planewave.h
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#ifndef STIM_PLANEWAVE_H
#define STIM_PLANEWAVE_H
#include <string>
#include <sstream>
#include <cmath>
#include "../math/vec3.h"
#include "../math/quaternion.h"
#include "../math/constants.h"
#include "../math/plane.h"
#include <complex>
/// Calculate whether or not a vector v intersects the front (1) or back (-1) of a plane.
/// This function returns -1 if the vector lies within the plane (is orthogonal to the surface normal)
/*template <typename T>
int plane_face(stim::vec3<T> v, stim::vec3<T> plane_normal) {
T dotprod = v.dot(plane_normal); //calculate the dot product
if (dotprod < 0) return 1;
if (dotprod > 0) return -1;
return 0;
}
/// Calculate the component of a vector v that is perpendicular to a plane defined by a normal.
template <typename T>
stim::vec3<T> plane_perpendicular(stim::vec3<T> v, stim::vec3<T> plane_normal) {
return plane_normal * v.dot(plane_normal);
}
template <typename T>
stim::vec3<T> plane_parallel(stim::vec3<T> v, stim::vec3<T> plane_normal) {
return v - plane_perpendicular(v, plane_normal);
}*/
namespace stim{
namespace optics{
/// evaluate the scalar field produced by a plane wave at a point (x, y, z)
/// @param x is the x-coordinate of the point
/// @param y is the y-coordinate of the point
/// @param z is the z-coordinate of the point
/// @param A is the amplitude of the plane wave, specifically the field at (0, 0, 0)
/// @param kx is the k-vector component in the x direction
/// @param ky is the k-vector component in the y direction
/// @param kz is the k-vector component in the z direction
template<typename T>
std::complex<T> planewave_scalar(T x, T y, T z, std::complex<T> A, T kx, T ky, T kz){
T d = x * kx + y * ky + z * kz; //calculate the dot product between k and p = (x, y, z) to find the distance p is along the propagation direction
std::complex<T> di = std::complex<T>(0, d); //calculate the phase shift that will have to be applied to propagate the wave distance d
return A * exp(di); //multiply the phase term by the amplitude at (0, 0, 0) to propagate the wave to p
}
/// evaluate the scalar field produced by a plane wave at several positions
/// @param field is a pre-allocated block of memory that will store the complex field at all points
/// @param N is the number of field values to be evaluated
/// @param x is a set of x coordinates defining positions within the field (NULL implies that all values are zero)
/// @param y is a set of y coordinates defining positions within the field (NULL implies that all values are zero)
/// @param z is a set of z coordinates defining positions within the field (NULL implies that all values are zero)
/// @param A is the amplitude of the plane wave, specifically the field at (0, 0, 0)
/// @param kx is the k-vector component in the x direction
/// @param ky is the k-vector component in the y direction
/// @param kz is the k-vector component in the z direction
template<typename T>
void cpu_planewave_scalar(std::complex<T>* field, size_t N, T* x, T* y = NULL, T* z = NULL, std::complex<T> A = 1.0, T kx = 0.0, T ky = 0.0, T kz = 0.0){
