context, from www.pragma-ade.com/context/beta/cont-tmf.zip (18apr15)

git-svn-id: svn://tug.org/texlive/trunk@36923 c570f23f-e606-0410-a88d-b1316a301751

11 files changed, 1032 insertions, 455 deletions

diff --git a/Master/texmf-dist/metapost/context/base/metafun.mpiv b/Master/texmf-dist/metapost/context/base/metafun.mpiv
index 095b84b0ecc..b1d4f32e7ee 100644
--- a/Master/texmf-dist/metapost/context/base/metafun.mpiv
+++ b/Master/texmf-dist/metapost/context/base/metafun.mpiv
@@ -15,6 +15,9 @@
 %D prevent dependency problems and in the end even may use a patched version,
 %D we prefer to use a copy.
 
+prologues := 0 ;
+mpprocset := 1 ;
+
 input "mp-base.mpiv" ;
 input "mp-tool.mpiv" ;
 input "mp-mlib.mpiv" ;
@@ -47,6 +50,7 @@ let normalend = end ;
 
 if known mplib :
     def end = ; message "" ; message metafunversion ; message "" ; endinput  ; enddef ;
+    def bye = ; message "" ; message metafunversion ; message "" ; endinput  ; enddef ;
 else :
     def end = ; message "" ; message metafunversion ; message "" ; normalend ; enddef ;
 fi ;
diff --git a/Master/texmf-dist/metapost/context/base/mp-bare.mpiv b/Master/texmf-dist/metapost/context/base/mp-bare.mpiv
new file mode 100644
index 00000000000..c6194b1ee00
--- /dev/null
+++ b/Master/texmf-dist/metapost/context/base/mp-bare.mpiv
@@ -0,0 +1,93 @@
+%D \module
+%D   [       file=mp-bare.mpiv,
+%D        version=2014.10.31,
+%D          title=\CONTEXT\ \METAPOST\ graphics,
+%D       subtitle=plain plugins,
+%D         author=Hans Hagen,
+%D           date=\currentdate,
+%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
+%C
+%C This module is part of the \CONTEXT\ macro||package and is
+%C therefore copyrighted by \PRAGMA. See licen-en.pdf for
+%C details.
+
+if known context_bare : endinput ; fi ;
+boolean context_bare  ; context_bare := true ;
+
+numeric mfun_tt_w[], mfun_tt_h[], mfun_tt_d[] ;
+numeric mfun_tt_n ; mfun_tt_n := 0 ;
+picture mfun_tt_p ; mfun_tt_p := nullpicture ;
+picture mfun_tt_o ; mfun_tt_o := nullpicture ;
+picture mfun_tt_c ; mfun_tt_c := nullpicture ;
+
+if unknown mfun_trial_run :
+    boolean mfun_trial_run ;
+    mfun_trial_run := false ;
+fi ;
+
+if unknown mfun_first_run :
+    boolean mfun_first_run ;
+    mfun_first_run := true ;
+fi ;
+
+def mfun_reset_tex_texts =
+    mfun_tt_n := 0 ;
+    mfun_tt_p := nullpicture ;
+    mfun_tt_o := nullpicture ; % redundant
+    mfun_tt_c := nullpicture ; % redundant
+enddef ;
+
+def mfun_flush_tex_texts =
+    addto currentpicture also mfun_tt_p
+enddef ;
+
+extra_beginfig := extra_beginfig & "mfun_reset_tex_texts ;" ;
+extra_endfig   := "mfun_flush_tex_texts ; mfun_reset_tex_texts ; " & extra_endfig ;
+
+vardef colordecimals primary c =
+    if cmykcolor c  :
+        decimal cyanpart c & ":" & decimal magentapart c & ":" & decimal yellowpart c & ":" & decimal blackpart c
+    elseif rgbcolor c :
+        decimal redpart c & ":" & decimal greenpart c & ":" & decimal bluepart c
+    else :
+        decimal c
+    fi
+enddef ;
+
+vardef rawtextext(expr str) = % todo: avoid currentpicture
+    if str = "" :
+        nullpicture
+    else :
+        mfun_tt_n := mfun_tt_n + 1 ;
+        mfun_tt_c := nullpicture ;
+        if mfun_trial_run :
+            mfun_tt_o := nullpicture ;
+            addto mfun_tt_o doublepath origin _op_ ; % save drawoptions
+            addto mfun_tt_c doublepath unitsquare
+                withprescript "tx_number=" & decimal mfun_tt_n
+                withprescript "tx_stage=trial"
+                withprescript "tx_color=" & colordecimals colorpart mfun_tt_o
+                withpostscript str ;
+            addto mfun_tt_p also mfun_tt_c ;
+        elseif known mfun_tt_d[mfun_tt_n] :
+            addto mfun_tt_c doublepath unitsquare
+                xscaled mfun_tt_w[mfun_tt_n]
+                yscaled (mfun_tt_h[mfun_tt_n] + mfun_tt_d[mfun_tt_n])
+                shifted (0,-mfun_tt_d[mfun_tt_n])
+                withprescript "tx_number=" & decimal mfun_tt_n
+                withprescript "tx_stage=final" ;
+        else :
+            addto mfun_tt_c doublepath unitsquare ; % unitpicture
+        fi ;
+        mfun_tt_c
+    fi
+enddef ;
+
+primarydef str infont name = % nasty hack
+    if name = "" :
+        rawtextext(str)
+    else :
+        rawtextext("\definedfont[" & name & "]" & str)
+    fi
+enddef ;
+
diff --git a/Master/texmf-dist/metapost/context/base/mp-base.mpiv b/Master/texmf-dist/metapost/context/base/mp-base.mpiv
index 94379050bc8..28eb57fb895 100644
--- a/Master/texmf-dist/metapost/context/base/mp-base.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-base.mpiv
@@ -195,7 +195,8 @@ yellow     := (1,1,0) ;
 background := white ; % obsolete
 
 let graypart  = greypart  ;
-let graycolor = greycolor ;
+let greycolor = numeric ;
+let graycolor = numeric ;
 
 % color part (will be overloaded)
 
@@ -865,7 +866,7 @@ vardef labels@#(text t) =
     endfor
 enddef ;
 
-% til lhere
+% till lhere
 
 vardef dotlabels@#(text t) =
     forsuffixes $=t:
@@ -881,17 +882,19 @@ vardef penlabels@#(text t) =
     endfor
 enddef ;
 
+% range 4 thru 10
+
 def range expr x =
-    numtok[x]
+    _numtok_[x]
 enddef ;
 
-def numtok suffix x =
+def _numtok_ suffix x =
     x
 enddef ;
 
 tertiarydef m thru n =
     m for x=m+1 step 1 until n :
-        , numtok[x]
+        , _numtok_[x]
     endfor
 enddef ;
 
diff --git a/Master/texmf-dist/metapost/context/base/mp-chem.mpiv b/Master/texmf-dist/metapost/context/base/mp-chem.mpiv
index a316a1a30cb..b861d3f123e 100644
--- a/Master/texmf-dist/metapost/context/base/mp-chem.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-chem.mpiv
@@ -11,7 +11,8 @@
 %C therefore copyrighted by \PRAGMA. See licen-en.pdf for
 %C details.
 
-%D This module is incomplete and experimental.
+%D This module is incomplete and experimental. Okay, it's not that bad but we do need
+%D some disclaimer.
 
 % either consistent setting or not
 
@@ -131,6 +132,8 @@ vardef chem_init_some (suffix $) (expr e) =
             fi
             if not chem_star[$] :
                 scaled (.5/(sind .5chem_num1))
+                % carbon-carbon benzene bond length
+                scaled (1.4/1.54)
             fi ;
     fi ;
 
@@ -300,7 +303,6 @@ enddef ;
 
 chem_init_all ; % WHY does this not work unless defined and then called?
 
-
 % Like most often in ConTeXt, we will trap but then silently ignore mistaken use,
 % unless of course the error be too harmful...
 
@@ -529,6 +531,17 @@ vardef chem_set (suffix $) =
     % This is a fairly complicated optimization and ajustement. It took some
     % thinking to get right, so beware!
 
+    % And then even more time fixing a bug of a rotation +- half the symmetry
+    % angle of a structure depending on the scale and/or the font size
+    % (through chem_b_length).
+
+    % first save the symmetry angle of the structure (as in chem_rot):
+    chem_num0 := if chem_stacked[$] : 3 else : 0 fi ;
+    chem_num9 := if chem_tetra[$] : 360 else :
+                 abs(angle(point 0+chem_num0 of chem_b_path[$]) -
+                     angle(point 1+chem_num0 of chem_b_path[$]))
+                 fi ;
+
     if (chem_adjacent<>0) and chem_star[P] and chem_star[$] :
         % nop
         chem_adjacent := 0 ;
@@ -581,7 +594,8 @@ vardef chem_set (suffix $) =
                           -((point (chem_adjacent-1) of chem_b_path[P]) chem_transformed(P)) ;
         fi
         % adjust the bond angles
-        chem_rotation := (chem_rotation + angle(chem_pair1)-angle(chem_pair3)) mod 360 ;
+        chem_num4 := (angle(chem_pair1)-angle(chem_pair3)) zmod chem_num9 ;
+        chem_rotation := chem_rotation + chem_num4 ;
         if not chem_star[$] :
             chem_pair4 :=
                 if chem_star[P] :
@@ -666,7 +680,8 @@ vardef chem_set (suffix $) =
                 fi
             endfor
             if not chem_front[$] : % adjust rotation
-                chem_rotation := (chem_rotation + angle(chem_pair1)-angle(chem_pair3)) mod 360 ;
+                chem_num4 := angle(chem_pair1)-angle(chem_pair3) ;
+                chem_rotation := (chem_rotation + chem_num4) mod 360 ;
             fi ;
             chem_t := identity chem_transformed($) ;
             chem_pair4 := (point chem_num3 of chem_b_path[$]) transformed chem_t ;
@@ -674,6 +689,9 @@ vardef chem_set (suffix $) =
                 currentpicture := currentpicture shifted chem_pair4 ;
                 chem_origin    := chem_origin    shifted chem_pair4 ;
             fi
+            if not chem_front[$] : % adjust rotation
+                chem_rotation := chem_rotation zmod chem_num9 ;
+            fi
         fi
         chem_substituent := 0 ;
     fi ;
@@ -1571,9 +1589,9 @@ vardef chem_rot (suffix $) (expr d, s) = % ROT
             chem_rotation := 0
         else :
             chem_num0 := if chem_stacked[$] : 3 else : 0 fi ;
-            chem_num1 := .5(angle(point d+chem_num0 of chem_b_path[$]) -
+            chem_num1 := .5(angle(point d+chem_num0   of chem_b_path[$]) -
                             angle(point d+chem_num0-1 of chem_b_path[$])) ;
-            chem_rotation := (chem_rotation + s*chem_num1) mod 360 ;
+            chem_rotation := (chem_rotation + s*chem_num1) zmod 360 ;
         fi
     fi
 enddef ;
@@ -1584,7 +1602,7 @@ vardef chem_mir (suffix $) (expr d, s)  = % MIR
     if not chem_front[$] :
         if d=0 : % inversion
             if chem_mirror=origin :
-                chem_rotation := (chem_rotation + 180*s) mod 360 ;
+                chem_rotation := (chem_rotation + 180*s) zmod 360 ;
             else :
                 chem_mirror := chem_mirror rotated 90 ;
             fi
@@ -1600,7 +1618,7 @@ vardef chem_mir (suffix $) (expr d, s)  = % MIR
                     chem_num0 := -360 - chem_num0 ;
                 fi
                 chem_num0 := chem_num0 * s ;
-                chem_rotation := (chem_rotation + 2chem_num0) mod 360 ;
+                chem_rotation := (chem_rotation + 2chem_num0) zmod 360 ;
                 chem_mirror := origin ;
             fi
         fi
diff --git a/Master/texmf-dist/metapost/context/base/mp-func.mpiv b/Master/texmf-dist/metapost/context/base/mp-func.mpiv
index 58df711f2f3..b1b9d6d5d22 100644
--- a/Master/texmf-dist/metapost/context/base/mp-func.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-func.mpiv
@@ -23,30 +23,36 @@ mfun_pathconnectors[0] := ","   ;
 mfun_pathconnectors[1] := "--"  ;
 mfun_pathconnectors[2] := ".."  ;
 mfun_pathconnectors[3] := "..." ;
+mfun_pathconnectors[4] := "---" ;
 
 def pathconnectors = mfun_pathconnectors enddef ;
 
 vardef mfun_function (expr f) (expr u, t, b, e, s) =
     save x ; numeric x ;
+    save c ; string c ; c := if string f : f else : mfun_pathconnectors[f] fi ;
     for xx := b step s until e :
         hide (x := xx ;)
         if xx > b :
-            scantokens(mfun_pathconnectors[f])
+          scantokens(c)
         fi
         (scantokens(u),scantokens(t))
     endfor
 enddef ;
 
