summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/context/base/mkiv/math-act.lua
blob: d0ea789909c355d9dd0107cf4809fc4943318de0 (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
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
if not modules then modules = { } end modules ['math-act'] = {
    version   = 1.001,
    comment   = "companion to math-ini.mkiv",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

-- Here we tweak some font properties (if needed).

local type, next = type, next
local fastcopy = table.fastcopy
local formatters = string.formatters

local trace_defining   = false  trackers.register("math.defining",   function(v) trace_defining   = v end)
local trace_collecting = false  trackers.register("math.collecting", function(v) trace_collecting = v end)

local report_math      = logs.reporter("mathematics","initializing")

local context          = context
local commands         = commands
local mathematics      = mathematics
local texsetdimen      = tex.setdimen
local abs              = math.abs

local sequencers       = utilities.sequencers
local appendgroup      = sequencers.appendgroup
local appendaction     = sequencers.appendaction

local fontchars        = fonts.hashes.characters

local mathfontparameteractions = sequencers.new {
    name      = "mathparameters",
    arguments = "target,original",
}

appendgroup("mathparameters","before") -- user
appendgroup("mathparameters","system") -- private
appendgroup("mathparameters","after" ) -- user

function fonts.constructors.assignmathparameters(original,target)
    local runner = mathfontparameteractions.runner
    if runner then
        runner(original,target)
    end
end

function mathematics.initializeparameters(target,original)
    local mathparameters = original.mathparameters
    if mathparameters and next(mathparameters) then
        target.mathparameters = mathematics.dimensions(mathparameters)
    end
end

sequencers.appendaction("mathparameters","system","mathematics.initializeparameters")

local how = {
 -- RadicalKernBeforeDegree         = "horizontal",
 -- RadicalKernAfterDegree          = "horizontal",
    ScriptPercentScaleDown          = "unscaled",
    ScriptScriptPercentScaleDown    = "unscaled",
    RadicalDegreeBottomRaisePercent = "unscaled"
}

function mathematics.scaleparameters(target,original)
    if not target.properties.math_is_scaled then
        local mathparameters = target.mathparameters
        if mathparameters and next(mathparameters) then
            local parameters = target.parameters
            local factor  = parameters.factor
            local hfactor = parameters.hfactor
            local vfactor = parameters.vfactor
            for name, value in next, mathparameters do
                local h = how[name]
                if h == "unscaled" then
                    -- kept
                elseif h == "horizontal" then
                    value = value * hfactor
                elseif h == "vertical"then
                    value = value * vfactor
                else
                    value = value * factor
                end
               mathparameters[name] = value
            end
        end
        target.properties.math_is_scaled = true
    end
end

sequencers.appendaction("mathparameters","system","mathematics.scaleparameters")

-- AccentBaseHeight vs FlattenedAccentBaseHeight

function mathematics.checkaccentbaseheight(target,original)
    local mathparameters = target.mathparameters
    if mathparameters and mathparameters.AccentBaseHeight == 0 then
        mathparameters.AccentBaseHeight = target.parameters.x_height -- needs checking
    end
end

sequencers.appendaction("mathparameters","system","mathematics.checkaccentbaseheight") -- should go in lfg instead

function mathematics.checkprivateparameters(target,original)
    local mathparameters = target.mathparameters
    if mathparameters then
        local parameters = target.parameters
        local properties = target.properties
        if parameters then
            local size = parameters.size
            if size then
                if not mathparameters.FractionDelimiterSize then
                    mathparameters.FractionDelimiterSize = 1.01 * size
                end
                if not mathparameters.FractionDelimiterDisplayStyleSize then
                    mathparameters.FractionDelimiterDisplayStyleSize = 2.40 * size
                end
            elseif properties then
                report_math("invalid parameters in font %a",properties.fullname or "?")
            else
                report_math("invalid parameters in font")
            end
        elseif properties then
            report_math("no parameters in font %a",properties.fullname or "?")
        else
            report_math("no parameters and properties in font")
        end
    end
end

sequencers.appendaction("mathparameters","system","mathematics.checkprivateparameters")

