Rigify: Fix T78463: better support unguligrade animals (horse) setup.

Add support for 5 bone chains to the limbs.paw rig.

Implement a new limbs.rear_paw rig, which provides a three bone IK
mechanism designed to keep the first and third bones nearly parallel
by default (based on a YouTube video by @Pieriko as suggested by
@icappiello).

Implement a limbs.front_paw rig with automation that aims to
keep the angle between second and third bones mostly stable
by default (has influence option), as suitable for front paws.

The horse and wolf metarigs are updated to use these new rig
types, with the horse rig further overhauled by @icappiello.

Maniphest Tasks: T78463

Differential Revision: https://developer.blender.org/D8496

1 files changed, 183 insertions, 289 deletions

diff --git a/rigify/rigs/limbs/rear_paw.py b/rigify/rigs/limbs/rear_paw.py
index 2d6894e1..5c1bf5c8 100644
--- a/rigify/rigs/limbs/rear_paw.py
+++ b/rigify/rigs/limbs/rear_paw.py
@@ -1,300 +1,194 @@
+#====================== BEGIN GPL LICENSE BLOCK ======================
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU General Public License
+#  as published by the Free Software Foundation; either version 2
+#  of the License, or (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software Foundation,
+#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+#======================= END GPL LICENSE BLOCK ========================
+
+# <pep8 compliant>
+
 import bpy
 
-from .paw import Rig as pawRig
+from ...utils.bones import align_bone_roll
+from ...utils.naming import make_derived_name
+from ...utils.misc import map_list
+
+from itertools import count
 
+from ...base_rig import stage
 
-IMPLEMENTATION = True   # Include and set True if Rig is just an implementation for a wrapper class
-                        # add_parameters and parameters_ui are unused for implementation classes
+from .limb_rigs import BaseLimbRig
+from .paw import Rig as pawRig, create_sample as create_paw_sample
 
