stable 2010-05-24 13:10

1 files changed, 897 insertions, 0 deletions

diff --git a/tex/context/base/mlib-pps.lua b/tex/context/base/mlib-pps.lua
new file mode 100644
index 000000000..8b36660d3
--- /dev/null
+++ b/tex/context/base/mlib-pps.lua
@@ -0,0 +1,897 @@
+if not modules then modules = { } end modules ['mlib-pps'] = { -- prescript, postscripts and specials
+    version   = 1.001,
+    comment   = "companion to mlib-ctx.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files",
+}
+
+-- current limitation: if we have textext as well as a special color then due to
+-- prescript/postscript overload we can have problems
+--
+-- todo: report max textexts
+
+local format, gmatch, concat, round, match = string.format, string.gmatch, table.concat, math.round, string.match
+local sprint = tex.sprint
+local tonumber, type = tonumber, type
+local lpegmatch = lpeg.match
+local texbox = tex.box
+local copy_list = node.copy_list
+
+local starttiming, stoptiming = statistics.starttiming, statistics.stoptiming
+
+local ctxcatcodes = tex.ctxcatcodes
+
+local trace_textexts = false  trackers.register("metapost.textexts", function(v) trace_textexts = v end)
+
+colors = colors or { }
+
+local rgbtocmyk  = colors.rgbtocmyk   or function() return 0,0,0,1 end
+local cmyktorgb  = colors.cmyktorgb   or function() return 0,0,0   end
+local rgbtogray  = colors.rgbtogray   or function() return 0       end
+local cmyktogray = colors.cmyktogray  or function() return 0       end
+
+metapost               = metapost or { }
+metapost.specials      = metapost.specials or { }
+metapost.specials.data = metapost.specials.data or { }
+metapost.externals     = metapost.externals or { n = 0 }
+
+local data = metapost.specials.data
+
+local colordata = { {}, {}, {}, {}, {} }
+
+--~ (r,g,b) => cmyk             : r=123 g=   1 b=hash
+--~         => spot             : r=123 g=   2 b=hash
+--~         => transparent rgb  : r=123 g=   3 b=hash
+--~         => transparent cmyk : r=123 g=   4 b=hash
+--~         => transparent spot : r=123 g=   5 b=hash
+--~         => rest             : r=123 g=n>10 b=whatever
+
+local nooutercolor        = "0 g 0 G"
+local nooutertransparency = "/Tr0 gs" -- only when set
+local outercolormode      = 0
+local outercolor          = nooutercolor
+local outertransparency   = nooutertransparency
+local innercolor          = nooutercolor
+local innertransparency   = nooutertransparency
+
+local pdfcolor, pdftransparency = lpdf.color, lpdf.transparency
+local registercolor, registerspotcolor = colors.register, colors.registerspotcolor
+local registertransparency = transparencies.register
+
+function metapost.set_outer_color(mode,colormodel,colorattribute,transparencyattribute)
+    -- has always to be called before conversion
+    -- todo: transparency (not in the mood now)
+    outercolormode = mode
+    if mode == 1 or mode == 3 then
+        -- inherit from outer (registered color)
+        outercolor        = pdfcolor(colormodel,colorattribute)    or nooutercolor
+        outertransparency = pdftransparency(transparencyattribute) or nooutertransparency
+    elseif mode == 2 then
+        -- stand alone (see m-punk.tex)
+        outercolor        = ""
+        outertransparency = ""
+    else -- 0
+        outercolor        = nooutercolor
+        outertransparency = nooutertransparency
+    end
+    innercolor        = outercolor
+    innertransparency = outertransparency -- not yet used
+end
+
+local function checked_color_pair(color)
+    if not color then
+        return innercolor, outercolor
+    elseif outercolormode == 3 then
+        innercolor = color
+        return innercolor, innercolor
+    else
+        return color, outercolor
+    end
+end
+
+metapost.checked_color_pair = checked_color_pair
+
+function metapost.colorinitializer()
+    innercolor = outercolor
+    innertransparency = outertransparency
+    return outercolor, outertransparency
+end
+
+function metapost.specials.register(str) -- only colors
+    local size, content, n, class = match(str,"^%%%%MetaPostSpecial: (%d+) (.*) (%d+) (%d+)$")
+    if class then
+        -- use lpeg splitter
+        local data = { }
+        for s in gmatch(content,"[^ ]+") do
+            data[#data+1] = s
+        end
+        class, n = tonumber(class), tonumber(n)
+        if class == 3 or class == 4 or class == 5 then
+            -- hm, weird
+        else
+            n = tonumber(data[1])
+        end
+        if n then
+            local cc = colordata[class]
+            if cc then
+                cc[n] = data
+            else
+                logs.report("mplib","problematic special: %s (no colordata class %s)", str or "?",class)
+            end
+        else
+         -- there is some bug to be solved, so we issue a message
+            logs.report("mplib","problematic special: %s", str or "?")
