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Diffstat (limited to 'tex/context/base/anch-pgr.lua')
| -rw-r--r-- | tex/context/base/anch-pgr.lua | 480 |
1 files changed, 480 insertions, 0 deletions
diff --git a/tex/context/base/anch-pgr.lua b/tex/context/base/anch-pgr.lua new file mode 100644 index 000000000..3d020ca64 --- /dev/null +++ b/tex/context/base/anch-pgr.lua @@ -0,0 +1,480 @@ +if not modules then modules = { } end modules ['anch-pgr'] = { + version = 1.001, + comment = "companion to anch-pgr.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +local format = string.format +local concat, sort = table.concat, table.sort +local splitter = lpeg.splitat(":") +local lpegmatch = lpeg.match + +local jobpositions = job.positions + +local report_graphics = logs.reporter("graphics") + +local function pair(x,y) + return format("(%.5fpt,%.5fpt)",x/65536,y/65536) +end + +local function path(t) + return concat(t,"--") .. "--cycle" +end + +local function regionarea(r) + local rx, ry = r.x, r.y + local rw = rx + r.w + local rh = ry + r.h + local rd = ry - r.d + return { + pair(rx, rh - ry), + pair(rw, rh - ry), + pair(rw, rd - ry), + pair(rx, rd - ry), + } +end + +local function add(t,x,y) + local last = t[#t] + if not last or last[1] ~= x or last[2] ~= y then + t[#t+1] = { x, y } + end +end + +local function clip(t,ytop,ybot) + local first, last = 1, #t + for i=first,last do + local y = t[i][2] + if ytop < y then + first = i + end + if ybot > y then + last = i + break + end + end + local lp = { } + lp[#lp+1] = { t[first][1], ytop } + for i=first+1,last-1 do + lp[#lp+1] = { t[i][1], t[i][2] } + end + lp[#lp+1] = { t[last][1], ybot } + return lp +end + +local function shapes(r,rx,ry,rw,rh,rd,lytop,lybot,rytop,rybot) + -- we assume that we only hang per page and not cross pages + -- which makes sense as hanging is only uses in special cases + -- + -- we can remove data as soon as a page is done so we could + -- remember per page and discard areas after each shipout + local paragraphs = r.paragraphs + local left = { { rx, rh } } + local right = { { rw, rh } } + if paragraphs then + for i=1,#paragraphs do + local p = paragraphs[i] + local ha = p.ha + if ha and ha ~= 0 then + local py = p.y + local ph = p.h + local pd = p.d + local hi = p.hi + local hang = ha * (ph + pd) + local py_ph = py + ph + -- ha < 0 hi < 0 : right top + -- ha < 0 hi > 0 : left top + if ha < 0 then + if hi < 0 then -- right + add(right,rw , py_ph) + add(right,rw + hi, py_ph) + add(right,rw + hi, py_ph + hang) + add(right,rw , py_ph + hang) + else + -- left + add(left,rx, py_ph) + add(left,rx + hi, py_ph) + add(left,rx + hi, py_ph + hang) + add(left,rx, py_ph + hang) + end + end + end + end + end + -- we can have a simple variant when no paragraphs + add(left,rx,rd) + add(right,rw,rd) + return clip(left,lytop,lybot), clip(right,rytop,rybot) +end + +local function singlepart(b,e,r,left,right) + local bx, by = b.x, b.y + local ex, ey = e.x, e.y + local rx, ry = r.x, r.y + local rw = rx + r.w + local rh = ry + r.h + local rd = ry - r.d + if left then + rx = rx + left + rw = rw - right + end + local bh = by + b.h + local bd = by - b.d + local eh = ey + e.h + local ed = ey - e.d + local area = { } + local leftshapes, rightshapes = shapes(r,rx,ry,rw,rh,rd,bd,ed,bh,eh) + add(area,bx,bh-ry) + for i=1,#rightshapes do + local ri = rightshapes[i] + add(area,ri[1],ri[2]-ry) + end + add(area,ex,eh-ry) + add(area,ex,ed-ry) + for i=#leftshapes,1,-1 do + local li = leftshapes[i] + add(area,li[1],li[2]-ry) + end + add(area,bx,bd-ry) + for i=1,#area do + local a = area[i] + area[i] = pair(a[1],a[2]) + end + return { -- no collapsing yet + location = "single", + region = r, + area = area, + } +end + +local function firstpart(b,r,left,right) + local bx, by = b.x, b.y + local rx, ry = r.x, r.y + local rw = rx + r.w + local rh = ry + r.h + local rd = ry - r.d + if left then + rx = rx + left + rw = rw - right + end + local bh = by + b.h + local bd = by - b.d + local area = { } + local leftshapes, rightshapes = shapes(r,rx,ry,rw,rh,rd,bd,rd,bh,rd) + add(area,bx,bh-ry) + for i=1,#rightshapes do + local ri = rightshapes[i] + add(area,ri[1],ri[2]-ry) + end + for i=#leftshapes,1,-1 do + local li = leftshapes[i] + add(area,li[1],li[2]-ry) + end + add(area,bx,bd-ry) + for i=1,#area do + local a = area[i] + area[i] = pair(a[1],a[2]) + end + return { + location = "first", + region = r, + area = area, + } +end + +local function middlepart(r,left,right) + local rx, ry = r.x, r.y + local rw = rx + r.w + local rh = ry + r.h + local rd = ry - r.d + if left then + rx = rx + left + rw = rw - right + end + local area = { } + local leftshapes, rightshapes = shapes(r,rx,ry,rw,rh,rd,rh,rd,rh,rd) + for i=#leftshapes,1,-1 do + local li = leftshapes[i] + add(area,li[1],li[2]-ry) + end + for i=1,#rightshapes do + local ri = rightshapes[i] + add(area,ri[1],ri[2]-ry) + end + for i=1,#area do + local a = area[i] + area[i] = pair(a[1],a[2]) + end + return { + location = "middle", + region = r, + area = area, + } +end + +local function lastpart(e,r,left,right) + local ex, ey = e.x, e.y + local rx, ry = r.x, r.y + local rw = rx + r.w + local rh = ry + r.h + local rd = ry - r.d + if left then + rx = rx + left + rw = rw - right + end + local eh = ey + e.h + local ed = ey - e.d + local area = { } + -- two cases: till end and halfway e line + local leftshapes, rightshapes = shapes(r,rx,ry,rw,rh,rd,rh,ed,rh,eh) + for i=1,#rightshapes do + local ri = rightshapes[i] + add(area,ri[1],ri[2]-ry) + end + add(area,ex,eh-ry) + add(area,ex,ed-ry) + for i=#leftshapes,1,-1 do + local li = leftshapes[i] + add(area,li[1],li[2]-ry) + end + for i=1,#area do + local a = area[i] + area[i] = pair(a[1],a[2]) + end + return { + location = "last", + region = r, + area = area, + } +end + +graphics = graphics or { } +local backgrounds = { } + +graphics.backgrounds = backgrounds + +local function calculate(tag) + local collected = jobpositions.collected + local b = collected[format("b:%s",tag)] + local e = collected[format("e:%s",tag)] + if not b or not e then + report_graphics("invalid tag '%s'",tag) + return { } + end + local br = b.r + local er = e.r + if not br or not er then + report_graphics("invalid region for '%s'",tag) + return { } + end + local btag, bindex = lpegmatch(splitter,br) + local etag, eindex = lpegmatch(splitter,er) + if not bindex or not eindex or btag ~= etag then + report_graphics("invalid indices for '%s'",tag) + return { } + end + local bindex = tonumber(bindex) + local eindex = tonumber(eindex) + -- Here we compensate for columns (in tables): a table can have a set of column + -- entries and these are shared. We compensate left/right based on the columns + -- x and w but need to take the region into acount where the specification was + -- flushed and not the begin pos's region, because otherwise we get the wrong + -- compensation for assymetrical doublesided layouts. + local left = 0 + local right = 0 + local rc = b.c + if rc then + rc = collected[rc] + if rc then + local tb = collected[rc.r] + if tb then + left = -(tb.x - rc.x) + right = (tb.w - rc.w - left) -- tb.x - rc.x + end + end + end + -- Obeying intermediate changes of left/rightskip makes no sense as it will + -- look bad, so we only look at the begin situation. + -- + local bn = b.n + if bn then + local bp = collected[format("p:%s",bn)] + if bp then + left = left + bp.ls + right = right + bp.rs + end + end + -- + if bindex == eindex then + return { + [b.p] = { singlepart(b,e,collected[br],left,right) } + } + else + local pars = { + [b.p] = { firstpart(b,collected[br],left,right) } + } + for i=bindex+1,eindex-1 do + br = format("%s:%s",btag,i) + local r = collected[br] + if not r then + report_graphics("invalid middle for '%s'",br) + else + local p = r.p + local pp = pars[p] + if pp then + pp[#pp+1] = middlepart(r,left,right) + else + pars[p] = { middlepart(r,left,right) } + end + end + end + local p = e.p + local pp = pars[p] + if pp then + pp[#pp+1] = lastpart(e,collected[er],left,right) + else + pars[p] = { lastpart(e,collected[er],left,right) } + end + return pars + end +end + +local pending = { } -- needs gc + +local function register(data,n,anchor) + local pa = pending[anchor] + if not pa then + pa = { } + pending[anchor] = pa + end + for page, pagedata in next, data do + local pap = pa[page] + if pap then + pap[#pap+1] = n + else + pa[page] = { n } + end + end +end + +function graphics.backgrounds.registered(anchor,page) + local pa = pending[anchor] + if pa then + concat(pa,",") + else + return "" + end +end + +local pbg = { } -- will move to pending + +function graphics.backgrounds.calculate(n) + if not pbg[n] then + pbg[n] = calculate("pbg",n) or { } + end +end + +local multilocs = { + single = 1, -- maybe 0 + first = 1, + middle = 2, + last = 3, +} + +local template_a = [[ +path multiregs[], multipars[], multibox ; +string multikind[] ; +numeric multilocs[], nofmultipars ; +nofmultipars := %s ; +multibox := unitsquare xyscaled %s ; +]] + +local template_b = [[ +multilocs[%s] := %s ; +multikind[%s] := "%s" ; +multipars[%s] := (%s) shifted - %s ; +]] + +local template_c = [[ +multiregs[%s] := (%s) shifted - %s ; +]] + +local template_d = [[ +setbounds currentpicture to multibox ; +]] + +function graphics.backgrounds.fetch(n,page,anchor) + local data = pbg[n] + if not data then + data = calculate(n) + pbg[n] = data -- can be replaced by register + register(data,n,anchor) + end + if data then + local pagedata = data[page] + if pagedata then + local nofmultipars = #pagedata +-- report_graphics("fetching '%s' at page %s using anchor '%s' containing %s multipars",n,page,anchor,nofmultipars) + local a = jobpositions.collected[anchor] + if not a then + report_graphics("missing anchor '%s'",anchor) + else + local trace = false + local x, y, w, h, d = a.x, a.y, a.w, a.h, a.d + local result = { format(template_a,nofmultipars,pair(w,h+d)) } + for i=1,nofmultipars do + local region = pagedata[i] + result[#result+1] = format(template_b, + i, multilocs[region.location], + i, region.location, + i, path(region.area), pair(x,y-region.region.y)) + if trace then + result[#result+1] = format(template_c, + i, path(regionarea(region.region)), offset) + end + end + data[page] = nil + result[#result+1] = template_d + result = concat(result,"\n") + return result + end + end + end + return format(template_a,0,"origin") +end + +function commands.fetchmultipar(n,page,anchor) + context(graphics.backgrounds.fetch(n,page,anchor)) +end + +local doifelse = commands.doifelse + +function commands.doifelsemultipar(n,page) + local data = pbg[n] + if not data then + data = calculate(n) + pbg[n] = data + end + if page then + doifelse(data and data[page] and true) + else + doifelse(data and next(data) and true) + end +end + +function commands.doifelserangeonpage(first,last,page) + local collected = jobpositions.collected + local f = collected[first] + if not f then + doifelse(false) + return + end + local l = collected[last] + if not l then + doifelse(false) + return + end + doifelse(page >= f.p and page <= l.p) +end |