 
 class Rig(pawRig):
-    pass
+    """Rear paw rig with special IK automation."""
+
+    ####################################################
+    # EXTRA BONES
+    #
+    # mch:
+    #   ik2_stretch, ik2_target
+    #     Three bone IK stretch limit
+    #   ik2_chain[2]
+    #     Second IK system (pre-driving thigh and ik3)
+    #   ik3_chain[2]
+    #     Third IK system (pre-driving heel)
+    #
+    ####################################################
+
+    ####################################################
+    # IK controls
+
+    def get_middle_ik_controls(self):
+        return [self.bones.ctrl.heel]
+
+    def get_ik_fk_position_chains(self):
+        ik_chain, fk_chain = super().get_ik_fk_position_chains()
+        if not self.use_heel2:
+            return [*ik_chain, ik_chain[-1]], [*fk_chain, fk_chain[-1]]
+        return ik_chain, fk_chain
+
+    def get_extra_ik_controls(self):
+        extra = [self.bones.ctrl.heel2] if self.use_heel2 else []
+        return BaseLimbRig.get_extra_ik_controls(self) + extra
+
+    def get_ik_pole_parents(self):
+        return [(self.bones.mch.ik2_target, self.bones.ctrl.ik)]
+
+
+    ####################################################
+    # Heel control
+
+    @stage.parent_bones
+    def parent_heel_control_bone(self):
+        self.set_bone_parent(self.bones.ctrl.heel, self.bones.mch.ik3_chain[-1])
+
+
+    ####################################################
+    # Second IK system (pre-driving thigh)
+
+    use_mch_ik_base = True
+
+    def get_ik2_input_bone(self):
+        return self.bones.ctrl.heel2 if self.use_heel2 else self.bones.mch.toe_socket
+
+    @stage.generate_bones
+    def make_ik2_mch_stretch(self):
+        orgs = self.bones.org.main
+
+        self.bones.mch.ik2_stretch = self.make_ik2_mch_stretch_bone(orgs)
+        self.bones.mch.ik2_target = self.make_ik2_mch_target_bone(orgs)
+
+    def make_ik2_mch_stretch_bone(self, orgs):
+        name = self.copy_bone(orgs[0], make_derived_name(orgs[0], 'mch', '_ik2_stretch'))
+        self.get_bone(name).tail = self.get_bone(orgs[3]).head
+        return name
+
+    def make_ik2_mch_target_bone(self, orgs):
+        return self.copy_bone(orgs[3], make_derived_name(orgs[0], 'mch', '_ik2_target'), scale=1/2)
+
+    @stage.generate_bones
+    def make_ik2_mch_chain(self):
+        orgs = self.bones.org.main
+        chain = map_list(self.make_ik2_mch_bone, count(0), orgs[0:2])
+        self.bones.mch.ik2_chain = chain
+
+        org_bones = map_list(self.get_bone, orgs)
+        chain_bones = map_list(self.get_bone, chain)
+
+        # Extend the base IK control (used in the ik2 chain) with the projected length of org2
+        chain_bones[0].length += org_bones[2].vector.dot(chain_bones[0].vector.normalized())
+        chain_bones[1].head = chain_bones[0].tail
+        chain_bones[1].tail = org_bones[2].tail
+        align_bone_roll(self.obj, chain[1], orgs[1])
+
+    def make_ik2_mch_bone(self, i, org):
+        return self.copy_bone(org, make_derived_name(org, 'mch', '_ik2'))
+
+    @stage.parent_bones
+    def parent_ik2_mch_chain(self):
+        mch = self.bones.mch
+        self.set_bone_parent(mch.ik2_stretch, mch.follow)
+        self.set_bone_parent(mch.ik2_target, self.get_ik2_input_bone())
+        self.set_bone_parent(mch.ik2_chain[0], self.bones.ctrl.ik_base, inherit_scale='AVERAGE')
+        self.parent_bone_chain(mch.ik2_chain, use_connect=True)
+
+    @stage.configure_bones
+    def configure_ik2_mch_chain(self):
+        for i, mch in enumerate(self.bones.mch.ik2_chain):
+            self.configure_ik2_mch_bone(i, mch)
+
+    def configure_ik2_mch_bone(self, i, mch):
+        bone = self.get_bone(mch)
+        bone.ik_stretch = 0.1
+        if i == 1:
+            bone.lock_ik_x = bone.lock_ik_y = bone.lock_ik_z = True
+            setattr(bone, 'lock_ik_' + self.main_axis, False)
+
+    @stage.rig_bones
+    def rig_ik2_mch_chain(self):
+        mch = self.bones.mch
+        input_bone = self.get_ik2_input_bone()
+        head_tail = 1 if self.use_heel2 else 0
+
+        self.rig_ik_mch_stretch_bones(mch.ik2_target, mch.ik2_stretch, input_bone, head_tail, 3)
+        self.rig_ik_mch_end_bone(mch.ik2_chain[-1], mch.ik2_target, self.bones.ctrl.ik_pole)
+
+
+    ####################################################
+    # Third IK system (pre-driving heel control)
+
+    @stage.generate_bones
+    def make_ik3_mch_chain(self):
+        self.bones.mch.ik3_chain = map_list(self.make_ik3_mch_bone, count(0), self.bones.org.main[1:3])
+
+    def make_ik3_mch_bone(self, i, org):
+        return self.copy_bone(org, make_derived_name(org, 'mch', '_ik3'))
+
+    @stage.parent_bones
+    def parent_ik3_mch_chain(self):
+        mch = self.bones.mch
+
+        self.set_bone_parent(mch.ik3_chain[0], mch.ik2_chain[0])
+        self.parent_bone_chain(mch.ik3_chain, use_connect=True)
+
+    @stage.configure_bones
+    def configure_ik3_mch_chain(self):
+        for i, mch in enumerate(self.bones.mch.ik3_chain):
+            self.configure_ik3_mch_bone(i, mch)
+
+    def configure_ik3_mch_bone(self, i, mch):
+        bone = self.get_bone(mch)
+        bone.ik_stretch = 0.1
+        if i == 0:
+            bone.lock_ik_x = bone.lock_ik_y = bone.lock_ik_z = True
+            setattr(bone, 'lock_ik_' + self.main_axis, False)
+
+    @stage.rig_bones
+    def rig_ik3_mch_chain(self):
+        mch = self.bones.mch
+        # Mostly cancel ik2 scaling.
+        self.make_constraint(
+            mch.ik3_chain[0], 'COPY_SCALE', self.bones.ctrl.ik_base,
+            use_make_uniform=True, influence=0.75,
+        )
+        self.make_constraint(mch.ik3_chain[-1], 'IK', mch.ik2_target, chain_count=2)
 
