Camera.cpp

#include "Camera.h"
#include <iostream>

Camera::Camera()
{
    c.identity();
    e.set(0.0, 0.5, 2.0);
    d.set(0.0, 0.0, 0.0);
    up.set(0.0, 1.0, 0.0);
    
    //Pre-define a camera matrix (and its inverse) that are shifted 'e' from the origin
    //This is used as a default camera position for Project 1
    c.set(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, e[0], e[1], e[2], 1);
    ci.set(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, -e[0], -e[1], -e[2], 1);
	update();
}

Camera::~Camera()
{
    //Delete and dynamically allocated memory/objects here
}

Matrix4& Camera::getMatrix()
{
    return c;
}

Matrix4& Camera::getInverseMatrix()
{
    return ci;
}

void Camera::update()
{
    //Update the Camera Matrix using d, e, and up
    //Solve for the z, x, and y axes of the camera matrix
    //Use these axes and the e vector to create a camera matrix c
    //Use c to solve for an inverse camera matrix ci
	Vector3 z = (e - d).normalize();
	Vector3 x = up.cross(z).normalize();
	Vector3 y = z.cross(x);

	c.set(x[0], x[1], x[2], 0, y[0], y[1], y[2], 0, z[0], z[1], z[2], 0, e[0], e[1], e[2], 1);
	ci = c.rigidInverse();
}

void Camera::set(Vector3& e, Vector3& d, Vector3& up)
{
    this->e = e;
    this->d = d;
    this->up = up;
    update();
}