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authorKhaled Hosny <khaledhosny@eglug.org>2010-05-10 17:23:06 +0300
committerKhaled Hosny <khaledhosny@eglug.org>2010-05-10 17:23:06 +0300
commit7002dfe5556f503320d9bee480e5fb43bdb6e7a3 (patch)
tree384ee73556657b6818c78b006cfa625776c980cd /luaextra-dimen.lua
parent20864d5fdb81f248500f2e94c95b3b15569cc277 (diff)
downloadlualibs-7002dfe5556f503320d9bee480e5fb43bdb6e7a3.tar.gz
Rename to lualibs
Rename luaextra->lualibs when sensible, also use luatexbase instead of luatextra.
Diffstat (limited to 'luaextra-dimen.lua')
-rw-r--r--luaextra-dimen.lua428
1 files changed, 0 insertions, 428 deletions
diff --git a/luaextra-dimen.lua b/luaextra-dimen.lua
deleted file mode 100644
index a8faa27..0000000
--- a/luaextra-dimen.lua
+++ /dev/null
@@ -1,428 +0,0 @@
-if not modules then modules = { } end modules ['l-dimen'] = {
- version = 1.001,
- comment = "support for dimensions",
- author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
- copyright = "PRAGMA ADE / ConTeXt Development Team",
- license = "see context related readme files"
-}
-
---[[ldx--
-<p>Internally <l n='luatex'/> work with scaled point, which are
-represented by integers. However, in practice, at east at the
-<l n='tex'/> end we work with more generic units like points (pt). Going
-from scaled points (numbers) to one of those units can be
-done by using the conversion factors collected in the following
-table.</p>
---ldx]]--
-
-local format, match, gsub, type, setmetatable = string.format, string.match, string.gsub, type, setmetatable
-local P, S, R, Cc, lpegmatch = lpeg.P, lpeg.S, lpeg.R, lpeg.Cc, lpeg.match
-
-number = number or { }
-
-number.tonumberf = function(n) return match(format("%.20f",n),"(.-0?)0*$") end -- one zero too much but alas
-number.tonumberg = function(n) return format("%.20g",n) end
-
-local dimenfactors = {
- ["pt"] = 1/65536,
- ["in"] = ( 100/ 7227)/65536,
- ["cm"] = ( 254/ 7227)/65536,
- ["mm"] = ( 2540/ 7227)/65536,
- ["sp"] = 1, -- 65536 sp in 1pt
- ["bp"] = ( 7200/ 7227)/65536,
- ["pc"] = ( 1/ 12)/65536,
- ["dd"] = ( 1157/ 1238)/65536,
- ["cc"] = ( 1157/14856)/65536,
- ["nd"] = (20320/21681)/65536,
- ["nc"] = ( 5080/65043)/65536
-}
-
---~ print(table.serialize(dimenfactors))
---~
---~ %.99g:
---~
---~ t={
---~ ["bp"]=1.5201782378580324e-005,
---~ ["cc"]=1.1883696112892098e-006,
---~ ["cm"]=5.3628510057769479e-007,
---~ ["dd"]=1.4260435335470516e-005,
---~ ["em"]=0.000152587890625,
---~ ["ex"]=6.103515625e-005,
---~ ["in"]=2.1113586636917117e-007,
---~ ["mm"]=5.3628510057769473e-008,
---~ ["nc"]=1.1917446679504327e-006,
---~ ["nd"]=1.4300936015405194e-005,
---~ ["pc"]=1.2715657552083333e-006,
---~ ["pt"]=1.52587890625e-005,
---~ ["sp"]=1,
---~ }
---~
---~ patched %s and tonumber
---~
---~ t={
---~ ["bp"]=0.00001520178238,
---~ ["cc"]=0.00000118836961,
---~ ["cm"]=0.0000005362851,
---~ ["dd"]=0.00001426043534,
---~ ["em"]=0.00015258789063,
---~ ["ex"]=0.00006103515625,
---~ ["in"]=0.00000021113587,
---~ ["mm"]=0.00000005362851,
---~ ["nc"]=0.00000119174467,
---~ ["nd"]=0.00001430093602,
---~ ["pc"]=0.00000127156576,
---~ ["pt"]=0.00001525878906,
---~ ["sp"]=1,
---~ }
-
---[[ldx--
-<p>A conversion function that takes a number, unit (string) and optional
-format (string) is implemented using this table.</p>
---ldx]]--
-
--- was:
-
-local function todimen(n,unit,fmt)
- if type(n) == 'string' then
- return n
- else
- unit = unit or 'pt'
- return format(fmt or "%s%s",n*dimenfactors[unit],unit)
- -- if fmt then
- -- return format(fmt,n*dimenfactors[unit],unit)
- -- else
- -- return match(format("%.20f",n*dimenfactors[unit]),"(.-0?)0*$") .. unit
- -- end
- end
-end
-
---[[ldx--
-<p>We collect a bunch of converters in the <type>number</type> namespace.</p>
---ldx]]--
-
-number.maxdimen = 1073741823
-number.todimen = todimen
-number.dimenfactors = dimenfactors
-
-function number.topoints (n) return todimen(n,"pt") end
-function number.toinches (n) return todimen(n,"in") end
-function number.tocentimeters (n) return todimen(n,"cm") end
-function number.tomillimeters (n) return todimen(n,"mm") end
-function number.toscaledpoints(n) return todimen(n,"sp") end
-function number.toscaledpoints(n) return n .. "sp" end
-function number.tobasepoints (n) return todimen(n,"bp") end
-function number.topicas (n) return todimen(n "pc") end
-function number.todidots (n) return todimen(n,"dd") end
-function number.tociceros (n) return todimen(n,"cc") end
