2016-01-12 16:26:00

1 files changed, 295 insertions, 0 deletions

diff --git a/tex/context/base/mkiv/lpdf-grp.lua b/tex/context/base/mkiv/lpdf-grp.lua
new file mode 100644
index 000000000..0eac52dfb
--- /dev/null
+++ b/tex/context/base/mkiv/lpdf-grp.lua
@@ -0,0 +1,295 @@
+if not modules then modules = { } end modules ['lpdf-grp'] = {
+    version   = 1.001,
+    comment   = "companion to lpdf-ini.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+local type = type
+local formatters, gsub = string.formatters, string.gsub
+local concat = table.concat
+local round = math.round
+
+local backends, lpdf = backends, lpdf
+
+local nodeinjections = backends.pdf.nodeinjections
+
+local colors         = attributes.colors
+local basepoints     = number.dimenfactors["bp"]
+local inches         = number.dimenfactors["in"]
+
+local nodeinjections = backends.pdf.nodeinjections
+local codeinjections = backends.pdf.codeinjections
+local registrations  = backends.pdf.registrations
+
+local pdfdictionary  = lpdf.dictionary
+local pdfarray       = lpdf.array
+local pdfconstant    = lpdf.constant
+local pdfboolean     = lpdf.boolean
+local pdfreference   = lpdf.reference
+local pdfflushobject = lpdf.flushobject
+
+-- can also be done indirectly:
+--
+-- 12 : << /AntiAlias false /ColorSpace  8 0 R /Coords [ 0.0 0.0 1.0 0.0 ] /Domain [ 0.0 1.0 ] /Extend [ true true ] /Function 22 0 R /ShadingType 2 >>
+-- 22 : << /Bounds [ ] /Domain [ 0.0 1.0 ] /Encode [ 0.0 1.0 ] /FunctionType 3 /Functions [ 31 0 R ] >>
+-- 31 : << /C0 [ 1.0 0.0 ] /C1 [ 0.0 1.0 ] /Domain [ 0.0 1.0 ] /FunctionType 2 /N 1.0 >>
+
+local function shade(stype,name,domain,color_a,color_b,n,colorspace,coordinates,separation,steps)
+    if steps then
+        color_a = color_a[1]
+        color_b = color_b[1]
+    end
+    local f = pdfdictionary {
+        FunctionType = 2,
+        Domain       = pdfarray(domain), -- domain is actually a string
+        C0           = pdfarray(color_a),
+        C1           = pdfarray(color_b),
+        N            = tonumber(n),
+    }
+    separation = separation and registrations.getspotcolorreference(separation)
+    local s = pdfdictionary {
+        ShadingType = stype,
+        ColorSpace  = separation and pdfreference(separation) or pdfconstant(colorspace),
+        Function    = pdfreference(pdfflushobject(f)),
+        Coords      = pdfarray(coordinates),
+        Extend      = pdfarray { true, true },
+        AntiAlias   = pdfboolean(true),
+    }
+    lpdf.adddocumentshade(name,pdfreference(pdfflushobject(s)))
+end
+
+local function shade(stype,name,domain,color_a,color_b,n,colorspace,coordinates,separation,steps,fractions)
+    local func = nil
+    if steps then
+        local list   = pdfarray()
+        local bounds = pdfarray()
+        local encode = pdfarray()
+        for i=1,steps do
+            bounds[i]     = fractions[i] or 1
+            encode[2*i-1] = 0
+            encode[2*i]   = 1
+            list  [i]     = pdfdictionary {
+                FunctionType = 2,
+                Domain       = pdfarray(domain), -- domain is actually a string
+                C0           = pdfarray(color_a[i]),
+                C1           = pdfarray(color_b[i]),
+                N            = tonumber(n),
+            }
+        end
+        func = pdfdictionary {
+            FunctionType = 3,
+            Bounds       = bounds,
+            Encode       = encode,
+            Functions    = list,
+            Domain       = pdfarray(domain), -- domain is actually a string
+        }
+    else
+        func = pdfdictionary {
+            FunctionType = 2,
+            Domain       = pdfarray(domain), -- domain is actually a string
+            C0           = pdfarray(color_a),
+            C1           = pdfarray(color_b),
+            N            = tonumber(n),
+        }
+    end
+    separation = separation and registrations.getspotcolorreference(separation)
+    local s = pdfdictionary {
+        ShadingType = stype,
+        ColorSpace  = separation and pdfreference(separation) or pdfconstant(colorspace),
+        Function    = pdfreference(pdfflushobject(func)),
+        Coords      = pdfarray(coordinates),
+        Extend      = pdfarray { true, true },
+        AntiAlias   = pdfboolean(true),
+    }
+    lpdf.adddocumentshade(name,pdfreference(pdfflushobject(s)))
+end
+
+function lpdf.circularshade(name,domain,color_a,color_b,n,colorspace,coordinates,separation,steps,fractions)
+    shade(3,name,domain,color_a,color_b,n,colorspace,coordinates,separation,steps,fractions)
+end
+
+function lpdf.linearshade(name,domain,color_a,color_b,n,colorspace,coordinates,separation,steps,fractions)
+    shade(2,name,domain,color_a,color_b,n,colorspace,coordinates,separation,steps,fractions)
+end
+
+-- inline bitmaps but xform'd
+--
+-- we could derive the colorspace if we strip the data
+-- and divide by x*y
+
+local template = "q BI %s ID %s > EI Q"
+local factor   = 72/300
+
+function nodeinjections.injectbitmap(t)
+    -- encoding is ascii hex, no checking here
+    local xresolution, yresolution = t.xresolution or 0, t.yresolution or 0
+    if xresolution == 0 or yresolution == 0 then
