FAQ

General Information

So, it’s a magic one click rigging solution?

It’s not! It includes many tools to automate and speed up the rig, but the rigging artist’s hand is still required to adjust the bones positions, vertex weights…

Can I sell characters rigged with Auto-Rig Pro?

Of course you can. Just include the “rig_tools” addon in the download package, to include the IK-FK snap and other features to animate the character.

What can I rig with it?

It’s meant to rig any stylized or realistic character, based on bipeds/multi-peds bone structure: humans, cats, dogs, centaurs, spiders, birds… Here are the available limbs:

  • Spine

  • Arm, with optional fingers

  • Wings with feathers, based on arms

  • Leg, with optional toes

  • Head, with neck

  • Ears

  • Tail

  • Chain: Spline IK

  • Chain: Bendy Bones

On top of that, it’s of course possible to add new bones manually for specific needs (hair, clothes, props…).

The following character presets are also included:

  • Human

  • Dog

  • Horse

  • Bird

How does the auto-detection (Smart) work, what limitations?

It works for biped characters only, the model must be in T-Pose or A-Pose. It detects the feet, legs, spine, arms, fingers position and optionally the facial bones. Depending on the character, some manual correction may be required. The algortihm finds the vertices in the markers neighbourhood, compute the volume, position of each part, then analyze the datas to place the bone according to the standard biped proportions. If the model is too special and does not meet these requirement, you can skip the auto-detection feature and simply place the reference bone manually.

Are asymmetrical models supported?

Asymmetrical models are supported by both the smart feature and manual bones edition. By turning off Mirror when placing the markers and X-Mirror Axis when editing the reference bones:

_images/xmirror_28.jpg _images/smart_mirror_28.jpg

Does it include bendy bones?

They’re currently used to handle the neck twist deformation, and for the leg and arms secondary deformers in option, since they’re not exportable to game engines. To export the secondary bones to Fbx, it’s best to stick to the “Twist” or “Additive” mode.

Is it possible to add new, custom bones?

Sure, new bones can be added after generating the final rig (Match to Rig). No reference bones can be created for the custom bones, they will remain in the final rig. However new bones are not exported by default, to export them see Custom bones

Is it possible to delete bones?

If disabling a full limb doesn’t give you enough precision to disable a specific bone, hide the bones you don’t need (H key) but don’t delete them, it would lead to the addon malfunction. Then just delete the vertex groups of the hidden bones to make them ineffective.


Issues

The addon doesn’t install

First, make sure you downloaded and installed the correct addon version: for Blender 2.79, Auto-Rig Pro 3.40 must be installed, while for Blender 2.8x, Auto-Rig Pro 3.47 and above must be installed. See Installing the Addons

If it still doesn’t work, you may have installed previously the whole downloaded zip file, instead of the addons files located in the addons folder, in this case it’s necessary to remove manually this invalid installation:

  • Close Blender

  • Navigate to the Blender addons folder. On Windows it’s generally located here: C:\Users\YOUR_ACCOUNT_NAME\AppData\Roaming\Blender Foundation\Blender\2.81\scripts\addons

  • Delete any “auto_rig_pro” folder or file that you can see.

  • Also delete any “addons” folder if there are any, which are nested inside the main “addons” folder this way: …2.81/scripts/addons/addons/

  • Start Blender and install the addons (Installing the Addons)


Rig: IK bones roll can’t be adjusted

The IK bones roll is calculated internally when clicking Match to Rig, based on the bones alignment. This is necessary for correct IK-FK snapping and pole calculation. The roll can be adjusted by shifting the bones positions to modify the alignment, see IK Chains.


Skin: Binding freezes

If Blender freezes when binding, it means there are either too many polygons, or the mesh is made of hundred of separate pieces (for example multiple hair meshes) while the Split Parts option is enabled. Thus, it’s very long to bind because each separate piece is split into a new object and skinned internally. To solve it:

  • Use the Voxelize option

  • Or use the Optimize High Res option and set the Polycount Threshold value lower than the amount of faces of the object, i.e. 50.000

  • Alternatively, use the Voxel Heat Diffuse Skinning addon: Voxel Skinning


Skin: Binding does not work or partially work, help!