function mathematics.overloadparameters(target,original)
    local mathparameters = target.mathparameters
    if mathparameters and next(mathparameters) then
        local goodies = target.goodies
        if goodies then
            for i=1,#goodies do
                local goodie = goodies[i]
                local mathematics = goodie.mathematics
                local parameters  = mathematics and mathematics.parameters
                if parameters then
                    if trace_defining then
                        report_math("overloading math parameters in %a @ %p",target.properties.fullname,target.parameters.size)
                    end
                    for name, value in next, parameters do
                        local tvalue = type(value)
                        if tvalue == "string" then
                            report_math("comment for math parameter %a: %s",name,value)
                        else
                            local oldvalue = mathparameters[name]
                            local newvalue = oldvalue
                            if oldvalue then
                                if tvalue == "number" then
                                    newvalue = value
                                elseif tvalue == "function" then
                                    newvalue = value(oldvalue,target,original)
                                elseif not tvalue then
                                    newvalue = nil
                                end
                                if trace_defining and oldvalue ~= newvalue then
                                    report_math("overloading math parameter %a: %S => %S",name,oldvalue,newvalue)
                                end
                            else
                                report_math("invalid math parameter %a",name)
                            end
                            mathparameters[name] = newvalue
                        end
                    end
                end
            end
        end
    end
end

sequencers.appendaction("mathparameters","system","mathematics.overloadparameters")

local function applytweaks(when,target,original)
    local goodies = original.goodies
    if goodies then
        for i=1,#goodies do
            local goodie = goodies[i]
            local mathematics = goodie.mathematics
            local tweaks = mathematics and mathematics.tweaks
            if tweaks then
                tweaks = tweaks[when]
                if tweaks then
                    if trace_defining then
                        report_math("tweaking math of %a @ %p (%s)",target.properties.fullname,target.parameters.size,when)
                    end
                    for i=1,#tweaks do
                        local tweak= tweaks[i]
                        local tvalue = type(tweak)
                        if tvalue == "function" then
                            tweak(target,original)
                        end
                    end
                end
            end
        end
    end
end

function mathematics.tweakbeforecopyingfont(target,original)
    local mathparameters = target.mathparameters -- why not hasmath
    if mathparameters then
        applytweaks("beforecopying",target,original)
    end
end

function mathematics.tweakaftercopyingfont(target,original)
    local mathparameters = target.mathparameters -- why not hasmath
    if mathparameters then
        applytweaks("aftercopying",target,original)
    end
end

sequencers.appendaction("beforecopyingcharacters","system","mathematics.tweakbeforecopyingfont")
sequencers.appendaction("aftercopyingcharacters", "system","mathematics.tweakaftercopyingfont")

function mathematics.overloaddimensions(target,original,set)
    local goodies = target.goodies
    if goodies then
        for i=1,#goodies do
            local goodie = goodies[i]
            local mathematics = goodie.mathematics
            local dimensions  = mathematics and mathematics.dimensions
            if dimensions then
                if trace_defining then
                    report_math("overloading dimensions in %a @ %p",target.properties.fullname,target.parameters.size)
                end
                local characters = target.characters
                local parameters = target.parameters
                local factor     = parameters.factor
                local hfactor    = parameters.hfactor
                local vfactor    = parameters.vfactor
                local addprivate = fonts.helpers.addprivate
                local function overload(dimensions)
                    for unicode, data in next, dimensions do
                        local character = characters[unicode]
                        if character then
                            --
                            local width  = data.width
                            local height = data.height
                            local depth  = data.depth
                            if trace_defining and (width or height or depth) then
                                report_math("overloading dimensions of %C, width %a, height %a, depth %a",unicode,width,height,depth)
                            end
                            if width   then character.width  = width  * hfactor end
                            if height  then character.height = height * vfactor end
                            if depth   then character.depth  = depth  * vfactor end
                            --
                            local xoffset = data.xoffset
                            local yoffset = data.yoffset
                            if xoffset then
                                xoffset = { "right", xoffset * hfactor }
                            end
                            if yoffset then
                                yoffset = { "down", -yoffset * vfactor }
                            end
                            if xoffset or yoffset then
                                local slot = { "slot", 1, addprivate(target,nil,fastcopy(character)) }
                                if xoffset and yoffset then
                                    character.commands = { xoffset, yoffset, slot }
                                elseif xoffset then
                                    character.commands = { xoffset, slot }
                                else
                                    character.commands = { yoffset, slot }
                                end
                                character.index = nil
                            end
                        elseif trace_defining then
                            report_math("no overloading dimensions of %C, not in font",unicode)
                        end
                    end
                end
                if set == nil then
                    set = { "default" }
                end
                if set == "all" or set == true then
                    for name, set in next, dimensions do
                        overload(set)
                    end
                else
                    if type(set) == "string" then
                        set = utilities.parsers.settings_to_array(set)
                    end
                    if type(set) == "table" then
                        for i=1,#set do
                            local d = dimensions[set[i]]
                            if d then
                                overload(d)
                            end
                        end
                    end
                end
            end
        end
    end
end

