// Create shapes
double[] normal = Math2.MINUS_Z_AXIS;
double[] center = Math2.ORIGIN_3D;
Shape sphere = new Sphere(center, radius);
Shape upPlane = MultiPlaneShape.createSubstrate(normal, center);
Shape inclusionShape = new ShapeDifference(sphere, upPlane);
normal = Math2.Z_AXIS;
Shape downPlane = MultiPlaneShape.createSubstrate(normal, center);
Shape substrateShape =
new ShapeDifference(downPlane, sphere);
// Add shape to chamber
new IndexedRegion(chamber, substrateMaterial, substrateShape, 1);
new IndexedRegion(chamber, inclusionMaterial, inclusionShape, 2);