How to Properly Rig and Use Any Character

This essential guide solves one of the most common issues Desktop Engine users face: importing 3D characters with broken or incompatible bone structures. While Desktop Engine supports VRM, GLB, GLTF, and FBX formats, many characters from various sources have improperly named bones that don't match Desktop Engine's humanoid requirements.

If you've tried to import characters only to find that Desktop Engine's auto-find feature fails to map critical bones correctly (missing arms, spine, or other essential bones), this guide provides a proven solution using Mixamo's free auto-rigging service.
Instead of manually fixing bone mappings (which requires advanced rigging knowledge), this workflow converts your problematic character through Mixamo's automatic rigging system and brings it back as a properly structured FBX file that Desktop Engine's auto-find feature can handle perfectly.

Perfect for users importing characters from VRChat, VRoid Hub, asset stores, or custom models that refuse to work with Desktop Engine's built-in rigging system. The process takes about 5-10 minutes and requires no technical rigging experience - Mixamo handles all the complex bone mapping automatically.

By following this guide, you'll transform any problematic character into a fully functional Desktop Engine avatar that works seamlessly with all animation features, physics, and interactive systems.

Overview and Problem Identification

Understanding the Problem

Some character bones are not properly named or are not suitable for humanoids when imported into Desktop Engine. This guide will fix these incorrectly mapped humanoid bone character issues.


Common symptoms include:

• Auto Find button fails to map all required bones
  
• Missing arm, leg, or spine bone assignments
  
• Character appears in T-pose and won't animate
  
• Error messages about missing humanoid bones

What causes these issues:

• Incorrectly named bone structures from different software
  
• Non-standard bone hierarchies
  
• Characters designed for non-humanoid rigs
  
• Export/import format inconsistencies

The screenshot shows Avatar Settings with 2 errors and 12 warnings (indicated by the red error icon), demonstrating the bone mapping problems that this guide will solve.

Initial Setup and Character Orientation

First Import Steps

When you first import your character into Desktop Engine, you may notice orientation or mapping issues.

Fixing Character Orientation

If your character is not facing you upon first import, click to rotate the armature root to correct the orientation.

Adjusting Transform Properties

You can then adjust the transform properties in the Model Settings panel:

• Position: X, Y, Z coordinates
  
• Rotation: Adjust character facing direction
  
• Scale: Resize the character as needed

Note: The image shows the "Rotate Armature Root" button highlighted with a red arrow, which helps fix character orientation issues. The Model Settings panel below shows the Position, Rotation, and Scale controls.

Avatar Configuration and Bone Mapping

Identifying Bone Mapping Issues

Navigate to the Avatar section and click "Auto Find". You may notice missing or incorrectly mapped bones.

Searching for Correct Bones

When Auto Find fails, you can manually search for bones by clicking on any bone field in the Avatar tab. This opens a searchable dropdown where you can:

• Browse available bone names in your character
  
• Search for specific bones by typing
  
• See problematic naming like "L_arm_020" and "R_arm_042"

Critical vs Optional Bones

Understanding which bones are essential:

Critical bones (must be mapped):

• Spine/Hip bones
  
• Left and Right Arms (Upper arm, Lower arm)
  
• Left and Right Legs (Upper leg, Lower leg)
  
• Head bone

Optional bones (can be missing):

• Jaw bone
  
• Individual finger bones
  
• Toe bones
  
• Eye bones

The screenshot shows the bone search dropdown displaying non-standard bone names that don't follow humanoid naming conventions, making manual mapping difficult.

If critical bones cannot be found or mapped manually, proceed to the Mixamo solution.

Converting Files for Mixamo

Preparing for Mixamo Auto-Rigging

Mixamo is a free Adobe service that provides automatic character rigging. However, it has specific format requirements.

Supported Formats

Mixamo accepts: FBX, OBJ
Mixamo does NOT accept: GLB, GLTF, VRM

Conversion Options

If your character is in an unsupported format:

Online converters:

• Search "GLB to FBX converter" or "GLB to OBJ converter" on Google
  
• Many free online tools available
  
• Upload your file and download converted version

Software export:

• If you have access to Blender, 3DS Max, or similar: Export directly as FBX
  
• Use FBX 2014/2015 format for best compatibility

Recommended settings for export:

• Include animations: No (we want clean base mesh)
  
• Apply modifiers: Yes
  
• Include armature: Yes

Important note: Desktop Engine supports VRM, GLB, GLTF, and FBX formats, but Mixamo only works with FBX and OBJ. This conversion step is temporary - you'll get your character back as FBX which Desktop Engine fully supports.

Mixamo Auto-Rigging Process

Using Mixamo's Free Auto-Rigging

https://www.mixamo.com and create a free Adobe account if needed.