T px, py, pz;
for(size_t i = 0; i < N; i++){ // for each element in the array
(x == NULL) ? px = 0 : px = x[i]; // test for NULL values
(y == NULL) ? py = 0 : py = y[i];
(z == NULL) ? pz = 0 : pz = z[i];
field[i] = planewave_scalar(px, py, pz, A, kx, ky, kz); // call the single-value plane wave function
}
}
/*template<typename T>
class cvec3 {
public:
std::complex<T> x;
std::complex<T> y;
std::complex<T> z;
cvec3(std::complex<T> _x, std::complex<T> _y, std::complex<T> _z) {
x = _x;
y = _y;
z = _z;
}
};*/
/*template<typename T>
class cvec3 {
public:
std::complex<T> m_v[3];
cvec3(std::complex<T> x, std::complex<T> y, std::complex<T> z) {
m_v[0] = x;
m_v[1] = y;
m_v[2] = z;
}
cvec3() : cvec3(0, 0, 0) {}
void operator()(std::complex<T> x, std::complex<T> y, std::complex<T> z) {
m_v[0] = x;
m_v[1] = y;
m_v[2] = z;
}
std::complex<T> operator[](int i) const { return m_v[i]; }
std::complex<T>& operator[](int i) { return m_v[i]; }
/// Calculate the 2-norm of the complex vector
T norm2() {
T xx = std::real(m_v[0] * std::conj(m_v[0]));
T yy = std::real(m_v[1] * std::conj(m_v[1]));
T zz = std::real(m_v[2] * std::conj(m_v[2]));
return std::sqrt(xx + yy + zz);
}
/// Returns the normalized direction vector
cvec3 direction() {
cvec3 result;
std::complex<T> length = norm2();
result[0] = m_v[0] / length;
result[1] = m_v[1] / length;
result[2] = m_v[2] / length;
return result;
}
std::string str() {
std::stringstream ss;
ss << m_v[0] << ", " << m_v[1] << ", " << m_v[2];
return ss.str();
}
//copy constructor
cvec3(const cvec3 &other) {
m_v[0] = other.m_v[0];
m_v[1] = other.m_v[1];
m_v[2] = other.m_v[2];
}
/// Assignment operator
cvec3& operator=(const cvec3 &rhs) {
m_v[0] = rhs.m_v[0];
m_v[1] = rhs.m_v[1];
m_v[2] = rhs.m_v[2];
return *this;
}
/// Calculate and return the cross product between this vector and another
cvec3 cross(cvec3 rhs) {
cvec3 result;
//compute the cross product (only valid for 3D vectors)
result[0] = (m_v[1] * rhs[2] - m_v[2] * rhs[1]);
result[1] = (m_v[2] * rhs[0] - m_v[0] * rhs[2]);
result[2] = (m_v[1] * rhs[1] - m_v[1] * rhs[0]);
return result;
}
/// Calculate and return the dot product between this vector and another
std::complex<T> dot(cvec3 rhs) {
return m_v[0] * rhs[0] + m_v[1] * rhs[1] + m_v[2] * rhs[2];
}
/// Arithmetic multiplication: returns the vector scaled by a constant value
template<typename R>
cvec3 operator*(R rhs) const
{
cvec3 result;
result[0] = m_v[0] * rhs;
result[1] = m_v[1] * rhs;
result[2] = m_v[2] * rhs;
return result;
}
};
template <typename T>
std::ostream& operator<<(std::ostream& os, stim::optics::cvec3<T> p) {
os << p.str();
return os;
}
*/
template<typename T>
class planewave{
protected:
cvec3<T> m_k; //k-vector, pointed in propagation direction with magnitude |k| = tau / lambda = 2pi / lambda
cvec3<T> m_E; //amplitude (for a scalar plane wave, only E0[0] is used)
/// Bend a plane wave via refraction, given that the new propagation direction is known
CUDA_CALLABLE planewave<T> bend(stim::vec3<T> v) const {
stim::vec3<T> k_real(m_k.get(0).real(), m_k.get(1).real(), m_k.get(2).real()); //force the vector to be real (can only refract real directions)
