display_texture.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   display_texture.c                                  :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: jaemjeon <jaemjeon@student.42seoul.kr>     +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2022/11/02 16:00:27 by jaemjeon          #+#    #+#             */
/*   Updated: 2022/11/13 09:51:10 by jaemjeon         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

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

unsigned int	get_texture_pixel(t_game *game, int idx_x, \
										t_vector2 *wall_line, int cur_idx_y)
{
	t_ray *const	cur_ray = &game->ray_data[idx_x];
	t_img_data		*texture_img;
	t_vector2		ratio_pos_texture;
	int				texture_idx_x;
	int				texture_idx_y;

	texture_img = &game->texture[cur_ray->hit_wall_side].img_data;
	texture_idx_x = game->texture[cur_ray->hit_wall_side].texture_width;
	texture_idx_y = game->texture[cur_ray->hit_wall_side].texture_height;
	ratio_pos_texture.x = cur_ray->hit_texture_point;
	ratio_pos_texture.y = \
				(cur_idx_y - wall_line->x) / (wall_line->y - wall_line->x);
	texture_idx_x *= ratio_pos_texture.x;
	texture_idx_y *= ratio_pos_texture.y;
	return (*(unsigned int *)(texture_img->addr + \
			texture_idx_y * texture_img->line_length + texture_idx_x * \
											(texture_img->bits_per_pixel / 8)));
}

void	put_pixel_wall(t_game *game, int idx_x)
{
	t_img_data *const	view_data = &game->view_data;
	double				gradiant;
	unsigned int		pixel;
	char				*dst;
	int					cur_idx_y;

	gradiant = 0.2 + (0.8 - game->ray_data[idx_x].wall_distance * 0.05);
	set_range_double(&gradiant, 0, 1);
	cur_idx_y = ceil(game->wall_pixel[idx_x].x);
	while (cur_idx_y < game->wall_pixel[idx_x].y)
	{
		dst = view_data->addr + (cur_idx_y * view_data->line_length + \
								idx_x * (view_data->bits_per_pixel / 8));
		pixel = \
			get_texture_pixel(game, idx_x, &game->wall_line[idx_x], cur_idx_y);
		*(unsigned int *)dst = create_trgb(game->player.view_trans, \
	get_r(pixel) * gradiant, get_g(pixel) * gradiant, get_b(pixel) * gradiant);
		cur_idx_y++;
	}
}