io_scene_gltf2/blender/imp/gltf2_blender_animation_weight.py

   1 # SPDX-FileCopyrightText: 2018-2021 The glTF-Blender-IO authors
   2 #
   3 # SPDX-License-Identifier: Apache-2.0
   4
   5 import bpy
   6
   7 from ...io.imp.gltf2_io_user_extensions import import_user_extensions
   8 from ...io.imp.gltf2_io_binary import BinaryData
   9 from .gltf2_blender_animation_utils import make_fcurve
  10
  11
  12 class BlenderWeightAnim():
  13     """Blender ShapeKey Animation."""
  14     def __new__(cls, *args, **kwargs):
  15         raise RuntimeError("%s should not be instantiated" % cls)
  16
  17     @staticmethod
  18     def anim(gltf, anim_idx, vnode_id):
  19         """Manage animation."""
  20         vnode = gltf.vnodes[vnode_id]
  21
  22         node_idx = vnode.mesh_node_idx
  23
  24         import_user_extensions('gather_import_animation_weight_before_hook', gltf, vnode, gltf.data.animations[anim_idx])
  25
  26         if node_idx is None:
  27             return
  28
  29         node = gltf.data.nodes[node_idx]
  30         obj = vnode.blender_object
  31         fps = (bpy.context.scene.render.fps * bpy.context.scene.render.fps_base)
  32
  33         animation = gltf.data.animations[anim_idx]
  34
  35         if anim_idx not in node.animations.keys():
  36             return
  37
  38         for channel_idx in node.animations[anim_idx]:
  39             channel = animation.channels[channel_idx]
  40             if channel.target.path == "weights":
  41                 break
  42             if channel.target.path == "pointer":
  43                 pointer_tab = channel.target.extensions["KHR_animation_pointer"]["pointer"].split("/")
  44                 if len(pointer_tab) >= 4 and pointer_tab[1] in ["nodes", "meshes"] and pointer_tab[3] == "weights":
  45                     break
  46         else:
  47             return
  48
  49         name = animation.track_name + "_" + obj.name
  50         action = bpy.data.actions.new(name)
  51         action.id_root = "KEY"
  52         gltf.needs_stash.append((obj.data.shape_keys, action))
  53
  54         keys = BinaryData.get_data_from_accessor(gltf, animation.samplers[channel.sampler].input)
  55         values = BinaryData.get_data_from_accessor(gltf, animation.samplers[channel.sampler].output)
  56
  57         # retrieve number of targets
  58         pymesh = gltf.data.meshes[gltf.data.nodes[node_idx].mesh]
  59         nb_targets = len(pymesh.shapekey_names)
  60
  61         if animation.samplers[channel.sampler].interpolation == "CUBICSPLINE":
  62             offset = nb_targets
  63             stride = 3 * nb_targets
  64         else:
  65             offset = 0
  66             stride = nb_targets
  67
  68         coords = [0] * (2 * len(keys))
  69         coords[::2] = (key[0] * fps for key in keys)
  70
  71         for sk in range(nb_targets):
  72             if pymesh.shapekey_names[sk] is not None: # Do not animate shapekeys not created
  73                 coords[1::2] = (values[offset + stride * i + sk][0] for i in range(len(keys)))
  74                 kb_name = pymesh.shapekey_names[sk]
  75                 data_path = 'key_blocks["%s"].value' % bpy.utils.escape_identifier(kb_name)
  76
  77                 make_fcurve(
  78                     action,
  79                     coords,
  80                     data_path=data_path,
  81                     group_name="ShapeKeys",
  82                     interpolation=animation.samplers[channel.sampler].interpolation,
  83                 )
  84
  85                 # Expand weight range if needed
  86                 kb = obj.data.shape_keys.key_blocks[kb_name]
  87                 min_weight = min(coords[1:2])
  88                 max_weight = max(coords[1:2])
  89                 if min_weight < kb.slider_min: kb.slider_min = min_weight
  90                 if max_weight > kb.slider_max: kb.slider_max = max_weight
  91
  92         import_user_extensions('gather_import_animation_weight_after_hook', gltf, vnode, animation)