-def function       = mfun_function     enddef ; % let doesn't work here
-def punkedfunction = mfun_function (1) enddef ;
-def curvedfunction = mfun_function (2) enddef ;
-def tightfunction  = mfun_function (3) enddef ;
+def function            = mfun_function     enddef ; % let doesn't work here
+def constructedfunction = mfun_function     enddef ;
+def straightfunction    = mfun_function (1) enddef ;
+def curvedfunction      = mfun_function (2) enddef ;
+
+% def punkedfunction   = mfun_function (1) enddef ; % same as straightfunction
+% def tightfunction    = mfun_function (3) enddef ; % same as curvedfunction
 
 vardef mfun_constructedpath (expr f) (text t) =
     save ok ; boolean ok ; ok := false ;
+    save c ; string c ; c := if string f : f else : mfun_pathconnectors[f] fi ;
     for i=t :
         if ok :
-            scantokens(mfun_pathconnectors[f])
+            scantokens(c)
         else :
             ok := true ;
         fi
@@ -55,24 +61,27 @@ vardef mfun_constructedpath (expr f) (text t) =
 enddef ;
 
 def constructedpath = mfun_constructedpath     enddef ; % let doesn't work here
-def punkedpath      = mfun_constructedpath (1) enddef ;
+def straightpath    = mfun_constructedpath (1) enddef ;
 def curvedpath      = mfun_constructedpath (2) enddef ;
-def tightpath       = mfun_constructedpath (3) enddef ;
+
+% def punkedpath      = mfun_constructedpath (1) enddef ; % same as straightpath
+% def tightpath       = mfun_constructedpath (3) enddef ; % same as curvedpath
 
 vardef mfun_constructedpairs (expr f) (text p) =
     save i ; i := -1 ;
+    save c ; string c ; c := if string f : f else : mfun_pathconnectors[f] fi ;
     forever :
         exitif unknown p[incr(i)] ;
         if i>0 :
-            scantokens(mfun_pathconnectors[f])
+            scantokens(c)
         fi
         p[i]
     endfor
 enddef ;
 
 def constructedpairs = mfun_constructedpairs     enddef ; % let doesn't work here
-def punkedpairs      = mfun_constructedpairs (1) enddef ;
+def straightpairs    = mfun_constructedpairs (1) enddef ;
 def curvedpairs      = mfun_constructedpairs (2) enddef ;
-def tightpairs       = mfun_constructedpairs (3) enddef ;
-
 
+% def punkedpairs      = mfun_constructedpairs (1) enddef ; % same as straightpairs
+% def tightpairs       = mfun_constructedpairs (3) enddef ; % same as curvedpairs
diff --git a/Master/texmf-dist/metapost/context/base/mp-grap.mpiv b/Master/texmf-dist/metapost/context/base/mp-grap.mpiv
index 6d2924c5263..4fd8ee5bd59 100644
--- a/Master/texmf-dist/metapost/context/base/mp-grap.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-grap.mpiv
@@ -17,7 +17,10 @@ boolean context_grap ; context_grap := true ;
 
 % Below is a modified graph.mp
 
-if epsilon/4 = 0 : % numbersystem="scaled" : (not reliable...)
+show numbersystem, numberprecision ;
+
+%if epsilon/4 = 0 :
+if numbersystem <> "double" :
     errmessage "The graph macros require the double precision number system." ;
     endinput ;
 fi
@@ -75,7 +78,7 @@ newinternal mlogten ;         mlogten         := mlog(10) ;
 newinternal largestmantissa ; largestmantissa := 2**52 ; % internal double warningcheck
 newinternal singleinfinity ;  singleinfinity  := 2**128 ;
 newinternal doubleinfinity ;  doubleinfinity  := 2**1024 ;
-Mzero := -largestmantissa ; % Note that we get arithmetic overflows if we set to -doubleinfinity
+%Mzero := -largestmantissa ; % Note that we get arithmetic overflows if we set to -doubleinfinity
 
 % Safely convert a number to mlog form, trapping zero.
 
@@ -428,13 +431,15 @@ vardef graph_pair_adjust(expr p)(suffix tx, ty) = (tx xpart p, ty ypart p) endde
 
 vardef graph_convert_user_path_to_internal primary p =
   interim warningcheck :=0 ;
-  graph_scan_path(p,
-    (abs X_.graph_coordinate_type<>linear) or (abs Y_.graph_coordinate_type<>linear),
-    if abs X_.graph_coordinate_type=log : graph_mlog fi,
-    if abs Y_.graph_coordinate_type=log : graph_mlog fi)
-    transformed  (identity
-      if X_.graph_coordinate_type<0 : xscaled -1 fi
-      if Y_.graph_coordinate_type<0 : yscaled -1 fi)
+  if known p :
+    graph_scan_path(p,
+      (abs X_.graph_coordinate_type<>linear) or (abs Y_.graph_coordinate_type<>linear),
+      if abs X_.graph_coordinate_type=log : graph_mlog fi,
+      if abs Y_.graph_coordinate_type=log : graph_mlog fi)
+      transformed  (identity
+        if X_.graph_coordinate_type<0 : xscaled -1 fi
+        if Y_.graph_coordinate_type<0 : yscaled -1 fi)
+  fi
 enddef ;
 
 % Convert label location t_ from user graph coords to internal graph coords.
@@ -520,10 +525,11 @@ enddef ;
 
 % Execute c for each line of data read from file f, and stop at the first
 % line with no data.  Commands c can use line number i and tokens $1, $2, ...
+% and j is the number of fields.
 
 def gdata(expr f)(suffix $)(text c) =
-  boolean flag ;
-  for i=1 upto infinity :
+  %boolean flag ; % not used?
+  for i=1 upto largestmantissa :
     exitunless graph_read_line$(f) ;
     c
   endfor
diff --git a/Master/texmf-dist/metapost/context/base/mp-luas.mpiv b/Master/texmf-dist/metapost/context/base/mp-luas.mpiv
index b926b586c46..c919ba2159c 100644
--- a/Master/texmf-dist/metapost/context/base/mp-luas.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-luas.mpiv
@@ -13,6 +13,15 @@
 
 if known context_luas : endinput ; fi ;
 
+% When I prototyped the runscript primitive I was just thinking of a usage like
+% the original \directlua primitive in luatex: genererate something and pipe
+% that back to metapost, and have access to some internals. Instead of compiling
+% the code a the metapost end here we delegate that to the lua end. Only strings
+% get passed. Of course in the end the real usage got a bit beyong the intended
+% usage. So, in addition to some definitions here there are and will be use in
+% other metafun modules too. Of course in retrospect I should have done this five
+% years earlier.
+
 boolean context_luas ; context_luas := true ;
 
 % First variant:
diff --git a/Master/texmf-dist/metapost/context/base/mp-mlib.mpiv b/Master/texmf-dist/metapost/context/base/mp-mlib.mpiv
index 56815028e8f..b19f47f1e55 100644
--- a/Master/texmf-dist/metapost/context/base/mp-mlib.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-mlib.mpiv
@@ -60,32 +60,70 @@ def namedcolor (expr n) =
     withprescript "sp_name=" & n
 enddef ;
 
+% def spotcolor(expr n, v) =
+%     1
+%     withprescript "sp_type=spot"
+%     withprescript "sp_name="  & n
+%     withprescript "sp_value=" & (if numeric v : decimal v else : v fi)
+% enddef ;
+%
+% def multitonecolor(expr name, fractions, components, value) =
+%     1
+%     withprescript "sp_type=multitone"
+%     withprescript "sp_name="       & name
+%     withprescript "sp_fractions="  & decimal fractions
+%     withprescript "sp_components=" & components
+%     withprescript "sp_value="      & value
+% enddef ;
+
 def spotcolor(expr n, v) =
     1
     withprescript "sp_type=spot"
     withprescript "sp_name="  & n
-    withprescript "sp_value=" & v
+    withprescript "sp_value=" & colordecimals v
 enddef ;
 
-def multitonecolor(expr name, fractions, components, value) =
+def multitonecolor(expr name)(text t) =
     1
     withprescript "sp_type=multitone"
-    withprescript "sp_name="       & name
-    withprescript "sp_fractions="  & decimal fractions
-    withprescript "sp_components=" & components
-    withprescript "sp_value="      & value
+    withprescript "sp_name=" & name
+    withprescript "sp_value=" & colordecimalslist(t)
 enddef ;
 
-def transparent(expr alternative, transparency)(text c) =
+def transparent(expr a, t)(text c) = % use withtransparency instead
     1 % this permits withcolor x intoshade y
-    withprescript "tr_alternative="  & decimal transparency_alternative_to_number(alternative)
-    withprescript "tr_transparency=" & decimal transparency
+    withprescript "tr_alternative="  & decimal transparency_alternative_to_number(a)
+    withprescript "tr_transparency=" & decimal t
     withcolor c
 enddef ;
 
-def withtransparency(expr alternative, transparency) =
-    withprescript "tr_alternative="  & decimal transparency_alternative_to_number(alternative)
-    withprescript "tr_transparency=" & decimal transparency
+% def withtransparency(expr a, t) =
+%     withprescript "tr_alternative="  & decimal transparency_alternative_to_number(a)
+%     withprescript "tr_transparency=" & decimal t
+% enddef ;
+
+let transparency = pair ;
+
+% def withtransparency expr t =
+%     withprescript "tr_alternative="  & decimal transparency_alternative_to_number(xpart t)
+%     withprescript "tr_transparency=" & decimal ypart t
+% enddef ;
+%
+% withtransparency (1,.5)
+% withtransparency ("normal",.5)
+
+def withtransparency (expr t) (text rest) =
+    if pair t :
+        withprescript "tr_alternative="  & decimal transparency_alternative_to_number(xpart t)
+        withprescript "tr_transparency=" & decimal ypart t
+    else :
+        mfun_with_transparency (transparency_alternative_to_number(t))
+    fi rest
+enddef ;
+
+def mfun_with_transparency (expr a) expr t =
+    withprescript "tr_alternative="  & decimal a
+    withprescript "tr_transparency=" & decimal t
 enddef ;
 
 def cmyk(expr c, m, y, k) = % provided for downward compability
@@ -96,7 +134,8 @@ enddef ;
 
 newinternal textextoffset ; textextoffset := 0 ;
 
-numeric mfun_tt_w[], mfun_tt_h[], mfun_tt_d[] ; % we can consider using colors (less hash space)
+%%%%%%% mfun_tt_w[], mfun_tt_h[], mfun_tt_d[] ; % we can consider using colors (less hash space)
+color   mfun_tt_b ;
 numeric mfun_tt_n ; mfun_tt_n := 0 ;
 picture mfun_tt_p ; mfun_tt_p := nullpicture ;
 picture mfun_tt_o ; mfun_tt_o := nullpicture ;
@@ -135,44 +174,10 @@ extra_beginfig := extra_beginfig & "mfun_reset_tex_texts ;" ;
 % flush twice: once in location in order to pick up e.g. color properties,
 % and once at the end because we need to flush missing ones.
 
