Meshy Rhino Plugin

A Rhino plugin that enables AI-powered 3D model generation from Meshy directly inside Rhinoceros 8. Generate 3D meshes from text prompts or reference images and place them into your Rhino document as mesh objects or block instances.

Features

• Text to 3D: Generate 3D models from text descriptions (two-stage preview + refine workflow, or preview-only mode)
• Image to 3D: Create 3D models from a single reference image (.jpg, .png)
• Multi-Image to 3D: Provide 1-4 images of the same object from different angles for higher-quality results
• Text to Texture: Apply new textures to existing 3D models via text prompts or reference images (retexture workflow)
• GLB Native Import (Default): Import models via Rhino's native GLB importer, preserving PBR materials and textures
• OBJ Custom Parser: Alternative import path with per-face-vertex UV splitting for correct texture seams
• Mesh Placement: Place generated meshes directly into the active Rhino document (OBJ mode)
• Block Instance: Save generated meshes as block definitions and place as instances (OBJ mode)
• Unit-Aware: Automatically converts from Meshy output (meters) to your document's unit system
• Cancellable Generation: Cancel button allows aborting any in-progress generation task
• Configurable Generation: Control topology, polycount, AI model version, model type, symmetry, PBR maps, and lighting removal
• Thumbnail Preview: Shows a thumbnail of the generated model before placement
• Persistent Defaults: Save your preferred generation options in settings -- they apply automatically on launch
• Retry Logic: Automatic retry with exponential backoff for transient network failures

Requirements

• Rhinoceros 8 (Windows)
• Meshy account with an API key (get one here)
• Visual Studio 2022 (for building from source)

Installation

Option 1: Build from Source

1. Clone this repository:

   git clone https://github.com/QROST/Meshy-Rhino.git
   

2. Open Meshy-Rhino.sln in Visual Studio 2022
3. Build the solution in Release configuration
4. In Rhino, run _PlugInManager, click Install, and select the built MeshyRhino.dll

Option 2: Download Release

1. Download MeshyRhino.zip from the Releases page
2. Extract into a folder (e.g. %APPDATA%\McNeel\Rhinoceros\8.0\Plug-ins\MeshyRhino\)
3. In Rhino, run _PlugInManager, click Install, and select MeshyRhino.dll
4. Restart Rhino

Option 3: Yak Package Manager

A manifest.yml is included for Yak packaging. Build the .yak package with:

"C:\Program Files\Rhino 8\System\Yak.exe" build

Usage

Setting Up the API Key

1. In Rhino, type Meshy3DGenerator in the command line
2. On first launch, click Settings and enter your Meshy API key (msy_...)
3. The key is stored locally at %APPDATA%\MeshyRhino\settings.json

Generating a 3D Model

1. Run the Meshy3DGenerator command
2. Choose a tab: Text-to-3D, Image-to-3D, Multi-Image-to-3D, or Text-to-Texture
3. Enter your prompt or select image(s)
4. Configure generation options:
   • AI Model: Meshy-6 (latest) or Meshy-5
   • Model Type: Standard or Low Poly
   • Topology: Triangle or Quad mesh
   • Target Polycount: 100 -- 300,000
   • Symmetry: Auto, On, or Off
   • PBR Maps: Enable metallic, roughness, and normal map generation
   • Remove Lighting: Strip highlights/shadows for cleaner results under custom lighting
5. Select output format:
   • GLB (Native Import) (default): Uses Rhino's built-in importer for full PBR material support
   • OBJ (Custom Parser): Parses OBJ geometry and downloads textures; choose Mesh Object or Block Instance placement
6. Click Generate -- the plugin submits the task, shows real-time progress with a thumbnail preview, and places the result in Rhino
7. Click Cancel at any time to abort an in-progress generation

Text-to-Texture (Retexture)

1. Switch to the Text-to-Texture tab
2. Provide a source model:
   • From previous task ID: Enter the ID of a completed Text-to-3D or Image-to-3D task
   • From model file: Browse for a .glb, .obj, .fbx, or .stl file
3. Choose a style source:
   • Text prompt: Describe the desired texture
   • Reference image: Select a .jpg or .png image
4. Optionally toggle "Preserve original UVs"
5. Click Retexture

Settings

Click Settings in the generator window to configure:

• API Key: Your Meshy API key
• Default AI Model, Model Type, Topology, Polycount, Symmetry, Format: Saved and applied automatically on launch
• Enable PBR: Default PBR map generation toggle
• Poll Interval: How frequently to check task progress (ms)
• API Retry Count: Number of retries for transient failures

