PBR Materials

Create and configure physically-based rendering materials with multiple texture channels for realistic rendering.

Usage

/blockbench-pbr <action> [args]

Actions:

• create <name> - Create a new PBR material
• configure <material> - Set material properties
• channel <material> <channel> - Assign texture to channel
• list - List all materials
• export <material> - Export texture_set.json

Prerequisites

• Blockbench must be running with the MCP plugin enabled
• PBR materials plugin may be required depending on format

Steps

Creating PBR Materials

1. Create material using mcp__blockbench__create_pbr_material:

   {
     "name": "metal_surface",
     "channels": ["color", "normal", "mer"]
   }
   

   • name: Material identifier
   • channels: Which PBR channels to enable

Configuring Materials

1. Configure properties using mcp__blockbench__configure_material:

   {
     "material_uuid": "<uuid>",
     "metalness": 1.0,
     "roughness": 0.3,
     "emissive": 0.0,
     "subsurface_scattering": false
   }
   

   • metalness: 0.0 (dielectric) to 1.0 (metal)
   • roughness: 0.0 (smooth/shiny) to 1.0 (rough/matte)
   • emissive: Emission intensity
   • subsurface_scattering: Enable SSS for skin/wax/etc.

Assigning Texture Channels

1. Assign texture using mcp__blockbench__assign_texture_channel:

   {
     "material_uuid": "<material-uuid>",
     "channel": "normal",
     "texture_uuid": "<texture-uuid>"
   }
   

Managing Materials

1. List materials using mcp__blockbench__list_materials:

   • Returns all PBR materials in the project
   • Includes channel assignments

2. Get material info using mcp__blockbench__get_material_info:

   • material_uuid: Material to inspect
   • Returns full configuration
   • Includes texture_set.json preview

Import/Export

1. Import texture set using mcp__blockbench__import_texture_set:

   • path: Path to texture_set.json
   • Imports Bedrock/RTX format materials

2. Save material config using mcp__blockbench__save_material_config:

   • material_uuid: Material to export
   • path: Output path
   • Exports texture_set.json format

PBR Channels

Channel	Description	Format
color	Base color/albedo	RGB
normal	Surface normals	RGB (tangent space)
mer	Metalness/Emissive/Roughness	RGB packed
metalness	Metallic property	Grayscale
roughness	Surface roughness	Grayscale
emissive	Light emission	RGB
heightmap	Displacement/parallax	Grayscale
ao	Ambient occlusion	Grayscale

MER Channel Packing

The MER texture packs three properties into RGB:

• R: Metalness (0-255 maps to 0.0-1.0)
• G: Emissive (0-255 maps to 0.0-1.0)
• B: Roughness (0-255 maps to 0.0-1.0)

Common Material Presets

Material	Metalness	Roughness	Notes
Metal	1.0	0.3-0.5	Reflective
Plastic	0.0	0.4-0.6	Slight sheen
Wood	0.0	0.7-0.9	Matte
Glass	0.0	0.0-0.1	Very smooth
Stone	0.0	0.8-1.0	Very rough
Skin	0.0	0.5	Enable SSS

Example Workflow

User: Create a metallic machine material

1. Create PBR material "machine_metal" with channels [color, normal, mer]
2. Configure: metalness 1.0, roughness 0.4
3. Create/assign color texture with base metal color
4. Create/assign normal texture for surface detail
5. Create MER texture:
   - R channel: 255 (full metalness)
   - G channel: 0 (no emission)
   - B channel: 102 (0.4 roughness)
6. Assign MER texture to mer channel
7. Export texture_set.json for Bedrock/RTX

Integration with Fabrica

For Hytale models, PBR is handled through shading modes:

• Use fullbright shading for emissive surfaces
• Use reflective shading for metallic surfaces
• Standard PBR export is for Bedrock/RTX rendering

texture_set.json Format

{
  "format_version": "1.16.100",
  "minecraft:texture_set": {
    "color": "machine_color",
    "normal": "machine_normal",
    "metalness_emissive_roughness": "machine_mer"
  }
}