stim::vec3<T> kn_hat = v.direction(); //normalize the new k
stim::vec3<T> k_hat = k_real.direction(); //normalize the current k
planewave<T> new_p; //create a new plane wave
T k_dot_kn = k_hat.dot(kn_hat); //if kn is equal to k or -k, handle the degenerate case
//if k . n < 0, then the bend is a reflection
if(k_dot_kn < 0) k_hat = -k_hat; //flip k_hat
if(k_dot_kn == -1){
new_p.m_k = -m_k;
new_p.m_E = m_E;
return new_p;
}
else if(k_dot_kn == 1){
new_p.m_k = m_k;
new_p.m_E = m_E;
return new_p;
}
vec3<T> r = k_hat.cross(kn_hat); //compute the rotation vector
T theta = asin(r.len()); //compute the angle of the rotation about r
quaternion<T> q; //create a quaternion to capture the rotation
q.CreateRotation(theta, r.direction());
stim::matrix_sq<T, 3> R = q.toMatrix3();
vec3< std::complex<T> > E(m_E.get(0), m_E.get(1), m_E.get(2));
vec3< std::complex<T> > E0n = R * E; //apply the rotation to E0
//new_p.m_k = kn_hat * kmag();
//new_p.m_E = E0n;
new_p.m_k[0] = kn_hat[0] * kmag();
new_p.m_k[1] = kn_hat[1] * kmag();
new_p.m_k[2] = kn_hat[2] * kmag();
new_p.m_E[0] = E0n[0];
new_p.m_E[1] = E0n[1];
new_p.m_E[2] = E0n[2];
return new_p;
}
public:
///constructor: create a plane wave propagating along k
//CUDA_CALLABLE planewave(vec<T> kvec = stim::vec<T>(0, 0, stim::TAU),
// vec< complex<T> > E = stim::vec<T>(1, 0, 0))
CUDA_CALLABLE planewave(std::complex<T> kx, std::complex<T> ky, std::complex<T> kz,
std::complex<T> Ex, std::complex<T> Ey, std::complex<T> Ez) {
m_k = cvec3<T>(kx, ky, kz);
m_E = cvec3<T>(Ex, Ey, Ez);
force_orthogonal();
}
CUDA_CALLABLE planewave() : planewave(0, 0, 1, 1, 0, 0) {}
//copy constructor
CUDA_CALLABLE planewave(const planewave& other) {
m_k = other.m_k;
m_E = other.m_E;
}
/// Assignment operator
CUDA_CALLABLE planewave& operator=(const planewave& rhs) {
m_k = rhs.m_k;
m_E = rhs.m_E;
return *this;
}
/// Forces the k and E vectors to be orthogonal
CUDA_CALLABLE void force_orthogonal() {
/*if (m_E.norm2() == 0) return;
cvec3<T> k_dir = m_k.direction(); //calculate the normalized direction vectors for k and E
cvec3<T> E_dir = m_E.direction();
cvec3<T> side = k_dir.cross(E_dir); //calculate a side vector for projection
cvec3<T> side_dir = side.direction(); //normalize the side vector
E_dir = side_dir.cross(k_dir); //calculate the new E vector direction
T E_norm = m_E.norm2();
m_E = E_dir * E_norm; //apply the new direction to the existing E vector
*/
}
CUDA_CALLABLE cvec3<T> k() {
return m_k;
}
CUDA_CALLABLE cvec3<T> E() {
return m_E;
}
CUDA_CALLABLE cvec3<T> evaluate(T x, T y, T z) {
std::complex<T> k_dot_r = m_k[0] * x + m_k[1] * y + m_k[2] * z;
std::complex<T> e_k_dot_r = std::exp(std::complex<T>(0, 1) * k_dot_r);
cvec3<T> result;
result[0] = m_E[0] * e_k_dot_r;
result[1] = m_E[1] * e_k_dot_r;
result[2] = m_E[2] * e_k_dot_r;
return result;
}
/*int scatter(vec3<T> surface_normal, vec3<T> surface_point, T ni, std::complex<T> nt,
planewave& Pi, planewave& Pr, planewave& Pt) {
return 0;
}*/
CUDA_CALLABLE T kmag() const {
return std::sqrt(std::real(m_k.get(0) * std::conj(m_k.get(0)) + m_k.get(1) * std::conj(m_k.get(1)) + m_k.get(2) * std::conj(m_k.get(2))));
