/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_detect.c                                        :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: rbousset <marvin@42.fr>                    +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2020/02/14 17:22:11 by rbousset          #+#    #+#             */
/*   Updated: 2020/02/14 17:23:42 by rbousset         ###   ########lyon.fr   */
/*                                                                            */
/* ************************************************************************** */

#include <libft.h>
#include <cub3d.h>
#include <math.h>

static void
	ft_detection_init_y(t_cub *cl)
{
	cl.rlist.y_delta_dist = sqrt(1 + (cl.rlist.x_ray_dir *
		cl.rlist.x_ray_dir) / (cl.rlist.y_ray_dir *
		cl.rlist.y_ray_dir));
	if (cl.rlist.y_ray_dir < 0)
	{
		cl.mlist.y_step = -1;
		cl.rlist.y_side_dist = (cl.rlist.y_ray_pos -
			cl.rlist.sqy) * cl.rlist.y_delta_dist;
	}
	else
	{
		cl.mlist.y_step = 1;
		cl.rlist.y_side_dist = (cl.rlist.sqy + 1.0 -
			cl.rlist.y_ray_pos) * cl.rlist.y_delta_dist;
	}
}

static void
	ft_detection_init_x(t_cub *cl)
{
	cl.rlist.x_delta_dist = sqrt(1 + (cl.rlist.y_ray_dir *
		cl.rlist.y_ray_dir) / (cl.rlist.x_ray_dir *
		cl.rlist.x_ray_dir));
	if (cl.rlist.x_ray_dir < 0)
	{
		cl.mlist.x_step = -1;
		cl.rlist.x_side_dist = (cl.rlist.x_ray_pos -
			cl.rlist.sqx) * cl.rlist.x_delta_dist;
	}
	else
	{
		cl.mlist.x_step = 1;
		cl.rlist.x_side_dist = (cl.rlist.sqx + 1.0 -
			cl.rlist.x_ray_pos) * cl.rlist.x_delta_dist;
	}
}

void
	ft_detect(t_cub *cl)
{
	ft_detection_init_x(cl);
	ft_detection_init_y(cl);
	cl.rlist.hit = 0;
	while (cl.rlist.hit == 0)
	{
		if (cl.rlist.x_side_dist < cl.rlist.y_side_dist)
		{
			cl.rlist.x_side_dist += cl.rlist.x_delta_dist;
			cl.rlist.sqx += cl.mlist.x_step;
			cl.rlist.side = 0;
		}
		else
		{
			cl.rlist.y_side_dist += cl.rlist.y_delta_dist;
			cl.rlist.sqy += cl.mlist.y_step;
			cl.rlist.side = 1;
		}
		if (cl.mlist.map[cl.rlist.sqx][cl.rlist.sqy] == '1' ||
			cl.mlist.map[cl.rlist.sqx][cl.rlist.sqy] == 'L')
			cl.rlist.hit = 1;
	}
}