Cylindrical Face Radius Embedding

This feature adds automatic radius information embedding for cylindrical faces in BREP solids, making the radius values available for downstream operations like dimensioning.

Live Demos

How It Works

1. Automatic Radius Embedding

When cylindrical faces are created, the system automatically stores radius metadata:

javascript 
// For primitive cylinders
const cylinder = new BREP.Cylinder({
    radius: 5.0,
    height: 10.0,
    name: 'MyCylinder'
});

// The side face 'MyCylinder_S' will automatically have metadata:
// {
//   type: 'cylindrical',
//   radius: 5.0,
//   height: 10.0,
//   axis: [0, 1, 0],
//   center: [0, 5.0, 0]
// }

2. Extrude Operations

When extruding circular sketches, cylindrical faces are automatically detected and radius metadata is embedded:

javascript 
// If you extrude a circular face with radius 3.0
const extruded = new BREP.ExtrudeSolid({
    face: circularFace,
    distance: 8.0
});

// The side wall will have cylindrical metadata with radius: 3.0

3. Accessing Face Metadata

You can retrieve the embedded radius information:

javascript 
// Get metadata for a specific face
const metadata = solid.getFaceMetadata('MyCylinder_S');

if (metadata && metadata.type === 'cylindrical') {
    console.log('Radius:', metadata.radius);
    console.log('Height:', metadata.height);
    console.log('Axis:', metadata.axis);
    console.log('Center:', metadata.center);
}

4. Setting Custom Metadata

You can also manually set face metadata:

javascript 
solid.setFaceMetadata('CustomFace', {
    type: 'cylindrical',
    radius: 7.5,
    height: 12.0,
    axis: [1, 0, 0],
    center: [0, 0, 0]
});

Benefits for Dimensioning

Radial Dimensions

The PMI system automatically uses embedded radius values when creating radial dimensions:

  1. Automatic Detection: When you select a cylindrical face for dimensioning, the system first checks for embedded radius metadata
  2. Precise Values: Uses the exact radius value from the original geometry instead of approximating from triangle vertices
  3. Performance: No need to perform geometric calculations to determine the radius

Usage in PMI Mode

javascript 
// In PMI mode, when creating a radial dimension:
// 1. Select the cylindrical face edge
// 2. The system automatically detects the embedded radius
// 3. Displays the correct radius value for dimensioning

Metadata Persistence

Face metadata is automatically preserved through:

  • Boolean Operations: Union, subtract, intersect operations preserve metadata from both input solids
  • Transformations: Metadata travels with the face through transformations
  • Feature Operations: Fillets, chamfers, and other operations maintain source metadata when possible

Supported Face Types

  • Cylindrical: Full circular cylinders with consistent radius
  • Conical: Truncated cones (when top/bottom radii are equal, treated as cylindrical)
  • Future: Spherical, toroidal, and other curved surfaces can be added using the same pattern

Implementation Notes

The system uses a Map to store face metadata:

  • Key: Face name (string)
  • Value: Metadata object with type, geometric parameters

This approach is:

  • Lightweight: Only stores essential geometric information
  • Extensible: Easy to add new face types and metadata
  • Compatible: Works with existing BREP boolean operations
  • Robust: Gracefully handles missing or invalid metadata