Auto-Rig

Note

This doc is made for Blender 2.8. For Blender 2.79 users, the old doc can be downloaded here.

Overview


Setup

Setting up the model

  • The character model must be in the center of the world (0,0,0)

  • It has to face the -Y global axis, it means the face and feet must point toward the front view (numpad 1). If it’s not the case, just turn the object by 90° steps until it faces the front view (R key, Z key, type 90 numpad keys). You can also use the Turn buttons of the Smart tools to rotate the model so that it faces the camera (read below).

_images/character_setup.jpg
  • Initialize its transforms: Ctrl-A > Position, Ctrl-A > Rotation & Scale


Add the armature

  • Press N key to enable the properties panel in the 3d view right area.

  • Look for the ARP tab

_images/rig_add_armature5.png
  • Press the Add Armature button in the Rig tab.

_images/add_armature28.png
  • Choose a rig preset . This part of the documentation covers the Human rig only, but the same principles apply to the other types. The Empty preset is used to build a rig from scratch, it does not contain any limbs by default. Arms, legs, spine… can be added by clicking the Add Limbs button.

Note

One character per file is supported when rigging, only one armature at a time can be added for safety reasons. However, of course, multiple characters can be imported in the same file once they’re rigged for animation or other purposes, see Appending - Linking in a scene

Important

Do not delete any objects or bones linked to the armature, even if they’re invisible, such as cs_grp and its children, cam_ui, rig_add, etc…). Do not rename Auto-Rig Pro bones, it would break the rig.


Smart


The Smart feature is useful to quickly place the reference bones within a few clicks. It only works with biped character (may be extended to quadrupeds later). It has been designed to cover several cases, however there are few guidelines to follow:

  • Only one character per blend file is supported. The Smart tool won’t work if there are any other existing rigs in the file.

  • The character can be in T-Pose or A-Pose. For the fingers detection, there must be enough spaces between fingers. The palm must face the floor, if the hand is too much twisted forward or backward, the fingers detection will fail.

If your character’s fingers don’t meet these requirements, you can choose Skip Fingers above the Go button (read below). If the whole character it not a biped, skip this part and go straight to the next chapter to manually place the reference bones.

Limitations

Depending on the character proportions, manual corrections after the detection may be required. Also fingers may not detect properly if:

  • There is not enough space between them

  • They are too curled

  • There are too many complicated shapes around the hand, such as big bracelets, props, for example.

  • Too simple/low-poly model, or “weird” shapes


How to use

  • Facial: if you wish to setup the facial markers (optional), first make sure the eyeballs are a separate object

  • Show the ARP addon interface: press N key to enable the properties panel in the 3d view right area, look for the ARP tab, then Auto-Rig Pro: Smart menu.

  • Select all of the body objects. Avoid selecting props, clothes objects if they’re not necessary to define the character body.

  • Click Get Selected Objects in the Auto-rig Pro : Smart panel

_images/auto_rig_pro_smart_28.jpg

The camera will frame the character in front view.

  • If the character doesn’t face the camera, you can use the Turn buttons to rotate by 90° steps

_images/smart_tab_add2_28.jpg

Body

  • If the character is not symmetrical, uncheck Mirror. If enabled, the left markers/bones are mirrored to the right (right from the character’s perspective, screen-left)

  • Click the Add Neck button. A new circle shaped marker is added, move the mouse cursor to position it at the root of the neck.

  • No need to rotate the view while doing this, keeping the front view will be fine. The solver will automatically find the depth

  • Click the next button Add Chin, position it nearby the chin, and do the same for the other markers

  • Press the Go! Button

_images/smart3_28.gif

Set the number of fingers of the character:

_images/fingers_count_28.jpg

Facial

Optionally you can setup the facial markers (if you wish to rig the facial):


  • Push the Facial Setup button.

  • Position the markers vertices to match your character face proportions:

_images/facial_markers.jpg
  • Enter the eyeball object name in the dedicated input field

_images/smart_eyes.jpg
  • Press the Go! button

After a few seconds, the references bones should be properly positionned on the model. Note that this may require additional manual tweaking to get a more accurate placement.

The fingers detection should run fine with most of the characters, however it may fail sometime. In this case, the first thing to try is to move a little the wrist marker (you can click Recover Last Session to restore the previous markers positions). Then reduce or increase the Voxel Precision value, and then try to increase the Finger Thickness. If it still does not work, there’s something special in the hands design that prevents the detection to work. Feel free to send your character for inspection (check Bug Report - Support), if the issue can be fixed I’ll let you know, if not, place the fingers manually: see the chapter Positionning the Reference Bones. The markers can be restored, to try different positions, by clicking Restore Last Session after Get Selected Objects.


Rig Definition

Limbs Setup

Now it’s time to configure and define the skeleton.