-% vardef rawtextext(expr str) =
-%     if str = "" :
-%         nullpicture
-%     elseif mfun_trial_run :
-%         mfun_tt_n := mfun_tt_n + 1 ;
-%         mfun_tt_o := image(draw origin) ; % save drawoptions
-%         addto mfun_tt_p doublepath unitsquare
-%             withprescript "tx_number=" & decimal mfun_tt_n
-%             withprescript "tx_stage=extra"
-%             withpostscript str ;
-%         image (
-%             addto currentpicture doublepath unitsquare
-%                 withprescript "tx_number=" & decimal mfun_tt_n
-%                 withprescript "tx_stage=trial"
-%                 withprescript "tx_color=" & colordecimals colorpart mfun_tt_o
-%                 withpostscript str
-%         ; )
-%     else :
-%         mfun_tt_n := mfun_tt_n + 1 ;
-%         if known mfun_tt_d[mfun_tt_n] :
-%             image (
-%                 addto currentpicture doublepath unitsquare
-%                     xscaled mfun_tt_w[mfun_tt_n]
-%                     yscaled (mfun_tt_h[mfun_tt_n] + mfun_tt_d[mfun_tt_n])
-%                     withprescript "tx_number=" & decimal mfun_tt_n
-%                     withprescript "tx_stage=final"
-%                   % withpostscript str ; % for tracing
-%             ; ) shifted (0,-mfun_tt_d[mfun_tt_n])
-%         else :
-%             image (
-%                 addto currentpicture doublepath unitsquare
-%             ; )
-%         fi
-%     fi
-% enddef ;
+% see mp-keep.mpiv for older code
 
-% vardef rawtextext(expr str) = % todo: avoid currentpicture
-%     if str = "" :
+% vardef rawtextext(expr s) = % todo: avoid currentpicture
+%     if s = "" :
 %         nullpicture
 %     else :
 %         mfun_tt_n := mfun_tt_n + 1 ;
@@ -180,15 +185,12 @@ extra_beginfig := extra_beginfig & "mfun_reset_tex_texts ;" ;
 %         if mfun_trial_run :
 %             mfun_tt_o := nullpicture ;
 %             addto mfun_tt_o doublepath origin _op_ ; % save drawoptions
-%             addto mfun_tt_p doublepath unitsquare
-%                 withprescript "tx_number=" & decimal mfun_tt_n
-%                 withprescript "tx_stage=extra"
-%                 withpostscript str ;
 %             addto mfun_tt_c doublepath unitsquare
 %                 withprescript "tx_number=" & decimal mfun_tt_n
 %                 withprescript "tx_stage=trial"
 %                 withprescript "tx_color=" & colordecimals colorpart mfun_tt_o
-%                 withpostscript str ;
+%                 withpostscript s ;
+%             addto mfun_tt_p also mfun_tt_c ;
 %         elseif known mfun_tt_d[mfun_tt_n] :
 %             addto mfun_tt_c doublepath unitsquare
 %                 xscaled mfun_tt_w[mfun_tt_n]
@@ -203,8 +205,8 @@ extra_beginfig := extra_beginfig & "mfun_reset_tex_texts ;" ;
 %     fi
 % enddef ;
 
-vardef rawtextext(expr str) = % todo: avoid currentpicture
-    if str = "" :
+vardef rawtextext(expr s) = % todo: avoid currentpicture
+    if s = "" :
         nullpicture
     else :
         mfun_tt_n := mfun_tt_n + 1 ;
@@ -216,17 +218,16 @@ vardef rawtextext(expr str) = % todo: avoid currentpicture
                 withprescript "tx_number=" & decimal mfun_tt_n
                 withprescript "tx_stage=trial"
                 withprescript "tx_color=" & colordecimals colorpart mfun_tt_o
-                withpostscript str ;
+                withpostscript s ;
             addto mfun_tt_p also mfun_tt_c ;
-        elseif known mfun_tt_d[mfun_tt_n] :
+        else :
+            mfun_tt_b := lua.mp.tt_dimensions(mfun_tt_n) ;
             addto mfun_tt_c doublepath unitsquare
-                xscaled mfun_tt_w[mfun_tt_n]
-                yscaled (mfun_tt_h[mfun_tt_n] + mfun_tt_d[mfun_tt_n])
-                shifted (0,-mfun_tt_d[mfun_tt_n])
+                xscaled redpart mfun_tt_b
+                yscaled (greenpart mfun_tt_b + bluepart mfun_tt_b)
+                shifted (0,- bluepart mfun_tt_b)
                 withprescript "tx_number=" & decimal mfun_tt_n
                 withprescript "tx_stage=final" ;
-        else :
-            addto mfun_tt_c doublepath unitsquare ; % unitpicture
         fi ;
         mfun_tt_c
     fi
@@ -234,7 +235,10 @@ enddef ;
 
 % More text
 
-defaultfont := "Mono" ; % was cmr10, could be lmmono10-regular, but is fed into context anyway
+defaultfont  := "Mono" ;
+defaultscale := 1 ;
+
+extra_beginfig := extra_beginfig & "defaultscale:=1;" ;
 
 vardef fontsize expr name =
     save size ; numeric size ;
@@ -403,19 +407,171 @@ enddef ;
 
 let normalinfont = infont ;
 
-primarydef str infont name = % nasty hack
+primarydef s infont name = % nasty hack
     if name = "" :
-        textext(str)
+        textext(s)
     else :
-        textext("\definedfont[" & name & "]" & str)
+        textext("\definedfont[" & name & "]" & s)
     fi
 enddef ;
 
+% Helper
+
+string mfun_prescript_separator ; mfun_prescript_separator := char(13) ;
+
 % Shades
 
-newinternal shadefactor  ; shadefactor  := 1 ;
-pair        shadeoffset  ; shadeoffset  := origin ;
-boolean     trace_shades ; trace_shades := false ;
+% for while we had this:
+
+newinternal shadefactor  ; shadefactor  := 1 ;      % currently obsolete
+pair        shadeoffset  ; shadeoffset  := origin ; % currently obsolete
+boolean     trace_shades ; trace_shades := false ;  % still there
+
+% def withlinearshading (expr a, b) =
+%     withprescript "sh_type=linear"
+%     withprescript "sh_domain=0 1"
+%     withprescript "sh_factor="   & decimal shadefactor
+%     withprescript "sh_center_a=" & ddecimal (a shifted shadeoffset)
+%     withprescript "sh_center_b=" & ddecimal (b shifted shadeoffset)
+% enddef ;
+%
+% def withcircularshading (expr a, b, ra, rb) =
+%     withprescript "sh_type=circular"
+%     withprescript "sh_domain=0 1"
+%     withprescript "sh_factor="   & decimal shadefactor
+%     withprescript "sh_center_a=" & ddecimal (a shifted shadeoffset)
+%     withprescript "sh_center_b=" & ddecimal (b shifted shadeoffset)
+%     withprescript "sh_radius_a=" & decimal ra
+%     withprescript "sh_radius_b=" & decimal rb
+% enddef ;
+%
+% def withshading (expr how)(text rest) =
+%     if how = "linear" :
+%         withlinearshading(rest)
+%     elseif how = "circular" :
+%         withcircularshading(rest)
+%     else :
+%         % nothing
+%     fi
+% enddef ;
+%
+% def withfromshadecolor expr t =
+%     withprescript "sh_color=into"
+%     withprescript "sh_color_a=" & colordecimals t
+% enddef ;
+
+% def withtoshadecolor expr t =
+%     withprescript "sh_color=into"
+%     withprescript "sh_color_b=" & colordecimals t
+% enddef ;
+
+% but this is nicer
+
+path mfun_shade_path ;
+
+primarydef p withshademethod m =
+    hide(mfun_shade_path := p ;)
+    p
+    withprescript "sh_domain=0 1"
+    withprescript "sh_color=into"
+    withprescript "sh_color_a=" & colordecimals white
+    withprescript "sh_color_b=" & colordecimals black
+    if m = "linear" :
+        withprescript "sh_type=linear"
+        withprescript "sh_factor=1"
+        withprescript "sh_center_a=" & ddecimal llcorner p
+        withprescript "sh_center_b=" & ddecimal urcorner p
+    else :
+        withprescript "sh_type=circular"
+        withprescript "sh_factor=1.2"
+        withprescript "sh_center_a=" & ddecimal center p
+        withprescript "sh_center_b=" & ddecimal center p
+        withprescript "sh_radius_a=" & decimal 0
+        withprescript "sh_radius_b=" & decimal ( max (
+            (xpart center p - xpart llcorner p) ++ (ypart center p - ypart llcorner p),
+            (xpart center p - xpart ulcorner p) ++ (ypart ulcorner p - ypart center p),
+            (xpart lrcorner p - xpart center p) ++ (ypart center p - ypart lrcorner p),
+            (xpart urcorner p - xpart center p) ++ (ypart urcorner p - ypart center p)
+        ) )
+    fi
+enddef ;
+
+def withshadevector expr a =
+    withprescript "sh_center_a=" & ddecimal (point xpart a of mfun_shade_path)
+    withprescript "sh_center_b=" & ddecimal (point ypart a of mfun_shade_path)
+enddef ;
+
+def withshadecenter expr a =
+    withprescript "sh_center_a=" & ddecimal (
+        center mfun_shade_path shifted (
+            xpart a * bbwidth (mfun_shade_path)/2,
+            ypart a * bbheight(mfun_shade_path)/2
+        )
+    )
+enddef ;
+
+def withshadedomain expr d =
+    withprescript "sh_domain=" & ddecimal d
+enddef ;
+
+def withshadefactor expr f =
+    withprescript "sh_factor=" & decimal f
+enddef ;
+
+def withshadecolors (expr a, b) =
+    withprescript "sh_color=into"
+    withprescript "sh_color_a=" & colordecimals a
+    withprescript "sh_color_b=" & colordecimals b
+enddef ;
+
+primarydef a shadedinto b = % withcolor red shadedinto green
+    1 % does not work with transparency
+    withprescript "sh_color=into"
+    withprescript "sh_color_a=" & colordecimals a
+    withprescript "sh_color_b=" & colordecimals b
+enddef ;
+
+primarydef p withshade sc =
+    p withprescript mfun_defined_cs_pre[sc]
+enddef ;
+
+def defineshade suffix s =
+    mfun_defineshade(str s)
+enddef ;
+
+def mfun_defineshade (expr s) text t =
+    expandafter def scantokens s = t enddef ;
+enddef ;
+
+def shaded text s =
+    s
+enddef ;
+
+% Old macros:
+
+def withcircularshade (expr a, b, ra, rb, ca, cb) =
+    withprescript "sh_type=circular"
+    withprescript "sh_domain=0 1"
+    withprescript "sh_factor=1"
+    withprescript "sh_color_a="  & colordecimals ca
+    withprescript "sh_color_b="  & colordecimals cb
+    withprescript "sh_center_a=" & ddecimal a % (a shifted shadeoffset)
+    withprescript "sh_center_b=" & ddecimal b % (b shifted shadeoffset)
+    withprescript "sh_radius_a=" & decimal ra
+    withprescript "sh_radius_b=" & decimal rb
+enddef ;
+
+def withlinearshade (expr a, b, ca, cb) =
+    withprescript "sh_type=linear"
+    withprescript "sh_domain=0 1"
+    withprescript "sh_factor=1"
+    withprescript "sh_color_a="  & colordecimals ca
+    withprescript "sh_color_b="  & colordecimals cb
+    withprescript "sh_center_a=" & ddecimal a % (a shifted shadeoffset)
+    withprescript "sh_center_b=" & ddecimal b % (b shifted shadeoffset)
+enddef ;
+
+% replaced (obsolete):
 
 def set_linear_vector (suffix a,b)(expr p,n) =
     if     (n=1) : a := llcorner p ; b := urcorner p ;
@@ -430,7 +586,7 @@ def set_linear_vector (suffix a,b)(expr p,n) =
     fi ;
 enddef ;
 
