Cub3d

Raycating project

To execute this project, clone the public repository, and inside the folder execute, the next bash command:

make && ./Cub3d maps/map_std.cub

Resources
- In order to develope this project we need to use the minilibx library, below all the explanations and function prototypes:
MiniLibX

https://harm-smits.github.io/42docs/libs/minilibx

How to manipulate colors in C using minilibX

Code examples

/* 
The next three functions return each r g b color individually
*/
int	get_r(int trgb)
{
	return ((trgb >> 16) & 0xFF);
}

int	get_g(int trgb)
{
	return ((trgb >> 8) & 0xFF);
}

int	get_b(int trgb)
{
	return (trgb & 0xFF);
}

/* 
return the int representation of rgb 
 */
int rgb_to_int(int r, int g, int b)
{
	return ((r<<16) + (g<<8) + b);
}

/* 
add shadow to any number by modifying each r g b value
*/
int	add_shadow(int rgb)
{
    int r;
    int g;
    int b;

    r = get_r(rgb);
    b = get_g(rgb);
    g = get_b(rgb);
    return (rgb_to_int(r * 0.5, g * 0.5 , b * 0.5));
}

Result applying add_shade to red

Resources

Colors

Project developement

Cub3d raycasting

This project was made with the colaboration of Elsruora who did the parsing part**,** the library used to create this project is called minilibx is provided by school 42, you can find the reference above.

To understand this project and find all the tecniques used to modelate a raycasting, follow the next video series.
Video

Make Your Own Raycaster Part 1

If you want to know to how to draw a line to representate the rays, in C, using minilibx library, see below code

Code

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   draw_line.c                                        :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: jvalenci <jvalenci@student.42.fr>          +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2022/07/16 10:32:44 by jvalenci          #+#    #+#             */
/*   Updated: 2022/09/24 13:08:52 by jvalenci         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "../../includes/cub3d.h"

void	plot_line_low(t_map *m, float *xy0, float *xy1)
{
	m->l->dx = xy1[0] - xy0[0];
	m->l->dy = xy1[1] - xy0[1];
	m->l->yi = 1;
	if (m->l->dy < 0)
	{
		m->l->yi = -1;
		m->l->dy *= -1;
	}
	m->l->d = (2 * m->l->dy) - m->l->dx;
	m->l->x = xy0[0];
	m->l->y = xy0[1];
	while (m->l->x < xy1[0])
	{
		my_mlx_pixel_put(m->s_img[0], m->l->x, m->l->y, \
				choose_color(m, m->t->wall_code));
		if (m->l->d > 0)
		{
			m->l->y += m->l->yi;
			m->l->d += (2 * (m->l->dy - m->l->dx));
		}
		else
			m->l->d += (2 * m->l->dy);
		m->l->x++;
	}
}

void	plot_line_hight(t_map *m, float *xy0, float *xy1)
{
	m->l->dx = xy1[0] - xy0[0];
	m->l->dy = xy1[1] - xy0[1];
	m->l->xi = 1;
	if (m->l->dx < 0)
	{
		m->l->xi = -1;
		m->l->dx *= -1;
	}
	m->l->d = (2 * m->l->dx) - m->l->dy;
	m->l->y = xy0[1];
	m->l->x = xy0[0];
	while (m->l->y < xy1[1])
	{
				// choose_color(m, m->t->wall_code));
        my_mlx_pixel_put(m->s_img[0], m->l->x, m->l->y, \
                choose_color(m, m->t->wall_code));
		if (m->l->d > 0)
		{
			m->l->x += m->l->xi;
			m->l->d += (2 * (m->l->dx - m->l->dy));
		}
		else
			m->l->d += (2 * m->l->dx);
		m->l->y++;
	}
}

/**
   @brief Bresenham's line algorithm is a line drawing algorithm that determines
		   the points of an n-dimensional raster that should be selected in order
		   to form a close approximation to a straight line between two points.
		   It is commonly used to draw line primitives in a bitmap image

   --->    https://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm
*/
void	plot_line(t_map *m, float x0, float y0)
{
	float	xy0[2];

	xy0[0] = x0;
	xy0[1] = y0;
	if (m->height <= 448 && m->width <= 1024)
	{
		if (abs((int)m->l->pdxy[1] - (int)xy0[1]) < \
				abs((int)m->l->pdxy[0] - (int)xy0[0]))
		{
			if (xy0[0] > m->l->pdxy[0])
				plot_line_low(m, m->l->pdxy, xy0);
			else
				plot_line_low(m, xy0, m->l->pdxy);
		}
		else
		{
			if (xy0[1] > m->l->pdxy[1])
				plot_line_hight(m, m->l->pdxy, xy0);
			else
				plot_line_hight(m, xy0, m->l->pdxy);
		}
	}
}

Alexvc23/Cub3d

Cub3d

If you want to know to how to draw a line to representate the rays, in C, using minilibx library, see below code