  • Select the armature object

  • If you don’t use Auto-rig Pro : Smart, first scale the armature in object mode so that it globally fits the character height

  • Show the ARP interface: press N key to display the properties panel at the right of the viewport, look for the ARP tab

  • Auto Rig Pro > Rig tab > click Edit Reference Bones

Note

Reference bones can be edited anytime after the rig completion by simply clicking Edit Reference Bones again

_images/rig_def_v8.jpg
  • Limbs can be added one by one using the Add Limb button.


Biped - Multiped

For quadruped characters (dog, cat, horse…) it’s necessary to switch to Multi-Ped type instead of the default Biped. As Biped, the spine controller shapes are oriented vertically. As Multi-Ped, their orientation is free, since a quadruped/multi-ped stands with his “hands” on the ground. Here is an example to position bones for a quadrupedal creature.

_images/biped_multiped.jpg

Limb Options

Limbs have various options to fit… various needs! To access options of a limb, select a bone from it and click Limb Options. For example, select an arm bone and click Limb Options to enable or disable the fingers, by ticking/unticking the checkboxes. To disable, add or duplicate a specific limb, see chapter Duplicate - Disable Limbs

_images/limb_options_arm.jpg

Head Options

_images/head_limb.jpg _images/head_options.jpg

Facial

Add facial controllers

Soft Lips

Enable lips elasticity effect for more natural deformations

_images/soft_lips.gif

Soft Lips: Visual Only

The soft lips effect will be only visual, it won’t deform except the lips corner. Useful when using shape keys as lips deformations.

Eye Targets Distance

Adjust the eye target distance from the head


Neck Options

_images/neck_limb.jpg _images/neck_options.jpg

Count

Number of neck bones

Twist Bones

Add neck twist bones

Bendy Bones

Use multiple bendy bones segments to smoothen the neck twist deformation (warning, not export compliant, for internal Blender projects only)


Spine Options

_images/spine_limb.jpg

Count

Number of spine bones, from 1 to 32. To export to Unreal Engine as a humanoid rig, 4 spine bones are required.

Bottom

Add bottom (buttock) bones


Arms Options

_images/arm_limb.jpg

Twist Bones

Number of twist bones.

  • If the rig is not exported to game engines, 1 is enough since the Blender armature modifier handles dual quaternions skinning (Preserve Volume).

  • When exporting to game engines, multiple twist bones are recommended for best deformations (3-4 or more) since Preserve Volume is not supported by game engines. Multiple twist bones totally solve the candy paper wrap issue when twisting hands/feet. Above one twist bone, below 4 twist bones in Unreal Engine:

_images/multiple_twist.gif _images/arm_twist.jpg
  • However, 1 twist bone is required to match the Unity’s humanoid rig. Unreal’s humanoid rig support multiple twist bones.

Rotate Fingers from Scale

Fingers phalanges can rotate when scaling the first one. Set the Rot From Scale property above the fingers checkboxes. Set it to Disable to disable this feature.

_images/new_finger_rot.gif

Fingers Shapes

Default shape for the fingers controllers: boxes, circles

Fingers

Add fingers (thumb, index, middle, ring, pinky)

IK Pole Distance

Adjust the IK pole controller distance from the elbow

Fingers IK-FK

If Fingers IK-FK is enabled, IK controllers will be added to each fingers, with IK-FK switch and snap settings, and all tools dedicated to manipulate IK fingers.

_images/fingers_ik.gif
  • IK Parent: Parent bone of the IK target controllers

  • Pole Parent: Parent bone of the IK pole controllers

  • IK Root Shape: Custom shape used to draw the IK Root target controller, located at the root of the third phalange

  • IK Tip Shape: Custom shape used to draw the IK Tip target controller, located at the tip of the third phalange

  • Pole Shape: Custom shape used to draw the IK Pole controller, located above the second phalange bone

  • IK Pole Distance: Distance from the second phalange to the IK pole

For fingers IK to work properly, it’s best to make sure that finger bones (reference bones) are slightly curved upward. Otherwise, the IK direction will be inverted and fingers can fold in the wrong direction:

_images/fingers_direction.jpg

Correct fingers curvature

_images/fingers_ik_correct.gif

_images/fingers_wrong_direction.jpg

Wrong fingers curvature that leads fingers to fold in the wrong direction

_images/fingers_ik_inverted.gif

Wings

Add feathers bones to the arm, forearm and hand bone with various settings.

_images/wings_tab.jpg _images/wings_demo2.gif
  • Arm Feathers: amount of feathers for the arm bone

  • Forearm Feathers: amount of feathers for the forearm bone

  • Hand Feathers: amount of feathers for the hand bone

  • Feather Subdivisions: amount of bones per feathers, to curve its shape (example below with 4 subdivisions)

_images/feather_curved.jpg
  • Feather Layers: Amount of layers/rows of feathers, on top of each other (example below with 3 layers)

_images/feathers_layer.jpg
  • Update Existing Feathers Transforms: update existing reference feather bones transforms when clicking the OK button (grid align). If disabled, existing feathers won’t move. Useful to add new feathers while preserving existing ones.

