1 files changed, 157 insertions, 0 deletions
diff --git a/tex/context/base/spac-chr.lua b/tex/context/base/spac-chr.lua
new file mode 100644
index 000000000..601b90645
--- /dev/null
+++ b/tex/context/base/spac-chr.lua
@@ -0,0 +1,157 @@
+if not modules then modules = { } end modules ['spac-chr'] = {
+    version   = 1.001,
+    comment   = "companion to spac-chr.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+local byte = string.byte
+
+----- trace_characters = false  trackers.register("typesetters.characters", function(v) trace_characters = v end)
+-----
+----- report_characters = logs.reporter("typesetting","characters")
+
+local nodes, node = nodes, node
+
+local set_attribute      = node.set_attribute
+local insert_node_after  = node.insert_after
+local remove_node        = nodes.remove -- ! nodes
+
+local nodepool           = nodes.pool
+local tasks              = nodes.tasks
+
+local new_penalty        = nodepool.penalty
+local new_glue           = nodepool.glue
+
+local nodecodes          = nodes.nodecodes
+local glyph_code         = nodecodes.glyph
+
+local typesetters        = typesetters
+
+local characters         = { }
+typesetters.characters   = characters
+
+local fontparameters     = fonts.hashes.parameters
+local fontcharacters     = fonts.hashes.characters
+
+local a_character        = attributes.private("characters")
+
+local c_zero   = byte('0')
+local c_period = byte('.')
+
+local function inject_quad_space(unicode,head,current,fraction)
+    local attr = current.attr
+    if fraction ~= 0 then
+        fraction = fraction * fontparameters[current.font].quad
+    end
+    head, current = insert_node_after(head,current,new_glue(fraction))
+    current.attr = attr
+    set_attribute(current,a_character,unicode)
+    return head, current
+end
+
+local function inject_char_space(unicode,head,current,parent)
+    local attr = current.attr
+    local char = fontcharacters[current.font][parent]
+    head, current = insert_node_after(head,current,new_glue(char and char.width or fontparameters[current.font].space))
+    current.attr = attr
+    set_attribute(current,a_character,unicode)
+    return head, current
+end
+
+local function inject_nobreak_space(unicode,head,current,space,spacestretch,spaceshrink)
+    local attr = current.attr
+    head, current = insert_node_after(head,current,new_glue(space,spacestretch,spaceshrink))
+    current.attr = attr
+    set_attribute(current,a_character,unicode)
+    head, current = insert_node_after(head,current,new_penalty(10000))
+    return head, current
+end
+
+local methods = {
+
+    [0x00A0] = function(head,current) -- nobreakspace
+        local para = fontparameters[current.font]
+        return inject_nobreak_space(0x00A0,head,current,para.space,para.spacestretch,para.spaceshrink)
+    end,
+
+    [0x2000] = function(head,current) -- enquad
+        return inject_quad_space(0x2000,head,current,1/2)
+    end,
+
+    [0x2001] = function(head,current) -- emquad
+        return inject_quad_space(0x2001,head,current,1)
+    end,
+
+    [0x2002] = function(head,current) -- enspace
+        return inject_quad_space(0x2002,head,current,1/2)
+    end,
+
+    [0x2003] = function(head,current) -- emspace
+        return inject_quad_space(0x2003,head,current,1)
+    end,
+
+    [0x2004] = function(head,current) -- threeperemspace
+        return inject_quad_space(0x2004,head,current,1/3)
+    end,
+
+    [0x2005] = function(head,current) -- fourperemspace
+        return inject_quad_space(0x2005,head,current,1/4)
+    end,
+
+    [0x2006] = function(head,current) -- sixperemspace
+        return inject_quad_space(0x2006,head,current,1/6)
+    end,
+
+    [0x2007] = function(head,current) -- figurespace
+        return inject_char_space(0x2007,head,current,c_zero)
+    end,
+
+    [0x2008] = function(head,current) -- punctuationspace
+        return inject_char_space(0x2008,head,current,c_period)
+    end,
+
+    [0x2009] = function(head,current) -- breakablethinspace
+        return inject_quad_space(0x2009,head,current,1/8) -- same as next
+    end,
+
+    [0x200A] = function(head,current) -- hairspace
+        return inject_quad_space(0x200A,head,current,1/8) -- same as previous (todo)
+    end,
+
+    [0x200B] = function(head,current) -- zerowidthspace
+        return inject_quad_space(0x200B,head,current,0)
+    end,
+
+    [0x202F] = function(head,current) -- narrownobreakspace
+        return inject_nobreak_space(0x202F,head,current,fontparameters[current.font].space/8)
+    end,
+
+    [0x205F] = function(head,current) -- math thinspace
+        return inject_nobreak_space(0x205F,head,current,fontparameters[current.font].space/8)
+    end,
+
+ -- [0xFEFF] = function(head,current) -- zerowidthnobreakspace
+ --     return head, current
+ -- end,
+
+}
+
+function characters.handler(head)
+    local current = head
+    local done = false
+    while current do
+        local next = current.next
+        if current.id == glyph_code then
+            local method = methods[current.char]
+            if method then
+                head = method(head,current)
+                head = remove_node(head,current,true)
+                done = true
+            end
+        end
+        current = next
+    end
+    return head, done
+end