Cube  Diff

	    ((n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff) /
	    1073741824.0f;
}

float
smoothednoise(int x, int y, int seed)
{
	float corners =
	    (noise(x - 1, y - 1, seed) + noise(x + 1, y - 1, seed) +
	        noise(x - 1, y + 1, seed) + noise(x + 1, y + 1, seed)) /
	float corners = (noise(x - 1, y - 1, seed) + noise(x + 1, y - 1, seed) +
	    noise(x - 1, y + 1, seed) + noise(x + 1, y + 1, seed)) / 16;
	    16;
	float sides = (noise(x - 1, y, seed) + noise(x + 1, y, seed) +
	                  noise(x, y - 1, seed) + noise(x, y + 1, seed)) /
	    noise(x, y - 1, seed) + noise(x, y + 1, seed)) / 8;
	    8;
	float center = noise(x, y, seed) / 4;
	return corners + sides + center;
}

float
interpolate(float a, float b, float x)
{

	if (!scale)
		scale = 10;
	for (int x = b->x; x <= b->x + b->xs; x++) {
		for (int y = b->y; y <= b->y + b->ys; y++) {
			struct sqr *s = S(x, y);
			if (!SOLID(s) && x != b->x + b->xs && y != b->y + b->ys)
				s->type = FHF;
			s->vdelta =
			    (int)(perlinnoise_2D(x / ((float)scale) + seed,
			              y / ((float)scale) + seed, 1000, 0.01f) *
			s->vdelta = (int)(perlinnoise_2D(
			    x / ((float)scale) + seed,
			    y / ((float)scale) + seed, 1000, 0.01f) * 50 + 25);
			            50 +
			        25);
			if (s->vdelta > 128)
				s->vdelta = 0;
		}
	}
}