2020-12-15 10:12:00

1 files changed, 291 insertions, 0 deletions

diff --git a/metapost/context/base/mpxl/mp-abck.mpxl b/metapost/context/base/mpxl/mp-abck.mpxl
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+%D \module
+%D   [       file=mp-abck.mpiv,
+%D        version=2012.02.19, % was mp-core: 1999.08.01, anchoring
+%D          title=\CONTEXT\ \METAPOST\ graphics,
+%D       subtitle=anchored background macros,
+%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 mreadme.pdf for
+%C details.
+
+if known context_abck : endinput ; fi ;
+
+boolean context_abck ; context_abck := true ; immutable context_abck ;
+
+path    multiregs[],    % region used for multipar (tracing only)
+        multipars[],    % effective area (shape)
+        multibox ;      % main boundingbox (of main region)
+
+string  multikind[] ;   % region state: single | first | middle | last (new method)
+
+numeric multilocs[],    % 1=begin 2=between 3=end (old method)
+        nofmultipars ;  % number of calculated areas
+
+numeric par_strut_height,
+        par_strut_depth,
+        par_line_height ;
+
+nofmultipars     := 0 ;
+par_strut_height := 0 ;
+par_strut_depth  := 0 ;
+par_line_height  := 0 ;
+
+def boxgridoptions = withcolor .8red   enddef ;
+def boxlineoptions = withcolor .8blue  enddef ;
+def boxfilloptions = withcolor .8white enddef ;
+
+numeric boxgridtype      ; boxgridtype      := 0 ;
+numeric boxlinetype      ; boxlinetype      := 1 ;
+numeric boxfilltype      ; boxfilltype      := 1 ;
+numeric boxdashtype      ; boxdashtype      := 0 ;
+pair    boxgriddirection ; boxgriddirection := up ;
+numeric boxgridwidth     ; boxgridwidth     := 1pt ;
+numeric boxlinewidth     ; boxlinewidth     := 1pt ;
+numeric boxlineradius    ; boxlineradius    := 0 ;
+numeric boxlineoffset    ; boxlineoffset    := 0 ;
+numeric boxfilloffset    ; boxfilloffset    := 0 ;
+numeric boxgriddistance  ; boxgriddistance  := .5cm ;
+numeric boxgridshift     ; boxgridshift     := 0 ;
+
+permanent multipars, multiregs, multibox, multikind, multilocs, nofmultipars ;
+
+vardef abck_draw_path(expr p) =
+    if (length p > 2) and (bbwidth(p) > 1) and (bbheight(p) > 1) :
+        save pp ; path pp ;
+        pp := p if (boxlineradius>0) and (boxlinetype=2) : cornered boxlineradius fi ;
+        if boxfilltype > 0 :
+            if boxfilloffset > 0 :
+                interim linejoin := mitered ;
+                filldraw pp boxfilloptions withpen pencircle scaled (2*boxfilloffset) ;
+            else :
+                fill pp boxfilloptions ;
+            fi ;
+        fi ;
+        if boxlinetype > 0 :
+            draw pp boxlineoptions withpen pencircle scaled boxlinewidth ;
+        fi ;
+    fi ;
+enddef ;
+
+def abck_grid_line(expr start, width) =
+    % 1 = normal, 2 = with background (i.e. no shine-through)
+    if boxdashtype = 2 :
+        draw start -- start shifted (width,0)
+            withpen pencircle scaled boxgridwidth
+            boxfilloptions ;
+    fi ;
+    draw start -- start shifted (width,0)
+        if boxdashtype > 0 :
+            dashed evenly
+        fi
+        withpen pencircle scaled boxgridwidth
+        boxgridoptions ;
+enddef ;
+
+vardef abck_baseline_grid(expr pxy, pdir, at_baseline) =
+    save width ; width := bbwidth(pxy) ;
+    save height ; height := bbheight(pxy) ;
+    if (par_line_height > 0) and (height > 1) and (width > 1) and (boxgridwidth > 0) :
+        save i, grid, bb ; picture grid ; pair start ; path bb ;
+        grid := image ( % fails with inlinespace
+            if pdir = up :
+                for i = if at_baseline : par_strut_depth else : 0 fi step par_line_height until max(height,par_line_height) :
+                    abck_grid_line(llcorner pxy shifted (0,+i),width) ;
