Just a simple maze generator

gistfile1.cpp

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

typedef struct {
	unsigned int x;
	unsigned int y;
	unsigned char direction;
} Coordinate;

class Dungeon {
	unsigned int _width;
	unsigned int _height;
	unsigned char *_data;

public:
	void generate(unsigned int, unsigned int);
	void write(const char*);
};



#define QUEUE_SIZE 1024

// Cell has been marked => Can't be a candidate anymore.
#define CELL_MARKED 1
#define CELL_FLOOR 128

void Dungeon::generate(unsigned int w, unsigned int h) {
	int oX[4] = { -1,  0, 1, 0 };
	int oY[4] = {  0, -1, 0, 1 };

	Coordinate *queue = new Coordinate[w*h];
	unsigned int load = 0;
	unsigned char *d = new unsigned char[w*h];

	memset(d, 0, sizeof(char)*w*h);

	load = 4;
	queue[0].x = rand() % (w / 2) * 2;
	queue[0].y = rand() % (h / 2) * 2;
	queue[0].direction = 0;

	queue[1].x = queue[0].x;
	queue[1].y = queue[0].y;
	queue[1].direction = 1;

	queue[2].x = queue[0].x;
	queue[2].y = queue[0].y;
	queue[2].direction = 2;

	queue[3].x = queue[0].x;
	queue[3].y = queue[0].y;
	queue[3].direction = 3;

	// As long as there's a wall in the list.
	while(load != 0) {
		unsigned int candidate = rand()%load;
		Coordinate *c = queue + candidate;
		unsigned int x = c->x;
		unsigned int y = c->y;
		unsigned char dir = c->direction;
		unsigned int pos = (y * w) + x;
		// First, remove from the queue.
		--load;
		memcpy(c, queue + load, sizeof(Coordinate));

		*(d + pos) = CELL_FLOOR;

		// Get the direction.
		unsigned int tx = x + oX[dir]*2;
		unsigned int ty = y + oY[dir]*2;
		unsigned int tpos = (ty * w) + (tx);

		if(!((tx < 0) || (tx >= w) || (ty < 0) || (ty >= h))) {
			unsigned char *dest = d + tpos;
			if(((*dest) & CELL_FLOOR) == 0) {
				// It's ok ! Let's propagate by creating candidates.
				// We don't care about loop back as this cell is marked.
				d[(x + oX[dir]) + ((y + oY[dir]) * w)] = CELL_FLOOR;
				d[(x + (oX[dir]*2)) + ((y + (oY[dir]*2)) * w)] = CELL_FLOOR;
				Coordinate *insert = queue + load;
				for(int i = 0; i < 4; ++i) {
					insert[i].x = tx;
					insert[i].y = ty;
					insert[i].direction = i;
				}
				load += 4;
			}
		}
	}

	delete []queue;
	_width = w;
	_height = h;
	_data = d;
}

void Dungeon::write(const char* filename)
{
	FILE *out;
	printf( "Open !\n" );
	out = fopen(filename, "wb");

	printf("Prepare !\n");
	fprintf(out, "P5\n#\n%d %d\n255\n", _width, _height);
	printf("Write\n");
	fwrite(_data, 1, _width*_height, out);
	printf("Close\n");
	fclose(out);
	printf("Done\n");
}

int main()
{
	Dungeon donj;

	donj.generate(32, 32);

	donj.write("maze.pgm");

	return 0;
}

I'm gonna puke. This is awful ...