t_point cylinder_inter(t_line line, t_list *list)
{
t_point n_line;
double a;
double b;
double c;
double delta;
t_point p1;
t_point p2;
double t1;
double t2;
n_line = vector_minus(line.pos, list->pos);
a = line.ori.x * line.ori.x + line.ori.y * line.ori.y;
b = 2 * n_line.x * line.ori.x + 2 * n_line.y * line.ori.y;
c = n_line.x * n_line.x + n_line.y * n_line.y \
- list->radius * list->radius;
delta = b * b - 4 * a * c;
if (delta < 0)
return (line.pos);
t1 = (-b + sqrt(delta)) / (2 * a);
t2 = (-b - sqrt(delta)) / (2 * a);
p1 = vector_add_mult(line.pos, t1, line.ori);
p2 = vector_add_mult(line.pos, t2, line.ori);
return (closer_point(line.pos, p1, p2));
}
/*
* Calculate light color
*/
color lightColor(const intersection *inter, const ray *srcRay) {
vec3 v = vector_normalized(vector_float_mul(-1.0f, srcRay->dir));
color cD = BLACK, refCoef = reflectCoef(inter->mat.reflect_coef, inter->normal, srcRay->dir);
// For each light calculate and sum color
for (int k = 0; k < num_lights; ++k) {
vec3 l = vector_minus(lights[k].position, inter->position);
float normL = vector_norm(l);
l = vector_normalized(l);
// Look for object between light source and current intersection
ray objectRay; // Ray from object to light
ray_init(&objectRay, inter->position, l, EPSILON, normL, 0);
float interFound = 0.0f;
for (int i = 0; i < object_count; ++i) {
interFound += interDist(&objectRay, &(scene[i]));
}
if (!interFound) {
vec3 h = vector_normalized(vector_add(l, v));
float sc_nl = clamp(vector_dot(inter->normal, l), 0.0f, 1.0f);
float sc_hn = clamp(vector_dot(h, inter->normal), 0.0f, 1.0f);
cD = vector_add(cD,
vector_vec_mul(lights[k].col,
vector_float_mul(sc_nl,
(vector_add(vector_float_mul(1 / M_PI, inter->mat.kd),
(vector_float_mul(pow(sc_hn, inter->mat.shininess), vector_float_mul(((inter->mat.shininess + 8) / (8 * M_PI)), refCoef))))))));
}
}
return cD;
}
camera init_camera(point3 position, point3 at, vec3 up, float fov, float aspect) {
camera cam;
cam.fov = fov;
cam.aspect = aspect;
cam.position = position;
cam.zdir = vector_normalized(vector_minus(at, position));
cam.xdir = vector_normalized(vector_cross(up, cam.zdir));
cam.ydir = vector_normalized(vector_cross(cam.zdir, cam.xdir));
cam.center = vector_float_mul(1.f / tanf((cam.fov * M_PI / 180.f) * 0.5f), cam.zdir);
return cam;
}
float interDistSphere(const ray *r, const object *obj) {
vec3 ominusc = vector_minus(r->orig, obj->center);
float a = vector_dot(r->dir, r->dir);
float b = 2.0f * vector_dot(r->dir, ominusc);
float c = (vector_dot(ominusc, ominusc) - obj->radius * obj->radius);
float delta = b * b - 4.0f * a * c;
if (delta > 0.0f) {
float sqrtDelta = sqrt(delta);
float t0 = (-b - sqrtDelta) / (2.0f * a), t1 = (-b + sqrtDelta) / (2.0f * a);
return t0 > t1 ? t1 : t0;
}
return -1.0f;
}
/*
* Calculate the intersection between a ray and an object
*/
int intersect(ray *r, const object *obj, intersection *inter) {
float dist = interDist(r, obj);
if (dist != 0.0f) {
switch (obj->type) {
case CYLINDER:
//
break;
case PLANE:
inter->normal = obj->normal;
break;
case SPHERE:
inter->normal = vector_normalized(vector_minus(ray_at(*r, dist), obj->center));
break;
}
inter->position = ray_at(*r, dist);
inter->mat = obj->mat;
return 1; // Intersection found
}
return 0;
}
vec3 vector_reflect(vec3 v, vec3 n) {
return vector_minus(v, vector_float_mul(2.f * vector_dot(n, v), n));
}