+                endfor ;
+            else :
+                for i = if at_baseline : par_strut_height else : 0 fi step par_line_height until height :
+                    abck_grid_line(ulcorner pxy shifted (0,-i),width) ;
+                endfor ;
+            fi ;
+        ) ;
+        clip grid to pxy ;
+        bb := boundingbox grid ;
+        grid := grid shifted (0,boxgridshift) ;
+        setbounds grid to bb ;
+        grid
+    else :
+        nullpicture
+    fi
+enddef ;
+
+vardef abck_graphic_grid(expr pxy, dx, dy, x, y) =
+    if (bbheight(pxy) > dy) and (bbwidth(pxy) > dx) and (boxgridwidth > 0) :
+        save grid ; picture grid ;
+        grid := image (
+            for i = xpart llcorner pxy step dx until xpart lrcorner pxy :
+                draw (i,ypart llcorner pxy) -- (i,ypart ulcorner pxy) withpen pencircle scaled boxgridwidth ;
+            endfor ;
+            for i = ypart llcorner pxy step dy until ypart ulcorner pxy :
+                draw (xpart llcorner pxy,i) -- (xpart lrcorner pxy,i) withpen pencircle scaled boxgridwidth ;
+            endfor
+        ) shifted (x,y) ;
+        clip grid to pxy ;
+        grid
+    else :
+        nullpicture
+    fi
+enddef ;
+
+def draw_multi_pars =
+    for i=1 upto nofmultipars :
+        abck_draw_path(multipars[i]) ;
+        if boxgridtype = 1 :
+            draw abck_baseline_grid(multipars[i],if multilocs[i]=1: down else: up fi,true) ;
+        elseif boxgridtype = 2 :
+            draw abck_baseline_grid(multipars[i],if multilocs[i]=1: down else: up fi,false) ;
+        elseif boxgridtype = 3 :
+            draw abck_baseline_grid(multipars[i],if multilocs[i]=1: down else: up fi,true) ;
+            draw abck_baseline_grid(multipars[i],if multilocs[i]=1: down else: up fi,true) shifted (0,ExHeight) ;
+        elseif boxgridtype = 4 :
+            draw abck_baseline_grid(multipars[i],if multilocs[i]=1: down else: up fi,true) shifted (0,ExHeight/2) ;
+        elseif boxgridtype = 11 :
+            draw abck_graphic_grid(multipars[i],boxgriddistance,boxgriddistance,boxgriddistance/2,boxgriddistance/2) ;
+        elseif boxgridtype = 12 :
+            draw abck_graphic_grid(multipars[i],boxgriddistance,boxgriddistance,0,0) ;
+        fi ;
+    endfor ;
+enddef ;
+
+def show_multi_pars =
+    for i=1 upto nofmultipars :
+        drawpathwithpoints multipars[i] withcolor .5blue ;
+    endfor ;
+enddef ;
+
+def show_multi_kind =
+    for i=1 upto nofmultipars :
+        fill multipars[i]
+            withcolor
+                if      multikind[i] = "single" : yellow
+                elseif  multikind[i] = "first"  : red
+                elseif  multikind[i] = "middle" : green
+                elseif  multikind[i] = "last"   : blue
+                fi
+            withtransparency (1,.5)
+        ;
+    endfor ;
+enddef ;
+
+def multi_side_draw_options = enddef ;
+
+def draw_multi_side =
+    begingroup ; save p ; picture p ;
+    for i=1 upto nofmultipars :
+        p := image ( fill leftboundary multipars[i]
+            shifted (-boxlineoffset,0)
+            rightenlarged boxlinewidth boxlineoptions ;
+        ) ;
+        setbounds p to multipars[i] ;
+        draw p ;
+    endfor ;
+    endgroup ;
+enddef ;
+
+def draw_multi_side_path text t =
+    begingroup ; save p ; picture p ;
+    for i=1 upto nofmultipars :
+        p := image ( draw leftboundary multipars[i]
+            shifted (-boxlineoffset,0)
+            withpen pensquare scaled boxlinewidth boxlineoptions t ;
+        ) ;
+        setbounds p to multipars[i] ;
+        draw p ;
+    endfor ;
+    endgroup ;
+enddef ;
+
+% some extras
+
+% For the moment we keep these as they can be in use but they will disappear.
