RayCast: Blender to JavaScript Ray Tracer

This project provides a web-based ray tracer that can render scenes exported from Blender.

Features

• Modular JavaScript ray tracer with physically-based rendering
• Blender add-on for exporting scenes
• Interactive rendering with adjustable camera and lighting parameters
• Support for various material types: Lambertian, Metal, Dielectric, Emissive
• Background options: Sky gradient, solid color, HDRI, procedural sky
• Post-processing effects: Tone mapping, anti-aliasing, denoising

Getting Started

Installing the Blender Add-on

1. Launch Blender
2. Go to Edit > Preferences > Add-ons
3. Click "Install..." and select the blender_addon/raycast_exporter.py file
4. Enable the "Import-Export: RayCast Exporter" add-on

Exporting a Scene from Blender

1. Create your scene in Blender
2. Go to the 3D View sidebar (press N if not visible)
3. Look for the "RayCast" tab
4. Click "Export Scene"
5. Choose where to save the JSON file

Rendering in the Ray Tracer

1. Open index.html in a web browser
2. Use the "Import Blender JSON" option to select your exported scene
3. Click "Import Blender Scene"
4. Adjust rendering parameters as needed
5. Click "Render Scene"

Supported Geometry

• Spheres
• Boxes
• Planes
• Triangles
• Triangle Meshes (for arbitrary 3D models)

Supported Materials

• Lambertian: Diffuse surfaces
• Metal: Reflective surfaces with adjustable roughness
• Dielectric: Glass and other transparent materials
• Emissive: Light-emitting surfaces

Scene Format

The exported JSON from Blender follows this structure:

{
  "name": "Scene Name",
  "objects": [
    {
      "type": "sphere",
      "name": "Sphere1",
      "center": [0, 0, -1],
      "radius": 0.5,
      "material": {
        "type": "lambertian",
        "color": [1.0, 0.2, 0.2]
      }
    }
    // More objects...
  ],
  "lights": [
    {
      "type": "point",
      "position": [0, 5, 5],
      "color": [1, 1, 1],
      "intensity": 8.0
    }
    // More lights...
  ],
  "camera": {
    "position": [0, 1, 3],
    "lookAt": [0, 0, -1],
    "up": [0, 1, 0],
    "fov": 40,
    "aspect": 1.5,
    "aperture": 0.05,
    "focusDist": 4.0,
    "type": "perspective"
  },
  "background": {
    "type": "gradient",
    "intensity": 1.0
  }
}

Future Improvements

• Improved mesh optimization (BVH acceleration structures)
• Texture mapping
• More material types
• Animation support
• Environment mapping
• Two-way integration (open ray tracer from Blender)

License

This project is licensed under the MIT License - see the LICENSE file for details.