How It Works

1. User input is collected in a modeless WPF window (Rhino remains interactive)
2. API calls and model download run on a background thread with configurable retry logic
3. GLB mode: The downloaded GLB file is imported via Rhino's native _-Import command, preserving PBR materials. The temp file is cleaned up after import.
4. OBJ mode: The downloaded OBJ is parsed with per-face-vertex UV splitting (no seam artifacts). Vertex coordinates are converted from meters to the document's unit system via RhinoMath.UnitScale. Textures are saved to %APPDATA%\MeshyRhino\textures\ so material references persist.
5. The mesh is placed in the document on Rhino's main thread via RhinoApp.InvokeOnUiThread
6. A thumbnail preview is displayed after generation completes (loaded from the API's thumbnail_url)

Build

# Build for Release
dotnet build Meshy-Rhino.sln --configuration Release

# Build for Debug
dotnet build Meshy-Rhino.sln --configuration Debug

Troubleshooting

Plugin does not load in Rhino:

• Ensure you are running Rhino 8 on Windows
• Check that all DLLs from the release zip are in the same folder
• Try running _PlugInManager and verify the plugin is listed and enabled

API key rejected:

• Ensure your key starts with msy_ and has not been revoked
• Check your internet connection
• Verify credits are available on your Meshy account

Mesh not appearing:

• Make sure a document is open in Rhino
• Check the Rhino command line for error messages
• Very high polycount meshes may need the target reduced

Network timeouts:

• Increase the retry count in Settings (default: 2)
• Check your internet stability
• Large GLB files may need up to 5 minutes to download

API Reference

This plugin uses the Meshy REST API:

Endpoint	Method	Purpose
/openapi/v2/text-to-3d	POST	Create text-to-3D task (preview or refine)
/openapi/v2/text-to-3d/:id	GET	Retrieve task status and model URLs
/openapi/v1/image-to-3d	POST	Create image-to-3D task
/openapi/v1/image-to-3d/:id	GET	Retrieve task status and model URLs
/openapi/v1/multi-image-to-3d	POST	Create multi-image-to-3D task
/openapi/v1/multi-image-to-3d/:id	GET	Retrieve task status and model URLs
/openapi/v1/retexture	POST	Create text-to-texture retexture task
/openapi/v1/retexture/:id	GET	Retrieve retexture task status and model URLs

Authentication: Authorization: Bearer msy_... header on all requests.

Contributing

Contributions are welcome. Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/YourFeature)
3. Commit your changes (git commit -m 'Add YourFeature')
4. Push to the branch (git push origin feature/YourFeature)
5. Open a Pull Request

Changelog

Version 0.3.0 (Current)

• Text-to-Texture (Retexture): New tab for applying textures to existing models via text prompts or reference images, using the /openapi/v1/retexture endpoint
• Expanded settings window: Configure all defaults (AI model, model type, topology, polycount, symmetry, format, PBR, poll interval, retry count) -- not just the API key
• Persistent defaults: Saved settings are automatically applied when the generator window opens; re-applied after editing settings
• Preview-only mode: Skip the refine step in Text-to-3D for faster/cheaper preview mesh generation
• Thumbnail preview: Shows the generated model thumbnail in the UI after task completion
• New generation options: Model type (standard/low poly), symmetry mode (auto/on/off), remove lighting toggle
• Retry logic: Automatic retry with exponential backoff for API calls and downloads (configurable retry count)
• Yak package manifest: manifest.yml included for Rhino package manager distribution
• Version bump to 0.3.0

Version 0.2.0

• GLB native import as the default format with full PBR material preservation
• OBJ import with per-face-vertex UV splitting for correct texture seam rendering
• Cancel button for aborting in-progress generation tasks
• Temp file cleanup after GLB import; persistent texture storage for OBJ
• Stable assembly and plugin GUIDs for consistent Rhino plugin identity
• Filename sanitization for prompts containing special characters
• Download timeout configuration to handle large files reliably
• Settings window properly owned by Rhino on first launch

Version 0.1.0

• Initial release
• Text-to-3D with preview + refine workflow
• Image-to-3D single image generation
• Multi-Image-to-3D (1-4 images)
• Mesh Object and Block Instance output modes
• Unit-aware placement (meters to document units)
• Configurable topology, polycount, AI model, and PBR options
• Modeless WPF UI with real-time progress tracking
• API key persistence to user AppData

License

This project is licensed under the GNU General Public License v3.0.

Support

• Meshy Documentation: docs.meshy.ai
• Issues: Report via the repository issue tracker

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Made by QROST