sequencers.appendaction("aftercopyingcharacters", "system","mathematics.overloaddimensions")

-- a couple of predefined tweaks:

local tweaks       = { }
mathematics.tweaks = tweaks

-- function tweaks.fixbadprime(target,original)
--     target.characters[0xFE325] = target.characters[0x2032]
-- end

-- these could go to math-fbk

-- local function accent_to_extensible(target,newchr,original,oldchr,height,depth,swap)
--     local characters = target.characters
--  -- if not characters[newchr] then -- xits needs an enforce
--     local addprivate = fonts.helpers.addprivate
--         local olddata = characters[oldchr]
--         if olddata then
--             if swap then
--                 swap = characters[swap]
--                 height = swap.depth
--                 depth  = 0
--             else
--                 height = height or 0
--                 depth  = depth  or 0
--             end
--             local correction = swap and { "down", (olddata.height or 0) - height } or { "down", olddata.height }
--             local newdata = {
--                 commands = { correction, { "slot", 1, oldchr } },
--                 width    = olddata.width,
--                 height   = height,
--                 depth    = depth,
--             }
--             characters[newchr] = newdata
--             local nextglyph = olddata.next
--             while nextglyph do
--                 local oldnextdata = characters[nextglyph]
--                 local newnextdata = {
--                     commands = { correction, { "slot", 1, nextglyph } },
--                     width    = oldnextdata.width,
--                     height   = height,
--                     depth    = depth,
--                 }
--                 local newnextglyph = addprivate(target,formatters["original-%H"](nextglyph),newnextdata)
--                 newdata.next = newnextglyph
--                 local nextnextglyph = oldnextdata.next
--                 if nextnextglyph == nextglyph then
--                     break
--                 else
--                     olddata   = oldnextdata
--                     newdata   = newnextdata
--                     nextglyph = nextnextglyph
--                 end
--             end
--             local hv = olddata.horiz_variants
--             if hv then
--                 hv = fastcopy(hv)
--                 newdata.horiz_variants = hv
--                 for i=1,#hv do
--                     local hvi = hv[i]
--                     local oldglyph = hvi.glyph
--                     local olddata = characters[oldglyph]
--                     local newdata = {
--                         commands = { correction, { "slot", 1, oldglyph } },
--                         width    = olddata.width,
--                         height   = height,
--                         depth    = depth,
--                     }
--                     hvi.glyph = addprivate(target,formatters["original-%H"](oldglyph),newdata)
--                 end
--             end
--         end
--  -- end
-- end

-- function tweaks.fixoverline(target,original)
--     local height, depth = 0, 0
--     local mathparameters = target.mathparameters
--     if mathparameters then
--         height = mathparameters.OverbarVerticalGap
--         depth  = mathparameters.UnderbarVerticalGap
--     else
--         height = target.parameters.xheight/4
--         depth  = height
--     end
--     accent_to_extensible(target,0x203E,original,0x0305,height,depth)
--     -- also crappy spacing for our purpose: push to top of baseline
--     accent_to_extensible(target,0xFE3DE,original,0x23DE,height,depth,0x23DF)
--     accent_to_extensible(target,0xFE3DC,original,0x23DC,height,depth,0x23DD)
--     accent_to_extensible(target,0xFE3B4,original,0x23B4,height,depth,0x23B5)
--     -- for symmetry
--     target.characters[0xFE3DF] = original.characters[0x23DF]
--     target.characters[0xFE3DD] = original.characters[0x23DD]
--     target.characters[0xFE3B5] = original.characters[0x23B5]
--  -- inspect(fonts.helpers.expandglyph(target.characters,0x203E))
--  -- inspect(fonts.helpers.expandglyph(target.characters,0x23DE))
-- end

