summaryrefslogtreecommitdiff
path: root/tex/context/base/page-str.lua
blob: 35ce85609c470035ee5a547e2aa933be4321eb2c (plain)
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
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
if not modules then modules = { } end modules ['page-str'] = {
    version   = 1.001,
    comment   = "companion to page-str.mkiv",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

-- streams -> managers.streams

-- work in progresss .. unfinished

local concat, insert, remove = table.concat, table.insert, table.remove

local nodes, node = nodes, node

local nodepool          = nodes.pool
local tasks             = nodes.tasks

local new_kern          = nodepool.kern
local new_glyph         = nodepool.glyph

local find_tail         = node.slide
local write_node        = node.write
local free_node         = node.free
local copy_nodelist     = node.copy_list
local vpack_nodelist    = node.vpack
local hpack_nodelist    = node.hpack

local settings_to_array = utilities.parsers.settings_to_array

local texgetdimen       = tex.getdimen
local texgetbox         = tex.getbox

local trace_collecting = false  trackers.register("streams.collecting", function(v) trace_collecting = v end)
local trace_flushing   = false  trackers.register("streams.flushing",   function(v) trace_flushing   = v end)

local report_streams = logs.reporter("streams")

streams       = streams or { } -- might move to the builders namespace
local streams = streams

local data, name, stack = { }, nil, { }

function streams.enable(newname)
    if newname == "default" then
        name = nil
    else
        name = newname
    end
end

function streams.disable()
    name = stack[#stack]
end

function streams.start(newname)
    insert(stack,name)
    name = newname
end

function streams.stop(newname)
    name = remove(stack)
end

function streams.collect(head,where)
    if name and head and name ~= "default" then
        local tail = node.slide(head)
        local dana = data[name]
        if not dana then
            dana = { }
            data[name] = dana
        end
        local last = dana[#dana]
        if last then
            local tail = find_tail(last)
            tail.next, head.prev = head, tail
        elseif last == false then
            dana[#dana] = head
        else
            dana[1] = head
        end
        if trace_collecting then
            report_streams("appending snippet %a to slot %s",name,#dana)
        end
        return nil, true
    else
        return head, false
    end
end

function streams.push(thename)
    if not thename or thename == "" then
        thename = name
    end
    if thename and thename ~= "" then
        local dana = data[thename]
        if dana then
            dana[#dana+1] = false
            if trace_collecting then
                report_streams("pushing snippet %a",thename)
            end
        end
    end
end

function streams.flush(name,copy) -- problem: we need to migrate afterwards
    local dana = data[name]
    if dana then
        local dn = #dana
        if dn == 0 then
            -- nothing to flush
        elseif copy then
            if trace_flushing then
                report_streams("flushing copies of %s slots of %a",dn,name)
            end
            for i=1,dn do
                local di = dana[i]
                if di then
                    write_node(copy_nodelist(di.list)) -- list, will be option
                end
            end
            if copy then
                data[name] = nil
            end
        else
            if trace_flushing then
                report_streams("flushing %s slots of %a",dn,name)
            end
            for i=1,dn do
                local di = dana[i]
                if di then
                    write_node(di.list) -- list, will be option
                    di.list = nil
                    free_node(di)
                end
            end
        end
    end
end

function streams.synchronize(list) -- this is an experiment !
    -- we don't optimize this as we want to trace in detail
    list = settings_to_array(list)
    local max = 0
    if trace_flushing then
        report_streams("synchronizing list: % t",list)
    end
    for i=1,#list do
        local dana = data[list[i]]
        if dana then
            local n = #dana
            if n > max then
                max = n
            end
        end
    end
    if trace_flushing then
        report_streams("maximum number of slots: %s",max)
    end
    for m=1,max do
        local height, depth = 0, 0
        for i=1,#list do
            local name = list[i]
            local dana = data[name]
            local slot = dana[m]
            if slot then
                local vbox = vpack_nodelist(slot)
                local ht, dp = vbox.height, vbox.depth
                if ht > height then
                    height = ht
                end
                if dp > depth then
                    depth = dp
                end
                dana[m] = vbox
                if trace_flushing then
                    report_streams("slot %s of %a is packed to height %p and depth %p",m,name,ht,dp)
                end
            end
        end
        if trace_flushing then
            report_streams("slot %s has max height %p and max depth %p",m,height,depth)
        end
        local strutht = texgetdimen("globalbodyfontstrutheight")
        local strutdp = texgetdimen("globalbodyfontstrutdepth")
        local struthtdp = strutht + strutdp
        for i=1,#list do
            local name = list[i]
            local dana = data[name]
            local vbox = dana[m]
            if vbox then
                local delta_height = height - vbox.height
                local delta_depth  = depth  - vbox.depth
                if delta_height > 0 or delta_depth > 0 then
                    if false then
                        -- actually we need to add glue and repack
                        vbox.height, vbox.depth = height, depth
                        if trace_flushing then
                            report_streams("slot %s of %a with delta (%p,%p) is compensated",m,i,delta_height,delta_depth)
                        end
                    else
                        -- this is not yet ok as we also need to keep an eye on vertical spacing
                        -- so we might need to do some splitting or whatever
                        local tail = vbox.list and find_tail(vbox.list)
                        local n, delta = 0, delta_height -- for tracing
                        while delta > 0 do
                            -- we need to add some interline penalties
                            local line = copy_nodelist(texgetbox("strutbox"))
                            line.height, line.depth = strutht, strutdp
                            if tail then
                                tail.next, line.prev = line, tail
                            end
                            tail = line
                            n, delta = n +1, delta - struthtdp
                        end
                        dana[m] = vpack_nodelist(vbox.list)
                        vbox.list = nil
                        free_node(vbox)
                        if trace_flushing then
                            report_streams("slot %s:%s with delta (%p,%p) is compensated by %s lines",m,i,delta_height,delta_depth,n)
                        end
                    end
                end
            else
                -- make dummy
            end
        end
    end
end

tasks.appendaction("mvlbuilders", "normalizers", "streams.collect")

tasks.disableaction("mvlbuilders", "streams.collect")

function streams.initialize()
    tasks.enableaction ("mvlbuilders", "streams.collect")
end

-- todo: remove empty last { }'s