stable 2010-05-24 13:10

1 files changed, 167 insertions, 0 deletions

diff --git a/tex/context/base/typo-spa.lua b/tex/context/base/typo-spa.lua
new file mode 100644
index 000000000..48c7263c7
--- /dev/null
+++ b/tex/context/base/typo-spa.lua
@@ -0,0 +1,167 @@
+if not modules then modules = { } end modules ['typo-spa'] = {
+    version   = 1.001,
+    comment   = "companion to typo-spa.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+-- get rid of tex.scale here
+
+local utf = unicode.utf8
+
+local next, type = next, type
+local utfchar = utf.char
+
+local trace_hspacing     = false  trackers.register("nodes.hspacing",      function(v) trace_hspacing      = v end)
+
+local has_attribute      = node.has_attribute
+local unset_attribute    = node.unset_attribute
+local insert_node_before = node.insert_before
+local insert_node_after  = node.insert_after
+local remove_node        = nodes.remove
+local make_penalty_node  = nodes.penalty
+local make_glue_node     = nodes.glue
+local glyph              = node.id("glyph")
+
+local fontdata           = fonts.identifiers
+local quaddata           = fonts.quads
+
+spacings           = spacings         or { }
+spacings.mapping   = spacings.mapping or { }
+spacings.attribute = attributes.private("spacing")
+
+storage.register("spacings/mapping", spacings.mapping, "spacings.mapping")
+
+function spacings.setspacing(id,char,left,right,alternative)
+    local mapping = spacings.mapping[id]
+    if not mapping then
+        mapping = { }
+        spacings.mapping[id] = mapping
+    end
+    local map = mapping[char]
+    if not map then
+        map = { }
+        mapping[char] = map
+    end
+    map.left, map.right, map.alternative = left, right, alternative
+end
+
+function spacings.process(namespace,attribute,head)
+    local done, mapping = false, spacings.mapping
+    local start = head
+    -- head is always begin of par (whatsit), so we have at least two prev nodes
+    -- penalty followed by glue
+    while start do
+        if start.id == glyph then
+            local attr = has_attribute(start,attribute)
+            if attr and attr > 0 then
+                local map = mapping[attr]
+                if map then
+                    map = map[start.char]
+                    unset_attribute(start,attribute) -- needed?
+                    if map then
+                        local left, right, alternative = map.left, map.right, map.alternative
+                        local quad = quaddata[start.font]
+                        local prev = start.prev
+                        if left and left ~= 0 and prev then
+                            local ok = false
+                            if alternative == 1 then
+                                local somespace = nodes.somespace(prev,true)
+                                if somespace then
+                                    local prevprev = prev.prev
+                                    local somepenalty = nodes.somepenalty(prevprev,10000)
+                                    if somepenalty then
+                                        if trace_hspacing then
+                                            logs.report("spacing","removing penalty and space before %s", utfchar(start.char))
+                                        end
+                                        head, _ = remove_node(head,prev,true)
+                                        head, _ = remove_node(head,prevprev,true)
+                                    else
+                                        local somespace = nodes.somespace(prev,true)
+                                        if somespace then
+                                            if trace_hspacing then
+                                                logs.report("spacing","removing space before %s", utfchar(start.char))
+                                            end
+                                            head, _ = remove_node(head,prev,true)
+                                        end
+                                    end
+                                end
+                                ok = true
+                            else
+                                ok = not (nodes.somespace(prev,true) and nodes.somepenalty(prev.prev,true)) or nodes.somespace(prev,true)
+                            end
+                            if ok then
+                                if trace_hspacing then
+                                    logs.report("spacing","inserting penalty and space before %s", utfchar(start.char))
+                                end
+                                insert_node_before(head,start,make_penalty_node(10000))
+                                insert_node_before(head,start,make_glue_node(tex.scale(quad,left)))
+                                done = true
+                            end
+                        end
+                        local next = start.next
+                        if right and right ~= 0 and next then
+                            local ok = false
+                            if alternative == 1 then
+                                local somepenalty = nodes.somepenalty(next,10000)
+                                if somepenalty then
+                                    local nextnext = next.next
+                                    local somespace = nodes.somespace(nextnext,true)
+                                    if somespace then
+                                        if trace_hspacing then
+                                            logs.report("spacing","removing penalty and space after %s", utfchar(start.char))
+                                        end
+                                        head, _ = remove_node(head,next,true)
+                                        head, _ = remove_node(head,nextnext,true)
+                                    end
+                                else
+                                    local somespace = nodes.somespace(next,true)
+                                    if somespace then
+                                        if trace_hspacing then
+                                            logs.report("spacing","removing space after %s", utfchar(start.char))
+                                        end
+                                        head, _ = remove_node(head,next,true)
+                                    end
+                                end
+                                ok = true
+                            else
+                                ok = not (nodes.somepenalty(next,10000) and nodes.somespace(next.next,true)) or nodes.somespace(next,true)
+                            end
+                            if ok then
+                                if trace_hspacing then
+                                    logs.report("spacing","inserting penalty and space after %s", utfchar(start.char))
+                                end
+                                insert_node_after(head,start,make_glue_node(tex.scale(quad,right)))
+                                insert_node_after(head,start,make_penalty_node(10000))
+                                done = true
+                            end
+                        end
+                    end
+                end
+            end
+        end
+        start = start.next
+    end
+    return head, done
+end
+
+lists.handle_spacing = nodes.install_attribute_handler {
+    name      = "spacing",
+    namespace = spacings,
+    processor = spacings.process,
+}
+
+function spacings.enable()
+    tasks.enableaction("processors","lists.handle_spacing")
+end
+
+--~ local data = {
+--~     name      = "spacing",
+--~     namespace = spacings,
+--~     processor = spacings.process,
+--~ }
+--~ nodes.process_attribute = process_attribute
+--~ function lists.handle_spacing(head)
+--~     return process_attribute(head,data)
+--~ end