  • Parent Feathers Layers: parent feathers layers. If disabled, feather layers move independently.

  • Add Wings Fold Controller: add a controller to fold the arms and feathers by scaling it. Requires an action containing rig_wings_fold in its name, rest pose at frame 0, folded pose at frame

Note

  • Create a new action named rig_wings_fold

  • Keyframe arm and feather bones controllers in reset pose (rest pose) at frame 0, folded pose at frame 10

  • Click Edit Reference Bones

  • Select an arm bone and click Limb Options

  • Enable Add Wings Fold Controller

  • Click OK

  • Click Match to Rig

  • Unlink the rig_wings_fold from the rig

_images/wings_fold.gif

Naming: the feather bones are named this way:

bone_type + ‘feather’ + feather number + layer number + subdivision number + side

For example: c_hand_feather_02_03_02.l


Legs Options

_images/leg_limb.jpg _images/leg_options.jpg

Twist Bones

Number of twist bones.

  • If the rig is not exported to game engines, 1 is enough since the Blender armature modifier handles dual quaternions skinning (Preserve Volume).

  • When exporting to game engines, multiple twist bones are recommended for best deformations (3-4 or more) since Preserve Volume is not supported by game engines. Multiple twist bones totally solve the candy paper wrap issue when twisting hands/feet. Above one twist bone, below 4 twist bones in Unreal Engine:

  • However, 1 twist bone is required to match the Unity’s humanoid rig. Unreal’s humanoid rig support multiple twist bones.

3 Bones Leg

Add an extra bone at the root of the chain, useful for certain creatures such as T-Rex, quadrupeds. To use full 3 bones IK instead of two when posing the character, see (Legs 3 Bones)

Toes

Add toes (thumb, index, middle, ring, pinky)

Toes Pivot Controller

Add a controller to rotate the whole foot from the toes

_images/toes_pivot.gif

IK Pole Distance

Adjust the IK pole controller distance from the knee.


Tail Options

_images/tail_limb.jpg

Count

Set the number of tail bones

Master Controller at Root

Set the tail master controller, which rotates all tail bones at once, at the root position of the tail.


Ear Options

Count

Set the number of ear bones


Spline IK options

_images/spline_ik_limb.jpg _images/spline_ik_options.jpg

IK Splines are useful bone chains to rig ropes, tentacles… It can also be used as a replacement for the default FK spine. It’s recommended to keep 1 spine bone though, to keep the c_root_master and c_root controller, and parent the root bone of the Spline IK to it.

IK Spline Count

Number of bones for the IK spline bones chain

Bendy Bones Count

Number of bendy-bones per bone, for a smoother result.

Curve Smoothness

Increase or decrease the extra smoothing of the curve shape. Decreasing it is useful if spline bones have different locations between rest/pose position due to the curve extra smoothing.

Side

Define the side (middle .x, left .l, right .r) of the chain, by renaming bones with the chosen suffix.

Deform

Enable or disable weight deformation of the spline IK bones. Disabling it may be useful when creating more bones (by hand) over the existing ones, to set new bones as the deforming ones instead of the base spline IK bones.

Update Transforms

Change the existing spline reference bones position when clicking OK (grid align). Disable it to preserve their position. If the spline count is changed, enabled automatically.

End Controller Parent

To define the parent of the last bone of the chain. By default set to the tip controller, however it can produces interesting effects for ropes when parenting to the root.

Advanced Mode

The Advanced mode enables more options to fine tweaks the curve shape with master, inter, and individual controllers.

_images/spline_ik_advanced.jpg _images/spline_ik_advanced_demo.gif

Controllers Frequency

The frequence defining the master controllers spacing along the bones chain. For example, setting to 2 will add a master controller every 2 bones.

Interpolation

Interpolation type for the inter controllers, between two master controllers. Linear produces straight lines, while Smooth leads to curved lines.

_images/spline_ik_linear.gif _images/spline_ik_smooth.gif

c_spline_master parent

Parent bone of the c_spline_master bone. Setting it to None allow free parent, by manually setting it.

c_spline_master tip parent

Parent bone of the last c_spline_master bone (at the tip of the chain). Setting it to None allow free parent, by manually setting it.

c_spline_tip parent

Parent bone of the c_spline_tip parent. Setting it to None allow free parent, by manually setting it.

Note

IK Splines are exportable, but bone scale/stretch and bendy-bones are not supported. Using IK Splines as spine bones it not yet supported in Humanoid export mode.