-def set_circular_vector (suffix ab, r)(expr p,n) =
+def set_circular_vector (suffix ab,r)(expr p,n) =
     if     (n=1) : ab := llcorner p ;
     elseif (n=2) : ab := lrcorner p ;
     elseif (n=3) : ab := urcorner p ;
@@ -453,7 +609,7 @@ enddef ;
 
 def linear_shade (expr p, n, ca, cb) =
     begingroup ;
-        save a, b, sh ; pair a, b ;
+        save a, b ; pair a, b ;
         set_linear_vector(a,b)(p,n) ;
         fill p withlinearshade(a,b,ca,cb) ;
         if trace_shades :
@@ -462,43 +618,19 @@ def linear_shade (expr p, n, ca, cb) =
     endgroup ;
 enddef ;
 
-def withcircularshade (expr a, b, ra, rb, ca, cb) =
-    withprescript "sh_type=circular"
-    withprescript "sh_domain=0 1"
-    withprescript "sh_factor="   & decimal shadefactor
-    withprescript "sh_color_a="  & colordecimals ca
-    withprescript "sh_color_b="  & colordecimals cb
-    withprescript "sh_center_a=" & ddecimal (a shifted shadeoffset)
-    withprescript "sh_center_b=" & ddecimal (b shifted shadeoffset)
-    withprescript "sh_radius_a=" & decimal ra
-    withprescript "sh_radius_b=" & decimal rb
-enddef ;
-
-def withlinearshade (expr a, b, ca, cb) =
-    withprescript "sh_type=linear"
-    withprescript "sh_domain=0 1"
-    withprescript "sh_factor="   & decimal shadefactor
-    withprescript "sh_color_a="  & colordecimals ca
-    withprescript "sh_color_b="  & colordecimals cb
-    withprescript "sh_center_a=" & ddecimal (a shifted shadeoffset)
-    withprescript "sh_center_b=" & ddecimal (b shifted shadeoffset)
-enddef ;
-
 string mfun_defined_cs_pre[] ; numeric mfun_defined_cs ; mfun_defined_cs := 0 ;
 
-string mfun_prescript_separator ; mfun_prescript_separator := char(13) ;
-
 vardef define_circular_shade (expr a, b, ra, rb, ca, cb) =
     mfun_defined_cs := mfun_defined_cs + 1 ;
     mfun_defined_cs_pre[mfun_defined_cs] := "sh_type=circular"
-      & mfun_prescript_separator & "sh_domain=0 1"
-      & mfun_prescript_separator & "sh_factor="   & decimal shadefactor
-      & mfun_prescript_separator & "sh_color_a="  & colordecimals ca
-      & mfun_prescript_separator & "sh_color_b="  & colordecimals cb
-      & mfun_prescript_separator & "sh_center_a=" & ddecimal (a shifted shadeoffset)
-      & mfun_prescript_separator & "sh_center_b=" & ddecimal (b shifted shadeoffset)
-      & mfun_prescript_separator & "sh_radius_a=" & decimal ra
-      & mfun_prescript_separator & "sh_radius_b=" & decimal rb
+    & mfun_prescript_separator & "sh_domain=0 1"
+    & mfun_prescript_separator & "sh_factor=1"
+    & mfun_prescript_separator & "sh_color_a="  & colordecimals ca
+    & mfun_prescript_separator & "sh_color_b="  & colordecimals cb
+    & mfun_prescript_separator & "sh_center_a=" & ddecimal a % (a shifted shadeoffset)
+    & mfun_prescript_separator & "sh_center_b=" & ddecimal b % (b shifted shadeoffset)
+    & mfun_prescript_separator & "sh_radius_a=" & decimal ra
+    & mfun_prescript_separator & "sh_radius_b=" & decimal rb
     ;
     mfun_defined_cs
 enddef ;
@@ -506,52 +638,49 @@ enddef ;
 vardef define_linear_shade (expr a, b, ca, cb) =
     mfun_defined_cs := mfun_defined_cs + 1 ;
     mfun_defined_cs_pre[mfun_defined_cs] := "sh_type=linear"
-      & mfun_prescript_separator & "sh_domain=0 1"
-      & mfun_prescript_separator & "sh_factor=" & decimal shadefactor
-      & mfun_prescript_separator & "sh_color_a=" & colordecimals ca
-      & mfun_prescript_separator & "sh_color_b=" & colordecimals cb
-      & mfun_prescript_separator & "sh_center_a=" & ddecimal (a shifted shadeoffset)
-      & mfun_prescript_separator & "sh_center_b=" & ddecimal (b shifted shadeoffset)
+    & mfun_prescript_separator & "sh_domain=0 1"
+    & mfun_prescript_separator & "sh_factor=1"
+    & mfun_prescript_separator & "sh_color_a=" & colordecimals ca
+    & mfun_prescript_separator & "sh_color_b=" & colordecimals cb
+    & mfun_prescript_separator & "sh_center_a=" & ddecimal a % (a shifted shadeoffset)
+    & mfun_prescript_separator & "sh_center_b=" & ddecimal b % (b shifted shadeoffset)
     ;
     mfun_defined_cs
 enddef ;
 
-primarydef p withshade sc =
-    p withprescript mfun_defined_cs_pre[sc]
-enddef ;
-
-
-vardef define_sampled_linear_shade(expr a,b,n)(text t) =
-    mfun_defined_cs := mfun_defined_cs + 1 ;
-    mfun_defined_cs_pre[mfun_defined_cs] := "ssh_type=linear"
-      & mfun_prescript_separator & "ssh_center_a=" & ddecimal (a shifted shadeoffset)
-      & mfun_prescript_separator & "ssh_center_b=" & ddecimal (b shifted shadeoffset)
-      & mfun_prescript_separator & "ssh_nofcolors=" & decimal n
-      & mfun_prescript_separator & "ssh_domain=" & domstr
-      & mfun_prescript_separator & "ssh_extend=" & extstr
-      & mfun_prescript_separator & "ssh_colors=" & colstr
-      & mfun_prescript_separator & "ssh_bounds=" & bndstr
-      & mfun_prescript_separator & "ssh_ranges=" & ranstr
-    ;
-    mfun_defined_cs
-enddef ;
-
-vardef define_sampled_circular_shade(expr a,b,ra,rb,n)(text t) =
-    mfun_defined_cs := mfun_defined_cs + 1 ;
-    mfun_defined_cs_pre[mfun_defined_cs] := "ssh_type=circular"
-      & mfun_prescript_separator & "ssh_center_a=" & ddecimal (a shifted shadeoffset)
-      & mfun_prescript_separator & "ssh_radius_a=" & decimal ra
-      & mfun_prescript_separator & "ssh_center_b=" & ddecimal (b shifted shadeoffset)
-      & mfun_prescript_separator & "ssh_radius_b=" & decimal rb
-      & mfun_prescript_separator & "ssh_nofcolors=" & decimal n
-      & mfun_prescript_separator & "ssh_domain=" & domstr
-      & mfun_prescript_separator & "ssh_extend=" & extstr
-      & mfun_prescript_separator & "ssh_colors=" & colstr
-      & mfun_prescript_separator & "ssh_bounds=" & bndstr
-      & mfun_prescript_separator & "ssh_ranges=" & ranstr
-    ;
-    mfun_defined_cs
-enddef ;
+% I lost the example code that uses this:
+%
+% vardef define_sampled_linear_shade(expr a,b,n)(text t) =
+%     mfun_defined_cs := mfun_defined_cs + 1 ;
+%     mfun_defined_cs_pre[mfun_defined_cs] := "ssh_type=linear"
+%     & mfun_prescript_separator & "ssh_center_a=" & ddecimal (a shifted shadeoffset)
+%     & mfun_prescript_separator & "ssh_center_b=" & ddecimal (b shifted shadeoffset)
+%     & mfun_prescript_separator & "ssh_nofcolors=" & decimal n
+%     & mfun_prescript_separator & "ssh_domain=" & domstr
+%     & mfun_prescript_separator & "ssh_extend=" & extstr
+%     & mfun_prescript_separator & "ssh_colors=" & colstr
+%     & mfun_prescript_separator & "ssh_bounds=" & bndstr
+%     & mfun_prescript_separator & "ssh_ranges=" & ranstr
+%     ;
+%     mfun_defined_cs
+% enddef ;
+%
+% vardef define_sampled_circular_shade(expr a,b,ra,rb,n)(text t) =
+%     mfun_defined_cs := mfun_defined_cs + 1 ;
+%     mfun_defined_cs_pre[mfun_defined_cs] := "ssh_type=circular"
+%     & mfun_prescript_separator & "ssh_center_a=" & ddecimal (a shifted shadeoffset)
+%     & mfun_prescript_separator & "ssh_radius_a=" & decimal ra
+%     & mfun_prescript_separator & "ssh_center_b=" & ddecimal (b shifted shadeoffset)
+%     & mfun_prescript_separator & "ssh_radius_b=" & decimal rb
+%     & mfun_prescript_separator & "ssh_nofcolors=" & decimal n
+%     & mfun_prescript_separator & "ssh_domain=" & domstr
+%     & mfun_prescript_separator & "ssh_extend=" & extstr
+%     & mfun_prescript_separator & "ssh_colors=" & colstr
+%     & mfun_prescript_separator & "ssh_bounds=" & bndstr
+%     & mfun_prescript_separator & "ssh_ranges=" & ranstr
+%     ;
+%     mfun_defined_cs
+% enddef ;
 
 % vardef predefined_linear_shade (expr p, n, ca, cb) =
 %     save a, b, sh ; pair a, b ;
@@ -566,53 +695,6 @@ enddef ;
 %     define_circular_shade(ab,ab,0,r,ca,cb)
 % enddef ;
 
-% NEW EXPERIMENTAL CODE
-
-def withlinearshading (expr a, b) =
-    withprescript "sh_type=linear"
-    withprescript "sh_domain=0 1"
-    withprescript "sh_factor="   & decimal shadefactor
-    withprescript "sh_center_a=" & ddecimal (a shifted shadeoffset)
-    withprescript "sh_center_b=" & ddecimal (b shifted shadeoffset)
-enddef ;
-
-def withcircularshading (expr a, b, ra, rb) =
-    withprescript "sh_type=circular"
-    withprescript "sh_domain=0 1"
-    withprescript "sh_factor="   & decimal shadefactor
-    withprescript "sh_center_a=" & ddecimal (a shifted shadeoffset)
-    withprescript "sh_center_b=" & ddecimal (b shifted shadeoffset)
-    withprescript "sh_radius_a=" & decimal ra
-    withprescript "sh_radius_b=" & decimal rb
-enddef ;
-
-def withfromshadecolor expr t =
-    withprescript "sh_color=into"
-    withprescript "sh_color_a=" & colordecimals t
-enddef ;
-
-def withtoshadecolor expr t =
-    withprescript "sh_color=into"
-    withprescript "sh_color_b=" & colordecimals t
-enddef ;
-
-def withshading (expr how)(text rest) =
-    if how = "linear" :
-        withlinearshading(rest)
-    elseif how = "circular" :
-        withcircularshading(rest)
-    else :
-        % nothing
-    fi
-enddef ;
-
-primarydef a shadedinto b =
-    1 % does not work with transparency
-    withprescript "sh_color=into"
-    withprescript "sh_color_a=" & colordecimals a
-    withprescript "sh_color_b=" & colordecimals b
-enddef ;
-
 % Layers
 
 def onlayer primary name =
@@ -657,10 +739,10 @@ enddef ;
 