}
CUDA_CALLABLE planewave<T> refract(stim::vec3<T> kn) const {
return bend(kn);
}
/// Return a plane wave with the origin translated by (x, y, z)
CUDA_CALLABLE planewave<T> translate(T x, T y, T z) const {
planewave<T> result;
cvec3<T> k = m_k;
result.m_k = k;
std::complex<T> k_dot_r = k[0] * (-x) + k[1] * (-y) + k[2] * (-z);
std::complex<T> exp_k_dot_r = std::exp(std::complex<T>(0.0, 1.0) * k_dot_r);
cvec3<T> E = m_E;
result.m_E[0] = E[0] * exp_k_dot_r;
result.m_E[1] = E[1] * exp_k_dot_r;
result.m_E[2] = E[2] * exp_k_dot_r;
return result;
}
///multiplication operator: scale E0
CUDA_CALLABLE planewave<T>& operator* (const T& rhs) {
m_E = m_E * rhs;
return *this;
}
/*CUDA_CALLABLE T lambda() const{
return stim::TAU / k.len();
}
CUDA_CALLABLE T kmag() const{
return k.len();
}
CUDA_CALLABLE vec< complex<T> > E(){
return E0;
}
CUDA_CALLABLE vec<T> kvec(){
return k;
}
/// calculate the value of the field produced by the plane wave given a three-dimensional position
CUDA_CALLABLE vec< complex<T> > pos(T x, T y, T z){
return pos( stim::vec<T>(x, y, z) );
}
CUDA_CALLABLE vec< complex<T> > pos(vec<T> p = vec<T>(0, 0, 0)){
vec< complex<T> > result;
T kdp = k.dot(p);
complex<T> x = complex<T>(0, kdp);
complex<T> expx = exp(x);
result[0] = E0[0] * expx;
result[1] = E0[1] * expx;
result[2] = E0[2] * expx;
return result;
}
//scales k based on a transition from material ni to material nt
CUDA_CALLABLE planewave<T> n(T ni, T nt){
return planewave<T>(k * (nt / ni), E0);
}
CUDA_CALLABLE planewave<T> refract(stim::vec<T> kn) const{
return bend(kn);
}
/// Calculate the result of a plane wave hitting an interface between two refractive indices
/// @param P is a plane representing the position and orientation of the surface
/// @param n0 is the refractive index outside of the surface (in the direction of the normal)
/// @param n1 is the refractive index inside the surface (in the direction away from the normal)
/// @param r is the reflected component of the plane wave
/// @param t is the transmitted component of the plane wave
void scatter(stim::plane<T> P, T n0, T n1, planewave<T> &r, planewave<T> &t){
scatter(P, n1/n0, r, t);
}*/
/// Calculate the scattering result when nr = n1/n0
/// @param P is a plane representing the position and orientation of the surface
/// @param r is the ration n1/n0
/// @param n1 is the refractive index inside the surface (in the direction away from the normal)
/// @param r is the reflected component of the plane wave
/// @param t is the transmitted component of the plane wave
void scatter(vec3<T> plane_normal, vec3<T> plane_position, std::complex<T> nr, planewave<T>& r, planewave<T>& t) {
if (m_k[0].imag() != 0.0 || m_k[1].imag() != 0.0 || m_k[2].imag() != 0) {
std::cout << "ERROR: cannot scatter a plane wave with an imaginary k-vector." << std::endl;
}
stim::vec3<T> ki(m_k[0].real(), m_k[1].real(), m_k[2].real()); //force the current k vector to be real
stim::vec3<T> kr;
stim::cvec3<T> kt, Ei, Er, Et;
plane_normal = plane_normal.direction();
stim::vec3<T> k_dir = ki.direction(); // calculate the direction of the incident plane wave