-function number.tonewdidots (n) return todimen(n,"nd") end
-function number.tonewciceros (n) return todimen(n,"nc") end
-
---[[ldx--
-<p>More interesting it to implement a (sort of) dimen datatype, one
-that permits calculations too. First we define a function that
-converts a string to scaledpoints. We use <l n='lpeg'/>. We capture
-a number and optionally a unit. When no unit is given a constant
-capture takes place.</p>
---ldx]]--
-
-local amount = (S("+-")^0 * R("09")^0 * P(".")^0 * R("09")^0) + Cc("0")
-local unit = R("az")^1
-
-local pattern = amount/tonumber * (unit^1/dimenfactors + Cc(1)) -- tonumber is new
-
-lpeg.patterns.dimenpair = pattern
-
---[[ldx--
-<p>We use a metatable to intercept errors. When no key is found in
-the table with factors, the metatable will be consulted for an
-alternative index function.</p>
---ldx]]--
-
-local mt = { } setmetatable(dimenfactors,mt)
-
-mt.__index = function(t,s)
- -- error("wrong dimension: " .. (s or "?")) -- better a message
- return false
-end
-
-function string:todimen()
- if type(self) == "number" then
- return self
- else
- local value, unit = lpegmatch(pattern,self)
- return value/unit
- end
-end
-
-local amount = S("+-")^0 * R("09")^0 * S(".,")^0 * R("09")^0
-local unit = P("pt") + P("cm") + P("mm") + P("sp") + P("bp") + P("in") +
- P("pc") + P("dd") + P("cc") + P("nd") + P("nc")
-
-local pattern = amount * unit
-
-lpeg.patterns.validdimen = pattern
-
---[[ldx--
-<p>This converter accepts calls like:</p>
-
-<typing>
-string.todimen("10"))
-string.todimen(".10"))
-string.todimen("10.0"))
-string.todimen("10.0pt"))
-string.todimen("10pt"))
-string.todimen("10.0pt"))
-</typing>
-
-<p>And of course the often more efficient:</p>
-
-<typing>
-somestring:todimen("12.3cm")
-</typing>
-
-<p>With this in place, we can now implement a proper datatype for dimensions, one
-that permits us to do this:</p>
-
-<typing>
-s = dimen "10pt" + dimen "20pt" + dimen "200pt"
- - dimen "100sp" / 10 + "20pt" + "0pt"
-</typing>
-
-<p>We create a local metatable for this new type:</p>
---ldx]]--
-
-local dimensions = { }
-
---[[ldx--
-<p>The main (and globally) visible representation of a dimen is defined next: it is
-a one-element table. The unit that is returned from the match is normally a number
-(one of the previously defined factors) but we also accept functions. Later we will
-see why.</p>
---ldx]]--
-
-function dimen(a)
- if a then
- local ta= type(a)
- if ta == "string" then
- local value, unit = lpegmatch(pattern,a)
- if type(unit) == "function" then
- k = value/unit()
- else
- k = value/unit
- end
- a = k
- elseif ta == "table" then
- a = a[1]
- end
- return setmetatable({ a }, dimensions)
- else
- return setmetatable({ 0 }, dimensions)
- end
-end
-
---[[ldx--
-<p>This function return a small hash with a metatable attached. It is
-through this metatable that we can do the calculations. We could have
-shared some of the code but for reasons of speed we don't.</p>
---ldx]]--
-
-function dimensions.__add(a, b)
- local ta, tb = type(a), type(b)
- if ta == "string" then a = a:todimen() elseif ta == "table" then a = a[1] end
- if tb == "string" then b = b:todimen() elseif tb == "table" then b = b[1] end
- return setmetatable({ a + b }, dimensions)
-end
-
-function dimensions.__sub(a, b)
- local ta, tb = type(a), type(b)
- if ta == "string" then a = a:todimen() elseif ta == "table" then a = a[1] end
- if tb == "string" then b = b:todimen() elseif tb == "table" then b = b[1] end
- return setmetatable({ a - b }, dimensions)
-end
-
-function dimensions.__mul(a, b)
- local ta, tb = type(a), type(b)
- if ta == "string" then a = a:todimen() elseif ta == "table" then a = a[1] end
- if tb == "string" then b = b:todimen() elseif tb == "table" then b = b[1] end
- return setmetatable({ a * b }, dimensions)
-end
-
-function dimensions.__div(a, b)
- local ta, tb = type(a), type(b)
- if ta == "string" then a = a:todimen() elseif ta == "table" then a = a[1] end
- if tb == "string" then b = b:todimen() elseif tb == "table" then b = b[1] end
- return setmetatable({ a / b }, dimensions)
-end
-
-function dimensions.__unm(a)
- local ta = type(a)
- if ta == "string" then a = a:todimen() elseif ta == "table" then a = a[1] end
- return setmetatable({ - a }, dimensions)
-end
-
---[[ldx--
-<p>It makes no sense to implement the power and modulo function but
-the next two do make sense because they permits is code like:</p>
-
-<typing>
-local a, b = dimen "10pt", dimen "11pt"
-...