+        end
+    end
+--~     if match(str,"^%%%%MetaPostOption: multipass") then
+--~         metapost.multipass = true
+--~     end
+end
+
+local function spotcolorconverter(parent, n, d, p)
+    registerspotcolor(parent)
+    return pdfcolor(colors.model,registercolor(nil,'spot',parent,n,d,p))
+end
+
+function metapost.colorhandler(cs, object, result, colorconverter) -- handles specials
+    local cr = outercolor
+    local what = round(cs[2]*10000)
+    local data = colordata[what]
+    if data then
+        data = data[round(cs[3]*10000)]
+    end
+    if not data then
+        --
+    elseif what == 1 then
+        result[#result+1], cr = colorconverter({ data[2], data[3], data[4], data[5] })
+    elseif what == 2 then
+        result[#result+1] = spotcolorconverter(data[2],data[3],data[4],data[5])
+    else
+        if what == 3 then
+            result[#result+1], cr = colorconverter({ data[3], data[4], data[5]})
+        elseif what == 4 then
+            result[#result+1], cr = colorconverter({ data[3], data[4], data[5], data[6]})
+        elseif what == 5 then
+            result[#result+1] = spotcolorconverter(data[3],data[4],data[5],data[6])
+        end
+        object.prescript = "tr"
+        object.postscript = data[1] .. "," .. data[2]
+    end
+    object.color = nil
+    return object, cr
+end
+
+function metapost.colorspec(cs) -- used for shades ... returns table (for checking) or string (spot)
+    local what = round(cs[2]*10000)
+    local data = colordata[what][round(cs[3]*10000)]
+    if not data then
+        return { 0 }
+    elseif what == 1 then
+        return { tonumber(data[2]), tonumber(data[3]), tonumber(data[4]), tonumber(data[5]) }
+    elseif what == 2 then
+        return spotcolorconverter(data[2],data[3],data[4],data[5])
+    elseif what == 3 then
+        return { tonumber(data[3]), tonumber(data[4]), tonumber(data[5]) }
+    elseif what == 4 then
+        return { tonumber(data[3]), tonumber(data[4]), tonumber(data[5]), tonumber(data[6]) }
+    elseif what == 5 then
+        return spotcolorconverter(data[3],data[4],data[5],data[6])
+    end
+end
+
+function metapost.specials.tr(specification,object,result)
+    local a, t = match(specification,"^(.+),(.+)$")
+    local before = a and t and function()
+        result[#result+1] = format("/Tr%s gs",registertransparency(nil,a,t,true)) -- maybe nil instead of 'mp'
+        return object, result
+    end
+    local after = before and function()
+        result[#result+1] = outertransparency -- here we could revert to the outer color
+        return object, result
+    end
+    return object, before, nil, after
+end
+
+local specificationsplitter = lpeg.Ct(lpeg.splitat(" "))
+local colorsplitter         = lpeg.Ct(lpeg.splitat(":"))
+local colorsplitter         = lpeg.Ct(lpeg.splitter(":",tonumber))
+
+-- Unfortunately we cannot use cmyk colors natively because there is no
+-- generic color allocation primitive ... it's just an rgbcolor color.. This
+-- means that we cannot pass colors in either cmyk or rgb form.
+--
+-- def cmyk(expr c,m,y,k) =
+--     1 withprescript "cc" withpostscript ddddecimal (c,m,y,k)
+-- enddef ;
+--
+-- This is also an example of a simple plugin.