+        return -- fatal error
+    end
+    local colorspace = t.colorspace
+    if colorspace ~= "rgb" and colorspace ~= "cmyk" and colorspace ~= "gray" then
+        -- not that efficient but ok
+        local d = gsub(t.data,"[^0-9a-f]","")
+        local b = math.round(#d / (xresolution * yresolution))
+        if b == 2 then
+            colorspace = "gray"
+        elseif b == 6 then
+            colorspace = "rgb"
+        elseif b == 8 then
+            colorspace = "cmyk"
+        end
+    end
+    colorspace = lpdf.colorspaceconstants[colorspace]
+    if not colorspace then
+        return -- fatal error
+    end
+    local d = pdfdictionary {
+        W   = xresolution,
+        H   = yresolution,
+        CS  = colorspace,
+        BPC = 8,
+        F   = pdfconstant("AHx"),
+     -- CS  = nil,
+     -- BPC = 1,
+     -- IM = true,
+    }
+    -- for some reasons it only works well if we take a 1bp boundingbox
+    local urx, ury = 1/basepoints, 1/basepoints
+ -- urx = (xresolution/300)/basepoints
+ -- ury = (yresolution/300)/basepoints
+    local width, height = t.width or 0, t.height or 0
+    if width == 0 and height == 0 then
+        width  = factor * xresolution / basepoints
+        height = factor * yresolution / basepoints
+    elseif width == 0 then
+        width  = height * xresolution / yresolution
+    elseif height == 0 then
+        height = width  * yresolution / xresolution
+    end
+    local image = img.new {
+        stream = formatters[template](d(),t.data),
+        width  = width,
+        height = height,
+        bbox   = { 0, 0, urx, ury },
+    }
+    return img.node(image)
+end
+
+-- general graphic helpers
+
+function codeinjections.setfigurealternative(data,figure)
+    local request = data.request
+    local display = request.display
+    if display and display ~= ""  then
+        local nested = figures.push {
+            name   = display,
+            page   = request.page,
+            size   = request.size,
+            prefix = request.prefix,
+            cache  = request.cache,
+            width  = request.width,
+            height = request.height,
+        }
+        figures.identify()
+        local displayfigure = figures.check()
+        if displayfigure then
+        --  figure.aform = true
+            img.immediatewrite(figure)
+            local a = pdfarray {
+                pdfdictionary {
+                    Image              = pdfreference(figure.objnum),
+                    DefaultForPrinting = true,
+                }
+            }
+            local d = pdfdictionary {
+                Alternates = pdfreference(pdfflushobject(a)),
+            }
+            displayfigure.attr = d()
+            figures.pop()
+            return displayfigure, nested
+        else
+            figures.pop()
+        end
+    end
+end
+
+function codeinjections.getpreviewfigure(request)
+    local figure = figures.initialize(request)
+    if not figure then
+        return
+    end
+    figure = figures.identify(figure)
+    if not (figure and figure.status and figure.status.fullname) then
+        return
+    end
+    figure = figures.check(figure)
+    if not (figure and figure.status and figure.status.fullname) then
+        return
+    end
+    local image = figure.status.private
+    if image then
+        img.immediatewrite(image)
+    end
+    return figure
+end
+
+function codeinjections.setfiguremask(data,figure) -- mark
+    local request = data.request
+    local mask = request.mask
+    if mask and mask ~= ""  then
+        figures.push {
+            name   = mask,
+            page   = request.page,
+            size   = request.size,
+            prefix = request.prefix,
+            cache  = request.cache,
+            width  = request.width,
+            height = request.height,
+        }
+        figures.identify()
+        local maskfigure = figures.check()
+        if maskfigure then
+            local image = maskfigure.status.private
+            if image then
+                img.immediatewrite(image)
+                local d = pdfdictionary {
+                    Interpolate  = false,
+                    SMask        = pdfreference(image.objnum),
+                }
+                figure.attr = d()
+            end
+        end
+        figures.pop()
+    end
+end
+
+-- temp hack
+
+local factor = number.dimenfactors.bp
+
+function img.package(image) -- see lpdf-u3d **
+    local boundingbox = image.bbox
+    local imagetag    = "Im" .. image.index
+    local resources   = pdfdictionary {
+        ProcSet = pdfarray {
+            pdfconstant("PDF"),
+            pdfconstant("ImageC")
+        },
+        Resources = pdfdictionary {
+            XObject = pdfdictionary {
+                [imagetag] = pdfreference(image.objnum)
+            }
+        }
+    }
+    local width = boundingbox[3]
+    local height = boundingbox[4]
+    local xform = img.scan {
+        attr   = resources(),
+        stream = formatters["%F 0 0 %F 0 0 cm /%s Do"](width,height,imagetag),
+        bbox   = { 0, 0, width/factor, height/factor },
+    }
+    img.immediatewrite(xform)
+    return xform
+end