backport of PM_RecursiveHullCheck for speedup

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@86 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/world.c b/world.c
index 0519bd85e0f6a80961fc7417ee8264e2a18b020a..5a8d033a468998570d536377a7415ee361a44bce 100644 (file)
--- a/world.c
+++ b/world.c
@@ -567,6 +567,7 @@ SV_RecursiveHullCheck
 
 ==================
 */
+/*
 qboolean SV_RecursiveHullCheck (hull_t *hull, int num, float p1f, float p2f, vec3_t p1, vec3_t p2, trace_t *trace)
 {
        dclipnode_t     *node;
@@ -652,11 +653,12 @@ loc0:
                return false;
        }
 #endif
-       
+
        if (SV_HullPointContents (hull, node->children[side^1], mid) != CONTENTS_SOLID)
 // go past the node
                return SV_RecursiveHullCheck (hull, node->children[side^1], midf, p2f, mid, p2, trace);
        // mid would need to be duplicated during recursion...
+*/
        /*
        {
                p1f = midf;
@@ -665,6 +667,7 @@ loc0:
                goto loc0;
        }
        */
+/*
 
        if (trace->allsolid)
                return false;           // never got out of the solid area
@@ -707,6 +710,138 @@ loc0:
 
        return false;
 }
+*/
+
+// LordHavoc: backported from my optimizations to PM_RecursiveHullCheck in QuakeForge newtree (QW)
+qboolean SV_RecursiveHullCheck (hull_t *hull, int num, float p1f, float p2f, vec3_t p1, vec3_t p2, trace_t *trace)
+{
+       dclipnode_t     *node;
+       mplane_t        *plane;
+       float           t1, t2;
+       float           frac;
+       int                     i;
+       vec3_t          mid;
+       int                     side;
+       float           midf;
+
+       // LordHavoc: a goto!  everyone flee in terror... :)
+loc0:
+// check for empty
+       if (num < 0)
+       {
+               if (num != CONTENTS_SOLID)
+               {
+                       trace->allsolid = false;
+                       if (num == CONTENTS_EMPTY)
+                               trace->inopen = true;
+                       else
+                               trace->inwater = true;
+               }
+               else
+                       trace->startsolid = true;
+               return true;            // empty
+       }
+
+       // LordHavoc: this can be eliminated by validating in the loader...  but Mercury told me not to bother
+       if (num < hull->firstclipnode || num > hull->lastclipnode)
+               Sys_Error ("SV_RecursiveHullCheck: bad node number");
+
+// find the point distances
+       node = hull->clipnodes + num;
+       plane = hull->planes + node->planenum;
+
+       if (plane->type < 3)
+       {
+               t1 = p1[plane->type] - plane->dist;
+               t2 = p2[plane->type] - plane->dist;
+       }
+       else
+       {
+               t1 = DotProduct (plane->normal, p1) - plane->dist;
+               t2 = DotProduct (plane->normal, p2) - plane->dist;
+       }
+
+       // LordHavoc: recursion optimization
+       if (t1 >= 0 && t2 >= 0)
+       {
+               num = node->children[0];
+               goto loc0;
+       }
+       if (t1 < 0 && t2 < 0)
+       {
+               num = node->children[1];
+               goto loc0;
+       }
+
+// put the crosspoint DIST_EPSILON pixels on the near side
+       side = (t1 < 0);
+       if (side)
+               frac = bound(0, (t1 + DIST_EPSILON) / (t1 - t2), 1);
+       else
+               frac = bound(0, (t1 - DIST_EPSILON) / (t1 - t2), 1);
+               
+       midf = p1f + (p2f - p1f)*frac;
+       for (i=0 ; i<3 ; i++)
+               mid[i] = p1[i] + frac*(p2[i] - p1[i]);
+
+// move up to the node
+       if (!SV_RecursiveHullCheck (hull, node->children[side], p1f, midf, p1, mid, trace) )
+               return false;
+
+#ifdef PARANOID
+       if (SV_HullPointContents (pm_hullmodel, mid, node->children[side]) == CONTENTS_SOLID)
+       {
+               Con_Printf ("mid PointInHullSolid\n");
+               return false;
+       }
+#endif
+
+       // LordHavoc: warning to the clumsy, this recursion can not be optimized because mid would need to be duplicated on a stack
+       if (SV_HullPointContents (hull, node->children[side^1], mid) != CONTENTS_SOLID)
+// go past the node
+               return SV_RecursiveHullCheck (hull, node->children[side^1], midf, p2f, mid, p2, trace);
+       
+       if (trace->allsolid)
+               return false;           // never got out of the solid area
+               
+//==================
+// the other side of the node is solid, this is the impact point
+//==================
+       if (!side)
+       {
+               VectorCopy (plane->normal, trace->plane.normal);
+               trace->plane.dist = plane->dist;
+       }
+       else
+       {
+               // LordHavoc: vec3_origin is evil; the compiler can not rely on it being '0 0 0'
+//             VectorSubtract (vec3_origin, plane->normal, trace->plane.normal);
+               trace->plane.normal[0] = -plane->normal[0];
+               trace->plane.normal[1] = -plane->normal[1];
+               trace->plane.normal[2] = -plane->normal[2];
+               trace->plane.dist = -plane->dist;
+       }
+
+       while (SV_HullPointContents (hull, hull->firstclipnode, mid) == CONTENTS_SOLID)
+       { // shouldn't really happen, but does occasionally
+               frac -= 0.1;
+               if (frac < 0)
+               {
+                       trace->fraction = midf;
+                       VectorCopy (mid, trace->endpos);
+                       Con_DPrintf ("backup past 0\n");
+                       return false;
+               }
+               midf = p1f + (p2f - p1f)*frac;
+               for (i=0 ; i<3 ; i++)
+                       mid[i] = p1[i] + frac*(p2[i] - p1[i]);
+       }
+
+       trace->fraction = midf;
+       VectorCopy (mid, trace->endpos);
+
+       return false;
+}
 
 qboolean SV_TestLine (hull_t *hull, int num, vec3_t p1, vec3_t p2)
 {
@@ -761,17 +896,9 @@ loc0:
                if (node->children[side] == CONTENTS_SOLID)
                        return false;
                return SV_TestLine(hull, node->children[!side], mid, p2);
-//             num = node->children[!side];
-//             VectorCopy(mid, p1);
-//             goto loc0;
        }
        else if (SV_TestLine(hull, node->children[side], p1, mid))
-       {
                return SV_TestLine(hull, node->children[!side], mid, p2);
-//             num = node->children[!side];
-//             VectorCopy(mid, p1);
-//             goto loc0;
-       }
        else
                return false;
 }