-if a > b then
- ...
-end
-</typing>
---ldx]]--
-
--- makes no sense: dimensions.__pow and dimensions.__mod
-
-function dimensions.__lt(a, b)
- return a[1] < b[1]
-end
-
-function dimensions.__eq(a, b)
- return a[1] == b[1]
-end
-
---[[ldx--
-<p>We also need to provide a function for conversion to string (so that
-we can print dimensions). We print them as points, just like <l n='tex'/>.</p>
---ldx]]--
-
-function dimensions.__tostring(a)
- return a[1]/65536 .. "pt" -- instead of todimen(a[1])
-end
-
---[[ldx--
-<p>Since it does not take much code, we also provide a way to access
-a few accessors</p>
-
-<typing>
-print(dimen().pt)
-print(dimen().sp)
-</typing>
---ldx]]--
-
-function dimensions.__index(tab,key)
- local d = dimenfactors[key]
- if not d then
- error("illegal property of dimen: " .. key)
- d = 1
- end
- return 1/d
-end
-
---[[ldx--
-<p>In the converter from string to dimension we support functions as
-factors. This is because in <l n='tex'/> we have a few more units:
-<type>ex</type> and <type>em</type>. These are not constant factors but
-depend on the current font. They are not defined by default, but need
-an explicit function call. This is because at the moment that this code
-is loaded, the relevant tables that hold the functions needed may not
-yet be available.</p>
---ldx]]--
-
-function dimensions.texify() -- todo: %
- local fti, fc = fonts and fonts.ids and fonts.ids, font and font.current
- if fti and fc then
- dimenfactors["ex"] = function() return fti[fc()].ex_height end
- dimenfactors["em"] = function() return fti[fc()].quad end
- else
- dimenfactors["ex"] = 1/65536* 4 -- 4pt
- dimenfactors["em"] = 1/65536*10 -- 10pt
- end
-end
-
---[[ldx--
-<p>In order to set the defaults we call this function now. At some point
-the macro package needs to make sure the function is called again.</p>
---ldx]]--
-
-dimensions.texify()
-
---[[ldx--
-<p>The previous code is rather efficient (also thanks to <l n='lpeg'/>) but we
-can speed it up by caching converted dimensions. On my machine (2008) the following
-loop takes about 25.5 seconds.</p>
-
-<typing>
-for i=1,1000000 do
- local s = dimen "10pt" + dimen "20pt" + dimen "200pt"
- - dimen "100sp" / 10 + "20pt" + "0pt"
-end
-</typing>
-
-<p>When we cache converted strings this becomes 16.3 seconds. In order not
-to waste too much memory on it, we tag the values of the cache as being
-week which mean that the garbage collector will collect them in a next
-sweep. This means that in most cases the speed up is mostly affecting the
-current couple of calculations and as such the speed penalty is small.</p>
-
-<p>We redefine two previous defined functions that can benefit from
-this:</p>
---ldx]]--
-
-local known = { } setmetatable(known, { __mode = "v" })
-
-function dimen(a)
- if a then
- local ta= type(a)
- if ta == "string" then
- local k = known[a]
- if k then
- a = k
- else
- local value, unit = lpegmatch(pattern,a)
- if type(unit) == "function" then
- k = value/unit()
- else
- k = value/unit
- end
- known[a] = k
- a = k
- end
- elseif ta == "table" then
- a = a[1]
- end
- return setmetatable({ a }, dimensions)
- else
- return setmetatable({ 0 }, dimensions)
- end
-end
-
-function string:todimen()
- if type(self) == "number" then
- return self
- else
- local k = known[self]
- if not k then
- local value, unit = lpegmatch(pattern,self)
- if value and unit then
- k = value/unit
- else
- k = 0
- end
- -- print(self,value,unit)
- known[self] = k
- end
- return k
- end
-end
-
---[[ldx--
-<p>In a similar fashion we can define a glue datatype. In that case we
-probably use a hash instead of a one-element table.</p>
---ldx]]--
-
---[[ldx--
-<p>Goodie:s</p>
---ldx]]--
-
-function number.percent(n) -- will be cleaned up once luatex 0.30 is out
- local hsize = tex.hsize
- if type(hsize) == "string" then
- hsize = hsize:todimen()
- end
- return (n/100) * hsize
-end
-
-number["%"] = number.percent