ref: cd8c8d416b4245458460cfe8e3c00bcb69c3c45b
dir: /world.c/
// world.c -- world query functions
#include <u.h>
#include <libc.h>
#include <stdio.h>
#include "quakedef.h"
/*
entities never clip against themselves, or their owner
line of sight checks trace->crosscontent, but bullets don't
*/
typedef struct
{
vec3_t boxmins, boxmaxs;// enclose the test object along entire move
float *mins, *maxs; // size of the moving object
vec3_t mins2, maxs2; // size when clipping against mosnters
float *start, *end;
trace_t trace;
int type;
edict_t *passedict;
} moveclip_t;
int SV_HullPointContents (hull_t *hull, int num, vec3_t p);
/*
===============================================================================
HULL BOXES
===============================================================================
*/
static hull_t box_hull;
static dclipnode_t box_clipnodes[6];
static mplane_t box_planes[6];
/*
===================
SV_InitBoxHull
Set up the planes and clipnodes so that the six floats of a bounding box
can just be stored out and get a proper hull_t structure.
===================
*/
void SV_InitBoxHull (void)
{
int i;
int side;
box_hull.clipnodes = box_clipnodes;
box_hull.planes = box_planes;
box_hull.firstclipnode = 0;
box_hull.lastclipnode = 5;
for (i=0 ; i<6 ; i++)
{
box_clipnodes[i].planenum = i;
side = i&1;
box_clipnodes[i].children[side] = CONTENTS_EMPTY;
if (i != 5)
box_clipnodes[i].children[side^1] = i + 1;
else
box_clipnodes[i].children[side^1] = CONTENTS_SOLID;
box_planes[i].type = i>>1;
box_planes[i].normal[i>>1] = 1;
}
}
/*
===================
SV_HullForBox
To keep everything totally uniform, bounding boxes are turned into small
BSP trees instead of being compared directly.
===================
*/
hull_t *SV_HullForBox (vec3_t mins, vec3_t maxs)
{
box_planes[0].dist = maxs[0];
box_planes[1].dist = mins[0];
box_planes[2].dist = maxs[1];
box_planes[3].dist = mins[1];
box_planes[4].dist = maxs[2];
box_planes[5].dist = mins[2];
return &box_hull;
}
/*
================
SV_HullForEntity
Returns a hull that can be used for testing or clipping an object of mins/maxs
size.
Offset is filled in to contain the adjustment that must be added to the
testing object's origin to get a point to use with the returned hull.
================
*/
hull_t *SV_HullForEntity (edict_t *ent, vec3_t mins, vec3_t maxs, vec3_t offset)
{
model_t *model;
vec3_t size;
vec3_t hullmins, hullmaxs;
hull_t *hull;
// decide which clipping hull to use, based on the size
if (ent->v.solid == SOLID_BSP)
{ // explicit hulls in the BSP model
if (ent->v.movetype != MOVETYPE_PUSH)
Sys_Error ("SOLID_BSP without MOVETYPE_PUSH");
model = sv.models[ (int)ent->v.modelindex ];
if (!model || model->type != mod_brush)
Sys_Error ("MOVETYPE_PUSH with a non bsp model");
VectorSubtract (maxs, mins, size);
if (size[0] < 3)
hull = &model->hulls[0];
else if (size[0] <= 32)
hull = &model->hulls[1];
else
hull = &model->hulls[2];
// calculate an offset value to center the origin
VectorSubtract (hull->clip_mins, mins, offset);
VectorAdd (offset, ent->v.origin, offset);
}
else
{ // create a temp hull from bounding box sizes
VectorSubtract (ent->v.mins, maxs, hullmins);
VectorSubtract (ent->v.maxs, mins, hullmaxs);
hull = SV_HullForBox (hullmins, hullmaxs);
VectorCopy (ent->v.origin, offset);
}
return hull;
}
/*