+
+pair    lxy[], rxy[], cxy[], llxy[], lrxy[], ulxy[], urxy[] ;
+path    pxy[] ;
+numeric hxy[], wxy[], dxy[], nxy[] ;
+
+def box_found (expr n,x,y,w,h,d) =
+    not ((x=0) and (y=0) and (w=0) and (h=0) and (d=0))
+enddef ;
+
+def initialize_box_pos (expr pos,n,x,y,w,h,d) =
+    pair lxy, rxy, cxy, llxy, lrxy, ulxy, urxy ;
+    path pxy ; numeric hxy, wxy, dxy, nxy;
+    lxy  := (x,y) ;
+    llxy := (x,y-d) ;
+    lrxy := (x+w,y-d) ;
+    urxy := (x+w,y+h) ;
+    ulxy := (x,y+h) ;
+    wxy  := w ;
+    hxy  := h ;
+    dxy  := d ;
+    rxy  := lxy shifted (wxy,0) ;
+    pxy  := llxy--lrxy--urxy--ulxy--cycle ;
+    cxy  := center pxy ;
+    nxy  := n ;
+    freeze_box(pos) ;
+enddef ;
+
+def freeze_box (expr pos) =
+    lxy[pos]  := lxy  ;
+    llxy[pos] := llxy ;
+    lrxy[pos] := lrxy ;
+    urxy[pos] := urxy ;
+    ulxy[pos] := ulxy ;
+    wxy[pos]  := wxy  ;
+    hxy[pos]  := hxy  ;
+    dxy[pos]  := dxy  ;
+    rxy[pos]  := rxy  ;
+    pxy[pos]  := pxy  ;
+    cxy[pos]  := cxy  ;
+    nxy[pos]  := nxy  ;
+enddef ;
+
+def initialize_box (expr n,x,y,w,h,d) =
+    numeric bpos ; bpos := 0 ; initialize_box_pos(bpos,n,x,y,w,h,d) ;
+enddef ;
+
+def anchor_box (expr n,x,y,w,h,d) =
+    currentpicture := currentpicture shifted (-x,-y) ;
+enddef ;
+
+def draw_box = % for old times sake
+    draw pxy        boxlineoptions withpen pencircle scaled boxlinewidth ;
+    draw lxy -- rxy boxlineoptions withpen pencircle scaled boxgridwidth ;
+enddef ;
+
+def draw_free_region(expr width, height, depth, loffset, roffset, toffset, boffset) =
+
+    begingroup ; save b, o, l ; path b, o, l[] ; save d ;
+
+    b := fullsquare
+        xysized(width,height+depth) ;
+    o := b
+        topenlarged    toffset
+        bottomenlarged boffset
+        leftenlarged   loffset
+        rightenlarged  roffset ;
+    d := max(PaperWidth,PaperHeight) ;
+
+    fill o withcolor .5white ;
+    fill b withcolor .7white ;
+
+    interim linecap := butt ;
+
+    l[1] := topboundary    (topboundary    o leftenlarged d rightenlarged  d) ;
+    l[2] := bottomboundary (bottomboundary o leftenlarged d rightenlarged  d) ;
+    l[3] := leftboundary   (leftboundary   o topenlarged  d bottomenlarged d) ;
+    l[4] := rightboundary  (rightboundary  o topenlarged  d bottomenlarged d) ;
+
+    for i=1 upto 4 :
+        draw l[i] withpen pencircle scaled 1bp withcolor white ;
+        draw l[i] withpen pencircle scaled 1bp dashed (evenly scaled 1bp) withcolor black ;
+    endfor ;
+
+    setbounds currentpicture to b ;
+
+    endgroup ;
+
+enddef ;
+