Unfortunately, there are a few cases preventing binding to work due to invalid mesh topology. This is a current limitation of the Blender automatic weight solver, that Auto-Rig Pro is using as well. Here are instructions to fix it:

  • Enable Split Parts: Meshes made of multiple non-connected pieces (clothes, teeth, eyes…) may skin poorly/not at all if Split Parts is not enabled.

  • Unit scale: If the mesh is very high poly, it may not work because of the very short distance between vertices. Scale up the character and armature (S key, then type numpad 10 to scale ten time bigger), bind the mesh, then scale it down (S key, type numpad 0.1) to reset to the inital scale.

  • Invalid topology: First perform a remove double to delete multiple unnecessary vertices at the same location: select all vertices, W key > Remove double. Also make sure the mesh has no serious deficient topology by pressing Shift-Ctrl-Alt-M to select the non-manifold vertices. If you can see a lot of vertices selected all around the mesh (excluding boundaries), the mesh topology is not good enough: there may be edges connected to more than 2 faces, and other topology issues that needs fixes.

  • The mesh contains custom normals: Imported files such as OBJ and FBX format may contain complex/dirty normal datas that the binding solver does not appreciate. Delete them, select all vertices, press Shift-N to recalculate correct normals data.

_images/custom_normal_28.jpg
  • Coordinates are not initialized: Make sure you initialized the mesh rotation and position by pressing Ctrl-A

  • Others : If it still doesn’t work, as weird as it may sound, the mesh is likely subject to an unindentified internal Blender bug that can be strangely fixed by adding a subsurf modifier. Add the subsurf modifier (level 1 is fastest), bind the mesh then delete the modifier.


Skin: Binding works, but it’s not smooth

When using very high poly meshes (~80.000 faces) the Blender automatic weight solver may become slightly buggy on the edges… A simple way to fix this is switching to Weight Paint mode, and add a little negative level offset to the weight groups. And if more accuracy is needed, just paint over the automatic weights.

_images/weight_level_fix_28.gif

Remap: the feet stay in place

By default, building the bones list will try to match the source feet bones to the target FK feet bones. However, the feet are by default in IK mode. Just switch them to FK if you use the FK remapping, or IK if you use the IK remapping, see: Arms and Legs


Smart feature

The markers are invisible?

Make sure the scene units are set to 1.0 scale. You’ll be able to change it later (e.g. Unreal export) but the smart feature only works with 1.0 scale units.


Game Engine Export

Animations don’t export properly

See the Animations Export doc.

Wrong fingers rotation in Unreal

When importing the rig in Unreal as the Unreal Mannequin rig, it will perfectly match current animations only if the bones rotation are fully identical to the Mannequin rig. The automatic A-Pose in Auto-Rig Pro doesn’t take into account the bones roll/twist rotation value, which can lead to differences with the Mannequin rig.

It’s especially important for fingers. If you need perfect match, it’s necessary to correct the finger rotation so that it matches exactly the Mannequin fingers rotation, then Apply Pose as Rest Pose and Match to Rig. Here is the Mannequin armature blend file, you can append it in Blender for comparison.

Note that the fingers X axis is pointing up, while the Z axis is pointing up for Auto-Rig Pro fingers, this 90 rotation difference should be kept when rotating bones.

_images/mannequin_fingers.jpg

When exporting with x100 Units, the legs are broken?

_images/ue_units_bug.jpg

Due to the an imprecision of the IK stretch calculation, Blender does not handle well big models, whose scale are multiplied by 100 when switching to Unreal Engine units. Unfortunately, after many trials, there’s nothing I can do on my side (addon code) to prevent it. The bug has been reported and hopefully and will be fixed someday. As a workaround, before clicking UE Units just make sure to scale the armature and mesh objects together so that they’re not bigger than the standard grid floor, in Blender units.

_images/ue_units_bug_grid.jpg

Misc

Is it possible to mirror a full animation? Flipping the right controllers keyframes to the left?

Yes! Blender supports that natively.

_images/mirror_keyframes_28.jpg