2018-04-13 15:02:00

1 files changed, 305 insertions, 0 deletions

diff --git a/tex/context/base/mkiv/meta-blb.lua b/tex/context/base/mkiv/meta-blb.lua
new file mode 100644
index 000000000..202c2850b
--- /dev/null
+++ b/tex/context/base/mkiv/meta-blb.lua
@@ -0,0 +1,305 @@
+if not modules then modules = { } end modules ['meta-blb'] = {
+    version   = 1.001,
+    comment   = "companion to mlib-ctx.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files",
+}
+
+-- This could be integrated in other modules but for me it also serves
+-- as an example of usign the plugin mechanism.
+
+local tonumber = tonumber
+
+local setmetatableindex = table.setmetatableindex
+local insert, remove = table.insert, table.remove
+
+local topoints        = number.topoints
+local mpprint         = mp.print
+local mpinteger       = mp.integer
+local mppoints        = mp.points
+local mptriplet       = mp.triplet
+local mptripletpoints = mp.tripletpoints
+
+local texsetbox       = tex.setbox
+local toutf           = nodes.toutf
+local hpack_nodes     = nodes.hpack
+
+local trace           = false
+local report          = logs.reporter("metapost","blobs")
+
+trackers.register("metapost.blobs", function(v) trace = v end)
+
+-- We start with a text that comes from an analyze stage and can end up with
+-- one or more results. For practical reasons we store the blobs in one array
+-- and work with ranges.
+
+local allblobs = { }
+
+local function newcategory(t,k)
+    if trace then
+        report("new category %a",k)
+    end
+    local v = {
+        name  = k,
+        text  = "",
+        blobs = { },
+    }
+    t[k] = v
+    return v
+end
+
+local texblobs = setmetatableindex(newcategory)
+
+local function blob_raw_reset(category)
+    -- we need to keep the allblobs
+    if category then
+        if trace then
+            report("reset category %a",category)
+        end
+        texblobs[category] = nil
+    else
+        if trace then
+            report("reset all")
+        end
+        texblobs = setmetatableindex(newcategory)
+    end
+end
+
+local function blob_raw_dimensions(i)
+    local blob = allblobs[i]
+    if blob then
+        return blob.width, blob.height, blob.depth
+    else
+        return 0, 0, 0
+    end
+end
+
+local function blob_raw_content(i)
+    return allblobs[i]
+end
+
+local function blob_raw_toutf(i)
+    return toutf(allblobs[i])
+end
+
+local function blob_raw_wipe(i)
+    allblobs[i] = false
+end
+
+mp.blob_raw_dimensions = blob_raw_dimensions
+mp.blob_raw_content    = blob_raw_content
+mp.blob_raw_reset      = blob_raw_reset
+mp.blob_raw_wipe       = blob_raw_wipe
+mp.blob_raw_toutf      = blob_raw_toutf
+
+function mp.blob_new(category,text)
+    if trace then
+        report("category %a, text %a",category,text)
+    end
+    texblobs[category].text = text
+end
+
+function mp.blob_add(category,blob)
+    local tb = texblobs[category].blobs
+    local tn = #allblobs + 1
+    blob = hpack_nodes(blob)
+    allblobs[tn] = blob
+    tb[#tb+1] = tn
+    if trace then
+        report("category %a, blob %a set, content %a",category,tn,blob_raw_toutf(tn))
+    end
+end
+
+function mp.blob_width(category,i)
+    local index = texblobs[category].blobs[i]
+    local blob  = allblobs[index]
+    if blob then
+        mppoints(blob.width or 0)
+    else
+        mpinteger(0)
+    end
+end
+
+function mp.blob_size(category,i)
+    mpprint(#texblobs[category].blobs or 0)
+end
+
+function mp.blob_index(category,i)
+    mpprint(texblobs[category].blobs[i] or 0)
+end
+
+function mp.blob_dimensions(category,i)
+    local index = texblobs[category].blobs[i]
+    local blob  = allblobs[index]
+    if blob then
+        mptripletpoints(blob.width,blob.height,blob.depth)
+    else
+        mptriplet(0,0,0)
+    end
+end
+
+local f_f  = string.formatters["%F"]
+local sxsy = metapost.sxsy
+local cm   = metapost.cm
+
+local function injectblob(object,blob)
+    local sx, rx, ry, sy, tx, ty = cm(object)
+    local wd, ht, dp = blob_raw_dimensions(blob)
+    if wd then
+        object.path    = false
+        object.color   = false
+        object.grouped = true
+        object.istext  = true
+        return function()
+            if trace then
+                report("injecting blob %a, width %p, heigth %p, depth %p, text %a",blob,wd,ht,dp,blob_raw_toutf(blob))