_images/spline_ik_demo.gif _images/spline_ik_rope.gif

Bendy-Bones Options

_images/spline_ik_limb.jpg

Bendy-Bones chains are useful to rig stretchy components, hair, snakes… Each bone is subdivided into multiple segments, allowing smooth, consistent deformations.

_images/bbones_chain.gif

Note

Bendy-bones chains are not exportable to Fbx! May be supported later.

Bendy Bones Count

Amount of bones in the chain

Bendy Bones Segments

Number of bendy-bones segment per bone

Controller Scale

Scale of the controller shapes

Side

Define the side (middle .x, left .l, right .r) of the chain, by renaming bones with the chosen suffix.


Secondary Controllers

_images/secondary_bones_28_2.jpg

There are 3 deformation modes in option for the secondary bones (bones used to curve the arms, legs). To export to game engines, use Twist (best), or Additive mode. If no export is required, Additive will give good results, while Bendy Bones is best for stylized/cartoon characters.

Twist

  • Twist and secondary controllers are exportable to Fbx, recommended for best export compatibility.

  • One secondary controller per twist bone, consequently up to 6 per limb.

  • Bendy-bones control for easy adjustment of the global curve, while using real (twist) bones to deform and keeping it exportable.

  • Best control over the shapes, each twist bone can be moved and rotated separately.

_images/twist_based_arms.gif

Additive

  • Twist and secondary controllers are exportable to Fbx. However, the exported weights may be slightly different since the additive weights are “baked” onto the main weights.

  • 3-4 controllers per limb for precise shapes sculpting.

  • Additive skinning involves more bones, so more vertex groups.

Bendy Bones

  • Twist and secondary controllers are not exportable to Fbx. Must be used for internal Blender projects only.

  • Only 2 controllers per limb but very smooth control. Ideal for cartoon characters.

  • Easy skinning: only one vertex group per limb, the secondary and twist bones are computed internally by the bendy bones system.

None

  • No secondary controllers

Important

All changes are applied when clicking Match to Rig. Changing secondary controllers mode after binding requires to re-bind the meshes, otherwise some bone weights will be incorrect.


Positionning the Reference Bones

The reference bones are the guides used to align the final rig bones position and rotations. Whether your character is not supported by the Smart function (not a biped) or if you simply need to edit the reference bones position, here is how to:

  • Adjust the bones positions so that they fit the character proportions. You can follow the guidelines below for a biped rig, and see here for a multi-ped rig.

  • The foot_heel and foot_bank bones (the three little bones under the foot) should match the heel back position and the foot width. The foot_heel_ref bone direction is used to align the feet rotation on the final rig, make sure to set it properly.

_images/heel.png

IK Chains

  • In option, the IK pole direction can be drawn as a line to visualize its position in the final rig:

_images/show_ik_dir.gif
  • Remember to keep a slight angle between the arms/legs bones. It’s very important for the IK chains to work properly. They MUST NEVER be straight, otherwise the IK direction may be inverted.

_images/angle.jpg
  • IK chains roll can’t be manually adjusted. It’s calculated when clicking Match to Rig. Changing the bones alignment as shown below will change the roll. Here the arm is shown from the front view, it can be straight from this point of view, but must keep a slight angle backward (check from the top view):

_images/ik_roll.jpg

Spine

  • The root_ref bone tip should be centered at the bellybutton height, spine_01 at the bottom of the chest, spine_02 should reach the neck base.

_images/belly.jpg

Facial

  • The facial bones should be positionned as the following:

_images/facial_v2.jpg _images/facial_v3.jpg
  • The eyelids and eyes bone heads should be positionned at the eyeball center while the tail of the bones should reach the eyeglobe/eyelids mesh surface. The eye_offset_ref bone is used to align the global eyes direction, make sure to set it properly. All eyelids and eye_offset bones’head should be centered at the same position, in the middle of the eyeball.

  • The lips bones have to be very close to the geometry, positionned all around the lips.

  • The lips_roll bones have been designed to work with shape keys and drivers (read below the Skinning chapter).


Duplicate - Disable Limbs

_images/bally.png _images/spider.png
  • To duplicate a limb, select one bone from it and click Duplicate.

  • And in a similar way, to disable a limb click Disable.

_images/duplicate_28.jpg

Only the arms, legs, neck, head, facial, and ears can be duplicated. It may not be possible to duplicate individual bones: for example, the arms duplication will duplicate the arm, forearm, hands and fingers as a whole, the head duplication will duplicate the neck, head and linked facial if any as a whole. The fingers and spine bones cannot be duplicated yet.

Important

If disabling a limb is not precise enough to remove a specific bone, you should avoid deleting the bone manually. It can break the rig functions when clicking Match to Rig for example. Instead, consider hiding the bone. Read the FAQ to this end (“Is it possible to delete bones?”).