Upload Process

1. Click "Upload Character"
   
2. Select your converted FBX or OBJ file
   
3. Wait for upload to complete

Auto-Rigging Setup

1. Mixamo will automatically detect your character
   
2. Position the bone markers if they're not perfectly aligned:
   
   • Chin marker on the chin
     
   • Wrist markers on both wrists
     
   • Elbow markers on both elbows
     
   • Knee markers on both knees
     
   • Groin marker at the hip center
     
3. Click "Next" to process the auto-rig

Verification

Once processing is complete, your character should be properly rigged. You can test this by applying a simple animation to verify all bones work correctly.

The screenshot shows Mixamo's auto-rigger interface with bone placement markers positioned on the character. The colored circles (chin, wrists, elbows, knees, groin) help Mixamo understand your character's anatomy.

Downloading from Mixamo

Downloading the Rigged Character

Download Settings

In Mixamo, set these download parameters:

• Format: FBX ASCII (.fbx)
  
• Pose: T-pose
  
• Skin: With Skin
  
• Keyframe Reduction: Uniform

Important: Choose FBX ASCII format as Desktop Engine fully supports this format.

Character Verification

Your character should now be successfully rigged in Mixamo's viewer. You can see it properly positioned and ready for download.

Download Process

1. Click the "Download" button
   
2. Wait for the file to process and download
   
3. Save the FBX file to your computer

The screenshot shows Mixamo's download settings panel where you can configure the export format and pose options.

Re-importing to Desktop Engine

Re-importing Process

1. Import your newly downloaded FBX file into Desktop Engine
   
2. Navigate to Model Settings
   
3. Adjust scale if needed (commonly 100.0 works well for Mixamo characters)
   
4. Go to Avatar Settings
   
5. Click "Auto Find"

Success Verification

You should now see:

• 0 errors, 3 warnings, 52 successful bone mappings (green checkmarks)
  
• All critical bones properly mapped with mixamo naming (mixamorig:Hips, mixamorig:Spine, etc.)
  
• Optional bones like Jaw, LeftEye, RightEye automatically detected as "Not in Model" (yellow warning icons)
  
• Character appears in proper T-pose position

Normal Behavior Notes

Character Position:

• It's completely normal if your character appears sunken or at the bottom of the viewport
  
• This will automatically correct itself when animations are applied
  
• The character positioning will look natural once Desktop Engine's animation system takes over

Warning Icons:

• Yellow warning icons for optional bones (Jaw, Eyes) are normal
  
• Desktop Engine automatically detects these as missing but non-critical
  
• These warnings don't affect functionality

The screenshot shows 52 successful bone mappings with proper mixamo naming. Notice the yellow warnings for optional bones like "Jaw", "LeftEye", "RightEye" - these are automatically detected by the system and are completely normal.

Adding Animations

Setting Up Character Animations

With your character properly rigged, you can now add animations.

Animation Options

Desktop Engine animations:

• Navigate to the Animation tab
  
• Browse available built-in animations (idle01_breathing, idle02_LookLeftAndRight, etc.)
  
• Select and apply animations to your character
  
• You can select multiple animations at once (as shown: 9 selected)

Mixamo animations (optional):

• Return to Mixamo with your rigged character
  
• Browse and download additional animations
  
• Import as Generic animation type in Desktop Engine
  
• Use these instead of or alongside official animations

Animation Settings

• Set animations to loop if desired
  
• Adjust animation speed/timing
  
• Configure blend settings between different animations
  
• Use the "Selected Animation Clips" counter to track your selections

The screenshot shows the Animation List with multiple idle animations selected. Your character is now fully functional and will animate naturally instead of staying in T-pose.

Your character should now be fully functional with Desktop Engine's animation system!

Troubleshooting and Tips

Common Issues and Solutions

Scale Problems

Issue: Character appears too large or too small
Solution: Adjust scale in Model Settings (try values like 100, 1.0, 0.01, or 10)

Character Position

Issue: Character appears stuck at bottom of screen
Solution: This is normal for Mixamo-rigged characters; will correct when animations are applied

Missing Textures

Issue: Character appears white/untextured after Mixamo
Solution: Mixamo only processes geometry; you may need to reapply original textures

Animation Issues

Issue: Animations don't play correctly
Solution: Ensure you selected "Generic" animation type for Mixamo animations

Best Practices

• Always use FBX ASCII format when downloading from Mixamo
  
• Keep original character files as backup before processing
  
• Test with simple animations first before complex setups
  
• Remember that optional bones like jaw won't break core functionality
  
• The 52 successful bone mappings indicate a properly rigged character

When This Method Won't Work

• Characters with highly unusual proportions (non-humanoid)
  
• Characters missing critical geometry (arms, legs, torso)
  
• Heavily stylized characters that confuse auto-detection

For these rare cases, manual bone assignment or professional rigging software may be required.