maze.c

#include "stdafx.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#define SIDE 128
#define PATH_LEN 10
#define MIN_PATH_LEN 8

char grid[SIDE * SIDE];
char x = 0;
char y = 0;

void direction_calc(int direction, int *x_d, int *y_d) {
	switch (direction) {
	case 0:
		*x_d = 1;
		*y_d = 0;
		return;
	case 1:
		*x_d = -1;
		*y_d = 0;
		return;
	case 2:
		*x_d = 0;
		*y_d = 1;
		return;
	case 3:
		*x_d = 0;
		*y_d = -1;
		return;
	}
}

void set_grid(char x, char y) {
	if (x < 0 | y < 0)
		return;

	if (x >= SIDE | y >= SIDE)
		return;

	grid[x * SIDE + y] = 0;
}

int get_grid(char x, char y) {
	if (x < 0 | y < 0)
		return 0;

	if (x >= SIDE | y >= SIDE)
		return 0;

	return grid[x * SIDE + y];
}

void set_grid_alt(char x, char y, int dir) {
	//Make sure that the lines don't cross over something else
	int x_dir = 0;
	int y_dir = 0;
	direction_calc(dir, &x_dir, &y_dir);

	if (x_dir == 0) {
		if (get_grid(x - 1, y) == 0)
			return;

		if (get_grid(x + 1, y) == 0)
			return;

		set_grid(x, y);
	}
	else if (y_dir == 0) {
		if (get_grid(x, y - 1) == 0)
			return;

		if (get_grid(x, y + 1) == 0)
			return;

		set_grid(x, y);
	}
}

int draw_path(char len, int direction) {
	int x_dir = 0;
	int y_dir = 0;
	direction_calc(direction, &x_dir, &y_dir);

	for (int i = 0; i < len; i++) {
		set_grid(x, y);

		x += x_dir;
		y += y_dir;

		if (x < 0)
			x = 0;

		if (x >= SIDE)
			x = SIDE - 1;

		if (y < 0)
			y = 0;

		if (y >= SIDE)
			y = SIDE - 1;
	}

	return 0;
}

int draw_path_alt(char len, int direction) {
	int x_dir = 0;
	int y_dir = 0;
	direction_calc(direction, &x_dir, &y_dir);

	for (int i = 0; i < len; i++) {

		if (i == 0)set_grid(x, y);
		else set_grid_alt(x, y, direction);

		x += x_dir;
		y += y_dir;

		if (x < 0)
			x = 0;

		if (x >= SIDE)
			x = SIDE - 1;

		if (y < 0)
			y = 0;

		if (y >= SIDE)
			y = SIDE - 1;
	}

	return 0;
}

void draw_grid() {
	for (int i = 0; i < SIDE; i++) {
		for (int j = 0; j < SIDE; j++) {


			switch (grid[i * SIDE + j]) {
			case 0:
				printf(" ");
				break;
			case 1:
				printf("%c", 219);
				break;
			case 2:
				printf("S");
				break;
			case 3:
				printf("E");
				break;
			}
		}
		printf("\r\n");
	}
	printf("\r\n");
}

int main(int argc, char *argv[]) {

	if(argc >= 2)srand(atoi(argv[1]));
	else srand(time(NULL));

	memset(grid, 1, SIDE * SIDE);

	//pick a starting location
	x = 0;
	y = rand() % SIDE;
	int start_dir = 0;
	int len = rand() % PATH_LEN;
	if (len < MIN_PATH_LEN)len = MIN_PATH_LEN;

	int orig_x = x;
	int orig_y = y;

	while (x < SIDE - 1) {
		draw_path((char)len, start_dir);

		len = rand() % PATH_LEN;
		if (len < MIN_PATH_LEN)len = MIN_PATH_LEN;

		if (start_dir == 0 | start_dir == 1)
			start_dir = rand() % 2 + 2;
		else
			start_dir = rand() % 2;

		if (start_dir & 1)
		{
			if (x == 0 | y == 0)
				start_dir = (start_dir & 2);
		}
		else {
			if (x == SIDE | y == SIDE)
				start_dir = start_dir | 1;
		}
	}

	int end_x = x;
	int end_y = y;

	for (int j = 0; j < 20; j++) {
		x = rand() % SIDE;
		y = rand() % SIDE;
		for (int i = 0; i < 5; i++) {

			start_dir = rand() % 4;
			len = rand() % PATH_LEN;
			if (len < MIN_PATH_LEN)len = MIN_PATH_LEN;

			draw_path_alt(len, start_dir);

			if (start_dir & 1)
			{
				if (x == 0 | y == 0)
					start_dir = (start_dir & 2);
			}
			else {
				if (x == SIDE | y == SIDE)
					start_dir = start_dir | 1;
			}
		}
	}


	grid[end_x * SIDE + end_y] = 3;
	grid[orig_x * SIDE + orig_y] = 2;

	draw_grid();

	while (true)
		;
}