Parenting Reference Bones

Reference bones can be parented to each others, i.e. shoulder_ref can be parented to spine_02_ref so that the shoulders will be connected to the spine when clicking Match to Rig. However, parenting only works with predefined behaviors, i.e it’s not possible to parent leg_ref to arm_ref, it won’t work.

  • Only the root bone of a limb can be parented freely

  • When reference bones are parented to other reference bones, a dedicated scripted function will assign the final bone parent when clicking Match to Rig, using a default mapping.

  • It’s possible to force a bone parent by parenting a reference bone to a non-reference bone directly: i.e parenting shoulder_ref to the last bone of a 4 bones IK spline: spline_04_ref, will by default parent the shoulder to the tip controller of this IK spline, c_spline_05. To parent it to the previous controller c_spline_04, parent shoulder_ref to c_spline_04 directly.


Adding Custom Bones

Adding your own new bones (custom bones) for props, clothes, hair or anything required is fairly simple and straightforward. The only requirement is to add and link them to the deforming bones or controller bones, not reference bones. Meaning, bones located in the layer 31, or bones visible after clicking Match to Rig. See Armature Layers

Example to add a hat bone:

  • Click Match to Rig

  • Switch to Edit Mode (Tab key) and add a bone (Shift-A)

  • Parent it to the “c_head.x” bone which is the head controller, or “head.x” bone which is the deforming bone.

It won’t interfere with the scripted instructions, unless these new bones have same names as existing ones (for example do not name a new bone “c_root.x” or “c_head.x” or “head.x”, these bones are already part of the base rig).

To export to Fbx, they must be set as custom bones in order to tell the exporter to include them in the rig, see Custom bones

Limitations:

New bones must not be inserted between bones of the same limb, for example the following bones hierarchy would break the rig since a custom bone is inserted betwenn spine bones:

root
    spine01
        mycustom_spine_bone < incorrect!
            spine02
                neck...

But this works:

neck
    head
        hat

Generate The Rig

  • Click Match to Rig to generate the final rig with controllers, and all the mechanic setup.

You can go back to edition mode and make some changes anytime by clicking Edit Reference Bones.

Note

Check Init Scale to make sure the rig scale value is initialized to 1.0 (recommended)

New Auto-Rig Pro updates may sometimes change the rig, bones constraints behaviour, bones orientations, which may break previously made animations. To correct this, click Legacy and see if any options may help to preserve existing animations.

_images/retro_compat.jpg

Bone Shapes

You may want to adjust the controllers shapes. Just click the Edit Shape… button and Apply Shape once you’re done. To mirror the shape to the other side, click the little button next to Edit Shape

_images/shape_edit_28_nomove.gif

Picker Panel

Setup

The picker addon must be installed first. See Installing the Addons.

If you haven’t done it already, you might want to split the 3D viewport into two areas, one view to display the character and one view to display the picker panel. How to do this:

  • Click at the top right corner of the 3d viewport, then hold and drag it onto the left:

_images/ui_split_28.jpg
  • In the Misc tab, Add Picker will generate a new picker (there is none by default). It’s also possible to Export or Import a picker layout file.

  • Then click the Set Picker Cam, in the view where you want to display the bone picker.

_images/misc_tab_v3_28.jpg
  • You can adjust the color theme here too.

If you can see awful dotted lines, just uncheck the Relationship Lines option in the Overlays panel.

_images/horrible_lines_28.jpg

You can add a background facial picture by framing your character’s head, and clicking Capture Facial. If you want to replace this openGL screenshot by a real render, just replace the saved image file with your own file.

To change the picker layout, click Edit Layout…. You’re now free to select, move, rotate and scale the picker bone shapes, buttons, text and background picture. Once you’re done, click Apply Layout to complete.

_images/picker_image2.jpg

Remove

  • If you don’t need the picker panel, delete it with the X icon button next to Add Picker.


X-Pose Picker

X-Pose Picker is an alternative to the Auto-Rig Pro’s built-in picker panel.

If you’re used the any picker like the AnimSchool Picker for Maya for example, this is very similar and a pleasure to use. This is a separate picker window, standalone application which can be setup for any rig. Recommended!


Import/Export Rig Data

Reference bones transforms and custom shapes can be exported as a file and imported later:

_images/export_cs.jpg

Skinning

Binding

_images/binding_engines.jpg

  • Select first the character meshes objects, then the armature while holding the Shift key.

  • Click the Bind button to bind.

_images/bind.jpg

Binding Engines

  • Heat Maps: Default engine, works best with watertight meshes (closed mesh)

  • Voxelized: If meshes are not watertight (e.g. multiple layers of clothes, props, complex topology…), consider using this engine. However, this doesn’t always lead to good results: this is not a true voxel skinning implementation, but an approximated method. It’s not as foolproof as the Voxel Heat Diffuse Skinning addon, neither as fast.

