757 lines
16 KiB
C
757 lines
16 KiB
C
#include "bsplib.h"
|
|
|
|
/*
|
|
|
|
each portal will have a list of all possible to see from first portal
|
|
|
|
if (!thread->portalmightsee[portalnum])
|
|
|
|
portal mightsee
|
|
|
|
for p2 = all other portals in leaf
|
|
get sperating planes
|
|
for all portals that might be seen by p2
|
|
mark as unseen if not present in seperating plane
|
|
flood fill a new mightsee
|
|
save as passagemightsee
|
|
|
|
|
|
void CalcMightSee (leaf_t *leaf,
|
|
*/
|
|
|
|
int CountBits (byte *bits, int numbits)
|
|
{
|
|
int i;
|
|
int c;
|
|
|
|
c = 0;
|
|
for (i=0 ; i<numbits ; i++)
|
|
if (bits[i>>3] & (1<<(i&7)) )
|
|
c++;
|
|
|
|
return c;
|
|
}
|
|
|
|
int c_fullskip;
|
|
int c_portalskip, c_leafskip;
|
|
int c_vistest, c_mighttest;
|
|
|
|
int c_chop, c_nochop;
|
|
|
|
int active;
|
|
|
|
void CheckStack (leaf_t *leaf, threaddata_t *thread)
|
|
{
|
|
pstack_t *p, *p2;
|
|
|
|
for (p=thread->pstack_head.next ; p ; p=p->next)
|
|
{
|
|
if (p->leaf == leaf)
|
|
Sys_Error ("CheckStack: leaf recursion");
|
|
for (p2=thread->pstack_head.next ; p2 != p ; p2=p2->next)
|
|
if (p2->leaf == p->leaf)
|
|
Sys_Error ("CheckStack: late leaf recursion");
|
|
}
|
|
}
|
|
|
|
|
|
viswinding_t *AllocStackWinding (pstack_t *stack)
|
|
{
|
|
int i;
|
|
|
|
for (i=0 ; i<3 ; i++)
|
|
{
|
|
if (stack->freewindings[i])
|
|
{
|
|
stack->freewindings[i] = 0;
|
|
return &stack->windings[i];
|
|
}
|
|
}
|
|
|
|
Sys_Error ("AllocStackWinding: failed");
|
|
|
|
return NULL;
|
|
}
|
|
|
|
void FreeStackWinding (viswinding_t *w, pstack_t *stack)
|
|
{
|
|
int i;
|
|
|
|
i = w - stack->windings;
|
|
|
|
if (i<0 || i>2)
|
|
return; // not from local
|
|
|
|
if (stack->freewindings[i])
|
|
Sys_Error ("FreeStackWinding: allready free");
|
|
stack->freewindings[i] = 1;
|
|
}
|
|
|
|
/*
|
|
==============
|
|
ChopWinding
|
|
|
|
==============
|
|
*/
|
|
viswinding_t *ChopWinding (viswinding_t *in, pstack_t *stack, visplane_t *split)
|
|
{
|
|
vec_t dists[128];
|
|
int sides[128];
|
|
int counts[3];
|
|
vec_t dot;
|
|
int i, j;
|
|
vec_t *p1, *p2;
|
|
vec3_t mid;
|
|
viswinding_t *neww;
|
|
|
|
counts[0] = counts[1] = counts[2] = 0;
|
|
|
|
// determine sides for each point
|
|
for (i=0 ; i<in->numpoints ; i++)
|
|
{
|
|
dot = DotProduct (in->points[i], split->normal);
|
|
dot -= split->dist;
|
|
dists[i] = dot;
|
|
if (dot > ON_EPSILON)
|
|
sides[i] = SIDE_FRONT;
|
|
else if (dot < -ON_EPSILON)
|
|
sides[i] = SIDE_BACK;
|
|
else
|
|
{
|
|
sides[i] = SIDE_ON;
|
|
}
|
|
counts[sides[i]]++;
|
|
}
|
|
|
|
if (!counts[1])
|
|
return in; // completely on front side
|
|
|
|
if (!counts[0])
|
|
{
|
|
FreeStackWinding (in, stack);
|
|
return NULL;
|
|
}
|
|
|
|
sides[i] = sides[0];
|
|
dists[i] = dists[0];
|
|
|
|
neww = AllocStackWinding (stack);
|
|
|
|
neww->numpoints = 0;
|
|
|
|
for (i=0 ; i<in->numpoints ; i++)
|
|
{
|
|
p1 = in->points[i];
|
|
|
|
if (neww->numpoints == 12)
|
|
{
|
|
FreeStackWinding (neww, stack);
|
|
return in; // can't chop -- fall back to original
|
|
}
|
|
|
|
if (sides[i] == SIDE_ON)
|
|
{
|
|
VectorCopy (p1, neww->points[neww->numpoints]);
|
|
neww->numpoints++;
|
|
continue;
|
|
}
|
|
|
|
if (sides[i] == SIDE_FRONT)
|
|
{
|
|
VectorCopy (p1, neww->points[neww->numpoints]);
|
|
neww->numpoints++;
|
|
}
|
|
|
|
if (sides[i+1] == SIDE_ON || sides[i+1] == sides[i])
|
|
continue;
|
|
|
|
if (neww->numpoints == 12)
|
|
{
|
|
FreeStackWinding (neww, stack);
|
|
return in; // can't chop -- fall back to original
|
|
}
|
|
|
|
// generate a split point
|
|
p2 = in->points[(i+1)%in->numpoints];
|
|
|
|
dot = dists[i] / (dists[i]-dists[i+1]);
|
|
for (j=0 ; j<3 ; j++)
|
|
{ // avoid round off error when possible
|
|
if (split->normal[j] == 1)
|
|
mid[j] = split->dist;
|
|
else if (split->normal[j] == -1)
|
|
mid[j] = -split->dist;
|
|
else
|
|
mid[j] = p1[j] + dot*(p2[j]-p1[j]);
|
|
}
|
|
|
|
VectorCopy (mid, neww->points[neww->numpoints]);
|
|
neww->numpoints++;
|
|
}
|
|
|
|
// free the original winding
|
|
FreeStackWinding (in, stack);
|
|
|
|
return neww;
|
|
}
|
|
|
|
|
|
/*
|
|
==============
|
|
ClipToSeperators
|
|
|
|
Source, pass, and target are an ordering of portals.