+
+--~ function metapost.specials.cc(specification,object,result)
+--~     object.color = lpegmatch(specificationsplitter,specification)
+--~     return object, nil, nil, nil
+--~ end
+--~ function metapost.specials.cc(specification,object,result)
+--~     local c = lpegmatch(specificationsplitter,specification)
+--~     local o = object.color[1]
+--~     c[1],c[2],c[3],c[4] = o*c[1],o*c[2],o*c[3],o*c[4]
+--~     return object, nil, nil, nil
+--~ end
+
+-- thanks to taco's reading of the postscript manual:
+--
+-- x' = sx * x + ry * y + tx
+-- y' = rx * x + sy * y + ty
+
+function metapost.specials.fg(specification,object,result,flusher) -- graphics
+    local op = object.path
+    local first, second, fourth  = op[1], op[2], op[4]
+    local tx, ty = first.x_coord      , first.y_coord
+    local sx, sy = second.x_coord - tx, fourth.y_coord - ty
+    local rx, ry = second.y_coord - ty, fourth.x_coord - tx
+    if sx == 0 then sx = 0.00001 end
+    if sy == 0 then sy = 0.00001 end
+    local before = specification and function()
+        flusher.flushfigure(result)
+        sprint(ctxcatcodes,format("\\MPLIBfigure{%f}{%f}{%f}{%f}{%f}{%f}{%s}",sx,rx,ry,sy,tx,ty,specification))
+        object.path = nil
+        return object, { }
+    end
+    return { } , before, nil, nil -- replace { } by object for tracing
+end
+
+function metapost.specials.ps(specification,object,result) -- positions
+    local op = object.path
+    local first, third  = op[1], op[3]
+    local x, y = first.x_coord, first.y_coord
+    local w, h = third.x_coord - x, third.y_coord - y
+    local label = specification
+    x = x - metapost.llx
+    y = metapost.ury - y
+ -- logs.report("mplib", "todo: position '%s' at (%s,%s) with (%s,%s)",label,x,y,w,h)
+    sprint(ctxcatcodes,format("\\dosavepositionwhd{%s}{0}{%sbp}{%sbp}{%sbp}{%sbp}{0pt}",label,x,y,w,h))
+    return { }, nil, nil, nil
+end
+
+local nofshades = 0 -- todo: hash resources, start at 1000 in order not to clash with older
+
+local function normalize(ca,cb)
+    if #cb == 1 then
+        if #ca == 4 then
+            cb[1], cb[2], cb[3], cb[4] = 0, 0, 0, 1-cb[1]
+        else
+            cb[1], cb[2], cb[3] = cb[1], cb[1], cb[1]
+        end
+    elseif #cb == 3 then
+        if #ca == 4 then
+            cb[1], cb[2], cb[3], cb[4] = rgbtocmyk(cb[1],cb[2],cb[3])
+        else
+            cb[1], cb[2], cb[3] = cmyktorgb(cb[1],cb[2],cb[3],cb[4])
+        end
+    end
+end
+
+-- todo: check for the same colorspace (actually a backend issue), now we can
+-- have several similar resources
+--
+-- normalize(ca,cb) fails for spotcolors
+
+function metapost.specials.cs(specification,object,result,flusher) -- spot colors?
+    -- a mess, not dynamic anyway
+    nofshades = nofshades + 1
+    flusher.flushfigure(result)
+    result = { }
+    local t = lpegmatch(specificationsplitter,specification)
+    -- we need a way to move/scale
+    local ca = lpegmatch(colorsplitter,t[4])
+    local cb = lpegmatch(colorsplitter,t[8])
+    if round(ca[1]*10000) == 123 then ca = metapost.colorspec(ca) end
+    if round(cb[1]*10000) == 123 then cb = metapost.colorspec(cb) end
+    local name = format("MplSh%s",nofshades)
+    local domain = { tonumber(t[1]), tonumber(t[2]) }
+    local coordinates = { tonumber(t[5]), tonumber(t[6]), tonumber(t[7]), tonumber(t[9]), tonumber(t[10]), tonumber(t[11]) }
+    if type(ca) == "string" then
+        -- backend specific (will be renamed)
+        lpdf.circularshade(name,domain,{ 0 },{ 1 },1,"DeviceGray",coordinates)
+    else
+        if #ca > #cb then
+            normalize(ca,cb)
+        elseif #ca < #cb then
+            normalize(cb,ca)
+        end
+        local model = colors.model
+        if model == "all" then
+            model= (#ca == 4 and "cmyk") or (#ca == 3 and "rgb") or "gray"
+        end
+        if model == "rgb" then
+            if #ca == 4 then
+                ca[1], ca[2], ca[3] = cmyktorgb(ca[1],ca[2],ca[3],ca[4])
+                cb[1], cb[2], cb[3] = cmyktorgb(cb[1],cb[2],cb[3],cb[4])
+                ca[4], cb[4] = nil, nil
+            elseif #ca == 1 then
+                local a, b = 1-ca[1], 1-cb[1]
+                ca[1], ca[2], ca[3] = a, a, a
+                cb[1], cb[2], cb[3] = b, b, b
+            end