  • Voxel Heat Diffuse Skinning: Extra skinning addon to bind meshes with complex topology. Use pure voxel skinning algorithm.

Note

Voxel skinning gives best results with multiple layers of clothes/props, however it’s less accurate with small parts (fingers, facial…) than other methods. It’s useful to use it combined with Exclude Selected Verts to mix voxels skinning with surface skinning (Heat Maps). For example, use Heat Maps skinning for fingers/facial and Voxelize for the rest of the body.

_images/voxelize_example2.jpg

Binding Settings

  • Split Parts (Heat Maps): This setting tries to improve heat maps skinning when meshes are separate in multiple pieces (clothes, props…)

  • Optimize High Res (Heat Maps): Speeds up binding of high poly meshes that contains more faces than the given threshold below, by internally working on lower resolutions.

  • Type (Voxelized): Voxelization type, switch this setting to another type if it doesn’t lead to good results

  • Voxel Resolution (Voxelized-Voxel Heat): The higher this value is, the more accurate and longer to perform the voxelization will be. However, the Voxelized engine may sometimes work better with lower resolutions.

  • Refine Head Weights: Improves the head skinning based on the chin position, when facial is disabled, and for bipeds only. Make sure the reference jawbone is properly positionned, and disable facial afterward.

  • Smooth Twist Weights: Improve twist bones skinning by applying a gradient decay to weights along the bones chain

  • Improve Hips Weights: Improve hips/pelvis skinning

  • Specials: Improves eyes and eyelids skinning. Set eyeball objects, one object including both left and right eyeballs or two objects for each side. Select vertices around the left eyelid, click Set Left, and same for the right eyelid. Video tutorial.

  • Exclude Selected Verts allows to prevent the selected vertices from being bound.

  • Scale Fix: Enable this setting if meshes are very small (in Blender units space) and binding doesn’t work

When binding, all vertex groups are cleared. To preserve existing vertex groups from being removed (e.g. when using vertex groups for hair generation) click their lock icon before binding:

_images/vgroup_lock.jpg

Note

Binding can take time, especially with high resolution meshes. See the Clothes chapter to skin and attach clothes to the main body mesh easily.

Important

If binding does not work, see the FAQ


Skinning: Weight Painting and Shape Keys

It’s time to carefully paint the weight vertices for each vertex group in the list. The auto-skinning can be considered as a basis, automatic weights are never perfect.

Facial rigging demo:


How to paint the weights?

To quickly select the deforming bones and check the associated vertex groups in one click, you can display only the layer 31 of the armature, wich includes the deforming bones only:

_images/last_layer_28.jpg

A quick search in Google (such as “blender weight painting tutorial”) will give you the basis of the Blender’s weight painting tools if you don’t know them, this is something I won’t elaborate more here. Basically, it’s all about browsing the vertex groups list and painting the weights. If you’re new to Blender skinning, you can check these two videos: Rig Tips 1, Rig Tips 2

For a high quality skinning, this process can take some time, don’t hesitate to test the skin accuracy by posing the character into several extreme position (arms up, arms down, arms ahead, thighs up…)

Note

The Mike Rig is a free character rigged with Auto-Rig Pro, it can be used as a reference to understand how the weights must be distributed for each bone.

Here are a few notes about some specific painting regions:

Clothes

If the body is modeled and skinned under the clothes, a good practice is to transfer the weights from the body to the clothes. This way, they will perfectly stick to the body.

  • Select the clothes objects, then the body (holding Shift, the target first, then the source), press F3 > type “Transfer Mesh Data” > choose “Vertex Groups”. In the tool shelf options (T key, bottom area) choose Nearest Face Interpolated instead of Nearest Vertex, All Layers instead of Active Layer, and you’ll find here more options to fine-tune the transfer.

_images/transfer_weights_28.jpg

Eyes

Make sure to assign the correct vertices to these bones:

  • The big circle (c_eye_offset) is meant to deform both the eyes and eyelids. It simulates the muscles stretch and compression. The eyelids and eyesballs bones have their own vertex groups though (eyelid_bot, eyelid_top, c_eye and other secondaries), so this bone should just influence the external borders, gradually reduce the influence near the eyelids.

  • The small circle (c_eye) is meant to rotate the eyeball only.

  • The sphere circle (c_eye_ref) is meant to control the reflexion disk mesh (if any), sometime used to fake the eye reflexion, easily animatable.

_images/eyes.gif

Shape Keys

As explained earlier, the lips_roll bones are supposed to be used with shape keys.

_images/lips_roll.png

Lips roll: it will be necessary to create two shapes on your head mesh: the bottom lips kissing, and the upper lips kissing.

