How to use robust-orientation - 6 common examples

export function orientation (point1, point2, point3) {
  if (robust) {
    const o = robustOrientation([point1.x, point1.y], [point2.x, point2.y], [point3.x, point3.y]);
    return o === 0 ? o : -o; // the y-axis is inverted
  } else {
    // return -((point1.y - point3.y) * (point2.x - point3.x) - (point1.x - point3.x) * (point2.y - point3.y));
    return (point2.x - point1.x) * (point3.y - point1.y) - (point2.y - point1.y) * (point3.x - point1.x);
  }
}

function incrementalConvexHull(points, randomSearch) {
  var n = points.length
  if(n === 0) {
    throw new Error("Must have at least d+1 points")
  }
  var d = points[0].length
  if(n <= d) {
    throw new Error("Must input at least d+1 points")
  }

  //FIXME: This could be degenerate, but need to select d+1 non-coplanar points to bootstrap process
  var initialSimplex = points.slice(0, d+1)

  //Make sure initial simplex is positively oriented
  var o = orient.apply(void 0, initialSimplex)
  if(o === 0) {
    throw new Error("Input not in general position")
  }
  var initialCoords = new Array(d+1)
  for(var i=0; i<=d; ++i) {
    initialCoords[i] = i
  }
  if(o < 0) {
    initialCoords[0] = 1
    initialCoords[1] = 0
  }

  //Create initial topological index, glue pointers together (kind of messy)
  var initialCell = new Simplex(initialCoords, new Array(d+1), false)
  var boundary = initialCell.adjacent
  var list = new Array(d+2)

function linearlyIndependent(points, d) {
  var nhull = new Array(d+1)
  for(var i=0; i

proto.degenerate = function() {
  var pointList = new Array(this.vertices.length)
  for(var i=0; i

function incrementalConvexHull(points, randomSearch) {
  var n = points.length
  if(n === 0) {
    throw new Error("Must have at least d+1 points")
  }
  var d = points[0].length
  if(n <= d) {
    throw new Error("Must input at least d+1 points")
  }

  //FIXME: This could be degenerate, but need to select d+1 non-coplanar points to bootstrap process
  var initialSimplex = points.slice(0, d+1)

  //Make sure initial simplex is positively oriented
  var o = orient.apply(void 0, initialSimplex)
  if(o === 0) {
    throw new Error("Input not in general position")
  }
  var initialCoords = new Array(d+1)
  for(var i=0; i<=d; ++i) {
    initialCoords[i] = i
  }
  if(o < 0) {
    initialCoords[0] = 1
    initialCoords[1] = 0
  }

  //Create initial topological index, glue pointers together (kind of messy)
  var initialCell = new Simplex(initialCoords, new Array(d+1), false)
  var boundary = initialCell.adjacent
  var list = new Array(d+2)

function linearlyIndependent(points, d) {
  var nhull = new Array(d+1)
  for(var i=0; i