{
 "id": "22-split-body",
 "name": "Split body by angled plane",
 "description": "Cylinder r=20, z from -30 to 30 (symmetric extrude) split by a plane containing the X axis tilted 30 deg from XY.",
 "exercises": [
  "extrude",
  "symmetric",
  "construction_plane_angle",
  "split_body"
 ],
 "units": {
  "length": "mm",
  "angle": "deg",
  "area": "mm2",
  "volume": "mm3"
 },
 "conventions": {
  "world": "right-handed; Z up. XY/XZ/YZ are the origin planes.",
  "sketch_frame": "sketch-local 2D coords; world = plane.origin + x*plane.x_dir + y*plane.y_dir (origin in mm). Profile 'loops' list sketch entity ids.",
  "point_refs": "'<id>.start' / '<id>.end' / '<id>.center' reuse (share) that existing sketch point; 'at' is its position when referenced.",
  "extrude_direction": "positive = along sketch plane normal unless stated",
  "selections": "selected faces/edges carry 'point': a world-space point on the face / the edge's parametric midpoint; pick the nearest face/edge to it."
 },
 "parameters": [],
 "features": [
  {
   "op": "sketch",
   "name": "Sketch1",
   "plane": {
    "ref": "XY",
    "origin": [
     0.0,
     0.0,
     0.0
    ],
    "x_dir": [
     1.0,
     0.0,
     0.0
    ],
    "y_dir": [
     0.0,
     1.0,
     0.0
    ],
    "normal": [
     0.0,
     0.0,
     1.0
    ]
   },
   "entities": [
    {
     "type": "circle",
     "center": {
      "at": [
       0,
       0
      ]
     },
     "radius": 20,
     "id": "c1"
    }
   ],
   "constraints": [],
   "dimensions": []
  },
  {
   "op": "extrude",
   "name": "Extrude1",
   "operation": "new",
   "profiles": [
    {
     "sketch": "Sketch1",
     "loops": [
      {
       "outer": true,
       "curves": [
        "c1"
       ]
      }
     ]
    }
   ],
   "extent": {
    "type": "symmetric",
    "distance": 30,
    "is_full_length": false,
    "meaning": "distance on each side"
   },
   "result_bodies": [
    "Cyl"
   ]
  },
  {
   "op": "construction_plane",
   "name": "Tilt30",
   "method": "at_angle",
   "axis": "world X axis",
   "base_plane": "XY",
   "angle": 30,
   "result_origin": [
    12.125,
    0.0,
    0.0
   ],
   "result_normal": [
    0.0,
    -0.5,
    0.866025404
   ]
  },
  {
   "op": "split_body",
   "name": "Split1",
   "body": "Cyl",
   "tool": "Tilt30",
   "extend_tool": true,
   "result_bodies": [
    "Cyl",
    "Cyl (1)"
   ]
  }
 ]
}