 % Positions
 
-def register (expr label, width, height, offset) =
+def register (expr tag, width, height, offset) =
 %     draw image (
         addto currentpicture doublepath unitsquare xscaled width yscaled height shifted offset
-            withprescript "ps_label=" & label ;
+            withprescript "ps_label=" & tag ;
 %     ) ; % no transformations
 enddef ;
 
@@ -672,8 +754,8 @@ extra_endfig   := extra_endfig   & "mfun_reset_tex_texts ; " ;
 
 % Bonus
 
-vardef verbatim(expr str) =
-    ditto & "\detokenize{" & str & "}" & ditto
+vardef verbatim(expr s) =
+    ditto & "\detokenize{" & s & "}" & ditto
 enddef ;
 
 % New
@@ -749,7 +831,7 @@ primarydef t asgroup s = % s = isolated|knockout
     endgroup
 enddef ;
 
-% Also experimental
+% Also experimental ... needs to be made better ... so it can change!
 
 string mfun_auto_align[] ;
 
@@ -826,6 +908,10 @@ vardef mfun_cmykcolor_to_string(expr c) =
     decimal blackpart   c
 enddef ;
 
+vardef mfun_greycolor_to_string(expr n) =
+    decimal n
+enddef ;
+
 vardef mfun_path_to_string(expr p) =
     mfun_point_to_string(p,0) for i=1 upto length(p) : & " " & mfun_point_to_string(p,i) endfor
 enddef ;
@@ -852,6 +938,7 @@ vardef tostring(expr value) =
     elseif pair      value : mfun_pair_to_string(value)
     elseif rgbcolor  value : mfun_rgbcolor_to_string(value)
     elseif cmykcolor value : mfun_cmykcolor_to_string(value)
+    elseif greycolor value : mfun_greycolor_to_string(value)
     elseif boolean   value : mfun_boolean_to_string(value)
     elseif path      value : mfun_path_to_string(value)
     elseif transform value : mfun_transform_to_string(value)
@@ -1047,23 +1134,80 @@ enddef ;
 
 % moved here from mp-grap.mpiv
 
+% vardef escaped_format(expr s) =
+%     "" for n=0 upto length(s) : &
+%         if ASCII substring (n,n+1) of s = 37 :
+%             "@"
+%         else :
+%             substring (n,n+1) of s
+%         fi
+%     endfor
+% enddef ;
+
+numeric mfun_esc_b ; % begin
+numeric mfun_esc_l ; % length
+string  mfun_esc_s ; % character
+
+mfun_esc_s := "%" ; % or: char(37)
+
+% this one is the fastest when we have a match
+
+% vardef escaped_format(expr s) =
+%     "" for n=0 upto length(s)-1 : &
+%       % if ASCII substring (n,n+1) of s = 37 :
+%         if substring (n,n+1) of s = mfun_esc_s :
+%             "@"
+%         else :
+%             substring (n,n+1) of s
+%         fi
+%     endfor
+% enddef ;
+
+% this one wins when we have no match
+
 vardef escaped_format(expr s) =
-    "" for n=0 upto length(s) : &
-        if ASCII substring (n,n+1) of s = 37 :
-            "@"
-        else :
-            substring (n,n+1) of s
+    mfun_esc_b := 0 ;
+    mfun_esc_l := length(s) ;
+    for n=0 upto mfun_esc_l-1 :
+      % if ASCII substring (n,n+1) of s = 37 :
+        if substring (n,n+1) of s = mfun_esc_s :
+            if mfun_esc_b = 0 :
+                ""
+            fi
+            if n >= mfun_esc_b :
+                & (substring (mfun_esc_b,n) of s)
+                exitif numeric begingroup mfun_esc_b := n+1 endgroup ; % hide
+            fi
+            & "@"
         fi
     endfor
+    if mfun_esc_b = 0 :
+        s
+  % elseif mfun_esc_b > 0 :
+    elseif mfun_esc_b < mfun_esc_l :
+        & (substring (mfun_esc_b,mfun_esc_l) of s)
+    fi
 enddef ;
 
-vardef strfmt(expr f, x) = % maybe use mfun_ namespace
-    "\MPgraphformat{" & escaped_format(f) & "}{" & mfun_tagged_string(x) & "}"
-enddef ;
-
-vardef varfmt(expr f, x) = % maybe use mfun_ namespace
-    "\MPformatted{" & escaped_format(f) & "}{" & mfun_tagged_string(x) & "}"
-enddef ;
+vardef strfmt(expr f, x) = "\MPgraphformat{" & escaped_format(f) & "}{" & mfun_tagged_string(x) & "}" enddef ;
+vardef varfmt(expr f, x) = "\MPformatted{"   & escaped_format(f) & "}{" & mfun_tagged_string(x) & "}" enddef ;
 
 vardef format   (expr f, x) = textext(strfmt(f, x)) enddef ;
 vardef formatted(expr f, x) = textext(varfmt(f, x)) enddef ;
+
+% could be this (something to discuss with alan as it involves graph):
+%
+% vardef format   (expr f,x) = lua.mp.graphformat(f,mfun_tagged_string(x) enddef ;
+% vardef formatted(expr f,x) = lua.mp.format     (f,                   x) enddef ;
+%
+% def strfmt = format    enddef ; % old
+% def varfmt = formatted enddef ; % old
+
+% new
+
+def eofill text t = fill t withpostscript "evenodd" enddef ;
+%%% eoclip text t = clip t withpostscript "evenodd" enddef ; % no postscripts yet
+
+% def withrule expr r =
+%     if (t = "even-odd") or (t = "evenodd") : withpostscript "evenodd" fi
+% enddef ;
diff --git a/Master/texmf-dist/metapost/context/base/mp-page.mpiv b/Master/texmf-dist/metapost/context/base/mp-page.mpiv
index 9c538d42a65..7a6e576bd98 100644
--- a/Master/texmf-dist/metapost/context/base/mp-page.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-page.mpiv
@@ -11,73 +11,300 @@
 %C therefore copyrighted by \PRAGMA. See mreadme.pdf for
 %C details.
 
-%D This module is rather preliminary and subjected to
-%D changes.
+%D This module is rather preliminary and subjected to changes.
 
 if known context_page : endinput ; fi ;
 
 boolean context_page ; context_page := true ;
 
+% def LoadPageState =
+%     % now always set
+% enddef ;
+%
+% if unknown PageStateAvailable :
+%     boolean PageStateAvailable ;
+%     PageStateAvailable := false ;
+% fi ;
+%
+% if unknown OnRightPage :
+%     boolean OnRightPage ;
+%     OnRightPage := true ;
+% fi ;
+%
+% if unknown OnOddPage :
+%     boolean OnOddPage ;
+%     OnOddPage := true ;
+% fi ;
+%
+% if unknown InPageBody :
+%     boolean InPageBody ;
+%     InPageBody := false ;
+% fi ;
+%
+% string CurrentLayout ;
+%
+% CurrentLayout       := "default" ;
+%
+% PageNumber          := 0 ;
+% PaperHeight         := 845.04684pt  ;
+% PaperWidth          := 597.50787pt  ;
+% PrintPaperHeight    := 845.04684pt  ;
+% PrintPaperWidth     := 597.50787pt  ;
+% TopSpace            :=  71.12546pt  ;
+% BottomSpace         :=   0.0pt      ;
+% BackSpace           :=  71.13275pt  ;
+% CutSpace            :=   0.0pt      ;
+% MakeupHeight        := 711.3191pt   ;
+% MakeupWidth         := 426.78743pt  ;
+% TopHeight           :=   0.0pt      ;
+% TopDistance         :=   0.0pt      ;
+% HeaderHeight        :=  56.90294pt  ;
+% HeaderDistance      :=   0.0pt      ;
+% TextHeight          := 597.51323pt  ;
+% FooterDistance      :=   0.0pt      ;
+% FooterHeight        :=  56.90294pt  ;
+% BottomDistance      :=   0.0pt      ;
+% BottomHeight        :=   0.0pt      ;
+% LeftEdgeWidth       :=   0.0pt      ;
+% LeftEdgeDistance    :=   0.0pt      ;
+% LeftMarginWidth     :=   75.58197pt ;
+% LeftMarginDistance  :=   11.99829pt ;
+% TextWidth           :=  426.78743pt ;
+% RightMarginDistance :=   11.99829pt ;
+% RightMarginWidth    :=   75.58197pt ;
+% RightEdgeDistance   :=    0.0pt     ;
+% RightEdgeWidth      :=    0.0pt     ;
+%
+% PageOffset          :=    0.0pt     ;
+% PageDepth           :=    0.0pt     ;
+%
+% LayoutColumns       :=    0         ;
+% LayoutColumnDistance:=    0.0pt     ;
+% LayoutColumnWidth   :=    0.0pt     ;
+%
+% LeftEdge             :=  -4 ; Top             := -40 ;
+% LeftEdgeSeparator    :=  -3 ; TopSeparator    := -30 ;
+% LeftMargin           :=  -2 ; Header          := -20 ;
+% LeftMarginSeparator  :=  -1 ; HeaderSeparator := -10 ;
+% Text                 :=   0 ; Text            :=   0 ;
+% RightMarginSeparator :=  +1 ; FooterSeparator := +10 ;
+% RightMargin          :=  +2 ; Footer          := +20 ;
+% RightEdgeSeparator   :=  +3 ; BottomSeparator := +30 ;
+% RightEdge            :=  +4 ; Bottom          := +40 ;
+%
+% Margin      := LeftMargin  ; % obsolete
+% Edge        := LeftEdge    ; % obsolete
+% InnerMargin := RightMargin ; % obsolete
+% InnerEdge   := RightEdge   ; % obsolete
+% OuterMargin := LeftMargin  ; % obsolete
+% OuterEdge   := LeftEdge    ; % obsolete
+%
+% InnerMarginWidth     := 0pt ;
+% OuterMarginWidth     := 0pt ;
+% InnerMarginDistance  := 0pt ;
+% OuterMarginDistance  := 0pt ;
+%
+% InnerEdgeWidth     := 0pt ;
+% OuterEdgeWidth     := 0pt ;
+% InnerEdgeDistance  := 0pt ;
+% OuterEdgeDistance  := 0pt ;
+%
+% % path Area[][] ;
+% % pair Location[][] ;
+% % path Field[][] ;
+%
+% % numeric Hstep[] ;
+% % numeric Hsize[] ;
+% % numeric Vstep[] ;
+% % numeric Vsize[] ;
+%
+% path Page ;
+%
+% numeric HorPos ;
+% numeric VerPos ;
+%
+% % for VerPos=Top step 10 until Bottom:
+% %     for HorPos=LeftEdge step 1 until RightEdge:
+% %         Area[HorPos][VerPos] := origin--cycle ;
+% %         Area[VerPos][HorPos] := Area[HorPos][VerPos] ;
+% %         Location[HorPos][VerPos] := origin ;
+% %         Location[VerPos][HorPos] := Location[HorPos][VerPos] ;
+% %         Field[HorPos][VerPos] := origin--cycle ;
+% %         Field[VerPos][HorPos] := Field[HorPos][VerPos] ;
+% %     endfor ;
+% % endfor ;
+%
+% % def LoadPageState =
+% %   scantokens "input mp-state.tmp" ;
+% % enddef ;
+%
+% numeric mfun_temp ;
+%
+% def SwapPageState =
+%     if not OnRightPage :
+%              BackSpace := PaperWidth-MakeupWidth-BackSpace ;
+%               CutSpace := PaperWidth-MakeupWidth-CutSpace ;
+%              mfun_temp := LeftMarginWidth ;
+%        LeftMarginWidth := RightMarginWidth ;
+%       RightMarginWidth := mfun_temp ;
+%              mfun_temp := LeftMarginDistance ;
+%     LeftMarginDistance := RightMarginDistance ;
+%    RightMarginDistance := mfun_temp ;
+%              mfun_temp := LeftEdgeWidth ;
+%          LeftEdgeWidth := RightEdgeWidth ;
+%         RightEdgeWidth := mfun_temp ;
+%              mfun_temp := LeftEdgeDistance ;
+%       LeftEdgeDistance := RightEdgeDistance ;
+%      RightEdgeDistance := mfun_temp ;
+%
+%   % these are now available as ..Width and ..Distance
+%
+%                 Margin := LeftMargin ;
+%                   Edge := LeftEdge ;
+%            InnerMargin := RightMargin ;
+%              InnerEdge := RightEdge ;
+%            OuterMargin := LeftMargin ;
+%              OuterEdge := LeftEdge ;
+%     else :
+%                 Margin := RightMargin ;
+%                   Edge := RightEdge ;
+%            InnerMargin := LeftMargin ;
+%              InnerEdge := LeftEdge ;
+%            OuterMargin := RightMargin ;
+%              OuterEdge := RightEdge ;
+%     fi ;
+% enddef ;
+
+% the new way:
+
+def LoadPageState =
+    % now always set
+enddef ;
+
 if unknown PageStateAvailable :
     boolean PageStateAvailable ;
     PageStateAvailable := false ;
 fi ;
 