+            -- backend specific (will be renamed)
+            lpdf.circularshade(name,domain,ca,cb,1,"DeviceRGB",coordinates)
+        elseif model == "cmyk" then
+            if #ca == 3 then
+                ca[1], ca[2], ca[3], ca[4] = rgbtocmyk(ca[1],ca[2],ca[3])
+                cb[1], cb[2], cb[3], ca[4] = rgbtocmyk(cb[1],cb[2],cb[3])
+            elseif #ca == 1 then
+                ca[1], ca[2], ca[3], ca[4] = 0, 0, 0, ca[1]
+                cb[1], cb[2], cb[3], ca[4] = 0, 0, 0, ca[1]
+            end
+            -- backend specific (will be renamed)
+            lpdf.circularshade(name,domain,ca,cb,1,"DeviceCMYK",coordinates)
+        else
+            if #ca == 4 then
+                ca[1] = cmyktogray(ca[1],ca[2],ca[3],ca[4])
+                cb[1] = cmyktogray(cb[1],cb[2],cb[3],cb[4])
+            elseif #ca == 3 then
+                ca[1] = rgbtogray(ca[1],ca[2],ca[3])
+                cb[1] = rgbtogray(cb[1],cb[2],cb[3])
+            end
+            -- backend specific (will be renamed)
+            lpdf.circularshade(name,domain,ca,cb,1,"DeviceGRAY",coordinates)
+        end
+    end
+    local before = function()
+        result[#result+1] = "q /Pattern cs"
+        return object, result
+    end
+    local after = function()
+        result[#result+1] = format("W n /%s sh Q", name)
+        return object, result
+    end
+    object.color, object.type = nil, nil
+    return object, before, nil, after
+end
+
+function metapost.specials.ls(specification,object,result,flusher)
+    nofshades = nofshades + 1
+    flusher.flushfigure(result)
+    result = { }
+    local t = lpegmatch(specificationsplitter,specification)
+    -- we need a way to move/scale
+    local ca = lpegmatch(colorsplitter,t[4])
+    local cb = lpegmatch(colorsplitter,t[7])
+    if round(ca[1]*10000) == 123 then ca = metapost.colorspec(ca) end
+    if round(cb[1]*10000) == 123 then cb = metapost.colorspec(cb) end
+    local name = format("MpSh%s",nofshades)
+    local domain = { tonumber(t[1]), tonumber(t[2]) }
+    local coordinates = { tonumber(t[5]), tonumber(t[6]), tonumber(t[8]), tonumber(t[9]) }
+    if type(ca) == "string" then
+        -- backend specific (will be renamed)
+        lpdf.linearshade(name,domain,{ 0 },{ 1 },1,"DeviceGray",coordinates)
+    else
+        if #ca > #cb then
+            normalize(ca,cb)
+        elseif #ca < #cb then
+            normalize(cb,ca)
+        end
+        local model = colors.model
+        if model == "all" then
+            model= (#ca == 4 and "cmyk") or (#ca == 3 and "rgb") or "gray"
+        end
+        if model == "rgb" then
+            if #ca == 4 then
+                ca[1], ca[2], ca[3] = cmyktorgb(ca[1],ca[2],ca[3],ca[4])
+                cb[1], cb[2], cb[3] = cmyktorgb(cb[1],cb[2],cb[3],cb[4])
+            elseif #ca == 1 then
+                local a, b = 1-ca[1], 1-cb[1]
+                ca[1], ca[2], ca[3] = a, a, a
+                cb[1], cb[2], cb[3] = b, b, b
+            end
+            -- backend specific (will be renamed)
+            lpdf.linearshade(name,domain,ca,cb,1,"DeviceRGB",coordinates)
+        elseif model == "cmyk" then
+            if #ca == 3 then
+                ca[1], ca[2], ca[3], ca[4] = rgbtocmyk(ca[1],ca[2],ca[3])
+                cb[1], cb[2], cb[3], ca[4] = rgbtocmyk(cb[1],cb[2],cb[3])
+            elseif #ca == 1 then
+                ca[1], ca[2], ca[3], ca[4] = 0, 0, 0, ca[1]
+                cb[1], cb[2], cb[3], ca[4] = 0, 0, 0, ca[1]
+            end
+            -- backend specific (will be renamed)
+            lpdf.linearshade(name,domain,ca,cb,1,"DeviceCMYK",coordinates)
+        else
+            if #ca == 4 then
+                ca[1] = cmyktogray(ca[1],ca[2],ca[3],ca[4])
+                cb[1] = cmyktogray(cb[1],cb[2],cb[3],cb[4])
+            elseif #ca == 3 then
+                ca[1] = rgbtogray(ca[1],ca[2],ca[3])
+                cb[1] = rgbtogray(cb[1],cb[2],cb[3])
+            end
+            -- backend specific (will be renamed)
+            lpdf.linearshade(name,domain,ca,cb,1,"DeviceGRAY",coordinates)
+        end
+    end
+    local before = function()
+        result[#result+1] = "q /Pattern cs"
+        return object, result
+    end
+    local after = function()
