src/Maths/Geometry/Triangle.php
public function isValidPoint(PointInterface $a)
    {
        return (bool) (
            $this->getSegmentAB()->isValidPoint($a) ||
            $this->getSegmentBC()->isValidPoint($a) ||
            $this->getSegmentCA()->isValidPoint($a)
        );
    }
public function isValidPoint(PointInterface $a)
    {
        return (bool) (
            $this->getSegmentAB()->isValidPoint($a) ||
            $this->getSegmentBC()->isValidPoint($a) ||
            $this->getSegmentCA()->isValidPoint($a)
        );
    }
Test if point A is in one of the triangle's segments

@param   \Maths\PointInterface   $a
@return  bool