===============================================================================
ENTITY AREA CHECKING
===============================================================================
*/
typedef struct areanode_s
{
int axis; // -1 = leaf node
float dist;
struct areanode_s *children[2];
link_t trigger_edicts;
link_t solid_edicts;
} areanode_t;
#define AREA_DEPTH 4
#define AREA_NODES 32
static areanode_t sv_areanodes[AREA_NODES];
static int sv_numareanodes;
/*
===============
SV_CreateAreaNode
===============
*/
areanode_t *SV_CreateAreaNode (int depth, vec3_t mins, vec3_t maxs)
{
areanode_t *anode;
vec3_t size;
vec3_t mins1, maxs1, mins2, maxs2;
anode = &sv_areanodes[sv_numareanodes];
sv_numareanodes++;
ClearLink (&anode->trigger_edicts);
ClearLink (&anode->solid_edicts);
if (depth == AREA_DEPTH)
{
anode->axis = -1;
anode->children[0] = anode->children[1] = nil;
return anode;
}
VectorSubtract (maxs, mins, size);
if (size[0] > size[1])
anode->axis = 0;
else
anode->axis = 1;
anode->dist = 0.5 * (maxs[anode->axis] + mins[anode->axis]);
VectorCopy (mins, mins1);
VectorCopy (mins, mins2);
VectorCopy (maxs, maxs1);
VectorCopy (maxs, maxs2);
maxs1[anode->axis] = mins2[anode->axis] = anode->dist;
anode->children[0] = SV_CreateAreaNode (depth+1, mins2, maxs2);
anode->children[1] = SV_CreateAreaNode (depth+1, mins1, maxs1);
return anode;
}
/*
===============
SV_ClearWorld
===============
*/
void SV_ClearWorld (void)
{
SV_InitBoxHull ();
memset (sv_areanodes, 0, sizeof(sv_areanodes));
sv_numareanodes = 0;
SV_CreateAreaNode (0, sv.worldmodel->mins, sv.worldmodel->maxs);
}
/*
===============
SV_UnlinkEdict
===============
*/
void SV_UnlinkEdict (edict_t *ent)
{
if (!ent->area.prev)
return; // not linked in anywhere
RemoveLink (&ent->area);
ent->area.prev = ent->area.next = nil;
}
/*
====================
SV_TouchLinks
====================
*/
void SV_TouchLinks ( edict_t *ent, areanode_t *node )
{
link_t *l, *next;
edict_t *touch;
int old_self, old_other;
// touch linked edicts
for (l = node->trigger_edicts.next ; l != &node->trigger_edicts ; l = next)
{
next = l->next;
touch = EDICT_FROM_AREA(l);
if (touch == ent)
continue;
if (!touch->v.touch || touch->v.solid != SOLID_TRIGGER)
continue;
if (ent->v.absmin[0] > touch->v.absmax[0]
|| ent->v.absmin[1] > touch->v.absmax[1]
|| ent->v.absmin[2] > touch->v.absmax[2]
|| ent->v.absmax[0] < touch->v.absmin[0]
|| ent->v.absmax[1] < touch->v.absmin[1]
|| ent->v.absmax[2] < touch->v.absmin[2] )
continue;
old_self = pr_global_struct->self;
old_other = pr_global_struct->other;
pr_global_struct->self = EDICT_TO_PROG(touch);
pr_global_struct->other = EDICT_TO_PROG(ent);
pr_global_struct->time = sv.time;
PR_ExecuteProgram (touch->v.touch);
pr_global_struct->self = old_self;
pr_global_struct->other = old_other;
}
// recurse down both sides
if (node->axis == -1)
return;
if ( ent->v.absmax[node->axis] > node->dist )
SV_TouchLinks ( ent, node->children[0] );
if ( ent->v.absmin[node->axis] < node->dist )
SV_TouchLinks ( ent, node->children[1] );
}
/*
===============
SV_FindTouchedLeafs
===============
*/
void SV_FindTouchedLeafs (edict_t *ent, mnode_t *node)
{
mplane_t *splitplane;
mleaf_t *leaf;
int sides;
int leafnum;
if (node->contents == CONTENTS_SOLID)
return;
// add an efrag if the node is a leaf
if ( node->contents < 0)
{
if (ent->num_leafs == MAX_ENT_LEAFS)
return;
leaf = (mleaf_t *)node;
