Cube  Diff

render_seg_new(
    float vx, float vy, float vh, int mip, int x, int y, int xs, int ys)
{
	struct sqr *w = wmip[mip];
	int sz = ssize >> mip;
	int vxx = ((int)vx + (1 << mip) / 2) >> mip;
	int vyy = ((int)vy + (1 << mip) / 2) >> mip;
	int lx =
	    vxx - lodleft; // these mark the rect inside the current rest that
	                   // we want to render using a lower mip level
	// these mark the rect inside the current rest that we want to render
	// using a lower mip level
	int lx = vxx - lodleft;
	int ly = vyy - lodtop;
	int rx = vxx + lodright;
	int ry = vyy + lodbot;

	float fsize = (float)(1 << mip);
	Player *player1 = Player.player1;
	for (int ox = x; ox < xs; ox++) {
		// first collect occlusion information for this block
		for (int oy = y; oy < ys; oy++) {
			SWS(w, ox, oy, sz)->occluded =
			    isoccluded(player1.origin.x, player1.origin.y,
			        (float)(ox << mip), (float)(oy << mip), fsize);
			    (float)(ox << mip), (float)(oy << mip), fsize);
		}
	}

	int pvx = (int)vx >> mip;
	int pvy = (int)vy >> mip;
	if (pvx >= 0 && pvy >= 0 && pvx < sz && pvy < sz) {
		// SWS(w,vxx,vyy,sz)->occluded = 0;

	// loop through the rect 3 times (for floor/ceil/walls seperately, to
	// facilitate dynamic stripify) for each we skip occluded cubes
	// (occlusion at higher mip levels is a big time saver!). during the
	// first loop (ceil) we collect cubes that lie within the lower mip rect
	// and are also deferred, and render them recursively. Anything left
	// (perfect mips and higher lods) we render here.

#define LOOPH                                                          \
	{                                                              \
		for (int xx = x; xx < xs; xx++)                        \
			for (int yy = y; yy < ys; yy++) {              \
				struct sqr *s = SWS(w, xx, yy, sz);    \
				if (s->occluded == 1)                  \
					continue;                      \
				if (s->defer && !s->occluded && mip && \
				    xx >= lx && xx < rx && yy >= ly && \
#define LOOPH								\
	{								\
		for (int xx = x; xx < xs; xx++)				\
			for (int yy = y; yy < ys; yy++) {		\
				struct sqr *s = SWS(w, xx, yy, sz);	\
				if (s->occluded == 1)			\
					continue;			\
				if (s->defer && !s->occluded && mip &&	\
				    xx >= lx && xx < rx && yy >= ly &&	\
				    yy < ry)
#define LOOPD                             \
	struct sqr *t = SWS(s, 1, 0, sz); \
	struct sqr *u = SWS(s, 1, 1, sz); \
#define LOOPD					\
	struct sqr *t = SWS(s, 1, 0, sz);	\
	struct sqr *u = SWS(s, 1, 1, sz);	\
	struct sqr *v = SWS(s, 0, 1, sz);

	LOOPH // ceils
	{
		int start = yy;
		struct sqr *next;
		while (yy < ys - 1 && (next = SWS(w, xx, yy + 1, sz))->defer &&