#pragma once

#pragma once

#ifndef __INTELLISENSE__
#ifndef KERNEL_ARGS
#define KERNEL_ARGS(blk,thrdsz) <<<blk,thrdsz>>>
#endif
#else
#define KERNEL_ARGS(blk,thrdsz)
#define __CUDACC__
#include <device_functions.h>
#endif

#include <cuda.h>
#include <cuda_runtime.h>

#define GLM_FORCE_CUDA
#include <glm/glm.hpp>

__device__ constexpr float PI = 3.141592654;
__device__ constexpr float HALFPI = 0.5*PI;
__device__ constexpr float TAU = 2.0*PI;
__device__ constexpr float PI_RECR = 1.0/PI;

__device__
inline glm::vec2 to_sphcoord(glm::vec3 const& vec)
{
return glm::vec2(
atan2f(-vec.y, -vec.x) + PI,
acosf(vec.z)
);
}

__device__
inline glm::vec3 from_sphcoord(float const& phi, float const& theta)
{
return glm::vec3(
__sinf(theta) * __cosf(phi),
__sinf(theta) * __sinf(phi),
__cosf(theta));
}

__device__
inline glm::vec3 from_sphcoord(float const& phi, float const& cosTheta, float const& sinTheta)
{
return glm::vec3(
sinTheta * __cosf(phi),
sinTheta * __sinf(phi),
cosTheta);
}

__device__
inline glm::vec3 angleToBasis(glm::mat3 const& normalOrthBasis, float const& phi, float const& theta)
{
// angle relative to (N1, N2, N) basis is (sin(phi)cos(theta), sin(phi)sin(theta), cos(phi)).
// perform a change of basis

glm::vec3 base_vec = from_sphcoord(phi, theta);

// representation of the matrix

// return M*base_vec;
// M is the matrix
// \begin{pmatrix}
// -\sin(\phi) & \cos(\theta)\cos(\phi) & \sin(\theta)\cos(\phi) \\
// \cos(\phi) & \cos(\theta)\sin(\phi) & \sin(\theta)\sin(\phi) \\
// 0 & -\sin(\theta) & \cos(\theta)
// \end{pmatrix}

// ( N1 N2 N) column
return normalOrthBasis * base_vec;
}

struct Vec3Utility
{
__device__ static glm::vec3 init()
{
return glm::vec3(0.0f);
}

__device__ static float abs2(glm::vec3 v)
{
return v.x * v.x + v.y * v.y + v.z * v.z;
}
};