leafnum = leaf - sv.worldmodel->leafs - 1;
ent->leafnums[ent->num_leafs] = leafnum;
ent->num_leafs++;
return;
}
// NODE_MIXED
splitplane = node->plane;
sides = BOX_ON_PLANE_SIDE(ent->v.absmin, ent->v.absmax, splitplane);
// recurse down the contacted sides
if (sides & 1)
SV_FindTouchedLeafs (ent, node->children[0]);
if (sides & 2)
SV_FindTouchedLeafs (ent, node->children[1]);
}
/*
===============
SV_LinkEdict
===============
*/
void SV_LinkEdict (edict_t *ent, qboolean touch_triggers)
{
areanode_t *node;
if (ent->area.prev)
SV_UnlinkEdict (ent); // unlink from old position
if (ent == sv.edicts)
return; // don't add the world
if (ent->free)
return;
// set the abs box
VectorAdd (ent->v.origin, ent->v.mins, ent->v.absmin);
VectorAdd (ent->v.origin, ent->v.maxs, ent->v.absmax);
//
// to make items easier to pick up and allow them to be grabbed off
// of shelves, the abs sizes are expanded
//
if ((int)ent->v.flags & FL_ITEM)
{
ent->v.absmin[0] -= 15;
ent->v.absmin[1] -= 15;
ent->v.absmax[0] += 15;
ent->v.absmax[1] += 15;
}
else
{ // because movement is clipped an epsilon away from an actual edge,
// we must fully check even when bounding boxes don't quite touch
ent->v.absmin[0] -= 1;
ent->v.absmin[1] -= 1;
ent->v.absmin[2] -= 1;
ent->v.absmax[0] += 1;
ent->v.absmax[1] += 1;
ent->v.absmax[2] += 1;
}
// link to PVS leafs
ent->num_leafs = 0;
if (ent->v.modelindex)
SV_FindTouchedLeafs (ent, sv.worldmodel->nodes);
if (ent->v.solid == SOLID_NOT)
return;
// find the first node that the ent's box crosses
node = sv_areanodes;
while (1)
{
if (node->axis == -1)
break;
if (ent->v.absmin[node->axis] > node->dist)
node = node->children[0];
else if (ent->v.absmax[node->axis] < node->dist)
node = node->children[1];
else
break; // crosses the node
}
// link it in
if (ent->v.solid == SOLID_TRIGGER)
InsertLinkBefore (&ent->area, &node->trigger_edicts);
else
InsertLinkBefore (&ent->area, &node->solid_edicts);
// if touch_triggers, touch all entities at this node and decend for more
if (touch_triggers)
SV_TouchLinks ( ent, sv_areanodes );
}
/*
===============================================================================
POINT TESTING IN HULLS
===============================================================================
*/
/*
==================
SV_HullPointContents
==================
*/
int SV_HullPointContents (hull_t *hull, int num, vec3_t p)
{
float d;
dclipnode_t *node;
mplane_t *plane;
while (num >= 0)
{
if (num < hull->firstclipnode || num > hull->lastclipnode)
Sys_Error ("SV_HullPointContents: bad node number");
node = hull->clipnodes + num;
plane = hull->planes + node->planenum;
if (plane->type < 3)
d = p[plane->type] - plane->dist;
else
d = DotProduct (plane->normal, p) - plane->dist;
if (d < 0)
num = node->children[1];
else
num = node->children[0];
}
return num;
}
/*
==================
SV_PointContents
==================
*/
int SV_PointContents (vec3_t p)
{
int cont;
cont = SV_HullPointContents (&sv.worldmodel->hulls[0], 0, p);
if (cont <= CONTENTS_CURRENT_0 && cont >= CONTENTS_CURRENT_DOWN)
cont = CONTENTS_WATER;
return cont;
}
int SV_TruePointContents (vec3_t p)
{
return SV_HullPointContents (&sv.worldmodel->hulls[0], 0, p);
}
//===========================================================================
/*
============
SV_TestEntityPosition
This could be a lot more efficient...
