Initial commit of glTF 2.0 importer/exporter

Official Khronos Group Blender glTF 2.0 importer and exporter.

glTF specification: https://github.com/KhronosGroup/glTF
The upstream repository can be found here:
https://github.com/KhronosGroup/glTF-Blender-IO

Reviewed By: Bastien, Campbell

Differential Revision: https://developer.blender.org/D3929

1 files changed, 200 insertions, 0 deletions

diff --git a/io_scene_gltf2/blender/exp/gltf2_blender_gather_primitives.py b/io_scene_gltf2/blender/exp/gltf2_blender_gather_primitives.py
new file mode 100755
index 00000000..5b3e607b
--- /dev/null
+++ b/io_scene_gltf2/blender/exp/gltf2_blender_gather_primitives.py
@@ -0,0 +1,200 @@
+# 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 bpy
+from typing import List, Optional
+
+from .gltf2_blender_export_keys import INDICES, FORCE_INDICES, NORMALS, MORPH_NORMAL, TANGENTS, MORPH_TANGENT, MORPH
+
+from io_scene_gltf2.blender.exp.gltf2_blender_gather_cache import cached
+from io_scene_gltf2.blender.exp import gltf2_blender_extract
+from io_scene_gltf2.blender.exp import gltf2_blender_gather_primitive_attributes
+from io_scene_gltf2.blender.exp import gltf2_blender_utils
+from io_scene_gltf2.blender.exp import gltf2_blender_gather_materials
+
+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.io.com.gltf2_io_debug import print_console
+
+
+@cached
+def gather_primitives(
+        blender_mesh: bpy.types.Mesh,
+        vertex_groups: Optional[bpy.types.VertexGroups],
+        modifiers: Optional[bpy.types.ObjectModifiers],
+        export_settings
+        ) -> List[gltf2_io.MeshPrimitive]:
+    """
+    Extract the mesh primitives from a blender object
+
+    :return: a list of glTF2 primitives
+    """
+    primitives = []
+    blender_primitives = gltf2_blender_extract.extract_primitives(
+        None, blender_mesh, vertex_groups, modifiers, export_settings)
+
+    for internal_primitive in blender_primitives:
+
+        primitive = gltf2_io.MeshPrimitive(
+            attributes=__gather_attributes(internal_primitive, blender_mesh, modifiers, export_settings),
+            extensions=None,
+            extras=None,
+            indices=__gather_indices(internal_primitive, blender_mesh, modifiers, export_settings),
+            material=__gather_materials(internal_primitive, blender_mesh, modifiers, export_settings),
+            mode=None,
+            targets=__gather_targets(internal_primitive, blender_mesh, modifiers, export_settings)
+        )
+        primitives.append(primitive)
+
+    return primitives
+
+
+def __gather_materials(blender_primitive, blender_mesh, modifiers, export_settings):
+    if not blender_primitive['material']:
+        # TODO: fix 'extract_promitives' so that the value of 'material' is None and not empty string
+        return None
+    material = bpy.data.materials[blender_primitive['material']]
+    return gltf2_blender_gather_materials.gather_material(material, export_settings)
+
+
+def __gather_indices(blender_primitive, blender_mesh, modifiers, export_settings):
+    indices = blender_primitive['indices']
+
+    max_index = max(indices)
+    if max_index < (1 << 8):
+        component_type = gltf2_io_constants.ComponentType.UnsignedByte
+    elif max_index < (1 << 16):
+        component_type = gltf2_io_constants.ComponentType.UnsignedShort
+    elif max_index < (1 << 32):
+        component_type = gltf2_io_constants.ComponentType.UnsignedInt
+    else:
+        print_console('ERROR', 'Invalid max_index: ' + str(max_index))
+        return None
+
+    if export_settings[FORCE_INDICES]:
+        component_type = gltf2_io_constants.ComponentType.from_legacy_define(export_settings[INDICES])
+
+    element_type = gltf2_io_constants.DataType.Scalar
+    binary_data = gltf2_io_binary_data.BinaryData.from_list(indices, component_type)
+    return gltf2_io.Accessor(
+        buffer_view=binary_data,
+        byte_offset=None,
+        component_type=component_type,
+        count=len(indices) // gltf2_io_constants.DataType.num_elements(element_type),
+        extensions=None,
+        extras=None,
+        max=None,
+        min=None,
+        name=None,
+        normalized=None,
+        sparse=None,
+        type=element_type
+    )
+
+
+def __gather_attributes(blender_primitive, blender_mesh, modifiers, export_settings):
+    return gltf2_blender_gather_primitive_attributes.gather_primitive_attributes(blender_primitive, export_settings)
+
+
+def __gather_targets(blender_primitive, blender_mesh, modifiers, export_settings):
+    if export_settings[MORPH]:
+        targets = []
+        if blender_mesh.shape_keys is not None:
+            morph_index = 0
+            for blender_shape_key in blender_mesh.shape_keys.key_blocks:
+                if blender_shape_key != blender_shape_key.relative_key:
+
+                    target_position_id = 'MORPH_POSITION_' + str(morph_index)
+                    target_normal_id = 'MORPH_NORMAL_' + str(morph_index)
+                    target_tangent_id = 'MORPH_TANGENT_' + str(morph_index)
+
+                    if blender_primitive["attributes"].get(target_position_id):
+                        target = {}
+                        internal_target_position = blender_primitive["attributes"][target_position_id]
+                        binary_data = gltf2_io_binary_data.BinaryData.from_list(
+                            internal_target_position,
+                            gltf2_io_constants.ComponentType.Float
+                        )
+                        target["POSITION"] = gltf2_io.Accessor(
+                            buffer_view=binary_data,
+                            byte_offset=None,
+                            component_type=gltf2_io_constants.ComponentType.Float,
+                            count=len(internal_target_position) // gltf2_io_constants.DataType.num_elements(
+                                gltf2_io_constants.DataType.Vec3),
+                            extensions=None,
+                            extras=None,
+                            max=gltf2_blender_utils.max_components(
+                                internal_target_position, gltf2_io_constants.DataType.Vec3),
+                            min=gltf2_blender_utils.min_components(
+                                internal_target_position, gltf2_io_constants.DataType.Vec3),
+                            name=None,
+                            normalized=None,
+                            sparse=None,
+                            type=gltf2_io_constants.DataType.Vec3
+                        )
+
+                        if export_settings[NORMALS] \
+                                and export_settings[MORPH_NORMAL] \
+                                and blender_primitive["attributes"].get(target_normal_id):
+
+                            internal_target_normal = blender_primitive["attributes"][target_normal_id]
+                            binary_data = gltf2_io_binary_data.BinaryData.from_list(
+                                internal_target_normal,
+                                gltf2_io_constants.ComponentType.Float,
+                            )
+                            target['NORMAL'] = gltf2_io.Accessor(
+                                buffer_view=binary_data,
+                                byte_offset=None,
+                                component_type=gltf2_io_constants.ComponentType.Float,
+                                count=len(internal_target_normal) // gltf2_io_constants.DataType.num_elements(
+                                    gltf2_io_constants.DataType.Vec3),
+                                extensions=None,
+                                extras=None,
+                                max=None,
+                                min=None,
+                                name=None,
+                                normalized=None,
+                                sparse=None,
+                                type=gltf2_io_constants.DataType.Vec3
+                            )
+
+                        if export_settings[TANGENTS] \
+                                and export_settings[MORPH_TANGENT] \
+                                and blender_primitive["attributes"].get(target_tangent_id):
+                            internal_target_tangent = blender_primitive["attributes"][target_tangent_id]
+                            binary_data = gltf2_io_binary_data.BinaryData.from_list(
+                                internal_target_tangent,
+                                gltf2_io_constants.ComponentType.Float,
+                            )
+                            target['TANGENT'] = gltf2_io.Accessor(
+                                buffer_view=binary_data,
+                                byte_offset=None,
+                                component_type=gltf2_io_constants.ComponentType.Float,
+                                count=len(internal_target_tangent) // gltf2_io_constants.DataType.num_elements(
+                                    gltf2_io_constants.DataType.Vec3),
+                                extensions=None,
+                                extras=None,
+                                max=None,
+                                min=None,
+                                name=None,
+                                normalized=None,
+                                sparse=None,
+                                type=gltf2_io_constants.DataType.Vec3
+                            )
+                        targets.append(target)
+                        morph_index += 1
+        return targets
+    return None
+