diff options
Diffstat (limited to 'io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py')
| -rwxr-xr-x | io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py new file mode 100755 index 00000000..84703414 --- /dev/null +++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_skins.py @@ -0,0 +1,150 @@ +# 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 mathutils +from . import gltf2_blender_export_keys +from io_scene_gltf2.blender.exp.gltf2_blender_gather_cache import cached +from io_scene_gltf2.io.com import gltf2_io +from io_scene_gltf2.io.exp import gltf2_io_binary_data +from io_scene_gltf2.io.com import gltf2_io_constants +from io_scene_gltf2.blender.exp import gltf2_blender_gather_joints +from io_scene_gltf2.blender.com import gltf2_blender_math + + +@cached +def gather_skin(blender_object, export_settings): + """ + Gather armatures, bones etc into a glTF2 skin object. + + :param blender_object: the object which may contain a skin + :param export_settings: + :return: a glTF2 skin object + """ + if not __filter_skin(blender_object, export_settings): + return None + + return gltf2_io.Skin( + extensions=__gather_extensions(blender_object, export_settings), + extras=__gather_extras(blender_object, export_settings), + inverse_bind_matrices=__gather_inverse_bind_matrices(blender_object, export_settings), + joints=__gather_joints(blender_object, export_settings), + name=__gather_name(blender_object, export_settings), + skeleton=__gather_skeleton(blender_object, export_settings) + ) + + +def __filter_skin(blender_object, export_settings): + if not export_settings[gltf2_blender_export_keys.SKINS]: + return False + if blender_object.type != 'ARMATURE' or len(blender_object.pose.bones) == 0: + return False + + return True + + +def __gather_extensions(blender_object, export_settings): + return None + + +def __gather_extras(blender_object, export_settings): + return None + + +def __gather_inverse_bind_matrices(blender_object, export_settings): + inverse_matrices = [] + + axis_basis_change = mathutils.Matrix.Identity(4) + if export_settings[gltf2_blender_export_keys.YUP]: + axis_basis_change = mathutils.Matrix( + ((1.0, 0.0, 0.0, 0.0), (0.0, 0.0, 1.0, 0.0), (0.0, -1.0, 0.0, 0.0), (0.0, 0.0, 0.0, 1.0))) + + # # artificial torso, as needed by glTF + # inverse_bind_matrix = blender_object.matrix_world.inverted() * axis_basis_change.inverted() + # for column in range(0, 4): + # for row in range(0, 4): + # inverse_matrices.append(inverse_bind_matrix[row][column]) + + # + for blender_bone in blender_object.pose.bones: + inverse_bind_matrix = gltf2_blender_math.multiply(axis_basis_change, blender_bone.bone.matrix_local) + bind_shape_matrix = gltf2_blender_math.multiply(gltf2_blender_math.multiply( + axis_basis_change, blender_object.matrix_world.inverted()), axis_basis_change.inverted()) + + inverse_bind_matrix = gltf2_blender_math.multiply(inverse_bind_matrix.inverted(), bind_shape_matrix) + for column in range(0, 4): + for row in range(0, 4): + inverse_matrices.append(inverse_bind_matrix[row][column]) + + binary_data = gltf2_io_binary_data.BinaryData.from_list(inverse_matrices, gltf2_io_constants.ComponentType.Float) + return gltf2_io.Accessor( + buffer_view=binary_data, + byte_offset=None, + component_type=gltf2_io_constants.ComponentType.Float, + count=len(inverse_matrices) // gltf2_io_constants.DataType.num_elements(gltf2_io_constants.DataType.Mat4), + extensions=None, + extras=None, + max=None, + min=None, + name=None, + normalized=None, + sparse=None, + type=gltf2_io_constants.DataType.Mat4 + ) + + +def __gather_joints(blender_object, export_settings): + # # the skeletal hierarchy groups below a 'root' joint + # # TODO: add transform? + # torso = gltf2_io.Node( + # camera=None, + # children=[], + # extensions={}, + # extras=None, + # matrix=[], + # mesh=None, + # name="Skeleton_" + blender_object.name, + # rotation=None, + # scale=None, + # skin=None, + # translation=None, + # weights=None + # ) + + root_joints = [] + # build the hierarchy of nodes out of the bones + for blender_bone in blender_object.pose.bones: + if not blender_bone.parent: + root_joints.append(gltf2_blender_gather_joints.gather_joint(blender_bone, export_settings)) + + # joints is a flat list containing all nodes belonging to the skin + joints = [] + + def __collect_joints(node): + joints.append(node) + for child in node.children: + __collect_joints(child) + for joint in root_joints: + __collect_joints(joint) + + return joints + + +def __gather_name(blender_object, export_settings): + return blender_object.name + + +def __gather_skeleton(blender_object, export_settings): + # In the future support the result of https://github.com/KhronosGroup/glTF/pull/1195 + return None # gltf2_blender_gather_nodes.gather_node(blender_object, export_settings) + |