+        result[#result+1] = format("W n /%s sh Q", name)
+        return object, result
+    end
+    object.color, object.type = nil, nil
+    return object, before, nil, after
+end
+
+-- no need for a before here
+
+local current_format, current_graphic, current_initializations
+
+-- metapost.first_box       = metapost.first_box or 1000
+-- metapost.last_box        = metapost.last_box or 1100
+--~ metapost.textext_current = metapost.first_box
+metapost.multipass       = false
+
+local textexts = { }
+
+function metapost.free_boxes() -- todo: mp direct list ipv box
+ -- for i = metapost.first_box,metapost.last_box do
+ --     local b = texbox[i]
+ --     if b then
+ --         texbox[i] = nil -- no node.flush_list(b) needed, else double free error
+ --     else
+ --         break
+ --     end
+ -- end
+    for n, box in next, textexts do
+        local tn = textexts[n]
+        if tn then
+            -- somehow not flushed (used)
+            textexts[n] = nil
+        end
+    end
+    textexts = { }
+end
+
+function metapost.settext(box,slot)
+    textexts[slot] = copy_list(texbox[box])
+    texbox[box] = nil
+    -- this will become
+    -- textexts[slot] = texbox[box]
+    -- unsetbox(box)
+end
+
+function metapost.gettext(box,slot)
+    texbox[box] = copy_list(textexts[slot])
+--  textexts[slot] = nil -- no, pictures can be placed several times
+end
+
+function metapost.specials.tf(specification,object)
+--~ print("setting", metapost.textext_current)
+    local n, str = match(specification,"^(%d+):(.+)$")
+    if n and str then
+        n = tonumber(n)
+     -- if metapost.textext_current < metapost.last_box then
+     --     metapost.textext_current = metapost.first_box + n - 1
+     -- end
+        if trace_textexts then
+         -- logs.report("metapost","first pass: order %s, box %s",n,metapost.textext_current)
+            logs.report("metapost","first pass: order %s",n)
+        end
+     -- sprint(ctxcatcodes,format("\\MPLIBsettext{%s}{%s}",metapost.textext_current,str))
+        sprint(ctxcatcodes,format("\\MPLIBsettext{%s}{%s}",n,str))
+        metapost.multipass = true
+    end
+    return { }, nil, nil, nil
+end
+
+function metapost.specials.ts(specification,object,result,flusher)
+    -- print("getting", metapost.textext_current)
+    local n, str = match(specification,"^(%d+):(.+)$")
+    if n and str then
+        n = tonumber(n)
+        if trace_textexts then
+         -- logs.report("metapost","second pass: order %s, box %s",n,metapost.textext_current)
+            logs.report("metapost","second pass: order %s",n)
+        end
+        local op = object.path
+        local first, second, fourth = op[1], op[2], op[4]
+        local tx, ty = first.x_coord      , first.y_coord
+        local sx, sy = second.x_coord - tx, fourth.y_coord - ty
+        local rx, ry = second.y_coord - ty, fourth.x_coord - tx
+        if sx == 0 then sx = 0.00001 end
+        if sy == 0 then sy = 0.00001 end
+        if not trace_textexts then
+            object.path = nil
+        end
+        local before = function() -- no need for before function (just do it directly)
+        --~ flusher.flushfigure(result)
+        --~ sprint(ctxcatcodes,format("\\MPLIBgettext{%f}{%f}{%f}{%f}{%f}{%f}{%s}",sx,rx,ry,sy,tx,ty,metapost.textext_current))
+        --~ result = { }
+            result[#result+1] = format("q %f %f %f %f %f %f cm", sx,rx,ry,sy,tx,ty)
+            flusher.flushfigure(result)
+            -- if metapost.textext_current < metapost.last_box then
+            --     metapost.textext_current = metapost.first_box + n - 1
+            --  end
+         -- local b = metapost.textext_current
+         -- local box = texbox[b]
+            local box = textexts[n]
+            if box then
+             -- sprint(ctxcatcodes,format("\\MPLIBgettextscaled{%s}{%s}{%s}",b,metapost.sxsy(box.width,box.height,box.depth)))
+                sprint(ctxcatcodes,format("\\MPLIBgettextscaled{%s}{%s}{%s}",n,metapost.sxsy(box.width,box.height,box.depth)))
+            else
+                -- error
+            end
+            result = { "Q" }
+            return object, result
+        end
+        return { }, before, nil, nil -- replace { } by object for tracing
+    else
