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
|
# Copyright 2018 The glTF-Blender-IO authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import struct
import base64
from os.path import dirname, join, isfile, basename
class BinaryData():
"""Binary reader."""
def __new__(cls, *args, **kwargs):
raise RuntimeError("%s should not be instantiated" % cls)
@staticmethod
def get_binary_from_accessor(gltf, accessor_idx):
"""Get binary from accessor."""
accessor = gltf.data.accessors[accessor_idx]
bufferView = gltf.data.buffer_views[accessor.buffer_view] # TODO initialize with 0 when not present!
if bufferView.buffer in gltf.buffers.keys():
buffer = gltf.buffers[bufferView.buffer]
else:
# load buffer
gltf.load_buffer(bufferView.buffer)
buffer = gltf.buffers[bufferView.buffer]
accessor_offset = accessor.byte_offset
bufferview_offset = bufferView.byte_offset
if accessor_offset is None:
accessor_offset = 0
if bufferview_offset is None:
bufferview_offset = 0
return buffer[accessor_offset + bufferview_offset:accessor_offset + bufferview_offset + bufferView.byte_length]
@staticmethod
def get_data_from_accessor(gltf, accessor_idx):
"""Get data from accessor."""
accessor = gltf.data.accessors[accessor_idx]
bufferView = gltf.data.buffer_views[accessor.buffer_view] # TODO initialize with 0 when not present!
buffer_data = BinaryData.get_binary_from_accessor(gltf, accessor_idx)
fmt_char = gltf.fmt_char_dict[accessor.component_type]
component_nb = gltf.component_nb_dict[accessor.type]
fmt = '<' + (fmt_char * component_nb)
stride_ = struct.calcsize(fmt)
# TODO data alignment stuff
if bufferView.byte_stride:
stride = bufferView.byte_stride
else:
stride = stride_
data = []
offset = 0
while len(data) < accessor.count:
element = struct.unpack_from(fmt, buffer_data, offset)
data.append(element)
offset += stride
if accessor.sparse:
sparse_indices_data = BinaryData.get_data_from_sparse(gltf, accessor.sparse, "indices")
sparse_values_values = BinaryData.get_data_from_sparse(
gltf,
accessor.sparse,
"values",
accessor.type,
accessor.component_type
)
# apply sparse
for cpt_idx, idx in enumerate(sparse_indices_data):
data[idx[0]] = sparse_values_values[cpt_idx]
# Normalization
if accessor.normalized:
for idx, tuple in enumerate(data):
new_tuple = ()
for i in tuple:
if accessor.component_type == 5120:
new_tuple += (max(float(i / 127.0 ), -1.0),)
elif accessor.component_type == 5121:
new_tuple += (float(i / 255.0),)
elif accessor.component_type == 5122:
new_tuple += (max(float(i / 32767.0), -1.0),)
elif accessor.component_type == 5123:
new_tuple += (i / 65535.0,)
else:
new_tuple += (float(i),)
data[idx] = new_tuple
return data
@staticmethod
def get_data_from_sparse(gltf, sparse, type_, type_val=None, comp_type=None):
"""Get data from sparse."""
if type_ == "indices":
bufferView = gltf.data.buffer_views[sparse.indices.buffer_view]
offset = sparse.indices.byte_offset
component_nb = gltf.component_nb_dict['SCALAR']
fmt_char = gltf.fmt_char_dict[sparse.indices.component_type]
elif type_ == "values":
bufferView = gltf.data.buffer_views[sparse.values.buffer_view]
offset = sparse.values.byte_offset
component_nb = gltf.component_nb_dict[type_val]
fmt_char = gltf.fmt_char_dict[comp_type]
if bufferView.buffer in gltf.buffers.keys():
buffer = gltf.buffers[bufferView.buffer]
else:
# load buffer
gltf.load_buffer(bufferView.buffer)
buffer = gltf.buffers[bufferView.buffer]
bin_data = buffer[bufferView.byte_offset + offset:bufferView.byte_offset + offset + bufferView.byte_length]
fmt = '<' + (fmt_char * component_nb)
stride_ = struct.calcsize(fmt)
# TODO data alignment stuff ?
if bufferView.byte_stride:
stride = bufferView.byte_stride
else:
stride = stride_
data = []
offset = 0
while len(data) < sparse.count:
element = struct.unpack_from(fmt, bin_data, offset)
data.append(element)
offset += stride
return data
@staticmethod
def get_image_data(gltf, img_idx):
"""Get data from image."""
pyimage = gltf.data.images[img_idx]
image_name = "Image_" + str(img_idx)
if pyimage.uri:
sep = ';base64,'
if pyimage.uri[:5] == 'data:':
idx = pyimage.uri.find(sep)
if idx != -1:
data = pyimage.uri[idx + len(sep):]
return base64.b64decode(data), image_name
if isfile(join(dirname(gltf.filename), pyimage.uri)):
with open(join(dirname(gltf.filename), pyimage.uri), 'rb') as f_:
return f_.read(), basename(join(dirname(gltf.filename), pyimage.uri))
else:
gltf.log.error("Missing file (index " + str(img_idx) + "): " + pyimage.uri)
return None, None
if pyimage.buffer_view is None:
return None, None
bufferView = gltf.data.buffer_views[pyimage.buffer_view]
if bufferView.buffer in gltf.buffers.keys():
buffer = gltf.buffers[bufferView.buffer]
else:
# load buffer
gltf.load_buffer(bufferView.buffer)
buffer = gltf.buffers[bufferView.buffer]
bufferview_offset = bufferView.byte_offset
if bufferview_offset is None:
bufferview_offset = 0
return buffer[bufferview_offset:bufferview_offset + bufferView.byte_length], image_name
|