Note you can use shape keys to make the character smile too and for eyebrows deformations (bone deform is less accurate), if you want to do so select the bones that you want to use with shape keys, and uncheck the Deform in the bone property panel.

_images/deform_checkbox_28.jpg

The addon includes a tool to quickly create the drivers between a shape and a bone.

  • Select the armature, then in the Shapekeys Driver Tools enter the bone name driving the shape key or select it and click the little picker icon.

  • Hold Shift key and select the mesh. In the shape key list, select the one to be driven

  • Back in the Auto-Rig Pro tab, select the transform parameter you want to use to drive (location, rotation, scale and the axis)

  • Click Create Driver.

_images/create_driver_28.jpg

If the shape key increases too slowly or too fast while the bone is moving:

  • Left click on the pink shape key value then multiply ‘var’ by any number using the * (asterisk/star) character, e.g to speed up 60 time faster, write:

_images/driver_multiply_28.jpg
  • The 0, 1 and Reset buttons are optional, you can use them to set a key to 0 or 1 on the curve, according to the current bone position. It’s especially useful when using multiple shape keys, such as the eyelid rotation that may involve several shapes for big eyes.

Note

You can also negate the expression to switch the bone direction: “-var”

To delete a driver:

  • Right click on the shape key value > Delete driver


Corrective Shape Keys


Sometimes, painting weights is not enough to get correct deformations. For example, rotating the forearm or calf/leg bones at extreme positions often result in poor deformations, with penetrating faces. This is where corrective shape keys shine! They allow to fix deformations by editing the mesh manually for a given rotation. However accessing the bone rotation from the transform values is only possible with FK chains. For IK-FK chains such as the arms and legs, it’s a more complex to setup. This is why Auto-Rig Pro includes a convenient tool to do this in a few clicks:

_images/correc_shape_side_side.gif
  • Pose the arm, leg, hand… or any bone controller in the position that leads to incorrect deformations

  • Enable the layer 31 to show deforming bones or click Pick Selected Bone(s) that will show an error and display the layer 31 automatically.

  • Select one or two deforming bones involved in the deformation that needs to be fixed. If 1 bone is selected (see gif below), it must be an arm or leg bone. If 2 bones are selected, can be any bones (for example the foot and leg_twist bones to correct the ankle deformation)

  • Click Pick Selected Bone(s). If the selection is not valid, an error message should pop up

_images/correc_shape_02.gif
  • A new bone is created internally, used to define the shape key driver rotation. You can click the eye button to show the bones and angle value (in radians) that will be applied to the driver.

_images/correc_shape_03.gif
  • Select the mesh object and the corrective shape key to be applied to this pose (create one if there is none yet).

  • Click Add Corrective Driver

_images/correc_shape_04.gif
  • Done! If necessary, you can use the 0 and 1 button above, to define when the shape key must start and end.

_images/correc_shape_05.gif
  • You can also use these buttons to create intermediate shape keys that will be triggered one after another as the bone rotates, for more accurate deformations. Just copy the driver (right click on the pink area > Copy) and paste it to another shape key (right click > Paste), and use the 0/1/Reset buttons to define the shape key range.

Tip

Use the Corrective Shape Key addon to easily edit your corrective shape. This allows to create corrective shapes from another object/mesh, while preserving the current mesh deformations (modifiers + shape keys). Powerful, because editing the shape keys directly on the main mesh can lead to “Crazy Space” issues, e.g. vertices moving to the right whereas you move the cursor to the left. It comes by default with Blender, just enable it from the addons list.


Hand Fist

_images/auto_fist.gif

Optionally, you can add a fist controller on the hands. This controller is meant to blend the fingers into a pre-defined fist pose. This allows a better grasp than the default “Fingers Grasp” property since that simply curls the phalanges along the X axis, wich may be inacurrate.

  • Create a new action, its name must include “rig_fist” (for example “mycharacter_rig_fist”)

  • Keyframe the fingers controllers (rotate directly the fingers controllers, the Rotation From Scale can’t be used here) this way: frame 0 = rest pose, frame 10 = fist pose. Optionally, spread the fingers and keyframe them at frame -10.

  • Select the hand controller and click the Add Hand Fist button to generate the controller. Fingers will curl into the fist pose when scaling it.

_images/hand_fist_button_28.jpg

X-Muscle System Support

_images/x-muscle.jpg

X-Muscles System is an addon for muscle simulation, bringing more depth and credibility to realistic characters. It’s very well done and easy to setup, so I thought it could be a great addition to Auto-Rig Pro. I’ve been glad to work with its developper to make both addons compliants.

When creating muscles, you can select the deforming bones by enabling the layer 31 of the armature (last bottom right):

_images/last_layer_28.jpg

Changing the Rest Pose

Optionally, the rest pose can be changed. For example, when exporting to Unreal Engine, it’s best to set the character in A-Pose.

