1  /* ************************************************************************** */
 2  /*                                                                            */
 3  /*                                                        :::      ::::::::   */
 4  /*   plane.c                                            :+:      :+:    :+:   */
 5  /*                                                    +:+ +:+         +:+     */
 6  /*   By: salee2 <salee2@student.42seoul.kr>         +#+  +:+       +#+        */
 7  /*                                                +#+#+#+#+#+   +#+           */
 8  /*   Created: 2023/05/24 20:22:38 by salee2            #+#    #+#             */
 9  /*   Updated: 2023/05/24 20:22:39 by salee2           ###   ########.fr       */
10  /*                                                                            */
11  /* ************************************************************************** */
12  
13  #include "include/minirt.h"
14  
15  t_plane	*plane_(t_point3 point, t_vec3 normal)
16  {
17  	t_plane	*this;
18  
19  	this = (t_plane *)malloc(sizeof(t_plane));
20  	if (this == NULL)
21  		return (NULL);
22  	this->point = point;
23  	this->normal = normal;
24  	return (this);
25  }
26  
27  t_bool	intersect_ray_plane(t_object *object, t_ray *ray, t_hit *hit)
28  {
29  	double			root;
30  	const t_plane	*plane = object->element;
31  	const t_vec3	p0l0 = sub(plane->point, ray->origin);
32  	const double	numerator = dot(p0l0, plane->normal);
33  	const double	denominator = dot(plane->normal, ray->dir);
34  
35  	if (fabs(denominator) <= EPSILON)
36  		return (FALSE);
37  	root = numerator / denominator;
38  	if (root < hit->t_min || hit->t_max < root)
39  		return (FALSE);
40  	hit->t = root;
41  	hit->t_max = hit->t;
42  	hit->point = ray_at(hit->t, ray);
43  	hit->normal = plane->normal;
44  	if (dot(ray->dir, hit->normal) > 0)
45  		hit->normal = scl_mul(-1, hit->normal);
46  	hit->albedo = object->albedo;
47  	return (TRUE);
48  }