+            end
+            context.MPLIBgetblobscaledcm(blob,
+                f_f(sx), f_f(rx), f_f(ry),
+                f_f(sy), f_f(tx), f_f(ty),
+                sxsy(wd,ht,dp))
+        end
+    end
+end
+
+mp.blob_inject = injectblob
+
+local function getblob(box,blob)
+    texsetbox(box,blob_raw_content(blob))
+    blob_raw_wipe(blob)
+end
+
+interfaces.implement {
+    name      = "mpgetblob",
+    actions   = getblob,
+    arguments = { "integer", "integer" },
+}
+
+-- the plug:
+
+local function reset()
+    blob_raw_reset()
+end
+
+local function analyze(object,prescript)
+    -- nothing
+end
+
+local function process(object,prescript,before,after)
+    if prescript.tb_stage == "inject" then
+        local tb_blob = tonumber(prescript.tb_blob)
+        if tb_blob then
+            before[#before+1] = injectblob(object,tb_blob)
+        end
+    end
+end
+
+metapost.installplugin(reset,analyze,process)
+
+-- Here follows an example of usage of the above: a more modern
+-- version of followokens (in meta-imp-txt.mkiv).
+
+local nodecodes       = nodes.nodecodes
+local kerncodes       = nodes.kerncodes
+
+local glue_code       = nodecodes.glue
+local kern_code       = nodecodes.kern
+local c_userkern      = kerncodes.userkern
+local c_fontkern      = kerncodes.fontkern
+local c_italickern    = kerncodes.italickern
+local a_fontkern      = attributes.private("fontkern")
+
+local takebox         = tex.takebox
+local flatten_list    = node.flatten_discretionaries
+local remove_node     = nodes.remove
+local flush_node      = nodes.flush
+
+local addblob         = mp.blob_add
+local newblob         = mp.blob_new
+
+local visible_code = {
+    [nodecodes.glyph] = true,
+    [nodecodes.glue]  = true,
+    [nodecodes.hlist] = true,
+    [nodecodes.vlist] = true,
+    [nodecodes.rule]  = true,
+}
+
+local function initialize(category,box)
+    local wrap = takebox(box)
+    if wrap then
+        local head = wrap.list
+        local tail = nil
+        local temp = nil
+        if head then
+            local n = { }
+            local s = 0
+            head = flatten_list(head)
+            local current = head
+            while current do
+                local id = current.id
+                if visible_code[id] then
+                    head, current, tail = remove_node(head,current)
+                    s = s + 1
+                    n[s] = tail
+                elseif id == kern_code then
+                    local subtype = current.subtype
+                    if subtype == c_fontkern or subtype == italickern then -- or current[a_fontkern]
+                        head, current, temp = remove_node(head,current)
+                        tail.next = temp
+                        temp.prev = tail
+                        tail = temp
+                    else
+                        head, current, temp = remove_node(head,current)
+                        s = s + 1
+                        n[s] = temp
+                    end
+                elseif id == glue_code then
+                    head, current, temp = remove_node(head,current)
+                    s = s + 1
+                    n[s] = temp
+                else
+                    current = current.next
+                end
+            end
+            for i=1,s do
+                n[i] = addblob(category,n[i])
+            end
+            wrap.list = head
+        end
+        flush_node(wrap)
+    end
+end
+
+interfaces.implement {
+    name      = "MPLIBconvertfollowtext",
+    arguments = { "integer","integer" },
+    actions   = initialize,
+}
+
+local function reset()
+    -- nothing
+end
+
+local function analyze(object,prescript)
+    if prescript.ft_stage == "trial" then
+        local ft_category = tonumber(prescript.ft_category)
+        if ft_category then
+            newblob(ft_category,object.postscript) -- only for tracing
+            context.MPLIBfollowtext(ft_category,object.postscript)
+            metapost.getjobdata().multipass = true
+        end
+    end
+end
+
+local function process(object,prescript,before,after)
+    if prescript.ft_stage == "final" then
+        object.path    = false
+        object.color   = false
+        object.grouped = true
+        object.istext  = true
+    end
+end
+
+metapost.installplugin(reset,analyze,process)