int facing = plane_face(k_dir, plane_normal); //determine which direction the plane wave is coming in
if (facing == -1) { //if the wave hits the back of the plane, invert the plane and nr
std::cout << "ERROR: k-vector intersects the wrong side of the boundary." << std::endl;
return -1; //the plane wave is impacting the wrong side of the surface
}
//use Snell's Law to calculate the transmitted angle
T cos_theta_i = k_dir.dot(-plane_normal); //compute the cosine of theta_i
T sin_theta_i = std::sqrt(1 - cos_theta_i * cos_theta_i);
T theta_i = acos(cos_theta_i); //compute theta_i
//handle the degenerate case where theta_i is 0 (the plane wave hits head-on)
if (theta_i == 0) {
std::complex<T> rp = (1.0 - nr) / (1.0 + nr); //compute the Fresnel coefficients
std::complex<T> tp = 2.0 / (1.0 + nr);
//ki = kv * ni; //calculate the incident k-vector (scaled by the incident refractive index)
kr = -ki; //the reflection vector is the inverse of the incident vector
kt[0] = ki[0] * nr;
kt[1] = ki[1] * nr;
kt[2] = ki[2] * nr;
//Ei = Ev; //compute the E vectors for all three plane waves based on the Fresnel coefficients
Er = m_E * rp;
Et = m_E * tp;
//calculate the phase offset based on the plane positions
//T phase_i = plane_position.dot(kv - ki); //compute the phase offset for each plane wave
T phase_r = plane_position.dot(ki - kr);
std::complex<T> phase_t =
plane_position[0] * (ki[0] - kt[0]) +
plane_position[1] * (ki[1] - kt[1]) +
plane_position[2] * (ki[2] - kt[2]);
}
else {
T cos_theta_r = cos_theta_i;
T sin_theta_r = sin_theta_i;
T theta_r = theta_i;
std::complex<T> sin_theta_t = nr * sin(theta_i); //compute the sine of theta_t using Snell's law
std::complex<T> cos_theta_t = std::sqrt(1.0 - sin_theta_t * sin_theta_t);
std::complex<T> theta_t = asin(sin_theta_t); //compute the cosine of theta_t
//Define the basis vectors for the calculation (plane of incidence)
stim::vec3<T> z_hat = -plane_normal;
stim::vec3<T> y_hat = plane_parallel(k_dir, plane_normal);
stim::vec3<T> x_hat = y_hat.cross(z_hat);
//calculate the k-vector magnitudes
//T kv_mag = kv.norm2();
T ki_mag = ki.norm2();
T kr_mag = ki_mag;
std::complex<T> kt_mag = ki_mag * nr;
//calculate the k vector directions
stim::vec3<T> ki_dir = y_hat * sin_theta_i + z_hat * cos_theta_i;
stim::vec3<T> kr_dir = y_hat * sin_theta_r - z_hat * cos_theta_r;
stim::cvec3<T> kt_dir;
kt_dir[0] = y_hat[0] * sin_theta_t + z_hat[0] * cos_theta_t;
kt_dir[1] = y_hat[1] * sin_theta_t + z_hat[1] * cos_theta_t;
kt_dir[2] = y_hat[2] * sin_theta_t + z_hat[2] * cos_theta_t;
//calculate the k vectors
ki = ki_dir * ki_mag;
kr = kr_dir * kr_mag;
kt = kt_dir * kt_mag;
//calculate the Fresnel coefficients
std::complex<T> rs = std::sin(theta_t - theta_i) / std::sin(theta_t + theta_i);
std::complex<T> rp = std::tan(theta_t - theta_i) / std::tan(theta_t + theta_i);
std::complex<T> ts = (2.0 * (sin_theta_t * cos_theta_i)) / std::sin(theta_t + theta_i);
std::complex<T> tp = ((2.0 * sin_theta_t * cos_theta_i) / (std::sin(theta_t + theta_i) * std::cos(theta_t - theta_i)));
//calculate the p component directions for each E vector
stim::vec3<T> Eip_dir = y_hat * cos_theta_i - z_hat * sin_theta_i;
