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
|
class PSDLayerMask
constructor: (@file, @header, @options) ->
# Array to hold all of the layers
@layers = []
# Does the first alpha channel contain the transparency data?
@mergedAlpha = false
# The global layer mask
@globalMask = {}
# Additional layer information
@extras = []
# Skip over this section and don't parse it
skip: -> @file.seek @file.readInt()
parse: ->
# Read the size of the entire layers and masks section
maskSize = @file.readInt()
endLoc = @file.tell() + maskSize
Log.debug "Layer mask size is #{maskSize}"
# If the mask size is > 0, then parse the section. Otherwise,
# this section doesn't exist and the whole layers/masks data
# is 4 bytes (the length we've already read)
return if maskSize <= 0
# Size of the layer info section. 4 bytes, rounded up by 2's.
layerInfoSize = Util.pad2 @file.readInt()
# Store the current position in case we need to bail
# and skip over this section.
pos = @file.tell()
# If the layer info size is > 0, then we have some layers
if layerInfoSize > 0
# Read the number of layers, 2 bytes.
@numLayers = @file.readShortInt()
# If the number of layers is negative, the absolute value is
# the actual number of layers, and the first alpha channel contains
# the transparency data for the merged image.
if @numLayers < 0
Log.debug "Note: first alpha channel contains transparency data"
@numLayers = Math.abs @numLayers
@mergedAlpha = true
if @numLayers * (18 + 6 * @header.channels) > layerInfoSize
throw "Unlikely number of #{@numLayers} layers for #{@header['channels']} with #{layerInfoSize} layer info size. Giving up."
Log.debug "Found #{@numLayers} layer(s)"
for i in [0...@numLayers]
layer = new PSDLayer @file
layer.parse(i)
@layers.push layer
for layer in @layers
if layer.isFolder or layer.isHidden
# Layer contains no image data. Skip ahead.
@file.seek 8
continue
layer.image = new PSDChannelImage(@file, @header, layer)
if @options.layerImages and (
(@options.onlyVisibleLayers and layer.visible) or
!@options.onlyVisibleLayers
)
layer.image.parse()
else
layer.image.skip()
# Layers are parsed in reverse order
@layers.reverse()
@groupLayers()
# In case there are filler zeros
@file.seek pos + layerInfoSize, false
# Parse the global layer mask
@parseGlobalMask()
# Temporarily skip the rest of layers & masks section
@file.seek endLoc, false
return
# We have more additional info to parse, especially beacuse this is PS >= 4.0
#@parseExtraInfo(endLoc) if @file.tell() < endLoc
parseGlobalMask: ->
length = @file.readInt()
return if length is 0
start = @file.tell()
end = @file.tell() + length
Log.debug "Global mask length: #{length}"
# Undocumented
@globalMask.overlayColorSpace = @file.readShortInt()
# TODO: parse color space components into actual color.
@globalMask.colorComponents = []
for i in [0...4]
@globalMask.colorComponents.push(@file.readShortInt() >> 8)
# 0 = transparent, 100 = opaque
@globalMask.opacity = @file.readShortInt()
# 0 = color selected; 1 = color protected; 128 = use value per layer
@globalMask.kind = @file.read(1)[0]
Log.debug "Global mask:", @globalMask
# Filler zeros, seek to end.
@file.seek end, false
parseExtraInfo: (end) ->
while @file.tell() < end
# Temporary
[
sig,
key,
length
] = @file.readf ">4s4sI"
length = Util.pad2 length
Log.debug "Layer extra:", sig, key, length
@file.seek length
groupLayers: ->
groupLayer = null
for layer in @layers
if layer.isFolder
groupLayer = layer
else if layer.isHidden
groupLayer = null
else
layer.groupLayer = groupLayer
toJSON: ->
data =
mergedAlpha: @mergedAlpha
globalMask: @globalMask
extraInfo: @extras
numLayers: @numLayers
layers: []
for layer in @layers
data.layers.push layer.toJSON()
data
|