+        return { }, nil, nil, nil -- replace { } by object for tracing
+    end
+end
+
+-- rather generic pdf, so use this elsewhere too it no longer pays
+-- off to distinguish between outline and fill (we now have both
+-- too, e.g. in arrows)
+
+metapost.reducetogray = true
+
+local models = { }
+
+function models.all(cr)
+    local n = #cr
+    if n == 0 then
+        return checked_color_pair()
+    elseif metapost.reducetogray then
+        if n == 1 then
+            local s = cr[1]
+            return checked_color_pair(format("%.3f g %.3f G",s,s))
+        elseif n == 3 then
+            local r, g, b = cr[1], cr[2], cr[3]
+            if r == g and g == b then
+                return checked_color_pair(format("%.3f g %.3f G",r,r))
+            else
+                return checked_color_pair(format("%.3f %.3f %.3f rg %.3f %.3f %.3f RG",r,g,b,r,g,b))
+            end
+        else
+            local c, m, y, k = cr[1], cr[2], cr[3], cr[4]
+            if c == m and m == y and y == 0 then
+                k = 1 - k
+                return checked_color_pair(format("%.3f g %.3f G",k,k))
+            else
+                return checked_color_pair(format("%.3f %.3f %.3f %.3f k %.3f %.3f %.3f %.3f K",c,m,y,k,c,m,y,k))
+            end
+        end
+    elseif n == 1 then
+        local s = cr[1]
+        return checked_color_pair(format("%.3f g %.3f G",s,s))
+    elseif n == 3 then
+        local r, g, b = cr[1], cr[2], cr[3]
+        return checked_color_pair(format("%.3f %.3f %.3f rg %.3f %.3f %.3f RG",r,g,b,r,g,b))
+    else
+        local c, m, y, k = cr[1], cr[2], cr[3], cr[4]
+        return checked_color_pair(format("%.3f %.3f %.3f %.3f k %.3f %.3f %.3f %.3f K",c,m,y,k,c,m,y,k))
+    end
+end
+
+function models.rgb(cr)
+    local n = #cr
+    if n == 0 then
+        return checked_color_pair()
+    elseif metapost.reducetogray then
+        if n == 1 then
+            local s = cr[1]
+            checked_color_pair(format("%.3f g %.3f G",s,s))
+        elseif n == 3 then
+            local r, g, b = cr[1], cr[2], cr[3]
+            if r == g and g == b then
+                return checked_color_pair(format("%.3f g %.3f G",r,r))
+            else
+                return checked_color_pair(format("%.3f %.3f %.3f rg %.3f %.3f %.3f RG",r,g,b,r,g,b))
+            end
+        else
+            local c, m, y, k = cr[1], cr[2], cr[3], cr[4]
+            if c == m and m == y and y == 0 then
+                k = 1 - k
+                return checked_color_pair(format("%.3f g %.3f G",k,k))
+            else
+                local r, g, b = cmyktorgb(c,m,y,k)
+                return checked_color_pair(format("%.3f %.3f %.3f rg %.3f %.3f %.3f RG",r,g,b,r,g,b))
+            end
+        end
+    elseif n == 1 then
+        local s = cr[1]
+        return checked_color_pair(format("%.3f g %.3f G",s,s))
+    else
+        local r, g, b
+        if n == 3 then
+            r, g, b = cmyktorgb(cr[1],cr[2],cr[3],cr[4])
+        else
+            r, g, b = cr[1], cr[2], cr[3]
+        end
+        return checked_color_pair(format("%.3f %.3f %.3f rg %.3f %.3f %.3f RG",r,g,b,r,g,b))
+    end
+end
+
+function models.cmyk(cr)
+    local n = #cr
+    if n == 0 then
+        return checked_color_pair()
+    elseif metapost.reducetogray then
+        if n == 1 then
+            local s = cr[1]
+            return checked_color_pair(format("%.3f g %.3f G",s,s))
+        elseif n == 3 then
+            local r, g, b = cr[1], cr[2], cr[3]
+            if r == g and g == b then
+                return checked_color_pair(format("%.3f g %.3f G",r,r))
+            else
+                local c, m, y, k = rgbtocmyk(r,g,b)
+                return checked_color_pair(format("%.3f %.3f %.3f %.3f k %.3f %.3f %.3f %.3f K",c,m,y,k,c,m,y,k))
+            end
+        else
+            local c, m, y, k = cr[1], cr[2], cr[3], cr[4]
+            if c == m and m == y and y == 0 then
+                k = 1 - k
+                return checked_color_pair(format("%.3f g %.3f G",k,k))
+            else
+                return checked_color_pair(format("%.3f %.3f %.3f %.3f k %.3f %.3f %.3f %.3f K",c,m,y,k,c,m,y,k))
+            end
+        end
+    elseif n == 1 then
+        local s = cr[1]
+        return checked_color_pair(format("%.3f g %.3f G",s,s))
+    else
