Ray.cpp

#include "Ray.h"

//not dependent
#include <iostream>
Ray::Ray()
{
}

Ray::Ray(const Vector3f& origin, const Vector3f& direction)
    : origin(origin), direction(direction)
{
}

/* Takes a parameter t and returns the point accoring to t. t is the parametric variable in the ray equation o+t*d.*/
Vector3f Ray::getPoint(float t) const 
{
	/***********************************************
     *                                             *
	 * TODO: Implement this function               *
     *                                             *
     ***********************************************
	 */

    Vector3f pointAtT;
    pointAtT = vectorAddition(origin,scalarMultiplication(t, direction));

    return pointAtT;
}

/* Takes a point p and returns the parameter t according to p such that p = o+t*d. */
float Ray::gett(const Vector3f & p) const
{
	/***********************************************
     *                                             *
	 * TODO: Implement this function               *
     *                                             *
     ***********************************************
	 */

    Vector3f vectorFromOriginToPoint = vectorSubtraction(p, origin);

    return dotProduct(vectorFromOriginToPoint, direction) / dotProduct(direction, direction);

}

Vector3f Ray::scalarMultiplication(float t, Vector3f direction) const{
    Vector3f result;

    result.x = direction.x * t;
    result.y = direction.y * t;
    result.z = direction.z * t;

    return result;
}

Vector3f Ray::vectorSubtraction(Vector3f a, Vector3f b) const{
    Vector3f result;
    
    result.x = a.x - b.x;
    result.y = a.y - b.y;
    result.z = a.z - b.z;

    return result;

}
Vector3f Ray::vectorAddition(Vector3f a, Vector3f b) const{
    Vector3f result;
    
    result.x = a.x + b.x;
    result.y = a.y + b.y;
    result.z = a.z + b.z;

    return result;

}

float Ray::dotProduct(Vector3f a, Vector3f b) const{
    
    return (a.x * b.x) + (a.y * b.y) + (a.z * b.z);
}