-if unknown OnRightPage :
-    boolean OnRightPage ;
-    OnRightPage := true ;
-fi ;
+string CurrentLayout ; CurrentLayout := "default" ;
+
+vardef PaperHeight          = lua.mp.PaperHeight         () enddef ;
+vardef PaperWidth           = lua.mp.PaperWidth          () enddef ;
+vardef PrintPaperHeight     = lua.mp.PrintPaperHeight    () enddef ;
+vardef PrintPaperWidth      = lua.mp.PrintPaperWidth     () enddef ;
+vardef TopSpace             = lua.mp.TopSpace            () enddef ;
+vardef BottomSpace          = lua.mp.BottomSpace         () enddef ;
+vardef BackSpace            = lua.mp.BackSpace           () enddef ;
+vardef CutSpace             = lua.mp.CutSpace            () enddef ;
+vardef MakeupHeight         = lua.mp.MakeupHeight        () enddef ;
+vardef MakeupWidth          = lua.mp.MakeupWidth         () enddef ;
+vardef TopHeight            = lua.mp.TopHeight           () enddef ;
+vardef TopDistance          = lua.mp.TopDistance         () enddef ;
+vardef HeaderHeight         = lua.mp.HeaderHeight        () enddef ;
+vardef HeaderDistance       = lua.mp.HeaderDistance      () enddef ;
+vardef TextHeight           = lua.mp.TextHeight          () enddef ;
+vardef FooterDistance       = lua.mp.FooterDistance      () enddef ;
+vardef FooterHeight         = lua.mp.FooterHeight        () enddef ;
+vardef BottomDistance       = lua.mp.BottomDistance      () enddef ;
+vardef BottomHeight         = lua.mp.BottomHeight        () enddef ;
+vardef LeftEdgeWidth        = lua.mp.LeftEdgeWidth       () enddef ;
+vardef LeftEdgeDistance     = lua.mp.LeftEdgeDistance    () enddef ;
+vardef LeftMarginWidth      = lua.mp.LeftMarginWidth     () enddef ;
+vardef LeftMarginDistance   = lua.mp.LeftMarginDistance  () enddef ;
+vardef TextWidth            = lua.mp.TextWidth           () enddef ;
+vardef RightMarginDistance  = lua.mp.RightMarginDistance () enddef ;
+vardef RightMarginWidth     = lua.mp.RightMarginWidth    () enddef ;
+vardef RightEdgeDistance    = lua.mp.RightEdgeDistance   () enddef ;
+vardef RightEdgeWidth       = lua.mp.RightEdgeWidth      () enddef ;
+vardef InnerMarginDistance  = lua.mp.InnerMarginDistance () enddef ;
+vardef InnerMarginWidth     = lua.mp.InnerMarginWidth    () enddef ;
+vardef OuterMarginDistance  = lua.mp.OuterMarginDistance () enddef ;
+vardef OuterMarginWidth     = lua.mp.OuterMarginWidth    () enddef ;
+vardef InnerEdgeDistance    = lua.mp.InnerEdgeDistance   () enddef ;
+vardef InnerEdgeWidth       = lua.mp.InnerEdgeWidth      () enddef ;
+vardef OuterEdgeDistance    = lua.mp.OuterEdgeDistance   () enddef ;
+vardef OuterEdgeWidth       = lua.mp.OuterEdgeWidth      () enddef ;
+vardef PageOffset           = lua.mp.PageOffset          () enddef ;
+vardef PageDepth            = lua.mp.PageDepth           () enddef ;
+vardef LayoutColumns        = lua.mp.LayoutColumns       () enddef ;
+vardef LayoutColumnDistance = lua.mp.LayoutColumnDistance() enddef ;
+vardef LayoutColumnWidth    = lua.mp.LayoutColumnWidth   () enddef ;
+
+vardef OnRightPage          = lua.mp.OnRightPage         () enddef ;
+vardef OnOddPage            = lua.mp.OnOddPage           () enddef ;
+vardef InPageBody           = lua.mp.InPageBody          () enddef ;
+
+vardef RealPageNumber       = lua.mp.RealPageNumber      () enddef ;
+vardef PageNumber           = lua.mp.PageNumber          () enddef ;
+vardef NOfPages             = lua.mp.NOfPages            () enddef ;
+vardef LastPageNumber       = lua.mp.LastPageNumber      () enddef ; % duplicates
+
+vardef CurrentColumn        = lua.mp.CurrentColumn       () enddef ;
+vardef NOfColumns           = lua.mp.NOfColumns          () enddef ;
+
+vardef BaseLineSkip         = lua.mp.BaseLineSkip        () enddef ;
+vardef LineHeight           = lua.mp.LineHeight          () enddef ;
+vardef BodyFontSize         = lua.mp.BodyFontSize        () enddef ;
+
+vardef TopSkip              = lua.mp.TopSkip             () enddef ;
+vardef StrutHeight          = lua.mp.StrutHeight         () enddef ;
+vardef StrutDepth           = lua.mp.StrutDepth          () enddef ;
+
+vardef CurrentWidth         = lua.mp.CurrentWidth        () enddef ;
+vardef CurrentHeight        = lua.mp.CurrentHeight       () enddef ;
+
+vardef HSize                = lua.mp.HSize               () enddef ; % duplicates
+vardef VSize                = lua.mp.VSize               () enddef ; % duplicates
+
+vardef EmWidth              = lua.mp.EmWidth             () enddef ;
+vardef ExHeight             = lua.mp.ExHeight            () enddef ;
+
+vardef PageFraction         = lua.mp.PageFraction        () enddef ;
+
+vardef SpineWidth           = lua.mp.SpineWidth          () enddef ;
+vardef PaperBleed           = lua.mp.PaperBleed          () enddef ;
+
+boolean mfun_swapped ;
 
-if unknown OnOddPage :
-    boolean OnOddPage ;
-    OnOddPage := true ;
-fi ;
+def SwapPageState =
+    mfun_swapped := true ;
+enddef ;
 
-if unknown InPageBody :
-    boolean InPageBody ;
-    InPageBody := false ;
-fi ;
+extra_beginfig := extra_beginfig & "mfun_swapped := false ;" ;
+
+vardef BackSpace = if (mfun_swapped and not OnRightPage) : PaperWidth - MakeupWidth - fi  lua.mp.BackSpace() enddef ;
+vardef CutSpace  = if (mfun_swapped and not OnRightPage) : PaperWidth - MakeupWidth - fi  lua.mp.CutSpace () enddef ;
+
+vardef LeftMarginWidth     = if mfun_swapped and not OnRightPage : lua.mp.RightMarginWidth   () else : lua.mp.LeftMarginWidth    () fi enddef ;
+vardef RightMarginWidth    = if mfun_swapped and not OnRightPage : lua.mp.LeftMarginWidth    () else : lua.mp.RightMarginWidth   () fi enddef ;
+vardef LeftMarginDistance  = if mfun_swapped and not OnRightPage : lua.mp.RightMarginDistance() else : lua.mp.LeftMarginDistance () fi enddef ;
+vardef RightMarginDistance = if mfun_swapped and not OnRightPage : lua.mp.LeftMarginDistance () else : lua.mp.RightMarginDistance() fi enddef ;
+vardef LeftEdgeWidth       = if mfun_swapped and not OnRightPage : lua.mp.RightEdgeWidth     () else : lua.mp.LeftEdgeWidth      () fi enddef ;
+vardef RightEdgeWidth      = if mfun_swapped and not OnRightPage : lua.mp.LeftEdgeWidth      () else : lua.mp.RightEdgeWidth     () fi enddef ;
+vardef LeftEdgeDistance    = if mfun_swapped and not OnRightPage : lua.mp.RightEdgeDistance  () else : lua.mp.LeftEdgeDistance   () fi enddef ;
+vardef RightEdgeDistance   = if mfun_swapped and not OnRightPage : lua.mp.LeftEdgeDistance   () else : lua.mp.RightEdgeDistance  () fi enddef ;
+
+% vardef Margin      = if OnRightPage : lua.mp.RightMarginWidth else : lua.mp.LeftMarginWidth  fi enddef ;
+% vardef Edge        = if OnRightPage : lua.mp.RightEdgeWidth   else : lua.mp.LeftEdgeWidth    fi enddef ;
+% vardef InnerMargin = if OnRightPage : lua.mp.LeftMarginWidth  else : lua.mp.RightMarginWidth fi enddef ;
+% vardef InnerEdge   = if OnRightPage : lua.mp.LeftEdgeWidth    else : lua.mp.RightEdgeWidth   fi enddef ;
+% vardef OuterMargin = if OnRightPage : lua.mp.RightMarginWidth else : lua.mp.LeftMarginWidth  fi enddef ;
+% vardef OuterEdge   = if OnRightPage : lua.mp.RightEdgeWidth   else : lua.mp.LeftEdgeWidth    fi enddef ;
+
+% vardef CurrentLayout = lua.mp.CurrentLayout () enddef ;
 
-string CurrentLayout ;
-
-CurrentLayout       := "default" ;
-
-PageNumber          := 0 ;
-PaperHeight         := 845.04684pt  ;
-PaperWidth          := 597.50787pt  ;
-PrintPaperHeight    := 845.04684pt  ;
-PrintPaperWidth     := 597.50787pt  ;
-TopSpace            :=  71.12546pt  ;
-BottomSpace         :=   0.0pt      ;
-BackSpace           :=  71.13275pt  ;
-CutSpace            :=   0.0pt      ;
-MakeupHeight        := 711.3191pt   ;
-MakeupWidth         := 426.78743pt  ;
-TopHeight           :=   0.0pt      ;
-TopDistance         :=   0.0pt      ;
-HeaderHeight        :=  56.90294pt  ;
-HeaderDistance      :=   0.0pt      ;
-TextHeight          := 597.51323pt  ;
-FooterDistance      :=   0.0pt      ;
-FooterHeight        :=  56.90294pt  ;
-BottomDistance      :=   0.0pt      ;
-BottomHeight        :=   0.0pt      ;
-LeftEdgeWidth       :=   0.0pt      ;
-LeftEdgeDistance    :=   0.0pt      ;
-LeftMarginWidth     :=   75.58197pt ;
-LeftMarginDistance  :=   11.99829pt ;
-TextWidth           :=  426.78743pt ;
-RightMarginDistance :=   11.99829pt ;
-RightMarginWidth    :=   75.58197pt ;
-RightEdgeDistance   :=    0.0pt     ;
-RightEdgeWidth      :=    0.0pt     ;
-
-PageOffset          :=    0.0pt     ;
-PageDepth           :=    0.0pt     ;
-
-LayoutColumns       :=    0         ;
-LayoutColumnDistance:=    0.0pt     ;
-LayoutColumnWidth   :=    0.0pt     ;
+vardef OverlayWidth      = lua.mp.OverlayWidth    ()  enddef ;
+vardef OverlayHeight     = lua.mp.OverlayHeight   ()  enddef ;
+vardef OverlayDepth      = lua.mp.OverlayDepth    ()  enddef ;
+vardef OverlayLineWidth  = lua.mp.OverlayLineWidth()  enddef ;
+vardef OverlayOffset     = lua.mp.OverlayOffset   ()  enddef ;
+
+vardef defaultcolormodel = lua.mp.defaultcolormodel() enddef ;
+
+%  def OverlayLineColor  = lua.mp.OverlayLineColor()  enddef ;
+%  def OverlayColor      = lua.mp.OverlayColor    ()  enddef ;
+
+% Next we implement the the page area model. First some constants.
 
