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101 lines
2.9 KiB
101 lines
2.9 KiB
2 years ago
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#ifndef GEOH
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#define GEOH
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#include <cmath>
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#include "ray.h"
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using namespace std;
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struct hit_record {
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float t;
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vec3 p;
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vec3 nv;
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vec3 kd;
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float wr;
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float wt;
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};
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class hitable { //geometry parent class
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public:
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virtual bool hit(const ray &r, float tmin, float tmax, hit_record *rec) const = 0;
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};
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class sphere : public hitable {
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public:
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sphere() {}
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sphere(vec3 c, float r, vec3 _kd = vec3(1.0, 1.0, 1.0), float w_ri = 0.0f, float w_ti = 0.0f) : center(c), radius(r), kd(_kd), w_r(w_ri), w_t(w_ti){};
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bool hit(const ray &r, float tmin, float tmax, hit_record *rec) const;
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vec3 center;
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float radius;
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vec3 kd;
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float w_r; //reflected
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float w_t; //transmitted
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};
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bool sphere::hit(const ray &r, float tmin, float tmax, hit_record *rec) const {
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float a, b, c, t;
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a = dot(r.D, r.D);
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b = 2 * (dot(r.D, (r.O - this->center)));
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c = dot(r.O - this->center, r.O - this->center) - this->radius * this->radius;
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if (((b * b) - (4 * a * c)) > 0) {
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if ((((-b) - sqrt((b * b) - (4 * a * c))) / (2 * a)) > tmin && (((-b) + sqrt((b * b) - (4 * a * c))) / (2 * a)) > tmin) {
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t = min((((-b) - sqrt((b * b) - (4 * a * c))) / (2 * a)), (((-b) + sqrt((b * b) - (4 * a * c))) / (2 * a)));
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} else if ((((-b) - sqrt((b * b) - (4 * a * c))) / (2 * a)) > tmin) {
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t = (((-b) - sqrt((b * b) - (4 * a * c))) / (2 * a));
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} else if ((((-b) + sqrt((b * b) - (4 * a * c))) / (2 * a)) > tmin) {
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t = (((-b) + sqrt((b * b) - (4 * a * c))) / (2 * a));
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} else {
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return false;
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}
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} else {
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return false;
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}
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if (t > tmax || t < tmin) {
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return false;
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}
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if (rec->t > t) {
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rec->t = t;
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rec->p = r.point_at_parameter(t);
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rec->nv = unit_vector(r.point_at_parameter(t) - this->center);
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rec->kd = this->kd;
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rec->wr = this->w_r;
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rec->wt = this->w_t;
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//cout << t << " " << rec->p << " " << rec->nv << endl;
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}
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return true;
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}
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vec3 reflect(const vec3 &d, const vec3 &nv) {
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return d - (2 * dot(d, nv) * nv);
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return vec3(0, 0, 0);
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}
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template <typename T>
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float clamp(T bot, T top, T targ) {
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if (targ > top) {
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return top;
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}
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if (targ < bot) {
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return bot;
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}
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return targ;
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}
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vec3 refract(const vec3 &i, const vec3 &n, float eta) {
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vec3 I = unit_vector(i);
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vec3 N = unit_vector(n);
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//cout << I << " " << N << " " << dot(N, I) << endl;
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eta = 1 / eta;
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if (dot(N, I) > 0) {
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N = -1 * N;
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eta = 1 / eta;
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}
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float k = 1.0f - eta * eta * (1.0 - dot(N, I) * dot(N, I));
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//cout << k << endl;
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if (k < 0.0) {
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return i - (2 * dot(i, n) * n);
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}
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//cout << eta * I - (eta * dot(N, I) + sqrt(k)) * N << endl;
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return eta * I - (eta * dot(N, I) + sqrt(k)) * N;
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}
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#endif
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