42_cube3D/game/dda.c
2023-05-03 17:48:36 +02:00

153 lines
3.8 KiB
C

/* ************************************************************************** */
/* */
/* ::: :::::::: */
/* dda.c :+: :+: :+: */
/* +:+ +:+ +:+ */
/* By: erey-bet <marvin@42.fr> +#+ +:+ +#+ */
/* +#+#+#+#+#+ +#+ */
/* Created: 2023/05/02 15:49:00 by erey-bet #+# #+# */
/* Updated: 2023/05/03 17:37:31 by erey-bet ### ########.fr */
/* */
/* ************************************************************************** */
#include "game.h"
double ft_abs(double nb)
{
if (nb < 0)
return (-nb);
return (nb);
}
void init_dda(t_game *game, t_dda *dda)
{
t_ray *ray;
t_ply *ply;
ray = &game->ray;
ply = &game->ply;
dda->map_x = (int)ply->pos_x;
dda->map_y = (int)ply->pos_y;
if (ray->dir_x == 0)
dda->delta_dist_x = 1e30;
else
dda->delta_dist_x = ft_abs(1 / ray->dir_x);
if (ray->dir_y == 0)
dda->delta_dist_y = 1e30;
else
dda->delta_dist_y = ft_abs(1 / ray->dir_y);
dda->step_x = 1;
dda->step_y = 1;
if (ray->dir_x < 0)
{
dda->step_x = -1;
dda->side_dist_x = (ply->pos_x - dda->map_x) * dda->delta_dist_x;
}
else
dda->side_dist_x = (dda->map_x + 1.0 - ply->pos_x) * dda->delta_dist_x;
if (ray->dir_y < 0)
{
dda->step_y = -1;
dda->side_dist_y = (ply->pos_y - dda->map_y) * dda->delta_dist_y;
}
else
dda->side_dist_y = (dda->map_y + 1.0 - ply->pos_y) * dda->delta_dist_y;
dda->hit = 0;
}
void loop_dda(t_game *game, t_dda *dda)
{
while (dda->hit == 0)
{
if (dda->side_dist_x < dda->side_dist_y)
{
dda->side_dist_x += dda->delta_dist_x;
dda->map_x += dda->step_x;
dda->side = 0;
}
else
{
dda->side_dist_y += dda->delta_dist_y;
dda->map_y += dda->step_y;
dda->side = 1;
}
if (dda->map_x >= 0 && dda->map_y >= 0 &&
game->map.map[dda->map_y][dda->map_x] == '1')
dda->hit = 1;
}
}
void ray_dda(t_dda *dda)
{
if(dda->side == 0)
dda->perp_wall_dist = dda->side_dist_x - dda->delta_dist_x;
else
dda->perp_wall_dist = dda->side_dist_y - dda->delta_dist_y;
if (dda->perp_wall_dist == 0)
dda->perp_wall_dist = 1e30;
dda->line_height = (int)(HEIGHT / dda->perp_wall_dist);
dda->draw_start = -(dda->line_height) / 2 + HEIGHT / 2;
if(dda->draw_start < 0)
dda->draw_start = 0;
dda->draw_end = dda->line_height / 2 + HEIGHT / 2;
if(dda->draw_end >= HEIGHT)
dda->draw_end = HEIGHT - 1;
}
unsigned int get_rgba(int r, int g, int b, int a)
{
return (a << 24 | r << 16 | g << 8 | b);
}
void draw_line(t_game *game, t_dda *dda, unsigned int color, int x)
{
int y;
unsigned int white;
white = 0xFFFFFFFF;
y = 0;
while (y < HEIGHT)
{
if (y < dda->draw_start)
{
mlx_put_pixel(game->window, x, y, white);
}
else if (y >= dda->draw_start && y <= dda->draw_end)
{
mlx_put_pixel(game->window, x, y, color);
}
else if (y > dda->draw_end)
{
mlx_put_pixel(game->window, x, y, white);
}
y ++;
}
}
void draw_dda(t_game *game, t_dda *dda, int x)
{
unsigned int color;
if (dda->step_x == -1 && dda->side == 0) // EAST
color = get_rgba(255, 0, 0, 255);
else if (dda->step_x == 1 && dda->side == 0) // WEST
color = get_rgba(0, 255, 0, 255);
else if (dda->step_y == 1 && dda->side == 1) // NORTH
color = get_rgba(0, 0, 255, 255);
else // SOUTH
color = get_rgba(100, 100, 100, 255);
draw_line(game, dda, color, x);
}
void dda(t_game *game, int x)
{
t_dda dda;
init_dda(game, &dda);
loop_dda(game, &dda);
ray_dda(&dda);
draw_dda(game, &dda, x);
}