2016-01-12 16:26:00

1 files changed, 241 insertions, 0 deletions

diff --git a/tex/context/base/mkiv/font-aux.lua b/tex/context/base/mkiv/font-aux.lua
new file mode 100644
index 000000000..fc6c90bc1
--- /dev/null
+++ b/tex/context/base/mkiv/font-aux.lua
@@ -0,0 +1,241 @@
+if not modules then modules = { } end modules ['font-aux'] = {
+    version   = 1.001,
+    comment   = "companion to font-ini.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+local tonumber, type = tonumber, type
+----- wrap, yield = coroutine.wrap, coroutine.yield
+
+local fonts, font = fonts, font
+
+local fonts       = fonts
+local handlers    = fonts.handlers
+local otf         = handlers.otf -- brrr
+local afm         = handlers.afm -- brrr
+
+local iterators   = { }
+fonts.iterators   = iterators
+
+local currentfont = font.current
+local identifiers = fonts.hashes.identifiers
+local sortedkeys  = table.sortedkeys
+
+-- for unicode, character   in fonts.iterators.characters  () do print(unicode) end
+-- for unicode, description in fonts.iterators.descriptions() do print(unicode) end
+-- for index,   glyph       in fonts.iterators.glyphs      () do print(index  ) end
+
+local function dummy() end
+
+local function checkeddata(data) -- beware, nullfont is the fallback in identifiers
+    local t = type(data)
+    if t == "table" then
+        return data
+    elseif t ~= "number" then
+        data = currentfont()
+    end
+    return identifiers[data] -- has nullfont as fallback
+end
+
+local function getindices(data)
+    data = checkeddata(data)
+    local indices = { }
+    local characters = data.characters
+    if characters then
+        for unicode, character in next, characters do
+            indices[character.index or unicode] = unicode
+        end
+    end
+    return indices
+end
+
+-- function iterators.characters(data)
+--     data = checkeddata(data)
+--     local characters = data.characters
+--     if characters then
+--         local collected = sortedkeys(characters)
+--         return wrap(function()
+--             for c=1,#collected do
+--                 local cc = collected[c]
+--                 local dc = characters[cc]
+--                 if dc then
+--                     yield(cc,dc)
+--                 end
+--             end
+--         end)
+--     else
+--         return wrap(function() end)
+--     end
+-- end
+
+-- function iterators.descriptions(data)
+--     data = checkeddata(data)
+--     local characters = data.characters
+--     local descriptions = data.descriptions
+--     if characters and descriptions then
+--         local collected = sortedkeys(characters)
+--         return wrap(function()
+--             for c=1,#collected do
+--                 local cc = collected[c]
+--                 local dc = descriptions[cc]
+--                 if dc then
+--                     yield(cc,dc)
+--                 end
+--             end
+--         end)
+--     else
+--         return wrap(function() end)
+--     end
+-- end
+
+-- function iterators.glyphs(data)
+--     data = checkeddata(data)
+--     local descriptions = data.descriptions
+--     if descriptions then
+--         local indices = getindices(data)
+--         local collected = sortedkeys(indices)
+--         return wrap(function()
+--             for c=1,#collected do
+--                 local cc = collected[c]
+--                 local dc = descriptions[indices[cc]]
+--                 if dc then
+--                     yield(cc,dc)
+--                 end
+--             end
+--         end)
+--     else
+--         return wrap(function() end)
+--     end
+-- end
+
+function iterators.characters(data)
+    data = checkeddata(data)
+    local characters = data.characters
+    if characters then
+        local collected = sortedkeys(characters)
+        local n, i = #collected, 0
+        return function()
+            i = i + 1
+            if i <= n then
+                local cc = collected[i]
+                local dc = characters[cc]
+                return cc, dc or { }
+            end
+        end
+    else
+        return dummy
+    end
+end
+
+function iterators.descriptions(data)
+    data = checkeddata(data)
+    local characters = data.characters
+    local descriptions = data.descriptions
+    if characters and descriptions then
+        local collected = sortedkeys(characters)
+        local n, i = #collected, 0
+        return function()
+            i = i + 1
+            if i <= n then
+                local cc = collected[i]
+                local dc = descriptions[cc]
+                return cc, dc or { }
+            end
+        end
+    else
+        return dummy
+    end
+end
+
+function iterators.glyphs(data)
+    data = checkeddata(data)
+    local descriptions = data.descriptions
+    if descriptions then
+        local indices = getindices(data)
+        local collected = sortedkeys(indices)
+        local n, i = #collected, 0
+        return function()
+            i = i + 1
+            if i <= n then
+                local cc = collected[i]
+                local dc = descriptions[indices[cc]]
+                return cc, dc or { }
+            end
+        end
+    else
+        return dummy
+    end
+end
+
+-- for the moment here, it might move to some other file later
+
+function afm.getkern(tfmdata,left,right)
+    local c = tfmdata.characters[left]
+    if c then
+        local kerns = c.kerns
+        if kerns then
+            return kerns[right] -- already scaled
+        end
+    end
+    return 0
+end
+
+local getters = { -- maybe better getters[format][...]
+    kern = {
+        ["type1"]    = afm.getkern,
+        ["opentype"] = otf.getkern,
+    },
+    substitution = {
+        ["opentype"] = otf.getsubstitution,
+    },
+    alternate = {
+        ["opentype"] = otf.getalternate,
+    },
+    multiple = {
+        ["opentype"] = otf.getmultiple,
+    }
+}
+
+fonts.getters = getters
+
+function fonts.getkern(tfmdata,left,right)
+    local format = tfmdata.properties.format
+    local getter = getters.kern[format]
+    if getter then
+        return getter(tfmdata,left,right)
+    else
+        return 0
+    end
+end
+
+function fonts.getsubstitution(tfmdata,k,kind)
+    local format = tfmdata.properties.format
+    local getter = getters.substitution[format]
+    if getter then
+        return getter(tfmdata,k,kind,value)
+    else
+        return 0
+    end
+end
+
+function fonts.getalternate(tfmdata,k,kind,value)
+    local format = tfmdata.properties.format
+    local getter = getters.substitution[format]
+    if getter then
+        return getter(tfmdata,k,kind,value)
+    else
+        return 0
+    end
+end
+
+function fonts.getmultiple(tfmdata,k,kind)
+    local format = tfmdata.properties.format
+    local getter = getters.substitution[format]
+    if getter then
+        return getter(tfmdata,k,kind,value)
+    else
+        return 0
+    end
+end