-void WarpZone_RefSys_Add(entity me, entity wz);
-void WarpZone_RefSys_AddIncrementally(entity me, entity ref);
-void WarpZone_RefSys_BeginAddingIncrementally(entity me, entity ref);
-vector WarpZone_RefSys_TransformOrigin(entity from, entity to, vector org);
-vector WarpZone_RefSys_TransformVelocity(entity from, entity to, vector vel);
-vector WarpZone_RefSys_TransformAngles(entity from, entity to, vector ang);
-vector WarpZone_RefSys_TransformVAngles(entity from, entity to, vector ang);
-entity WarpZone_RefSys_SpawnSameRefSys(entity me);
+void WarpZone_RefSys_Clear(entity me); // R := id
+void WarpZone_RefSys_Add(entity me, entity wz); // me.R := wz me.R
+void WarpZone_RefSys_AddInverse(entity me, entity wz); // me.R := wz^-1 me.R
+void WarpZone_RefSys_AddTransform(entity me, vector t, vector s); // me.R := [t s] me.R
+void WarpZone_RefSys_AddInverseTransform(entity me, vector t, vector s); // me.R := [t s]^-1 me.R
+
+// makes this reference system track ref's changes
+// NOTE: this is ONLY sensible if WarpZone_RefSys_Add is no longer called on "me" while doing this
+// To achieve this, make sure no touch events on warpzone are raised by this entity
+// or set a movetype that causes no warpzoning (e.g. MOVETYPE_NONE, MOVETYPE_FOLLOW)
+void WarpZone_RefSys_AddIncrementally(entity me, entity ref); // me.R := ref.R me.Rref^-1 me.R; me.Rref := ref.R
+void WarpZone_RefSys_BeginAddingIncrementally(entity me, entity ref); // me.Rref := ref.R
+
+vector WarpZone_RefSys_TransformOrigin(entity from, entity to, vector org); // return to.R from.R^-1 org
+vector WarpZone_RefSys_TransformVelocity(entity from, entity to, vector vel); // return to.R from.R^-1 vel
+vector WarpZone_RefSys_TransformAngles(entity from, entity to, vector ang); // return to.R from.R^-1 ang
+vector WarpZone_RefSys_TransformVAngles(entity from, entity to, vector ang); // return to.R from.R^-1 ang
+void WarpZone_RefSys_Copy(entity me, entity from); // to.R := from.R
+entity WarpZone_RefSys_SpawnSameRefSys(entity me); // spawn().R = me.R
+
+#ifndef BITCLR
+# define BITCLR(a,b) ((a) - ((a) & (b)))
+#endif
+#ifndef BITSET
+# define BITSET(a,b) ((a) | (b))
+#endif
+#ifndef BITXOR
+# define BITXOR(a,b) (((a) | (b)) - ((a) & (b)))
+#endif
+#ifndef BITCLR_ASSIGN
+# define BITCLR_ASSIGN(a,b) ((a) = (a) - ((a) & (b)))
+#endif
+#ifndef BITSET_ASSIGN
+# define BITSET_ASSIGN(a,b) ((a) |= (b))
+#endif
+#ifndef BITXOR_ASSIGN
+# define BITXOR_ASSIGN(a,b) ((a) = ((a) | (b)) - ((a) & (b)))
+#endif