float _diagonalSupport(Offset centersVector, _Diagonal diagonal)
{
Offset delta = this._cornerFor(this.begin, diagonal.endId) - this._cornerFor(this.begin, diagonal.beginId);
float length = delta.distance;
return(centersVector.dx * delta.dx / length + centersVector.dy * delta.dy / length);
}
void _initialize()
{
D.assert(this.begin != null);
D.assert(this.end != null);
Offset centersVector = this.end.center - this.begin.center;
_Diagonal diagonal = ArcUtils._maxBy(ArcUtils._allDiagonals,
(_Diagonal d) => this._diagonalSupport(centersVector, d));
this._beginArc = new MaterialPointArcTween(
begin: this._cornerFor(this.begin, diagonal.beginId),
end: this._cornerFor(this.end, diagonal.beginId));
this._endArc = new MaterialPointArcTween(
begin: this._cornerFor(this.begin, diagonal.endId),
end: this._cornerFor(this.end, diagonal.endId));
this._dirty = false;
}