-- sequencers.appendaction("aftercopyingcharacters", "system","mathematics.tweaks.fixoverline") -- for the moment always

-- helpers

local setmetatableindex  = table.setmetatableindex
local family_font        = node.family_font

local fontcharacters     = fonts.hashes.characters
local fontdescriptions   = fonts.hashes.descriptions
local extensibles        = utilities.storage.allocate()
fonts.hashes.extensibles = extensibles

local chardata           = characters.data
local extensibles        = mathematics.extensibles

-- we use numbers at the tex end (otherwise we could stick to chars)

local e_left       = extensibles.left
local e_right      = extensibles.right
local e_horizontal = extensibles.horizontal
local e_vertical   = extensibles.vertical
local e_mixed      = extensibles.mixed
local e_unknown    = extensibles.unknown

local unknown      = { e_unknown, false, false }

local function extensiblecode(font,unicode)
    local characters = fontcharacters[font]
    local character = characters[unicode]
    if not character then
        return unknown
    end
    local first = character.next
    local code = unicode
    local next = first
    while next do
        code = next
        character = characters[next]
        next = character.next
    end
    local char = chardata[unicode]
    if not char then
        return unknown
    end
    if character.horiz_variants then
        if character.vert_variants then
            return { e_mixed, code, character }
        else
            local m = char.mathextensible
            local e = m and extensibles[m]
            return e and { e, code, character } or unknown
        end
    elseif character.vert_variants then
        local m = char.mathextensible
        local e = m and extensibles[m]
        return e and { e, code, character } or unknown
    elseif first then
        -- assume accent (they seldom stretch .. sizes)
        local m = char.mathextensible or char.mathstretch
        local e = m and extensibles[m]
        return e and { e, code, character } or unknown
    else
        return unknown
    end
end

setmetatableindex(extensibles,function(extensibles,font)
    local codes = { }
    setmetatableindex(codes, function(codes,unicode)
        local status = extensiblecode(font,unicode)
        codes[unicode] = status
        return status
    end)
    extensibles[font] = codes
    return codes
end)

local function extensiblecode(family,unicode)
    return extensibles[family_font(family or 0)][unicode][1]
end

-- left       : [head] ...
-- right      : ... [head]
-- horizontal : [head] ... [head]
--
-- abs(right["start"] - right["end"]) | right.advance | characters[right.glyph].width

local function horizontalcode(family,unicode)
    local font    = family_font(family or 0)
    local data    = extensibles[font][unicode]
    local kind    = data[1]
    local loffset = 0
    local roffset = 0
    if kind == e_left then
        local charlist = data[3].horiz_variants
        if charlist then
            local left = charlist[1]
            loffset = abs((left["start"] or 0) - (left["end"] or 0))
        end
    elseif kind == e_right then
        local charlist = data[3].horiz_variants
        local right = charlist[#charlist]
        roffset = abs((right["start"] or 0) - (right["end"] or 0))
     elseif kind == e_horizontal then
        local charlist = data[3].horiz_variants
        if charlist then
            local left = charlist[1]
            local right = charlist[#charlist]
            loffset = abs((left ["start"] or 0) - (left ["end"] or 0))
            roffset = abs((right["start"] or 0) - (right["end"] or 0))
        end
    end
    return kind, loffset, roffset
end

mathematics.extensiblecode = extensiblecode
mathematics.horizontalcode = horizontalcode

interfaces.implement {
    name      = "extensiblecode",
    arguments = { "integer", "integer" },
    actions   = { extensiblecode, context }
}

interfaces.implement {
    name      = "horizontalcode",
    arguments = { "integer", "integer" },
    actions   = function(family,unicode)
        local kind, loffset, roffset = horizontalcode(family,unicode)
        texsetdimen("scratchleftoffset", loffset)
        texsetdimen("scratchrightoffset",roffset)
        context(kind)
    end
}

-- experiment

-- check: when true, only set when present in font
-- force: when false, then not set when already set

local blocks = characters.blocks -- this will move to char-ini

-- operators    : 0x02200
-- symbolsa     : 0x02701
-- symbolsb     : 0x02901
-- supplemental : 0x02A00

