #digits, 1, -1 do
        local d = digits[k]
        local w = d*mod   -- bar width
        if is_bar then    -- bar
            yl[#yl + 1] = x0 + w/2
            yl[#yl + 1] = w
        end
        x0 = x0 + w
        is_bar = not is_bar
    end
    local o = {
        _yline = yl,   -- [<xcenter>, <width>, ...] flat array
        _x_lim = x0, -- right external coordinate
    }
    setmetatable(o, self)
    return o
end

-- from an integer to read from right to left
-- 13212 ->rev 21231 ->binary 11 0 11 000 1 -> symbol 110110001
-- is_bar :: boolean :: bar or space for first, default true
function Vbar:from_int_revstep(ngen, mod, is_bar) --> <vbar object>
    assert(type(ngen) == "number", "Invalid argument for n")
    assert(type(mod) == "number", "Invalid argument for module width")
    if is_bar == nil then is_bar = true else
        assert(type(is_bar) == "boolean", "Invalid argument for is_bar")
    end
    -- 
    local x0 = 0.0 -- axis reference
    local i = 0
    local yl = {}
    while ngen > 0 do
        local d = ngen % 10 -- first digit
        local w = d*mod     -- bar width
        if is_bar then -- bar
            i = i + 1; yl[i] = x0 + w/2
            i = i + 1; yl[i] = w
        end
        x0 = x0 + w
        is_bar = not is_bar
        ngen = (ngen - d)/10
    end
    assert(not is_bar, "[InternalErr] the last element in not a bar")
    local o = {
        _yline = yl,   -- [<xcenter>, <width>, ...] flat array
        _x_lim = x0, -- right external coordinate
    }
    setmetatable(o, self)
    return o
end

-- costructor useful for Code39 encoder
-- i.e. 11212 -> rev -> 2 1 2 1 1 -> decodes to -> B w B w b
-- build a yline array from the integer definition. Digit decoding rule:
-- mod: b or w => 1 -- narrow bar/space
-- MOD: B or W => 2 -- wide bar/space
-- is_bar: the first element is a bar not a space, default to true
function Vbar:from_int_revpair(ngen, mod, MOD, is_bar) --> <vbar object>
    assert(type(ngen) == "number", "Invalid argument for n")
    assert(type(mod) == "number", "Invalid argument for narrow module width")
    assert(type(MOD) == "number", "Invalid argument for wide module width")
    assert(mod < MOD, "Not ordered narrow/Wide values")
    if is_bar == nil then
        is_bar = true
    else
        assert(type(is_bar) == "boolean", "Invalid argument for 'is_bar'")
    end
    local yl = {}
	local x0 = 0.0
    local k = 0
    while ngen > 0 do
        local d = ngen % 10 -- digit
        ngen = (ngen - d)/10
        local w; if d == 1 then
            w = mod
        elseif d == 2 then
            w = MOD
        end; assert(w, "[InternalErr] Allowed digits are only 1 or 2")
        if is_bar then -- bars
            k = k + 1; yl[k] = x0 + w/2 -- xcenter
            k = k + 1; yl[k] = w        -- width
        end
        is_bar = not is_bar
        x0 = x0 + w
    end
    assert(not is_bar, "[InternalErr] the last element is not a bar")
    local o = {
        _yline = yl, -- [<xcenter>, <width>, ...] flat array
        _x_lim = x0, -- external x coordinate
    }
    setmetatable(o, self)
    return o
end

