CINEMA4D: Script Points to Circle

/***************************************************
Points to Circle
David Wickenden 2007
****************************************************/

main(doc,op)
{
  var radius = 50; //Enter radius value here.

  if(!doc->GetActiveObject()) return;
  if(!instanceof(op, PolygonObject)) return;

  var bc = new(BaseContainer);
  bc->SetData(MDATA_CONVERTSELECTION_LEFT, 0);
  bc->SetData(MDATA_CONVERTSELECTION_RIGHT, 1);
 
  SendModelingCommand(MCOMMAND_CONVERTSELECTION, doc, op, bc, MODIFY_POINTSELECTION);
  SendModelingCommand(MCOMMAND_EDGE_TO_SPLINE, doc, op, bc, MODIFY_EDGESELECTION);

  if(!op->GetDown()) return;
  if(op->GetDown()->GetType() != OBJECT_SPLINE) return;

  var pointCnt = op->GetPointCount();
  var pointSel = op->GetPointSelection();
  var pointSelCnt = pointSel->GetCount();

  var spline = op->GetDown();
  var spPointCnt = spline->GetPointCount();
  var spPointSel = spline->GetPointSelection();
  var spPointSelCnt = spPointSel->GetCount();

  if(spPointCnt != pointSelCnt) return;

  var arr = new(array, pointCnt, 2);

  var i, j, k = 0;
  var found = 0;

  for(i = 0; i < pointCnt; i++) 
  {
    if(found >= pointSelCnt) break;
    if(pointSel->IsSelected(i))
    {
      for(j = 0; j < spPointCnt; j++)
      {
        if(op->GetPoint(i) == spline->GetPoint(j)) 
        {
          arr[k][0] = i;
          arr[k][1] = j;
        }
      }   
      k++;
      found++;   
    }
  }

  var vectorSum = vector(0, 0, 0);
  var found = 0;

  for(i = 0; i < spPointCnt; i++) 
  {
    vectorSum = vectorSum + spline->GetPoint(i);
  }

  var mSp = spline->GetMg();
  var vectorAv = vectorSum / spPointCnt;
  var vectorAv_g = mSp->GetMulP(vectorAv);

  var refPointA = spline->GetPoint(0);
  var refPointB = spline->GetPoint(1);
  var refPointAg = mSp->GetMulP(refPointA);
  var refPointBg = mSp->GetMulP(refPointB);

  var m = new(Matrix);
 
  m->SetV0(vectorAv_g);
  m->SetV1(vnorm(refPointAg - vectorAv_g));
  var mV1 = m->GetV1();
  m->SetV3(vnorm(vcross(mV1, (refPointBg - vectorAv_g))));
  var mV3 = m->GetV3();
  m->SetV2(vnorm(vcross(mV3, mV1)));

  var angle = 6.283 / spPointCnt;
  var mOp = op->GetMg();
  var k;

  for(k = 0; k < pointSelCnt; k++) 
  {
    var pointA = spline->GetPoint(arr[k][1]);
    var pointAg = mSp->GetMulP(pointA);

    m->Invert(); //Local
    var pointAl = m->GetMulP(pointAg);
    var posAl_x = cos(angle * (arr[k][1])) * radius;
    var posAl_y = sin(angle * (arr[k][1])) * radius;
    var pointAlMod = vector(posAl_x, posAl_y, pointAl.z);

    m->Invert(); //Global
    var pointAg2 = m->GetMulP(pointAlMod);

    mOp->Invert(); //Local
    var pointAl2 = mOp->GetMulP(pointAg2);

    op->SetPoint(arr[k][0], pointAl2); 
    mOp->Invert(); //Global
  }
  spline->Remove();
  op->Message(MSG_UPDATE);
}