Yannis Antoine
128 lines
4.3 KiB
C
128 lines
4.3 KiB
C
/* ************************************************************************** */
|
|
/* */
|
|
/* ::: :::::::: */
|
|
/* parsing_cylinder_utils.c :+: :+: :+: */
|
|
/* +:+ +:+ +:+ */
|
|
/* By: yantoine <yantoine@student.42.fr> +#+ +:+ +#+ */
|
|
/* +#+#+#+#+#+ +#+ */
|
|
/* Created: 2025/02/17 18:54:45 by yantoine #+# #+# */
|
|
/* Updated: 2025/03/05 14:23:21 by yantoine ### ########.fr */
|
|
/* */
|
|
/* ************************************************************************** */
|
|
|
|
#include "miniRT.h"
|
|
|
|
// Initialise les variables de calcul et les
|
|
// coefficients du polynôme d'intersection
|
|
int init_intersection(t_ray ray, t_cylinder cy, t_calc *calc)
|
|
{
|
|
calc->d = ray.dir;
|
|
calc->oc = vec3_sub(ray.origin, cy.center);
|
|
calc->v = cy.axis;
|
|
calc->d_dot_v = vec3_dot(calc->d, calc->v);
|
|
calc->oc_dot_v = vec3_dot(calc->oc, calc->v);
|
|
calc->d_perp = vec3_sub(calc->d, vec3_scale(calc->v, calc->d_dot_v));
|
|
calc->oc_perp = vec3_sub(calc->oc, vec3_scale(calc->v, calc->oc_dot_v));
|
|
calc->a = vec3_dot(calc->d_perp, calc->d_perp);
|
|
calc->b = 2 * vec3_dot(calc->d_perp, calc->oc_perp);
|
|
calc->c = vec3_dot(calc->oc_perp, calc->oc_perp) - cy.radius * cy.radius;
|
|
calc->disc = calc->b * calc->b - 4 * calc->a * calc->c;
|
|
if (calc->disc < 0)
|
|
return (-1);
|
|
calc->sqrt_disc = sqrtf(calc->disc);
|
|
calc->t0 = (-calc->b - calc->sqrt_disc) / (2 * calc->a);
|
|
calc->t1 = (-calc->b + calc->sqrt_disc) / (2 * calc->a);
|
|
return (0);
|
|
}
|
|
|
|
// Calcule l'intersection sur la surface
|
|
//latérale du cylindre
|
|
void compute_side_intersection(t_cylinder cy, t_calc *calc)
|
|
{
|
|
calc->t_side = -1;
|
|
if (calc->t0 > 0.001f)
|
|
{
|
|
calc->y = calc->oc_dot_v + calc->t0 * calc->d_dot_v;
|
|
if (fabs(calc->y) <= cy.height / 2.0f)
|
|
calc->t_side = calc->t0;
|
|
}
|
|
if (calc->t_side < 0 && calc->t1 > 0.001f)
|
|
{
|
|
calc->y = calc->oc_dot_v + calc->t1 * calc->d_dot_v;
|
|
if (fabs(calc->y) <= cy.height / 2.0f)
|
|
calc->t_side = calc->t1;
|
|
}
|
|
}
|
|
|
|
// Calcule l'intersection sur les
|
|
// capuchons supérieur et inférieur
|
|
void compute_cap_intersection(t_ray ray, t_cylinder cy, t_calc *calc)
|
|
{
|
|
calc->t_cap = -1;
|
|
if (fabs(calc->d_dot_v) > 0.001f)
|
|
{
|
|
calc->t_bot = ((-cy.height / 2.0f) - calc->oc_dot_v) / calc->d_dot_v;
|
|
if (calc->t_bot > 0.001f)
|
|
{
|
|
calc->p = vec3_add(ray.origin, vec3_scale(calc->d, calc->t_bot));
|
|
calc->cp = vec3_sub(calc->p, cy.center);
|
|
calc->dist = vec3_length(vec3_sub(calc->cp, vec3_scale(calc->v,
|
|
vec3_dot(calc->cp, calc->v))));
|
|
if (calc->dist <= cy.radius)
|
|
calc->t_cap = calc->t_bot;
|
|
}
|
|
calc->t_top = ((cy.height / 2.0f) - calc->oc_dot_v) / calc->d_dot_v;
|
|
if (calc->t_top > 0.001f)
|
|
{
|
|
calc->p = vec3_add(ray.origin, vec3_scale(calc->d, calc->t_top));
|
|
calc->cp = vec3_sub(calc->p, cy.center);
|
|
calc->dist = vec3_length(vec3_sub(calc->cp, vec3_scale(calc->v,
|
|
vec3_dot(calc->cp, calc->v))));
|
|
if (calc->dist <= cy.radius && (calc->t_cap < 0
|
|
|| calc->t_top < calc->t_cap))
|
|
calc->t_cap = calc->t_top;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Sélectionne l'intersection la plus
|
|
//proche entre la surface latérale et les capuchons
|
|
float select_final_intersection(t_calc *calc)
|
|
{
|
|
if (calc->t_side > 0.001f && calc->t_cap > 0.001f)
|
|
{
|
|
if (calc->t_side < calc->t_cap)
|
|
calc->t_final = calc->t_side;
|
|
else
|
|
calc->t_final = calc->t_cap;
|
|
}
|
|
else if (calc->t_side > 0.001f)
|
|
calc->t_final = calc->t_side;
|
|
else
|
|
calc->t_final = calc->t_cap;
|
|
if (calc->t_final > 0.001f)
|
|
return (calc->t_final);
|
|
return (-1);
|
|
}
|
|
|
|
// Calcule la normale au point d'intersection
|
|
void compute_hit_normal(t_ray ray, t_cylinder cy, t_calc *calc,
|
|
t_vec3 *hitNormal)
|
|
{
|
|
calc->hit_point = vec3_add(ray.origin, vec3_scale(calc->d, calc->t_final));
|
|
calc->cp = vec3_sub(calc->hit_point, cy.center);
|
|
calc->proj = vec3_dot(calc->cp, calc->v);
|
|
if (fabs(calc->proj) < cy.height / 2.0f - 0.001f)
|
|
{
|
|
calc->n = vec3_sub(calc->cp, vec3_scale(calc->v, calc->proj));
|
|
*hitNormal = vec3_normalize(calc->n);
|
|
}
|
|
else
|
|
{
|
|
if (calc->proj > 0)
|
|
*hitNormal = calc->v;
|
|
else
|
|
*hitNormal = vec3_scale(calc->v, -1);
|
|
}
|
|
}
|