 LeftEdge             :=  -4 ; Top             := -40 ;
 LeftEdgeSeparator    :=  -3 ; TopSeparator    := -30 ;
@@ -89,37 +316,28 @@ RightMargin          :=  +2 ; Footer          := +20 ;
 RightEdgeSeparator   :=  +3 ; BottomSeparator := +30 ;
 RightEdge            :=  +4 ; Bottom          := +40 ;
 
-Margin      := LeftMargin  ; % obsolete
-Edge        := LeftEdge    ; % obsolete
-InnerMargin := RightMargin ; % obsolete
-InnerEdge   := RightEdge   ; % obsolete
-OuterMargin := LeftMargin  ; % obsolete
-OuterEdge   := LeftEdge    ; % obsolete
+% Margin      := LeftMargin  ; % obsolete
+% Edge        := LeftEdge    ; % obsolete
+% InnerMargin := RightMargin ; % obsolete
+% InnerEdge   := RightEdge   ; % obsolete
+% OuterMargin := LeftMargin  ; % obsolete
+% OuterEdge   := LeftEdge    ; % obsolete
 
-InnerMarginWidth     := 0pt ;
-OuterMarginWidth     := 0pt ;
-InnerMarginDistance  := 0pt ;
-OuterMarginDistance  := 0pt ;
+numeric HorPos ; HorPos := 0 ;
+numeric VerPos ; VerPos := 0 ;
 
-InnerEdgeWidth     := 0pt ;
-OuterEdgeWidth     := 0pt ;
-InnerEdgeDistance  := 0pt ;
-OuterEdgeDistance  := 0pt ;
+% We used to initialize these variables each (sub)run but at some point MP
+% became too slow for this. See later.
 
 % path Area[][] ;
 % pair Location[][] ;
 % path Field[][] ;
-
+%
 % numeric Hstep[] ;
 % numeric Hsize[] ;
 % numeric Vstep[] ;
 % numeric Vsize[] ;
-
-path Page ;
-
-numeric HorPos ;
-numeric VerPos ;
-
+%
 % for VerPos=Top step 10 until Bottom:
 %     for HorPos=LeftEdge step 1 until RightEdge:
 %         Area[HorPos][VerPos] := origin--cycle ;
@@ -130,46 +348,8 @@ numeric VerPos ;
 %         Field[VerPos][HorPos] := Field[HorPos][VerPos] ;
 %     endfor ;
 % endfor ;
-
-% def LoadPageState =
-%   scantokens "input mp-state.tmp" ;
-% enddef ;
-
-def SwapPageState =
-    if not OnRightPage :
-             BackSpace := PaperWidth-MakeupWidth-BackSpace ;
-              CutSpace := PaperWidth-MakeupWidth-CutSpace ;
-                     i := LeftMarginWidth ;
-       LeftMarginWidth := RightMarginWidth ;
-      RightMarginWidth := i ;
-                     i := LeftMarginDistance ;
-    LeftMarginDistance := RightMarginDistance ;
-   RightMarginDistance := i ;
-                     i := LeftEdgeWidth ;
-         LeftEdgeWidth := RightEdgeWidth ;
-        RightEdgeWidth := i ;
-                     i := LeftEdgeDistance ;
-      LeftEdgeDistance := RightEdgeDistance ;
-     RightEdgeDistance := i ;
-
-  % these are now available as ..Width and ..Distance
-
-                Margin := LeftMargin ;
-                  Edge := LeftEdge ;
-           InnerMargin := RightMargin ;
-             InnerEdge := RightEdge ;
-           OuterMargin := LeftMargin ;
-             OuterEdge := LeftEdge ;
-    else :
-                Margin := RightMargin ;
-                  Edge := RightEdge ;
-           InnerMargin := LeftMargin ;
-             InnerEdge := LeftEdge ;
-           OuterMargin := RightMargin ;
-             OuterEdge := RightEdge ;
-    fi ;
-enddef ;
-
+%
+%
 % def SetPageAreas =
 %
 %     numeric Vsize[], Hsize[], Vstep[], Hstep[] ;
@@ -338,29 +518,55 @@ def SetPageField =
     endfor ;
 enddef ;
 
-def SetPagePage =
-    path Page ;
-    Page := unitsquare xscaled PaperWidth yscaled PaperHeight ;
+def mfun_page_Area      = hide(SetPageArea     ;) Area      enddef ;
+def mfun_page_Location  = hide(SetPageLocation ;) Location  enddef ;
+def mfun_page_Field     = hide(SetPageField    ;) Field     enddef ;
+def mfun_page_Vsize     = hide(SetPageVsize    ;) Vsize     enddef ;
+def mfun_page_Hsize     = hide(SetPageHsize    ;) Hsize     enddef ;
+def mfun_page_Vstep     = hide(SetPageVstep    ;) Vstep     enddef ;
+def mfun_page_Hstep     = hide(SetPageHstep    ;) Hstep     enddef ;
+
+def SetAreaVariables =
+    let Area      = mfun_page_Area ;
+    let Location  = mfun_page_Location ;
+    let Field     = mfun_page_Field ;
+    let Vsize     = mfun_page_Vsize ;
+    let Hsize     = mfun_page_Hsize ;
+    let Vstep     = mfun_page_Vstep ;
+    let Hstep     = mfun_page_Hstep ;
 enddef ;
 
-def mfun_page_Area     = hide(SetPageArea     ;) Area     enddef ;
-def mfun_page_Location = hide(SetPageLocation ;) Location enddef ;
-def mfun_page_Field    = hide(SetPageField    ;) Field    enddef ;
-def mfun_page_Vsize    = hide(SetPageVsize    ;) Vsize    enddef ;
-def mfun_page_Hsize    = hide(SetPageHsize    ;) Hsize    enddef ;
-def mfun_page_Vstep    = hide(SetPageVstep    ;) Vstep    enddef ;
-def mfun_page_Hstep    = hide(SetPageHstep    ;) Hstep    enddef ;
-def mfun_page_Page     = hide(SetPagePage     ;) Page     enddef ;
+% we should make Page no path .. from now on don't assume this .. for a while we keek it
+
+vardef FrontPageWidth  = PaperWidth enddef ;
+vardef BackPageWidth   = PaperWidth enddef ;
+vardef CoverWidth      = 2 * PaperWidth + SpineWidth enddef ;
+vardef CoverHeight     = PaperHeight enddef ;
+
+vardef FrontPageHeight = PaperHeight enddef ;
+vardef BackPageHeight  = PaperHeight enddef ;
+vardef SpineHeight     = PaperHeight enddef ;
+
+def SetPagePage      = path Page      ; Page      := unitsquare xscaled PaperWidth      yscaled PaperHeight ; enddef ;
+def SetPageCoverPage = path CoverPage ; CoverPage := unitsquare xscaled CoverWidth      yscaled CoverHeight ; enddef ;
+def SetPageSpine     = path Spine     ; Spine     := unitsquare xscaled SpineWidth      yscaled CoverHeight shifted (BackPageWidth,0) ; enddef ;
+def SetPageBackPage  = path BackPage  ; BackPage  := unitsquare xscaled BackPageWidth   yscaled CoverHeight ; enddef ;
+def SetPageFrontPage = path FrontPage ; FrontPage := unitsquare xscaled FrontPageWidth  yscaled CoverHeight shifted (BackPageWidth+SpineWidth,0) ; enddef ;
+
+def mfun_page_Page      = hide(SetPagePage     ;) Page      enddef ;
+def mfun_page_CoverPage = hide(SetPageCoverPage;) CoverPage enddef ;
+def mfun_page_Spine     = hide(SetPageSpine    ;) Spine     enddef ;
+def mfun_page_BackPage  = hide(SetPageBackPage ;) BackPage  enddef ;
+def mfun_page_FrontPage = hide(SetPageFrontPage;) FrontPage enddef ;
 
 def SetPageVariables =
-    let Area     = mfun_page_Area     ;
-    let Location = mfun_page_Location ;
-    let Field    = mfun_page_Field    ;
-    let Vsize    = mfun_page_Vsize    ;
-    let Hsize    = mfun_page_Hsize    ;
-    let Vstep    = mfun_page_Vstep    ;
-    let Hstep    = mfun_page_Hstep    ;
-    let Page     = mfun_page_Page     ;
+    SetAreaVariables ;
+    %
+    let Page      = mfun_page_Page ;
+    let CoverPage = mfun_page_CoverPage ;
+    let Spine     = mfun_page_Spine ;
+    let BackPage  = mfun_page_BackPage ;
+    let FrontPage = mfun_page_FrontPage ;
 enddef ;
 
 SetPageVariables ;
@@ -393,45 +599,10 @@ enddef ;
 
 def BoundCoverAreas =
     % todo: add cropmarks
-    bboxmargin := 0 ; setbounds currentpicture to Paper enlarged PaperBleed ;
+    bboxmargin := 0 ; setbounds currentpicture to CoverPage enlarged PaperBleed ;
 enddef ;
 
-def SetCoverAreas =
-
-    if unknown SpineWidth :
-        SpineWidth := 8mm ;
-    fi ;
-
-    if unknown PaperBleed :
-        PaperBleed := 0 ;
-    fi ;
-
-    FrontPageWidth  := PaperWidth ;
-    BackPageWidth   := PaperWidth ;
-    PaperWidth      := 2 * PaperWidth + SpineWidth ;
-
-    FrontPageHeight := PaperHeight ;
-    BackPageHeight  := PaperHeight ;
-    PaperHeight     := PaperHeight ;
-    SpineHeight     := PaperHeight ;
-
-    path Paper     ; Paper     := unitsquare xscaled PaperWidth      yscaled PaperHeight ;
-    path Spine     ; Spine     := unitsquare xscaled SpineWidth      yscaled PaperHeight shifted (BackPageWidth,0);
-    path BackPage  ; BackPage  := unitsquare xscaled BackPageWidth   yscaled PaperHeight ;
-    path FrontPage ; FrontPage := unitsquare xscaled FrontPageWidth  yscaled PaperHeight shifted (BackPageWidth+SpineWidth,0) ;
-
-enddef ;
-
-% def StartCover =
-%     begingroup ;
-%     if PageStateAvailable :
-%         LoadPageState ;
-%      %  SwapPageState ;
-%     fi ;
-%     SetPageAreas ;
-%     SetCoverAreas ;
-%     BoundCoverAreas ;
-% enddef ;
+let SetCoverAreas = SetPageVariables ;  % compatiblity
 
 def StartCover =
     begingroup ;
diff --git a/Master/texmf-dist/metapost/context/base/mp-tool.mpii b/Master/texmf-dist/metapost/context/base/mp-tool.mpii
index 62bd122f590..a5bb345a1a3 100644
--- a/Master/texmf-dist/metapost/context/base/mp-tool.mpii
+++ b/Master/texmf-dist/metapost/context/base/mp-tool.mpii
@@ -1407,7 +1407,7 @@ primarydef pct along pat = % also negative
 enddef ;
 
 primarydef len on pat = % no outer ( ) .. somehow fails
-    (arctime if len>0 : len else : (arclength(pat)+len) fi of pat) of pat
+    (arctime if len>=0 : len else : (arclength(pat)+len) fi of pat) of pat
 enddef ;
 
