source/js/deps/helpers.js
function transCalc(transFrom, transTo, progress) {
  var res={};
  for(var i in transFrom) {
    switch(i) {
      case 'rotate':
        res[i]=[0,0,0];
        for(var j=0;j<3;j++) {
          res[i][j]=transFrom[i][j]+(transTo[i][j]-transFrom[i][j])*progress;
        }
        break;
    }
  }
  return res;
}
function transCalc(transFrom, transTo, progress) {
  var res={};
  for(var i in transFrom) {
    switch(i) {
      case 'rotate':
        res[i]=[0,0,0];
        for(var j=0;j<3;j++) {
          res[i][j]=transFrom[i][j]+(transTo[i][j]-transFrom[i][j])*progress;
        }
        break;
    }
  }
  return res;
}
function transCalc ( transFrom , transTo , progress ) { var res = { } ; for ( var i in transFrom ) { switch ( i ) { case 'rotate' : res [ i ] = [ 0 , 0 , 0 ] ; for ( var j = 0 ; j < 3 ; j ++ ) { res [ i ] [ j ] = transFrom [ i ] [ j ] + ( transTo [ i ] [ j ] - transFrom [ i ] [ j ] ) * progress ; } break ; } } return res ; }
Calculate transform progress
Calculate transform progress