Set Pose

This function will automatically set the character into a predefined pose.

_images/set_a_pose.gif

Apply Pose as Rest Pose

To apply the current pose as the rest pose, the Apply Pose as Rest Pose button must be clicked. Then click Match to Rig to apply the changes to the final rig.


Set Character Name

For consistency and clarity in the final scene, set the character name used for collections and rig objects. To do this, click the button Set Character Name. E.g, naming a character “matt” will rename the collections to “matt_rig”, “matt_cs”…

_images/set_char_name.jpg

Optimizing the Rig Performances

Most characters rigged with Auto-Rig Pro, except very high poly ones or with complex modifiers setup, should reach 60 fps in the Blender viewport. They don’t? Here are tips to drastically improve performances, by gaining up to 40 fps depending on the character meshes:

Cleaning Weights

Reducing the number of bones/vertex groups influencing vertices is very efficient to improve performances. 4 bones max is a good ratio to keep in mind. Some superfluous vertex groups with weight values set to 0.01 or below may be assigned to vertices, when transferring weights between meshes or smoothing weights. Blender has a one click tool to clean them up instantly!

_images/clean_weights.gif

Clearing Custom Normals and Auto-Smoothing

Custom normals and polygons auto-smoothing are performance consuming. Unless these features are absolutely necessary, it’s best to remove them from meshes for optimal performances. Imported meshes from external file format often have custom normals.

Run this script to remove these bottlenecks automatically on all meshes:

import bpy
​
def set_active_object(object_name):
    bpy.context.view_layer.objects.active = bpy.data.objects[object_name]
    bpy.data.objects[object_name].select_set(state=1)

for obj in bpy.data.objects:
    if obj.type != "MESH":
        continue
​
    try:
        set_active_object(obj.name)
    except:
        continue
​
    obj.data.use_auto_smooth = False
​
    try:
        bpy.ops.mesh.customdata_mask_clear()
    except:
        pass
​
    bpy.ops.mesh.customdata_custom_splitnormals_clear()

Playback Options

Playing back animation in all windows (3d viewport, animation editor) is more consuming than a single one. To ensure best results, in the playback options of the timeline window, disabled all but Active Editor Only:

_images/playback_options.jpg

Meshes Hiding

Sometimes we need to hide meshes (clothes, hair) to output different versions of a character in a single file. Hiding skinned meshes with the eye icon in the outliner is wrong: these meshes will be evaluated when playing the animation, even if they’re hidden. To ensure they’re excluded from the skinning evaluation, when playing the animation, hide them from a lower level using the screen icon.

_images/hide_viewport.gif

Appending - Linking in a scene

There are two methods to load a rigged character in a final file. Appending will load a static copy of the rigged character in the file, this means if you change the character geometry or armature in the rig file, the changes won’t be applied to the character in the final file. It’s just a copy. On the contrary, Linking will load a dynamic copy of the character (instance). Changes made in the rig file will automatically be applied in the final file, which is very useful!

  • First make sure your rig file only contains your character rig and meshes objects (no render camera, light….)

  • Make sure meshes objects are parented to the armature

  • By default, all rig/character objects are grouped inside the 3 collections “charactername”, “charactername_rig”, “charactername_cs”. Make sure to include any new objects added by you as well inside (new meshes, etc…).


Appending

  • In a new scene, File > Append > Select the rigged character file > Collections > Select the 3 character collections > uncheck Active Collection > click Append from Library

Linking

  • First, you may want to hide (in viewport mode) the armature object in the source file, to prevent the rig to be displayed two times once it’s linked (it may lead to overlapping glitches).

_images/hide_rig_viewport.jpg
  • In a new scene, File > Link > Select the rigged character file > Collections > Select the root character collection (“soldier” in the image above) > click “Link from Library”

  • After linking, all objects are frozen. To make the armature editable, it must be turned into a “proxy” object: press F3 > type “make proxy” and click it > type the rig object name and click it

_images/make_proxy_28.jpg
  • If the rig contains a picker: select the rig collection, and turn the “cam_ui” camera into a proxy: press F3 > type “make proxy” and click it > type “cam_ui” and click it. The newly created proxy camera is named “charactername_rig_proxy”, select it and rename it “cam_ui”, and finally parent it to the proxy armature (in object mode, Ctrl-P > Object (Keep Transforms)). In a new window (3d viewport), select a bone in pose mode and click Set Picker Cam in the Rig Main Properties tab


Conclusion

Make sure to check the other documentation chapters on the left, Rig Features, Game Engine Export and other chapters.

Feel free to get in touch for any remarks, if anythying broke with a newest Blender API update or whatever… and happy blending!

Artell