============
*/
edict_t *SV_TestEntityPosition (edict_t *ent)
{
trace_t trace;
trace = SV_Move (ent->v.origin, ent->v.mins, ent->v.maxs, ent->v.origin, 0, ent);
if (trace.startsolid)
return sv.edicts;
return nil;
}
/*
===============================================================================
LINE TESTING IN HULLS
===============================================================================
*/
// 1/32 epsilon to keep floating point happy
#define DIST_EPSILON (0.03125)
/*
==================
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;
mplane_t *plane;
float t1, t2;
float frac;
int i;
vec3_t mid;
int side;
float midf;
// 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
}
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;
}
/*
if ( (t1 >= DIST_EPSILON && t2 >= DIST_EPSILON) || (t2 > t1 && t1 >= 0) )
return SV_RecursiveHullCheck (hull, node->children[0], p1f, p2f, p1, p2, trace);
if ( (t1 <= -DIST_EPSILON && t2 <= -DIST_EPSILON) || (t2 < t1 && t1 <= 0) )
return SV_RecursiveHullCheck (hull, node->children[1], p1f, p2f, p1, p2, trace);
*/
if (t1 >= 0 && t2 >= 0)
return SV_RecursiveHullCheck (hull, node->children[0], p1f, p2f, p1, p2, trace);
if (t1 < 0 && t2 < 0)
return SV_RecursiveHullCheck (hull, node->children[1], p1f, p2f, p1, p2, trace);
// put the crosspoint DIST_EPSILON pixels on the near side
if (t1 < 0)
frac = (t1 + DIST_EPSILON)/(t1-t2);
else
frac = (t1 - DIST_EPSILON)/(t1-t2);
if (frac < 0)
frac = 0;
if (frac > 1)
frac = 1;
midf = p1f + (p2f - p1f)*frac;
for (i=0 ; i<3 ; i++)
mid[i] = p1[i] + frac*(p2[i] - p1[i]);
side = (t1 < 0);
// move up to the node
if (!SV_RecursiveHullCheck (hull, node->children[side], p1f, midf, p1, mid, trace) )
return false;
#ifdef PARANOID
/* FIXME */
/*if (SV_HullPointContents (sv_hullmodel, mid, node->children[side])*/
if (SV_HullPointContents (hull, mid, node->children[side])
== CONTENTS_SOLID)
{
Con_Printf ("mid PointInHullSolid\n");
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);
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
{
VectorSubtract (vec3_origin, plane->normal, trace->plane.normal);
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;
}
/*
==================
SV_ClipMoveToEntity
Handles selection or creation of a clipping hull, and offseting (and
eventually rotation) of the end points
==================
*/
trace_t SV_ClipMoveToEntity (edict_t *ent, vec3_t start, vec3_t mins, vec3_t maxs, vec3_t end)
{
trace_t trace;
vec3_t offset;
vec3_t start_l, end_l;
hull_t *hull;
// fill in a default trace
memset (&trace, 0, sizeof(trace_t));
trace.fraction = 1;
trace.allsolid = true;
VectorCopy (end, trace.endpos);
// get the clipping hull
hull = SV_HullForEntity (ent, mins, maxs, offset);
VectorSubtract (start, offset, start_l);
VectorSubtract (end, offset, end_l);
// trace a line through the apropriate clipping hull
SV_RecursiveHullCheck (hull, hull->firstclipnode, 0, 1, start_l, end_l, &trace);
// fix trace up by the offset
if (trace.fraction != 1)
VectorAdd (trace.endpos, offset, trace.endpos);
// did we clip the move?