 
 def create_sample(obj):
-    # generated by rigify.utils.write_metarig
-    bpy.ops.object.mode_set(mode='EDIT')
-    arm = obj.data
-
-    bones = {}
-
-    bone = arm.edit_bones.new('thigh.L')
-    bone.head[:] = 0.0291, 0.1181, 0.2460
-    bone.tail[:] = 0.0293, 0.1107, 0.1682
-    bone.roll = 3.1383
-    bone.use_connect = False
-    bones['thigh.L'] = bone.name
-    bone = arm.edit_bones.new('shin.L')
-    bone.head[:] = 0.0293, 0.1107, 0.1682
-    bone.tail[:] = 0.0293, 0.1684, 0.1073
-    bone.roll = 3.1416
-    bone.use_connect = True
-    bone.parent = arm.edit_bones[bones['thigh.L']]
-    bones['shin.L'] = bone.name
-    bone = arm.edit_bones.new('foot.L')
-    bone.head[:] = 0.0293, 0.1684, 0.1073
-    bone.tail[:] = 0.0293, 0.1530, 0.0167
-    bone.roll = 3.1416
-    bone.use_connect = True
-    bone.parent = arm.edit_bones[bones['shin.L']]
-    bones['foot.L'] = bone.name
-    bone = arm.edit_bones.new('r_toe.L')
-    bone.head[:] = 0.0293, 0.1530, 0.0167
-    bone.tail[:] = 0.0293, 0.1224, 0.0167
-    bone.roll = 0.0000
-    bone.use_connect = True
-    bone.parent = arm.edit_bones[bones['foot.L']]
-    bones['r_toe.L'] = bone.name
-    bone = arm.edit_bones.new('r_palm.001.L')
-    bone.head[:] = 0.0220, 0.1457, 0.0123
-    bone.tail[:] = 0.0215, 0.1401, 0.0123
-    bone.roll = 0.0014
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_toe.L']]
-    bones['r_palm.001.L'] = bone.name
-    bone = arm.edit_bones.new('r_palm.002.L')
-    bone.head[:] = 0.0297, 0.1458, 0.0123
-    bone.tail[:] = 0.0311, 0.1393, 0.0123
-    bone.roll = -0.0005
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_toe.L']]
-    bones['r_palm.002.L'] = bone.name
-    bone = arm.edit_bones.new('r_palm.003.L')
-    bone.head[:] = 0.0363, 0.1473, 0.0123
-    bone.tail[:] = 0.0376, 0.1407, 0.0123
-    bone.roll = 0.0000
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_toe.L']]
-    bones['r_palm.003.L'] = bone.name
-    bone = arm.edit_bones.new('r_palm.004.L')
-    bone.head[:] = 0.0449, 0.1501, 0.0123
-    bone.tail[:] = 0.0466, 0.1479, 0.0123
-    bone.roll = -0.0004
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_toe.L']]
-    bones['r_palm.004.L'] = bone.name
-    bone = arm.edit_bones.new('r_index.001.L')
-    bone.head[:] = 0.0215, 0.1367, 0.0087
-    bone.tail[:] = 0.0217, 0.1325, 0.0070
-    bone.roll = -0.3427
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_palm.001.L']]
-    bones['r_index.001.L'] = bone.name
-    bone = arm.edit_bones.new('r_middle.001.L')
-    bone.head[:] = 0.0311, 0.1358, 0.0117
-    bone.tail[:] = 0.0324, 0.1297, 0.0092
-    bone.roll = -1.0029
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_palm.002.L']]
-    bones['r_middle.001.L'] = bone.name
-    bone = arm.edit_bones.new('r_ring.001.L')
-    bone.head[:] = 0.0376, 0.1372, 0.0117
-    bone.tail[:] = 0.0389, 0.1311, 0.0092
-    bone.roll = -1.0029
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_palm.003.L']]
-    bones['r_ring.001.L'] = bone.name
-    bone = arm.edit_bones.new('r_pinky.001.L')
-    bone.head[:] = 0.0466, 0.1444, 0.0083
-    bone.tail[:] = 0.0476, 0.1412, 0.0074
-    bone.roll = -1.7551
-    bone.use_connect = False
-    bone.parent = arm.edit_bones[bones['r_palm.004.L']]
-    bones['r_pinky.001.L'] = bone.name
-    bone = arm.edit_bones.new('r_index.002.L')
-    bone.head[:] = 0.0217, 0.1325, 0.0070
-    bone.tail[:] = 0.0221, 0.1271, 0.0038
-    bone.roll = -0.2465
-    bone.use_connect = True
-    bone.parent = arm.edit_bones[bones['r_index.001.L']]
-    bones['r_index.002.L'] = bone.name
-    bone = arm.edit_bones.new('r_middle.002.L')
-    bone.head[:] = 0.0324, 0.1297, 0.0092
-    bone.tail[:] = 0.0343, 0.1210, 0.0039
-    bone.roll = -0.7479
-    bone.use_connect = True
-    bone.parent = arm.edit_bones[bones['r_middle.001.L']]
-    bones['r_middle.002.L'] = bone.name
-    bone = arm.edit_bones.new('r_ring.002.L')
-    bone.head[:] = 0.0389, 0.1311, 0.0092
-    bone.tail[:] = 0.0407, 0.1229, 0.0042
-    bone.roll = -0.7479
-    bone.use_connect = True
-    bone.parent = arm.edit_bones[bones['r_ring.001.L']]
-    bones['r_ring.002.L'] = bone.name
-    bone = arm.edit_bones.new('r_pinky.002.L')
-    bone.head[:] = 0.0476, 0.1412, 0.0074
-    bone.tail[:] = 0.0494, 0.1351, 0.0032
-    bone.roll = -0.8965
