local void walktree(nodeptr *aptr, nodeptr *nptr, cellptr cptr, cellptr bptr,
nodeptr p, real psize, vector pmid)
{
nodeptr *np, *ap, q;
int actsafe;
matrix trQM;
if (Update(p)) { // new forces needed in node?
np = nptr; // start new active list
actsafe = actmax - NSUB; // leave room for NSUB more
for (ap = aptr; ap < nptr; ap++) { // loop over active nodes
if (Type(*ap) == CELL) { // is this node a cell?
if (accept(*ap, psize, pmid)) { // does it pass the test?
if (Mass(*ap) > 0.0) { // and contribute to field?
Mass(cptr) = Mass(*ap); // copy to interaction list
SETV(Pos(cptr), Pos(*ap));
#if defined(SOFTCORR)
TRACEM(Trace(cptr), Quad(*ap)); // save trace in copy
SETMI(trQM);
MULMS(trQM, trQM, Trace(cptr)/3);
SUBM(Quad(cptr), Quad(*ap), trQM); // store traceless moment
#else
SETM(Quad(cptr), Quad(*ap)); // copy traceless moment
#endif
cptr++; // and bump cell array ptr
}
} else { // this cell fails the test
if (np - active >= actsafe) // make sure list has room
fatal("%s.walktree: active list overflow\n", getprog());
for (q = More(*ap); q != Next(*ap); q = Next(q))
// loop over all subcells
*np++= q; // put them on active list
}
} else // else this node is a body
if (*ap != p && Mass(*ap) > 0.0) { // not self-interaction?
--bptr; // bump body array ptr
Mass(bptr) = Mass(*ap); // and copy data to array
SETV(Pos(bptr), Pos(*ap));
}
}
acttot = MAX(acttot, np - active); // keep track of max active
if (np != nptr) { // if new actives were added
walksub(nptr, np, cptr, bptr, p, psize, pmid);
// then visit next level
} else { // else no actives left
if (Type(p) != BODY) // make sure we got a body
fatal("%s.walktree: recursion terminated with cell\n"
" p = 0x%x psize = %.8f Mass(p) = %g\n"
" pmid = (%.8f,%.8f,%.8f)\n Pos(p) = (%.8f,%.8f,%.8f)\n",
getprog(), (int) p, psize, Mass(p),
pmid[0], pmid[1], pmid[2], Pos(p)[0], Pos(p)[1], Pos(p)[2]);
gravsum((bodyptr) p, cptr, bptr); // sum force on this body
}
}
}
local void walkgrav(nodeptr *aptr, nodeptr *nptr, cellptr cptr, cellptr bptr,
nodeptr p, real psize, vector pmid)
{
nodeptr *np, *ap, q;
int actsafe;
if (Update(p)) { /* are new forces needed? */
np = nptr; /* start new active list */
actsafe = actlen - NSUB; /* leave room for NSUB more */
for (ap = aptr; ap < nptr; ap++) /* loop over active nodes */
if (Cell(*ap)) { /* is this node a cell? */
if (accept(*ap, psize, pmid)) { /* does it pass the test? */
Mass(cptr) = Mass(*ap); /* copy to interaction list */
SETV(Pos(cptr), Pos(*ap));
SETM(Quad(cptr), Quad(*ap));
cptr++; /* and bump cell array ptr */
} else { /* else it fails the test */
if (np - active >= actsafe) /* check list has room */
error("walkgrav: active list overflow\n");
for (q = More(*ap); q != Next(*ap); q = Next(q))
/* loop over all subcells */
*np++= q; /* put on new active list */
}
} else /* else this node is a body */
if (*ap != p) { /* if not self-interaction */
--bptr; /* bump body array ptr */
Mass(bptr) = Mass(*ap); /* and copy data to array */
SETV(Pos(bptr), Pos(*ap));
}
actmax = MAX(actmax, np - active); /* keep track of max active */
if (np != nptr) /* if new actives listed */
walksub(nptr, np, cptr, bptr, p, psize, pmid);
/* then visit next level */
else { /* else no actives left, so */
if (! Body(p)) /* must have found a body */
error("walkgrav: recursion terminated with cell\n");
gravsum((bodyptr) p, cptr, bptr); /* sum force on the body */
}
}
}