+        local c, m, y, k
+        if n == 3 then
+            c, m, y, k = rgbtocmyk(cr[1],cr[2],cr[3])
+        else
+            c, m, y, k = cr[1], cr[2], cr[3], cr[4]
+        end
+        return checked_color_pair(format("%.3f %.3f %.3f %.3f k %.3f %.3f %.3f %.3f K",c,m,y,k,c,m,y,k))
+    end
+end
+
+function models.gray(cr)
+    local n, s = #cr, 0
+    if n == 0 then
+        return checked_color_pair()
+    elseif n == 4 then
+        s = cmyktogray(cr[1],cr[2],cr[3],cr[4])
+    elseif n == 3 then
+        s = rgbtogray(cr[1],cr[2],cr[3])
+    else
+        s = cr[1]
+    end
+    return checked_color_pair(format("%.3f g %.3f G",s,s))
+end
+
+function metapost.colorconverter()
+    return models[colors.model] or gray
+end
+
+do
+
+    local P, S, V, Cs = lpeg.P, lpeg.S, lpeg.V, lpeg.Cs
+
+    local btex      = P("btex")
+    local etex      = P(" etex")
+    local vtex      = P("verbatimtex")
+    local ttex      = P("textext")
+    local gtex      = P("graphictext")
+    local multipass = P("forcemultipass")
+    local spacing   = S(" \n\r\t\v")^0
+    local dquote    = P('"')
+
+    local found, forced = false, false
+
+    local function convert(str)
+        found = true
+        return "rawtextext(\"" .. str .. "\")" -- centered
+    end
+    local function ditto(str)
+        return "\" & ditto & \""
+    end
+    local function register()
+        found = true
+    end
+    local function force()
+        forced = true
+    end
+
+    local texmess   = (dquote/ditto + (1 - etex))^0
+
+    local function ignore(s)
+        logs.report("mplib","ignoring verbatim tex: %s",s)
+        return ""
+    end
+
+    local parser = P {
+        [1] = Cs((V(2)/register + V(4)/ignore + V(3)/convert + V(5)/force + 1)^0),
+        [2] = ttex + gtex,
+        [3] = btex * spacing * Cs(texmess) * etex,
+        [4] = vtex * spacing * Cs(texmess) * etex,
+        [5] = multipass, -- experimental, only for testing
+    }
+
+    -- currently a a one-liner produces less code
+
+    local parser = Cs((
+        (ttex + gtex)/register
+      + (btex * spacing * Cs(texmess) * etex)/convert
+      + (vtex * spacing * Cs(texmess) * etex)/ignore
+      + 1
+    )^0)
+
+    function metapost.check_texts(str)
+        found, forced = false, false
+        return lpegmatch(parser,str), found, forced
+    end
+
+end
+
+local factor = 65536*(7227/7200)
+
+function metapost.edefsxsy(wd,ht,dp) -- helper for figure
+    local hd = ht + dp
+    commands.edef("sx",(wd ~= 0 and factor/wd) or 0)
+    commands.edef("sy",(hd ~= 0 and factor/hd) or 0)
+end
+
+function metapost.sxsy(wd,ht,dp) -- helper for text
+    local hd = ht + dp
+    return (wd ~= 0 and factor/wd) or 0, (hd ~= 0 and factor/hd) or 0
+end
+
+local no_trial_run       = "_trial_run_ := false ;"
+local do_trial_run       = "if unknown _trial_run_ : boolean _trial_run_ fi ; _trial_run_ := true ;"
+local text_data_template = "_tt_w_[%i]:=%f;_tt_h_[%i]:=%f;_tt_d_[%i]:=%f;"
+local do_begin_fig       = "; beginfig(1); "
+local do_end_fig         = "; endfig ;"
+local do_safeguard       = ";"
+
+function metapost.text_texts_data()
+    local t, n = { }, 0
+--~     for i = metapost.first_box, metapost.last_box do
+--~         n = n + 1
+--~         local box = texbox[i]
+    for n, box in next, textexts do
+        if trace_textexts then
+            logs.report("metapost","passed data: order %s, box %s",n,i)
+        end
+        if box then
+            t[#t+1] = format(text_data_template,n,box.width/factor,n,box.height/factor,n,box.depth/factor)
+        else
+            break
+        end
+    end
+--~     print(table.serialize(t))
+    return t
+end
+
+metapost.intermediate         = metapost.intermediate         or {}
+metapost.intermediate.actions = metapost.intermediate.actions or {}
+metapost.intermediate.needed  = false
+
+metapost.method = 1 -- 1:dumb 2:clever
+
+function metapost.graphic_base_pass(mpsformat,str,initializations,preamble,askedfig)
+    local nofig = (askedfig and "") or false
+    local done_1, done_2, forced_1, forced_2
+    str, done_1, forced_1 = metapost.check_texts(str)
+    if not preamble or preamble == "" then
+        preamble, done_2, forced_2 = "", false, false
+    else
+        preamble, done_2, forced_2 = metapost.check_texts(preamble)