if (trace.fraction < 1 || trace.startsolid )
trace.ent = ent;
return trace;
}
//===========================================================================
/*
====================
SV_ClipToLinks
Mins and maxs enclose the entire area swept by the move
====================
*/
void SV_ClipToLinks ( areanode_t *node, moveclip_t *clip )
{
link_t *l, *next;
edict_t *touch;
trace_t trace;
// touch linked edicts
for (l = node->solid_edicts.next ; l != &node->solid_edicts ; l = next)
{
next = l->next;
touch = EDICT_FROM_AREA(l);
if (touch->v.solid == SOLID_NOT)
continue;
if (touch == clip->passedict)
continue;
if (touch->v.solid == SOLID_TRIGGER)
Sys_Error ("Trigger in clipping list");
if (clip->type == MOVE_NOMONSTERS && touch->v.solid != SOLID_BSP)
continue;
if (clip->boxmins[0] > touch->v.absmax[0]
|| clip->boxmins[1] > touch->v.absmax[1]
|| clip->boxmins[2] > touch->v.absmax[2]
|| clip->boxmaxs[0] < touch->v.absmin[0]
|| clip->boxmaxs[1] < touch->v.absmin[1]
|| clip->boxmaxs[2] < touch->v.absmin[2] )
continue;
if (clip->passedict && clip->passedict->v.size[0] && !touch->v.size[0])
continue; // points never interact
// might intersect, so do an exact clip
if (clip->trace.allsolid)
return;
if (clip->passedict)
{
if (PROG_TO_EDICT(touch->v.owner) == clip->passedict)
continue; // don't clip against own missiles
if (PROG_TO_EDICT(clip->passedict->v.owner) == touch)
continue; // don't clip against owner
}
if ((int)touch->v.flags & FL_MONSTER)
trace = SV_ClipMoveToEntity (touch, clip->start, clip->mins2, clip->maxs2, clip->end);
else
trace = SV_ClipMoveToEntity (touch, clip->start, clip->mins, clip->maxs, clip->end);
if (trace.allsolid || trace.startsolid ||
trace.fraction < clip->trace.fraction)
{
trace.ent = touch;
if (clip->trace.startsolid)
{
clip->trace = trace;
clip->trace.startsolid = true;
}
else
clip->trace = trace;
}
else if (trace.startsolid)
clip->trace.startsolid = true;
}
// recurse down both sides
if (node->axis == -1)
return;
if ( clip->boxmaxs[node->axis] > node->dist )
SV_ClipToLinks ( node->children[0], clip );
if ( clip->boxmins[node->axis] < node->dist )
SV_ClipToLinks ( node->children[1], clip );
}
/*
==================
SV_MoveBounds
==================
*/
void SV_MoveBounds (vec3_t start, vec3_t mins, vec3_t maxs, vec3_t end, vec3_t boxmins, vec3_t boxmaxs)
{
/* debug to test against everything
boxmins[0] = boxmins[1] = boxmins[2] = -9999;
boxmaxs[0] = boxmaxs[1] = boxmaxs[2] = 9999;
*/
int i;
for (i=0 ; i<3 ; i++)
{
if (end[i] > start[i])
{
boxmins[i] = start[i] + mins[i] - 1;
boxmaxs[i] = end[i] + maxs[i] + 1;
}
else
{
boxmins[i] = end[i] + mins[i] - 1;
boxmaxs[i] = start[i] + maxs[i] + 1;
}
}
}
/*
==================
SV_Move
==================
*/
trace_t SV_Move (vec3_t start, vec3_t mins, vec3_t maxs, vec3_t end, int type, edict_t *passedict)
{
moveclip_t clip;
int i;
memset ( &clip, 0, sizeof ( moveclip_t ) );
// clip to world
clip.trace = SV_ClipMoveToEntity ( sv.edicts, start, mins, maxs, end );
clip.start = start;
clip.end = end;
clip.mins = mins;
clip.maxs = maxs;
clip.type = type;
clip.passedict = passedict;
if (type == MOVE_MISSILE)
{
for (i=0 ; i<3 ; i++)
{
clip.mins2[i] = -15;
clip.maxs2[i] = 15;
}
}
else
{
VectorCopy (mins, clip.mins2);
VectorCopy (maxs, clip.maxs2);
}
// create the bounding box of the entire move
SV_MoveBounds ( start, clip.mins2, clip.maxs2, end, clip.boxmins, clip.boxmaxs );
// clip to entities
SV_ClipToLinks ( sv_areanodes, &clip );
return clip.trace;
}