stim::vec3<T> Erp_dir = y_hat * cos_theta_r + z_hat * sin_theta_r;
stim::cvec3<T> Etp_dir;
Etp_dir[0] = y_hat[0] * cos_theta_t - z_hat[0] * sin_theta_t;
Etp_dir[1] = y_hat[1] * cos_theta_t - z_hat[1] * sin_theta_t;
Etp_dir[2] = y_hat[2] * cos_theta_t - z_hat[2] * sin_theta_t;
//calculate the s and t components of each E vector
//std::complex<T> E_mag = Ev.norm2();
std::complex<T> Ei_s = m_E.dot(x_hat);
//std::complex<T> Ei_p = std::sqrt(E_mag * E_mag - Ei_s * Ei_s);
std::complex<T> Ei_p = m_E.dot(Eip_dir);
std::complex<T> Er_s = rs * Ei_s;
std::complex<T> Er_p = rp * Ei_p;
std::complex<T> Et_s = ts * Ei_s;
std::complex<T> Et_p = tp * Ei_p;
//calculate the E vector for each plane wave
//Ei[0] = Eip_dir[0] * Ei_p + x_hat[0] * Ei_s;
//Ei[1] = Eip_dir[1] * Ei_p + x_hat[1] * Ei_s;
//Ei[2] = Eip_dir[2] * Ei_p + x_hat[2] * Ei_s;
//std::cout << Ev << std::endl;
//std::cout << Ei << std::endl;
//std::cout << std::endl;
Er[0] = Erp_dir[0] * Er_p + x_hat[0] * Er_s;
Er[1] = Erp_dir[1] * Er_p + x_hat[1] * Er_s;
Er[2] = Erp_dir[2] * Er_p + x_hat[2] * Er_s;
Et[0] = Etp_dir[0] * Et_p + x_hat[0] * Et_s;
Et[1] = Etp_dir[1] * Et_p + x_hat[1] * Et_s;
Et[2] = Etp_dir[2] * Et_p + x_hat[2] * Et_s;
}
//calculate the phase offset based on the plane positions
//T phase_i = plane_position.dot(kv - ki); //compute the phase offset for each plane wave
T phase_r = plane_position.dot(ki - kr);
std::complex<T> phase_t =
plane_position[0] * (ki[0] - kt[0]) +
plane_position[1] * (ki[1] - kt[1]) +
plane_position[2] * (ki[2] - kt[2]);
//Ei = Ei * std::exp(std::complex<T>(0, 1));
Er = Er * std::exp(std::complex<T>(0, 1) * phase_r);
Et = Et * std::exp(std::complex<T>(0, 1) * phase_t);
//Pi = stim::optics::planewave<T>(ki[0], ki[1], ki[2], Ei[0], Ei[1], Ei[2]);
r = stim::optics::planewave<T>(kr[0], kr[1], kr[2], Er[0], Er[1], Er[2]);
t = stim::optics::planewave<T>(kt[0], kt[1], kt[2], Et[0], Et[1], Et[2]);
return 0;
/*TODO: Generate a real vector from the current K vector - this will not address complex k-vectors
vec3< std::complex<T> > k(3);
k[0] = m_k[0];
k[1] = m_k[1];
k[2] = m_k[2];
vec3< std::complex<T> > E(3);
E[0] = m_E[0];// std::complex<T>(m_E[0].real(), m_E[0].imag());
E[1] = m_E[1];// std::complex<T>(m_E[1].real(), m_E[1].imag());
E[2] = m_E[2];// std::complex<T>(m_E[2].real(), m_E[2].imag());
std::complex<T> cOne(1, 0);
std::complex<T> cTwo(2, 0);
T kmag = m_k.norm2();
int facing = plane_face(k, plane_normal); //determine which direction the plane wave is coming in
if(facing == -1){ //if the wave hits the back of the plane, invert the plane and nr
plane_normal = -plane_normal; //flip the plane
nr = cOne / nr; //invert the refractive index (now nr = n0/n1)
}
//use Snell's Law to calculate the transmitted angle
//vec3<T> plane_normal = -P.n();
T cos_theta_i = k.norm().dot(-plane_normal); //compute the cosine of theta_i
T theta_i = acos(cos_theta_i); //compute theta_i
std::complex<T> sin_theta_t = (cOne / nr) * sin(theta_i); //compute the sine of theta_t using Snell's law
std::complex<T> theta_t = asin(sin_theta_t); //compute the cosine of theta_t
//bool tir = false; //flag for total internal reflection