-- from mathematics.gaps:

blocks["lowercaseitalic"].gaps = {
    [0x1D455] = 0x0210E, -- ℎ h
}

blocks["uppercasescript"].gaps = {
    [0x1D49D] = 0x0212C, -- ℬ script B
    [0x1D4A0] = 0x02130, -- ℰ script E
    [0x1D4A1] = 0x02131, -- ℱ script F
    [0x1D4A3] = 0x0210B, -- ℋ script H
    [0x1D4A4] = 0x02110, -- ℐ script I
    [0x1D4A7] = 0x02112, -- ℒ script L
    [0x1D4A8] = 0x02133, -- ℳ script M
    [0x1D4AD] = 0x0211B, -- ℛ script R
}

blocks["lowercasescript"].gaps = {
    [0x1D4BA] = 0x0212F, -- ℯ script e
    [0x1D4BC] = 0x0210A, -- ℊ script g
    [0x1D4C4] = 0x02134, -- ℴ script o
}

blocks["uppercasefraktur"].gaps = {
    [0x1D506] = 0x0212D, -- ℭ fraktur C
    [0x1D50B] = 0x0210C, -- ℌ fraktur H
    [0x1D50C] = 0x02111, -- ℑ fraktur I
    [0x1D515] = 0x0211C, -- ℜ fraktur R
    [0x1D51D] = 0x02128, -- ℨ fraktur Z
}

blocks["uppercasedoublestruck"].gaps = {
    [0x1D53A] = 0x02102, -- ℂ bb C
    [0x1D53F] = 0x0210D, -- ℍ bb H
    [0x1D545] = 0x02115, -- ℕ bb N
    [0x1D547] = 0x02119, -- ℙ bb P
    [0x1D548] = 0x0211A, -- ℚ bb Q
    [0x1D549] = 0x0211D, -- ℝ bb R
    [0x1D551] = 0x02124, -- ℤ bb Z
}

-- todo: tounicode

function mathematics.injectfallbacks(target,original)
    local properties = original.properties
    if properties and properties.hasmath then
        local specification = target.specification
        if specification then
            local fallbacks = specification.fallbacks
            if fallbacks then
                local definitions = fonts.collections.definitions[fallbacks]
                if definitions then
                    if trace_collecting then
                        report_math("adding fallback characters to font %a",specification.hash)
                    end
                    local definedfont = fonts.definers.internal
                    local copiedglyph = fonts.handlers.vf.math.copy_glyph
                    local fonts       = target.fonts
                    local size        = specification.size -- target.size
                    local characters  = target.characters
                    if not fonts then
                        fonts = { }
                        target.fonts = fonts
                        target.type = "virtual"
                        target.properties.virtualized = true
                    end
                    if #fonts == 0 then
                        fonts[1] = { id = 0, size = size } -- sel, will be resolved later
                    end
                    local done = { }
                    for i=1,#definitions do
                        local definition = definitions[i]
                        local name   = definition.font
                        local start  = definition.start
                        local stop   = definition.stop
                        local gaps   = definition.gaps
                        local check  = definition.check
                        local force  = definition.force
                        local rscale = definition.rscale or 1
                        local offset = definition.offset or start
                        local id     = definedfont { name = name, size = size * rscale }
                        local index  = #fonts + 1
                        fonts[index] = { id = id, size = size }
                        local chars  = fontchars[id]
                        local function remap(unic,unicode,gap)
                            local unic = unicode + offset - start
                            if check and not chars[unicode] then
                                -- not in font
                            elseif force or (not done[unic] and not characters[unic]) then
                                if trace_collecting then
                                    report_math("remapping math character, vector %a, font %a, character %C%s%s",
                                        fallbacks,name,unic,check and ", checked",gap and ", gap plugged")
                                end
                                characters[unic] = copiedglyph(target,characters,chars,unicode,index)
                                done[unic] = true
                            end
                        end
                        for unicode = start, stop do
                            local unic = unicode + offset - start
                            remap(unic,unicode,false)
                        end
                        if gaps then
                            for unic, unicode in next, gaps do
                                remap(unic,unicode,true)
                            end
                        end
                    end
                end
            end
        end
    end
end

sequencers.appendaction("aftercopyingcharacters", "system","mathematics.injectfallbacks")