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-rw-r--r--Master/texmf-dist/tex/context/base/attr-eff.lua97
1 files changed, 97 insertions, 0 deletions
diff --git a/Master/texmf-dist/tex/context/base/attr-eff.lua b/Master/texmf-dist/tex/context/base/attr-eff.lua
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+++ b/Master/texmf-dist/tex/context/base/attr-eff.lua
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+if not modules then modules = { } end modules ['attr-eff'] = {
+ version = 1.001,
+ comment = "companion to attr-eff.mkiv",
+ author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+ copyright = "PRAGMA ADE / ConTeXt Development Team",
+ license = "see context related readme files"
+}
+
+local format = string.format
+
+local attributes, nodes = attributes, nodes
+
+local states = attributes.states
+local tasks = nodes.tasks
+local nodeinjections = backends.nodeinjections
+local settexattribute = tex.setattribute
+local allocate = utilities.storage.allocate
+local setmetatableindex = table.setmetatableindex
+
+attributes.effects = attributes.effects or { }
+local effects = attributes.effects
+
+local a_effect = attributes.private('effect')
+
+effects.data = allocate()
+effects.values = effects.values or { }
+effects.registered = effects.registered or { }
+effects.attribute = a_effect
+
+storage.register("attributes/effects/registered", effects.registered, "attributes.effects.registered")
+storage.register("attributes/effects/values", effects.values, "attributes.effects.values")
+
+local template = "%s:%s:%s"
+
+local data = effects.data
+local registered = effects.registered
+local values = effects.values
+
+-- valid effects: normal inner outer both hidden (stretch,rulethickness,effect)
+
+local function effect(...) effect = nodeinjections.effect return effect(...) end
+
+local function extender(effects,key)
+ if key == "none" then
+ local d = effect(0,0,0)
+ effects.none = d
+ return d
+ end
+end
+
+local function reviver(data,n)
+ local e = values[n] -- we could nil values[n] now but hardly needed
+ local d = effect(e[1],e[2],e[3])
+ data[n] = d
+ return d
+end
+
+setmetatableindex(effects, extender)
+setmetatableindex(effects.data, reviver)
+
+effects.handler = nodes.installattributehandler {
+ name = "effect",
+ namespace = effects,
+ initializer = states.initialize,
+ finalizer = states.finalize,
+ processor = states.process,
+}
+
+local function register(effect,stretch,rulethickness)
+ local stamp = format(template,effect,stretch,rulethickness)
+ local n = registered[stamp]
+ if not n then
+ n = #values + 1
+ values[n] = { effect, stretch, rulethickness }
+ registered[stamp] = n
+ end
+ return n
+end
+
+local function enable()
+ tasks.enableaction("shipouts","attributes.effects.handler")
+end
+
+effects.register = register
+effects.enable = enable
+
+-- interface
+
+local enabled = false
+
+function commands.triggereffect(effect,stretch,rulethickness)
+ if not enabled then
+ enable()
+ enabled = true
+ end
+ settexattribute(a_effect,register(effect,stretch,rulethickness))
+end