diff options
Diffstat (limited to 'Master/texmf-dist/tex/luatex/minim/minim-pdfresources.lua')
| -rw-r--r-- | Master/texmf-dist/tex/luatex/minim/minim-pdfresources.lua | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/Master/texmf-dist/tex/luatex/minim/minim-pdfresources.lua b/Master/texmf-dist/tex/luatex/minim/minim-pdfresources.lua new file mode 100644 index 00000000000..bc09aeaf401 --- /dev/null +++ b/Master/texmf-dist/tex/luatex/minim/minim-pdfresources.lua @@ -0,0 +1,154 @@ + +local M = { } + +local alloc = require 'minim-alloc' +local cb = require 'minim-callbacks' + +-- the standard table design +local function init_resources() + return { + ExtGState = { }, + ColorSpace = { }, + Pattern = { }, + Shading = { }, + } +end + +-- the module will use optex’s functions if present +M.self_destruct = pdf.add_page_resource or false + +-- resource_data is a table that can contain any data. only the following keys +-- are used by this module: +-- +-- _entry_ internal value; do not use +-- value value in the resource dictionary +-- write() called for writing the resource to the pdf; returns value +-- +-- of the last two, only one needs be present; if the value is missing it will +-- be set at first use to the result of write(). +-- +local resource_data = init_resources() -- name ↦ { [write = ... | value = ...], ... } +-- +function M.add_resource(kind, name, resource) + resource_data[kind][name] = resource +end +function M.get_resource(kind, name) + return resource_data[kind][name] +end +function M.use_resource(kind, name) + local res = resource_data[kind][name] + if not res then + return alloc.err('Unknown %s resource: %s', kind, name) + end + res.value = res.value or res:write() + if not res._entry_ then -- first-use + res._entry_ = string.format('%s %s', alloc.pdf_name(name), res.value) + if M.self_destruct then + M.self_destruct(kind, name, res.value) + end + end + return res._entry_ +end + +-- global resources are mainly for pgf compatibility: contains adds entries to +-- the resource dictionaries that will be added for every page. +-- +local global_resources = init_resources() -- name ↦ '/Key <value>' +-- +function M.add_global_resource(kind, name, value) + local r = global_resources[kind] + if M.self_destruct then + M.self_destruct(kind, name, value) + elseif name == nil then -- used for pgf compatibility + if value ~= '' then + r[''] = r[''] and string.format('%s %s', global_resources[kind][''], value) or value + end + else + r[name] = string.format('%s %s', alloc.pdf_name(name), value) + end +end + +-- we can now provide optex’s interface +if not M.self_destruct then + pdf.add_page_resource = M.add_global_resource +end + +-- for nonglobal resources, every use must be markes with a late_lua node. from +-- those, the M.use_resouce() function will be called automatically. +-- +local page_resources = init_resources() -- name ↦ '/Key <value>' +-- +function _with_pdf_resource_(kind, name) -- global, for use in latelua + page_resources[kind][name] = M.use_resource(kind, name) +end +function M.use_resource_node(kind, name) + local n = node.new('whatsit', 'late_lua') + n.data = string.format('_with_pdf_resource_("%s", "%s")', kind, name) + return n +end + +-- construction and caching of resource dictionaries. +-- +local previous_dicts = init_resources() -- pdf dict ↦ objnum +-- +local function make_resource_entry(kind) + local arr = { } + for _, entry in pairs(page_resources[kind]) do table.insert(arr, entry) end + for _, entry in pairs(global_resources[kind]) do table.insert(arr, entry) end + if #arr == 0 then return false end + table.sort(arr) + arr[0] = '<<'; table.insert(arr, '>>') + local dict = table.concat(arr, ' ', 0) + local objnum = previous_dicts[kind][dict] + if not objnum then + objnum = pdf.obj(dict) + pdf.refobj(objnum) + previous_dicts[kind][dict] = objnum + end + return string.format('/%s %d 0 R', kind, objnum) +end + +local removal_regex = { + ExtGState = ' */ExtGState *%d+ +0 *R', + ColorSpace = ' */ColorSpace *%d+ +0 *R', + Pattern = ' */Pattern *%d+ +0 *R', + Shading = ' */Shading *%d+ +0 *R' } + +local function update_page_resources(shippingout) + if M.self_destruct then return end + local resources = shippingout and pdf.getpageresources() or pdf.getxformresources() or '' + for kind, used in pairs(page_resources) do + resources = string.gsub(resources, removal_regex[kind], '') + local entry = make_resource_entry(kind) + if entry then + resources = resources == '' and entry or string.format('%s %s', resources, entry) + end + end + -- update page resources + if shippingout then + pdf.setpageresources(resources) + else + pdf.setxformresources(resources) + end + page_resources = init_resources() +end + +cb.register('finish_pdfpage', update_page_resources) + +-- for pgf compatibility, reroute the pgf resource registration functions to +-- our global resource pool. +-- +alloc.luadef('minim:pgf:fix:luaside', function() + alloc.luadef('pgf@sys@addpdfresource@extgs@plain', function() + M.add_global_resource('ExtGState', nil, token.scan_string()) + end) + alloc.luadef('pgf@sys@addpdfresource@patterns@plain', function() + M.add_global_resource('Pattern', nil, token.scan_string()) + end) + alloc.luadef('pgf@sys@addpdfresource@colorspaces@plain', function() + M.add_global_resource('ColorSpace', nil, token.scan_string()) + end) +end) + +return M + |