1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
if not modules then modules = { } end modules ['typo-drp'] = {
version = 1.001,
comment = "companion to typo-drp.mkiv",
author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
-- A playground for experiments. Currently we only have a dropped caps as special
-- but there might be more, so for the moment we keep this 'paragraphs' namespace
-- for this.
local tonumber, type, next = tonumber, type, next
local ceil = math.ceil
local utfbyte = utf.byte
local utfchar = utf.char
local trace_initials = false trackers.register("typesetters.initials", function(v) trace_initials = v end)
local report_initials = logs.reporter("nodes","initials")
local initials = typesetters.paragraphs or { }
typesetters.initials = initials or { }
local nodes = nodes
local tasks = nodes.tasks
local hpack_nodes = nodes.hpack
local nodecodes = nodes.nodecodes
local whatsitcodes = nodes.whatsitcodes
local new_kern = nodes.pool.kern
local insert_before = nodes.insert_before
local insert_after = nodes.insert_after
local variables = interfaces.variables
local v_default = variables.default
local v_margin = variables.margin
local texget = tex.get
local texsetattribute = tex.setattribute
local unsetvalue = attributes.unsetvalue
local glyph_code = nodecodes.glyph
local hlist_code = nodecodes.hlist
local kern_node = nodecodes.kern
local whatsit_code = nodecodes.whatsit
local localpar_code = whatsitcodes.localpar
local actions = { }
initials.actions = actions
local a_initial = attributes.private("initial")
local a_color = attributes.private('color')
local a_transparency = attributes.private('transparency')
local a_colorspace = attributes.private('colormodel')
local settings = nil
function initials.set(specification)
settings = specification or { }
settings.enabled = true
tasks.enableaction("processors","typesetters.initials.handler")
if trace_initials then
report_initials("enabling initials")
end
texsetattribute(a_initial,1)
end
commands.setinitial = initials.set
-- dropped caps experiment (will be done properly when luatex
-- stores the state in the local par node) .. btw, search still
-- works with dropped caps, as does an export
-- we need a 'par' attribute and in fact for dropped caps we don't need
-- need an attribute ... dropit will become s state counter (or end up
-- in the localpar user data
-- for the moment, each paragraph gets a number as id (attribute) ..problem
-- with nesting .. or anyhow, needed for tagging anyway
-- todo: prevent linebreak .. but normally a initial ends up at the top of
-- a page so this has a low priority
actions[v_default] = function(head,setting)
local done = false
if head.id == whatsit_code and head.subtype == localpar_code then
-- begin of par
local first = head.next
-- parbox .. needs to be set at 0
if first and first.id == hlist_code then
first = first.next
end
-- we need to skip over kerns and glues (signals)
while first and first.id ~= glyph_code do
first = first.next
end
if first and first.id == glyph_code then
local char = first.char
local prev = first.prev
local next = first.next
-- if prev.id == hlist_code then
-- -- set the width to 0
-- end
if next and next.id == kern_node then
next.kern = 0
end
if setting.font then
first.font = setting.font
end
-- can be a helper
local ma = setting.ma or 0
local ca = setting.ca
local ta = setting.ta
if ca and ca > 0 then
first[a_colorspace] = ma == 0 and 1 or ma
first[a_color] = ca
end
if ta and ta > 0 then
first[a_transparency] = ta
end
--
local width = first.width
local height = first.height
local depth = first.depth
local distance = setting.distance or 0
local voffset = setting.voffset or 0
local hoffset = setting.hoffset or 0
first.xoffset = - width - hoffset - distance - parindent
first.yoffset = - height - voffset
if true then
-- needed till we can store parindent with localpar
first.prev = nil
first.next = nil
local h = hpack_nodes(first)
h.width = 0
h.height = 0
h.depth = 0
prev.next = h
next.prev = h
h.next = next
h.prev = prev
end
if setting.location == v_margin then
-- okay
else
local lines = tonumber(setting.n) or 0
if lines == 0 then -- safeguard, not too precise
lines = ceil((height+voffset) / texget("baselineskip").width)
end
-- We cannot set parshape yet ... when we can I'll add a slope
-- option (positive and negative, in emwidth).
local hangafter = - lines
local hangindent = width + distance + parindent
if trace_initials then
report_initials("setting hangafter to %i and hangindent to %p",hangafter,hangindent)
end
tex.hangafter = hangafter
tex.hangindent = hangindent
if parindent ~= 0 then
insert_after(first,first,new_kern(-parindent))
end
end
done = true
end
end
return head, done
end
local function process(namespace,attribute,head)
local start = head
local attr = nil
while start do
attr = start[attribute]
if attr then
break
elseif start.id == glyph then
break
else
start = start.next
end
end
if attr then
-- here as we can process nested boxes first so we need to keep state
tasks.disableaction("processors","typesetters.initials.handler")
-- texsetattribute(attribute,unsetvalue)
local alternative = settings.alternative or v_default
local action = actions[alternative] or actions[v_default]
if action then
if trace_initials then
report_initials("processing initials, alternative %a",alternative)
end
local head, done = action(head,settings)
return head, done
end
end
return head, false
end
initials.attribute = a_initial
initials.handler = nodes.installattributehandler {
name = "initials",
namespace = initials,
processor = process,
}
|