/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_raycasting.c                                    :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: rbousset <marvin@42.fr>                    +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2020/02/14 17:22:57 by rbousset          #+#    #+#             */
/*   Updated: 2020/02/14 17:23:42 by rbousset         ###   ########lyon.fr   */
/*                                                                            */
/* ************************************************************************** */

#include <cub3d.h>
#include <stdint.h>

static void
	ft_initray(t_cub *cl, uint16_t i)
{
	t_win		*wl;
	t_player	*pl;

	wl = cl->wlist;
	pl = cl->plist;
	pl->cam_x = 2 * i / (float)(wl->x_size) - 1;
	cl->rlist.x_ray_pos = pl->pos_y;
	cl->rlist.y_ray_pos = pl->pos_x;
	cl->rlist.x_ray_dir = pl->dir_x + pl->plane_x *
		pl->cam_x;
	cl->rlist.y_ray_dir = pl->dir_y + pl->plane_y *
		pl->cam_x;
	cl->rlist.sqx = (int16_t)cl->rlist.x_ray_pos;
	cl->rlist.sqy = (int16_t)cl->rlist.y_ray_pos;
	ft_detect(cl);
	if (cl->rlist.side == 0)
		cl->rlist.wall_dist = (cl->rlist.sqx - cl->rlist.x_ray_pos +
		(1 - cl->mlist->x_step) / 2) / cl->rlist.x_ray_dir;
	else
		cl->rlist.wall_dist = (cl->rlist.sqy - cl->rlist.y_ray_pos +
		(1 - cl->mlist->y_step) / 2) / cl->rlist.y_ray_dir;
}

void
	ft_castray(t_cub *cl)
{
	uint16_t	i;
	t_win		*wl;

	i = 0;
	wl = cl->wlist;
	while (i < wl->x_size)
	{
		ft_initray(cl, i);
		cl->rlist.line_h = (int16_t)(wl->y_size / cl->rlist.wall_dist);
		cl->rlist.wall_t = -cl->rlist.line_h / 2 + wl->y_size / 2;
		if (cl->rlist.wall_t < 0)
			cl->rlist.wall_t = 0;
		cl->rlist.wall_b = cl->rlist.line_h / 2 + wl->y_size / 2;
		if (cl->rlist.wall_b >= wl->y_size)
			cl->rlist.wall_b = wl->y_size - 1;
		ft_draw_verline(cl, i, cl->rlist.wall_t - 1, cl->rlist.wall_b);
		i++;
	}
}