//if(theta_t != theta_t){
// tir = true;
// theta_t = stim::PI / (T)2;
//}
//handle the degenerate case where theta_i is 0 (the plane wave hits head-on)
if(theta_i == 0){
std::complex<T> rp = (cOne - nr) / (cOne + nr); //compute the Fresnel coefficients
std::complex<T> tp = (cOne * cTwo) / (cOne + nr);
vec3<T> kr = -k;
vec3<T> kt = k * nr; //set the k vectors for theta_i = 0
vec3< std::complex<T> > Er = E * rp; //compute the E vectors
vec3< std::complex<T> > Et = E * tp;
T phase_t = plane_position.dot(k - kt); //compute the phase offset
T phase_r = plane_position.dot(k - kr);
//create the plane waves
//r = planewave<T>(kr, Er, phase_r);
//t = planewave<T>(kt, Et, phase_t);
r = planewave(kr[0], kr[1], kr[2], Er[0], Er[1], Er[2]);
t = planewave(kt[0], kt[1], kt[2], Et[0], Et[1], Et[2]);
return;
}
//compute the Fresnel coefficients
T rp, rs, tp, ts;
rp = tan(theta_t - theta_i) / tan(theta_t + theta_i);
rs = sin(theta_t - theta_i) / sin(theta_t + theta_i);
//if (tir) {
// tp = ts = 0;
//}
//else
{
tp = ( 2 * sin(theta_t) * cos(theta_i) ) / ( sin(theta_t + theta_i) * cos(theta_t - theta_i) );
ts = ( 2 * sin(theta_t) * cos(theta_i) ) / sin(theta_t + theta_i);
}
//compute the coordinate space for the plane of incidence
vec3<T> z_hat = -plane_normal;
vec3<T> y_hat = plane_parallel(k, plane_normal).norm();
vec3<T> x_hat = y_hat.cross(z_hat).norm();
//compute the k vectors for r and t
vec3<T> kr, kt;
kr = ( y_hat * sin(theta_i) - z_hat * cos(theta_i) ) * kmag;
kt = ( y_hat * sin(theta_t) + z_hat * cos(theta_t) ) * kmag * nr;
//compute the magnitude of the p- and s-polarized components of the incident E vector
std::complex<T> Ei_s = E.dot(x_hat);
//int sign = sgn(E0.dot(y_hat));
vec3< std::complex<T> > cx_hat = x_hat;
std::complex<T> Ei_p = (E - cx_hat * Ei_s).len();// *(T)sign;
//compute the magnitude of the p- and s-polarized components of the reflected E vector
std::complex<T> Er_s = Ei_s * rs;
std::complex<T> Er_p = Ei_p * rp;
//compute the magnitude of the p- and s-polarized components of the transmitted E vector
std::complex<T> Et_s = Ei_s * ts;
std::complex<T> Et_p = Ei_p * tp;
//compute the reflected E vector
vec3< std::complex<T> > Er = vec3< std::complex<T> >(y_hat * cos(theta_i) + z_hat * sin(theta_i)) * Er_p + cx_hat * Er_s;
//compute the transmitted E vector
vec3< std::complex<T> > Et = vec3< std::complex<T> >(y_hat * cos(theta_t) - z_hat * sin(theta_t)) * Et_p + cx_hat * Et_s;
T phase_t = plane_position.dot(k - kt);
T phase_r = plane_position.dot(k - kr);
//create the plane waves
//r.m_k = kr;
//r.m_E = Er * exp( complex<T>(0, phase_r) );
//t.m_k = kt;
//t.m_E = Et * exp( complex<T>(0, phase_t) );
r = planewave(kr[0], kr[1], kr[2], Er[0], Er[1], Er[2]);
t = planewave(kt[0], kt[1], kt[2], Et[0], Et[1], Et[2]);*/
}
std::string str()
{
std::stringstream ss;
ss << "k: " << m_k << std::endl;
ss << "E: " << m_E << std::endl;
return ss.str();
}
}; //end planewave class
} //end namespace optics
} //end namespace stim
template <typename T>
std::ostream& operator<<(std::ostream& os, stim::optics::planewave<T> p)
{
os<<p.str();
return os;
}
#endif