+    end
+ -- metapost.textext_current = metapost.first_box
+    metapost.intermediate.needed  = false
+    metapost.multipass = false -- no needed here
+    current_format, current_graphic, current_initializations = mpsformat, str, initializations or ""
+    if metapost.method == 1 or (metapost.method == 2 and (done_1 or done_2)) then
+     -- first true means: trialrun, second true means: avoid extra run if no multipass
+        local flushed = metapost.process(mpsformat, {
+            preamble,
+            nofig or do_begin_fig,
+            do_trial_run,
+            current_initializations,
+            do_safeguard,
+            current_graphic,
+            nofig or do_end_fig
+     -- }, true, nil, true )
+        }, true, nil, not (forced_1 or forced_2), false, askedfig)
+        if metapost.intermediate.needed then
+            for _, action in next, metapost.intermediate.actions do
+                action()
+            end
+        end
+        if not flushed or not metapost.optimize then
+            -- tricky, we can only ask once for objects and therefore
+            -- we really need a second run when not optimized
+            sprint(ctxcatcodes,format("\\ctxlua{metapost.graphic_extra_pass(%s)}",askedfig or "false"))
+        end
+    else
+        metapost.process(mpsformat, {
+            preamble,
+            nofig or do_begin_fig,
+            no_trial_run,
+            current_initializations,
+            do_safeguard,
+            current_graphic,
+            nofig or do_end_fig
+        }, false, nil, false, false, askedfig )
+    end
+    -- here we could free the textext boxes
+    metapost.free_boxes()
+end
+
+function metapost.graphic_extra_pass(askedfig)
+    local nofig = (askedfig and "") or false
+ -- metapost.textext_current = metapost.first_box
+    metapost.process(current_format, {
+        nofig or do_begin_fig,
+        no_trial_run,
+        concat(metapost.text_texts_data()," ;\n"),
+        current_initializations,
+        do_safeguard,
+        current_graphic,
+        nofig or do_end_fig
+    }, false, nil, false, true, askedfig )
+end
+
+metapost.tex = metapost.tex or { }
+
+do -- only used in graphictexts
+
+    local environments = { }
+
+    function metapost.tex.set(str)
+        environments[#environments+1] = str
+    end
+    function metapost.tex.reset()
+        environments = { }
+    end
+    function metapost.tex.get()
+        return concat(environments,"\n")
+    end
+
+end
+
+local graphics = { }
+local start    = [[\starttext]]
+local preamble = [[\long\def\MPLIBgraphictext#1{\startTEXpage[scale=10000]#1\stopTEXpage}]]
+local stop     = [[\stoptext]]
+
+function metapost.specials.gt(specification,object) -- number, so that we can reorder
+    graphics[#graphics+1] = format("\\MPLIBgraphictext{%s}",specification)
+    metapost.intermediate.needed = true
+    metapost.multipass = true
+    return { }, nil, nil, nil
+end
+
+function metapost.intermediate.actions.makempy()
+    if #graphics > 0 then
+        local externals = metapost.externals
+        externals.n = externals.n + 1
+        starttiming(externals)
+        local mpofile = tex.jobname .. "-mpgraph"
+        local mpyfile = file.replacesuffix(mpofile,"mpy")
+        local pdffile = file.replacesuffix(mpofile,"pdf")
+        local texfile = file.replacesuffix(mpofile,"tex")
+        io.savedata(texfile, { start, preamble, metapost.tex.get(), concat(graphics,"\n"), stop }, "\n")
+        local command = format("context --once %s %s", (tex.interactionmode == 0 and "--batchmode") or "", texfile)
+        os.execute(command)
+        if io.exists(pdffile) then
+            command = format("pstoedit -ssp -dt -f mpost %s %s", pdffile, mpyfile)
+            os.execute(command)
+            local result = { }
+            if io.exists(mpyfile) then
+                local data = io.loaddata(mpyfile)
+                for figure in gmatch(data,"beginfig(.-)endfig") do
+                    result[#result+1] = format("begingraphictextfig%sendgraphictextfig ;\n", figure)
+                end
+                io.savedata(mpyfile,concat(result,""))
+            end
+        end
+        stoptiming(externals)
+        graphics = { } -- ?
+    end
+end