diff options
Diffstat (limited to 'io_scene_gltf2/io/imp/gltf2_io_binary.py')
| -rwxr-xr-x | io_scene_gltf2/io/imp/gltf2_io_binary.py | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/io_scene_gltf2/io/imp/gltf2_io_binary.py b/io_scene_gltf2/io/imp/gltf2_io_binary.py new file mode 100755 index 00000000..5f51d95d --- /dev/null +++ b/io_scene_gltf2/io/imp/gltf2_io_binary.py @@ -0,0 +1,178 @@ +# 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: + 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: + pyimage.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 + |