diff options
Diffstat (limited to 'tex/context/base/mkiv/typo-spa.lua')
| -rw-r--r-- | tex/context/base/mkiv/typo-spa.lua | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/tex/context/base/mkiv/typo-spa.lua b/tex/context/base/mkiv/typo-spa.lua new file mode 100644 index 000000000..519ba3f34 --- /dev/null +++ b/tex/context/base/mkiv/typo-spa.lua @@ -0,0 +1,259 @@ +if not modules then modules = { } end modules ['typo-spa'] = { + version = 1.001, + comment = "companion to typo-spa.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +local next, type = next, type +local utfchar = utf.char + +local trace_spacing = false trackers.register("typesetters.spacing", function(v) trace_spacing = v end) + +local report_spacing = logs.reporter("typesetting","spacing") + +local nodes, fonts, node = nodes, fonts, node + +local tasks = nodes.tasks + +local fonthashes = fonts.hashes +local fontdata = fonthashes.identifiers +local quaddata = fonthashes.quads + +local texsetattribute = tex.setattribute +local unsetvalue = attributes.unsetvalue + +local v_reset = interfaces.variables.reset + +local nuts = nodes.nuts +local tonut = nuts.tonut +local tonode = nuts.tonode + +local getnext = nuts.getnext +local getprev = nuts.getprev +local getchar = nuts.getchar +local getid = nuts.getid +local getfont = nuts.getfont +local getattr = nuts.getattr +local setattr = nuts.setattr + +local insert_node_before = nuts.insert_before +local insert_node_after = nuts.insert_after +local remove_node = nuts.remove +local end_of_math = nuts.end_of_math + +local nodepool = nuts.pool +local new_penalty = nodepool.penalty +local new_glue = nodepool.glue + +local nodecodes = nodes.nodecodes +local glyph_code = nodecodes.glyph +local math_code = nodecodes.math + +local somespace = nodes.somespace +local somepenalty = nodes.somepenalty + +typesetters = typesetters or { } +local typesetters = typesetters + +typesetters.spacings = typesetters.spacings or { } +local spacings = typesetters.spacings + +spacings.mapping = spacings.mapping or { } +spacings.numbers = spacings.numbers or { } + +local a_spacings = attributes.private("spacing") + +storage.register("typesetters/spacings/mapping", spacings.mapping, "typesetters.spacings.mapping") + +local mapping = spacings.mapping +local numbers = spacings.numbers + +for i=1,#mapping do + local m = mapping[i] + numbers[m.name] = m +end + +-- todo cache lastattr + +function spacings.handler(head) + head = tonut(head) + local done = false + local start = head + -- head is always begin of par (whatsit), so we have at least two prev nodes + -- penalty followed by glue + while start do + local id = getid(start) + if id == glyph_code then + local attr = getattr(start,a_spacings) + if attr and attr > 0 then + local data = mapping[attr] + if data then + local char = getchar(start) + local map = data.characters[char] + setattr(start,a_spacings,unsetvalue) -- needed? + if map then + local left = map.left + local right = map.right + local alternative = map.alternative + local quad = quaddata[getfont(start)] + local prev = getprev(start) + if left and left ~= 0 and prev then + local ok = false + local prevprev = getprev(prev) + if alternative == 1 then + local somespace = somespace(prev,true) + if somespace then + local somepenalty = somepenalty(prevprev,10000) + if somepenalty then + if trace_spacing then + report_spacing("removing penalty and space before %C (left)",char) + end + head = remove_node(head,prev,true) + head = remove_node(head,prevprev,true) + else + if trace_spacing then + report_spacing("removing space before %C (left)",char) + end + head = remove_node(head,prev,true) + end + end + ok = true + else + ok = not (somespace(prev,true) and somepenalty(prevprev,true)) or somespace(prev,true) + end + if ok then + if trace_spacing then + report_spacing("inserting penalty and space before %C (left)",char) + end + insert_node_before(head,start,new_penalty(10000)) + insert_node_before(head,start,new_glue(left*quad)) + done = true + end + end + local next = getnext(start) + if right and right ~= 0 and next then + local ok = false + local nextnext = getnext(next) + if alternative == 1 then + local somepenalty = somepenalty(next,10000) + if somepenalty then + local somespace = somespace(nextnext,true) + if somespace then + if trace_spacing then + report_spacing("removing penalty and space after %C right",char) + end + head = remove_node(head,next,true) + head = remove_node(head,nextnext,true) + end + else + local somespace = somespace(next,true) + if somespace then + if trace_spacing then + report_spacing("removing space after %C (right)", char) + end + head = remove_node(head,next,true) + end + end + ok = true + else + ok = not (somepenalty(next,10000) and somespace(nextnext,true)) or somespace(next,true) + end + if ok then + if trace_spacing then + report_spacing("inserting penalty and space after %C (right)",char) + end + insert_node_after(head,start,new_glue(right*quad)) + insert_node_after(head,start,new_penalty(10000)) + done = true + end + end + end + end + end + elseif id == math_code then + start = end_of_math(start) -- weird, can return nil .. no math end? + end + if start then + start = getnext(start) + end + end + return tonode(head), done +end + +local enabled = false + +function spacings.define(name) + local data = numbers[name] + if data then + -- error + else + local number = #mapping + 1 + local data = { + name = name, + number = number, + characters = { }, + } + mapping[number] = data + numbers[name] = data + end +end + +function spacings.setup(name,char,settings) + local data = numbers[name] + if not data then + -- error + else + data.characters[char] = settings + end +end + +function spacings.set(name) + local n = unsetvalue + if name ~= v_reset then + local data = numbers[name] + if data then + if not enabled then + tasks.enableaction("processors","typesetters.spacings.handler") + enabled = true + end + n = data.number or unsetvalue + end + end + texsetattribute(a_spacings,n) +end + +function spacings.reset() + texsetattribute(a_spacings,unsetvalue) +end + +-- interface + +local implement = interfaces.implement + +implement { + name = "definecharacterspacing", + actions = spacings.define, + arguments = "string" +} + +implement { + name = "setupcharacterspacing", + actions = spacings.setup, + arguments = { + "string", + "integer", + { + { "left", "number" }, + { "right", "number" }, + { "alternative", "integer" }, + } + } +} + +implement { + name = "setcharacterspacing", + actions = spacings.set, + arguments = "string" +} |