Cube  Diff

			int stepg = fast_f2nat(g / (float)steps);
			int b = light.attr4 << PRECBITS;
			int stepb = fast_f2nat(b / (float)steps);
			g /= lightscale;
			stepg /= lightscale;
			b /= lightscale;
			stepb /= lightscale;
			for (int i = 0; i < steps; i++) {

				struct sqr *s = S(x >> PRECBITS, y >> PRECBITS);
				int tl = (l >> PRECBITS) + s->r;
				s->r = tl > 255 ? 255 : tl;
				tl = (g >> PRECBITS) + s->g;
				s->g = tl > 255 ? 255 : tl;
				tl = (b >> PRECBITS) + s->b;
				s->b = tl > 255 ? 255 : tl;

			int dimness = rnd((255 - light.attr2) / 16 + 1);
			x += stepx * dimness;
			y += stepy * dimness;

			if (OUTBORD(x >> PRECBITS, y >> PRECBITS))
				return;

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

				struct sqr *s = S(x >> PRECBITS, y >> PRECBITS);
				int tl = (l >> PRECBITS) + s->r;
				s->r = s->g = s->b = tl > 255 ? 255 : tl;
				if (SOLID(s))
					return;
				x += stepx;
				y += stepy;
				l -= stepl;
				stepl -= 25;
			}
		}
	} else // the old (white) light code, here for the few people with old
	       // video cards that don't support overbright
	{
		for (int i = 0; i < steps; i++) {

			struct sqr *s = S(x >> PRECBITS, y >> PRECBITS);
			int light = l >> PRECBITS;
			if (light > s->r)
				s->r = s->g = s->b = (uchar)light;
			if (SOLID(s))
				return;
			x += stepx;

	rndtime();
}

// median filter, smooths out random noise in light and makes it more mipable
void
postlightarea(const struct block *a)
{
	// assumes area not on edge of world

	for (int x = 0; x < a->xs; x++)
		for (int y = 0; y < a->ys; y++) {
			struct sqr *s = S(x + a->x, y + a->y);
#define median(m)                                                            \
	s->m =                                                               \
	    (s->m * 2 + SW(s, 1, 0)->m * 2 + SW(s, 0, 1)->m * 2 +            \
	        SW(s, -1, 0)->m * 2 + SW(s, 0, -1)->m * 2 + SW(s, 1, 1)->m + \
	        SW(s, 1, -1)->m + SW(s, -1, 1)->m + SW(s, -1, -1)->m) /      \
	    14; // median is 4/2/1 instead
			median(r);
			median(g);
			median(b);
		}

	remip(a, 0);
}

void
calclight()
{
	for (int x = 0; x < ssize; x++) {

		for (int y = 0; y < ssize; y++) {
			struct sqr *s = S(x, y);
			s->r = s->g = s->b = 10;
		}
	}

	for (Entity *e in ents)
		if (e.type == LIGHT)
			calclightsource(e);

	struct block b = { 1, 1, ssize - 2, ssize - 2 };