 % this cuts of a piece from both ends
diff --git a/Master/texmf-dist/metapost/context/base/mp-tool.mpiv b/Master/texmf-dist/metapost/context/base/mp-tool.mpiv
index 7845467a46c..e497e2f7242 100644
--- a/Master/texmf-dist/metapost/context/base/mp-tool.mpiv
+++ b/Master/texmf-dist/metapost/context/base/mp-tool.mpiv
@@ -57,8 +57,15 @@ mpprocset    := 1 ;
 %
 % protect ;
 
-string space ; space := char 32 ;
-string CRLF  ; CRLF  := char 10 & char 13 ;
+string space   ; space   := char 32 ;
+string percent ; percent := char 37 ;
+string crlf    ; crlf    := char 10 & char 13 ;
+string dquote  ; dquote  := char 34 ;
+
+let SPACE   = space ;
+let CRLF    = crlf ;
+let DQUOTE  = dquote ;
+let PERCENT = percent ;
 
 vardef ddecimal primary p =
     decimal xpart p & " " & decimal ypart p
@@ -90,8 +97,8 @@ newinternal graycolormodel ; graycolormodel := 3 ;
 newinternal rgbcolormodel  ; rgbcolormodel  := 5 ;
 newinternal cmykcolormodel ; cmykcolormodel := 7 ;
 
-let grayscale = numeric ;
-let greyscale = numeric ;
+let grayscale = graycolor ;
+let greyscale = greycolor ;
 
 vardef colorpart expr c =
     if not picture c :
@@ -141,6 +148,39 @@ vardef colordecimals primary c =
     fi
 enddef ;
 
+vardef colordecimalslist(text t) =
+    save b ; boolean b ; b := false ;
+    for s=t :
+        if b : & " " & fi
+        colordecimals(s)
+        hide(b := true ;)
+    endfor
+enddef ;
+
+% vardef _ctx_color_spec_ primary c =
+%     if cmykcolor c  :
+%          "c=" & decimal cyanpart    c &
+%         ",m=" & decimal magentapart c &
+%         ",y=" & decimal yellowpart  c &
+%         ",k=" & decimal blackpart   c
+%     elseif rgbcolor c :
+%          "r=" & decimal redpart   c &
+%         ",g=" & decimal greenpart c &
+%         ",b=" & decimal bluepart  c
+%     else :
+%          "s=" & decimal c
+%     fi
+% enddef ;
+%
+% vardef _ctx_color_spec_list_(text t) =
+%     save b ; boolean b ; b := false ;
+%     for s=t :
+%         if b : & " " & fi
+%         _ctx_color_spec_(s)
+%         hide(b := true ;)
+%     endfor
+% enddef ;
+
 %D We have standardized data file names:
 
 def job_name =
@@ -152,7 +192,8 @@ def data_mpd_file =
 enddef ;
 
 %D Because \METAPOST\ has a hard coded limit of 4~datafiles,
-%D we need some trickery when we have multiple files.
+%D we need some trickery when we have multiple files. This will
+%D be redone (via \LUA).
 
 if unknown collapse_data :
     boolean collapse_data ;
@@ -292,12 +333,12 @@ enddef;
 %D Some missing functions can be implemented rather straightforward (thanks to
 %D Taco and others):
 
-pi := 3.14159265358979323846 ; radian := 180/pi ; % 2pi*radian = 360 ;
+% oldpi := 3.14159265358979323846 ; % from <math.h>
+pi      := 3.14159265358979323846264338327950288419716939937510 ; % 50 digits
+radian  := 180/pi ; % 2pi*radian = 360 ;
 
 % let +++ = ++ ;
 
-numeric Pi ; Pi := pi ; % for some old compatibility reasons i guess
-
 vardef sqr  primary x = x*x                                 enddef ;
 vardef log  primary x = if x=0: 0 else: mlog(x)/mlog(10) fi enddef ;
 vardef ln   primary x = if x=0: 0 else: mlog(x)/256 fi      enddef ;
@@ -328,6 +369,11 @@ vardef asinh  primary x = ln(x+(x++1))     enddef ;
 vardef sinh   primary x = save xx ; xx = exp x ; (xx-1/xx)/2 enddef ;
 vardef cosh   primary x = save xx ; xx = exp x ; (xx+1/xx)/2 enddef ;
 
+%D Like mod, but useful for anglesl it returns (-.5d,+.5d] and is used
+%D in for instance mp-chem.
+
+primarydef a zmod b = (-((b/2 - a) mod b) + b/2) enddef ;
+
 %D Sometimes this is handy:
 
 def undashed =
@@ -774,8 +820,8 @@ vardef whitecolor(expr c) =
     if cmykcolor c : (0,0,0,0) elseif rgbcolor c : (1,1,1)  else : 1         fi
 enddef ;
 
-vardef blackcolor(expr c) =
-    if cmykcolor c : (0,0,0,1) elseif rgbcolor c : (0,0,0)  else : 0         fi
+vardef blackcolor expr c =
+    if cmykcolor c : (0,0,0,1) elseif rgbcolor c : (0,0,0)  else : 0 fi
 enddef ;
 
 %D Well, this is the dangerous and naive version:
@@ -1324,7 +1370,7 @@ primarydef pct along pat = % also negative
 enddef ;
 
 primarydef len on pat = % no outer ( ) .. somehow fails
-    (arctime if len>0 : len else : (arclength(pat)+len) fi of pat) of pat
+    (arctime if len>=0 : len else : (arclength(pat)+len) fi of pat) of pat
 enddef ;
 
 % this cuts of a piece from both ends
@@ -1545,9 +1591,13 @@ primarydef p softened c =
 enddef ;
 
 vardef grayed primary p =
-    if color p :
+    if rgbcolor p :
         tripled(.30redpart p+.59greenpart p+.11bluepart p)
-    else :
+    elseif cmykcolor p :
+        tripled(.30*(1-cyanpart i)+.59*(1-magentapart i)+.11*(1-yellowpart i)+blackpart i)
+    elseif greycolor p :
+        p
+    elseif picture p :
         image (
             for i within p :
                 addto currentpicture
@@ -1563,12 +1613,24 @@ vardef grayed primary p =
                     else :
                         also i
                     fi
-                withcolor tripled(.30redpart i+.59greenpart i+.11bluepart i) ;
+                if unknown colorpart i :
+                    % nothing
+                elseif rgbcolor colorpart i :
+                    withcolor tripled(.30redpart i+.59greenpart i+.11bluepart i) ;
+                elseif cmykcolor colorpart i :
+                    withcolor tripled(.30*(1-cyanpart i)+.59*(1-magentapart i)+.11*(1-yellowpart i)+blackpart i) ;
+                else :
+                    withcolor colorpart i ;
+                fi
             endfor ;
         )
-  fi
+    else :
+        p
+    fi
 enddef ;
 
+let greyed = grayed ;
+
 % yes or no: "text" infont "cmr12" at 24pt ;
 
 % let normalinfont = infont ;
@@ -2036,7 +2098,7 @@ enddef ;
 % handy
 
 def withgray primary g =
-    withcolor (g,g,g)
+    withcolor g
 enddef ;
 
 % for metafun
@@ -2259,7 +2321,7 @@ enddef ;
 %D Handy:
 
 def break =
-    exitif true fi ;
+    exitif true ; % fi
 enddef ;
 
 %D New too:
@@ -2272,23 +2334,31 @@ primarydef p ystretched h = (
     p if (bbheight(p)>0) and (h>0) : yscaled (h/bbheight(p)) fi
 ) enddef ;
 
-primarydef p snapped s =
-    hide (
-        if path p :
-            forever :
-                exitif (bbheight(p) <= s) and (bbwidth(p) <= s) ;
-                p := p scaled (1/2) ;
-            endfor ;
-        elseif numeric p :
-            forever :
-                exitif p <= s ;
-                p := p scaled (1/2) ;
-            endfor ;
-        fi ;
-    )
-    p
+%D Newer:
+
+vardef area expr p =
+    % we could calculate the boundingbox once
+    (xpart llcorner boundingbox p,0) -- p --
+    (xpart lrcorner boundingbox p,0) -- cycle
 enddef ;
 
+vardef basiccolors[] =
+    if @ = 0 :
+        white
+    else :
+        save n ; n := @ mod 7 ;
+        if     n = 1 : red
+        elseif n = 2 : green
+        elseif n = 3 : blue
+        elseif n = 4 : cyan
+        elseif n = 5 : magenta
+        elseif n = 6 : yellow
+        else         : black
+        fi
+    fi
+enddef ;
+
+
 % vardef somecolor = (1,1,0,0) enddef ;
 
 % fill OverlayBox withcolor (rcomponent somecolor,gcomponent somecolor,bcomponent somecolor) ;
@@ -2335,7 +2405,6 @@ vardef undecorated (text imagedata) text decoration =
     currentpicture
 enddef ;
 
-
 if metapostversion < 1.770  :
 
     vardef decorated (text imagedata) text decoration =
@@ -2455,25 +2524,76 @@ enddef ;
 %     )
 % enddef ;
 
+vardef mfun_snapped(expr p, s) =
+    if p < 0 : - ( - else : ( fi p div s) * s % the less tokens the better
+enddef ;
+
+vardef mfun_applied(expr p, s)(suffix a) =
+    if path p :
+        if pair s :
+            for i=0 upto length(p)-1 :
+                (a(xpart point i of p,xpart s),a(ypart point i of p,ypart s)) --
+            endfor
+            if cycle p :
+                cycle
+            else :
+                (a(xpart point length(p) of p,xpart s),a(ypart point length(p) of p,ypart s))
+            fi
+        else :
+            for i=0 upto length(p)-1 :
+                (a(xpart point i of p,s),a(ypart point i of p,s)) --
+            endfor
+            if cycle p :
+                cycle
+            else :
+                (a(xpart point length(p) of p,s),a(ypart point length(p) of p,s))
+            fi
+        fi
+    elseif pair p :
+        if pair s :
+            (a(xpart p,xpart s),a(ypart p,ypart s))
+        else :
+            (a(xpart p,s),a(ypart p,s))
+        fi
+    elseif cmykcolor p :
+       (a(cyanpart p,s),a(magentapart p,s),a(yellowpart p,s),a(blackpart p,s))
+    elseif rgbcolor p :
+       (a(redpart p,s),a(greenpart p,s),a(bluepart p,s))
+    elseif graycolor p :
+        a(p,s)
+    elseif numeric p :
+        a(p,s)
+    else
+        p
+    fi
+enddef ;
+
+primarydef p snapped s =
+    mfun_applied(p,s)(mfun_snapped) % so we can play with variants
+enddef ;
+
 %D New helpers:
 
+newinternal charscale ; charscale := 1 ; % persistent so one needs to 'reset' it to 0 or 1
+
 def beginglyph(expr unicode, width, height, depth) =
     beginfig(unicode) ; % the number is irrelevant
     charcode := unicode ;
     charwd   := width ;
     charht   := height ;
     chardp   := depth ;
+  % charscale := 1 ; % can be set for a whole font, so no reset here
 enddef ;
 
 def endglyph =
     setbounds currentpicture to (boundingbox unitsquare xscaled charwd yscaled (charht + chardp) shifted (0,-chardp)) ;
-    if known charscale :
+    if known charscale : if (charscale > 0) and (charscale <> 1) :
         currentpicture := currentpicture scaled charscale ;
-    fi ;
+    fi ; fi ;
     endfig ;
 enddef ;
 
-%D Dimensions have bever been an issue as traditional MP can't make that large
+%D Dimensions have never been an issue as traditional MP can't make that large
 %D pictures, but with double mode we need a catch:
 
 newinternal maxdimensions ; maxdimensions := 14000 ;