-    bone.use_connect = True
-    bone.parent = arm.edit_bones[bones['r_pinky.001.L']]
-    bones['r_pinky.002.L'] = bone.name
-
-    bpy.ops.object.mode_set(mode='OBJECT')
+    bones = create_paw_sample(obj)
     pbone = obj.pose.bones[bones['thigh.L']]
-    pbone.rigify_type = 'limbs.paw'
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    try:
-        pbone.rigify_parameters.limb_type = "paw"
-    except AttributeError:
-        pass
-    try:
-        pbone.rigify_parameters.fk_layers = [False, False, False, False, False, False, False, False, False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False]
-    except AttributeError:
-        pass
-    try:
-        pbone.rigify_parameters.tweak_layers = [False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False]
-    except AttributeError:
-        pass
-    try:
-        pbone.rigify_parameters.segments = 2
-    except AttributeError:
-        pass
-    pbone = obj.pose.bones[bones['shin.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['foot.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_toe.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_palm.001.L']]
-    pbone.rigify_type = 'limbs.super_palm'
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_palm.002.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_palm.003.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_palm.004.L']]
-    pbone.rigify_type = 'limbs.super_palm'
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_index.001.L']]
-    pbone.rigify_type = 'limbs.simple_tentacle'
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    try:
-        pbone.rigify_parameters.tweak_layers = [False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False]
-    except AttributeError:
-        pass
-    pbone = obj.pose.bones[bones['r_middle.001.L']]
-    pbone.rigify_type = 'limbs.simple_tentacle'
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    try:
-        pbone.rigify_parameters.tweak_layers = [False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False]
-    except AttributeError:
-        pass
-    pbone = obj.pose.bones[bones['r_ring.001.L']]
-    pbone.rigify_type = 'limbs.simple_tentacle'
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    try:
-        pbone.rigify_parameters.tweak_layers = [False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False]
-    except AttributeError:
-        pass
-    pbone = obj.pose.bones[bones['r_pinky.001.L']]
-    pbone.rigify_type = 'limbs.simple_tentacle'
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    try:
-        pbone.rigify_parameters.tweak_layers = [False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False]
-    except AttributeError:
-        pass
-    pbone = obj.pose.bones[bones['r_index.002.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_middle.002.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_ring.002.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-    pbone = obj.pose.bones[bones['r_pinky.002.L']]
-    pbone.rigify_type = ''
-    pbone.lock_location = (False, False, False)
-    pbone.lock_rotation = (False, False, False)
-    pbone.lock_rotation_w = False
-    pbone.lock_scale = (False, False, False)
-    pbone.rotation_mode = 'QUATERNION'
-
-    bpy.ops.object.mode_set(mode='EDIT')
-    for bone in arm.edit_bones:
-        bone.select = False
-        bone.select_head = False
-        bone.select_tail = False
-    for b in bones:
-        bone = arm.edit_bones[bones[b]]
-        bone.select = True
-        bone.select_head = True
-        bone.select_tail = True
-        arm.edit_bones.active = bone
-
-    for eb in arm.edit_bones:
-        if ('thigh' in eb.name) or ('shin' in eb.name) or ('foot' in eb.name) or ('toe' in eb.name):
-            eb.layers = (False, False, False, False, False, False, False, False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False)
-        else:
-            eb.layers = (False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False)
-    arm.layers = (False, False, False, False, False, True, False, False, False, False, False, False, False, True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False)
-
-
-if __name__ == "__main__":
-    create_sample(bpy.context.active_object)
+    pbone.rigify_type = 'limbs.rear_paw'
+    return bones