-- return a Vbar inteleaving to sequence narrow/Wide
-- tbar, tspace = {boolean sequence}, true -> narrow, false -> Wide
function Vbar:from_two_tab(tbar, tspace, mod, MOD) --> <vbar object>
    assert(type(tbar) == "table", "tbar must be a table")
    assert(type(tspace) == "table", "tspace must be a table")
    assert(#tbar == #tspace, "tbar and tspace must be longer the same")
    assert(type(mod) == "number", "Invalid argument for narrow module width")
    assert(type(MOD) == "number", "Invalid argument for wide module width")
    assert(mod < MOD, "Not ordered narrow/Wide values")
    local x0 = 0.0 -- x-coordinate
    local yl = {}
    for i = 1, #tbar do
        local is_narrow = tbar[i]
        assert(type(is_narrow) == "boolean", "[InternalErr] found a not boolean value")
        if is_narrow then
            yl[#yl + 1] = x0 + mod/2 -- bar x-coordinate
            yl[#yl + 1] = mod -- bar width
            x0 = x0 + mod
        else
            yl[#yl + 1] = x0 + MOD/2 -- bar x-coordinate
            yl[#yl + 1] = MOD -- bar width
            x0 = x0 + MOD
        end
        local is_narrow_space = tspace[i]
        assert(type(is_narrow_space) == "boolean", "[InternalErr] found a not boolean value")
        if is_narrow_space then
            x0 = x0 + mod
        else
            x0 = x0 + MOD
        end
    end
    local o = {
        _yline = yl, -- [<xcenter>, <width>, ...] flat array
        _x_lim = x0, -- external x coordinate
    }
    setmetatable(o, self)
    return o
end

-- Text class

libgeo.Text = {}
local Text = libgeo.Text
Text.__index = Text

-- costructors
-- internally it keeps text as a sequence of codepoint
function Text:from_string(s) --> object
    assert(type(s) == "string", "[ArgErr] 's' not a valid string")
    assert(#s > 0, "[Err] 's' empty string not allowed")

    local cp = {} -- codepoint array
    for b in string.gmatch(s, ".") do
        cp[#cp + 1] = string.byte(b)
    end
    local o = {
        codepoint = cp,
    }
    setmetatable(o, self)
    return o
end

-- arr, array of single digit number
-- i start index
-- j stop index
function Text:from_digit_array(arr, i, j) --> object
    assert(type(arr) == "table", "[ArgErr] 'arr' not a table")
    assert(#arr > 0, "[ArgErr] 'arr' is an empty array")
    local cp = {} -- codepoint array
    if i ~= nil then
        assert(type(i) == "number", "[ArgErr] 'i' is not a number")
    else
        i = 1
    end
    if j ~= nil then
        assert(type(j) == "number", "[ArgErr] 'j' is not a number")
        assert(i <= j, "[ArgErr] not suitable pair of array index")
    else
        j = #arr
    end
    for k = i, j do
        local d = arr[k]
        assert(type(d) == "number", "[ArgErr] array contains a not number element")
        assert(d == math.floor(d), "[ArgErr] array contains a not integer number")
        assert(d >= 0 or d < 10, "[ArgErr] array contains a not single digit number")
        cp[#cp + 1] = d + 48
    end
    local o = {
        codepoint = cp,
    }
    setmetatable(o, self)
    return o
end


-- from an array of chars
function Text:from_chars(chars) --> object
    assert(type(chars) == "table", "[ArgErr] 'chars' must be a table")
    local arr = {}
    for _, c in ipairs(chars) do
        arr[#arr + 1] = string.byte(c)
    end
    local o = {
        codepoint = arr,
    }
    setmetatable(o, self)
    return o
end

-- provide an integer to build a Text object
function Text:from_int(n) --> object
    assert(type(n) == "number", "[ArgErr] 'n' must be a number")
    assert( n > 0, "[Err] 'n' must be positive")
    assert( n == math.floor(n), "[Err] 'n' must be an integer")
    local cp = {}
    while n > 0 do
        local d = n % 10
        cp[#cp + 1] = d + 48
        n = (n - d)/10
    end
    local digits = #cp
    for i = 1, digits/2 do -- reverse the array
        local d = cp[digits - i + 1]
        cp[digits - i + 1] = cp[i]
        cp[i] = d
    end
    local o = {
        codepoint = cp,
    }
    setmetatable(o, self)
    return o
end

return libgeo