|
|
|
|
Generates seperating planes canidates by taking two points from source and one
|
|
point from pass, and clips target by them.
|
|
|
|
If target is totally clipped away, that portal can not be seen through.
|
|
|
|
Normal clip keeps target on the same side as pass, which is correct if the
|
|
order goes source, pass, target. If the order goes pass, source, target then
|
|
flipclip should be set.
|
|
==============
|
|
*/
|
|
viswinding_t *ClipToSeperators (viswinding_t *source, viswinding_t *pass, viswinding_t *target, bool flipclip, pstack_t *stack)
|
|
{
|
|
int i, j, k, l;
|
|
visplane_t plane;
|
|
vec3_t v1, v2;
|
|
float d;
|
|
vec_t length;
|
|
int counts[3];
|
|
bool fliptest;
|
|
|
|
// check all combinations
|
|
for (i=0 ; i<source->numpoints ; i++)
|
|
{
|
|
l = (i+1)%source->numpoints;
|
|
VectorSubtract (source->points[l] , source->points[i], v1);
|
|
|
|
// fing a vertex of pass that makes a plane that puts all of the
|
|
// vertexes of pass on the front side and all of the vertexes of
|
|
// source on the back side
|
|
for (j=0 ; j<pass->numpoints ; j++)
|
|
{
|
|
VectorSubtract (pass->points[j], source->points[i], v2);
|
|
|
|
plane.normal[0] = v1[1]*v2[2] - v1[2]*v2[1];
|
|
plane.normal[1] = v1[2]*v2[0] - v1[0]*v2[2];
|
|
plane.normal[2] = v1[0]*v2[1] - v1[1]*v2[0];
|
|
|
|
// if points don't make a valid plane, skip it
|
|
|
|
length = plane.normal[0] * plane.normal[0]
|
|
+ plane.normal[1] * plane.normal[1]
|
|
+ plane.normal[2] * plane.normal[2];
|
|
|
|
if (length < ON_EPSILON)
|
|
continue;
|
|
|
|
length = 1/sqrt(length);
|
|
|
|
plane.normal[0] *= length;
|
|
plane.normal[1] *= length;
|
|
plane.normal[2] *= length;
|
|
|
|
plane.dist = DotProduct (pass->points[j], plane.normal);
|
|
|
|
//
|
|
// find out which side of the generated seperating plane has the
|
|
// source portal
|
|
//
|
|
#if 1
|
|
fliptest = false;
|
|
for (k=0 ; k<source->numpoints ; k++)
|
|
{
|
|
if (k == i || k == l)
|
|
continue;
|
|
d = DotProduct (source->points[k], plane.normal) - plane.dist;
|
|
if (d < -ON_EPSILON)
|
|
{ // source is on the negative side, so we want all
|
|
// pass and target on the positive side
|
|
fliptest = false;
|
|
break;
|
|
}
|
|
else if (d > ON_EPSILON)
|
|
{ // source is on the positive side, so we want all
|
|
// pass and target on the negative side
|
|
fliptest = true;
|
|
break;
|
|
}
|
|
}
|
|
if (k == source->numpoints)
|
|
continue; // planar with source portal
|
|
#else
|
|
fliptest = flipclip;
|
|
#endif
|
|
//
|
|
// flip the normal if the source portal is backwards
|
|
//
|
|
if (fliptest)
|
|
{
|
|
VectorSubtract (vec3_origin, plane.normal, plane.normal);
|
|
plane.dist = -plane.dist;
|
|
}
|
|
#if 1
|
|
//
|
|
// if all of the pass portal points are now on the positive side,
|
|
// this is the seperating plane
|
|
//
|
|
counts[0] = counts[1] = counts[2] = 0;
|
|
for (k=0 ; k<pass->numpoints ; k++)
|
|
{
|
|
if (k==j)
|
|
continue;
|
|
d = DotProduct (pass->points[k], plane.normal) - plane.dist;
|
|
if (d < -ON_EPSILON)
|
|
break;
|
|
else if (d > ON_EPSILON)
|
|
counts[0]++;
|
|
else
|
|
counts[2]++;
|
|
}
|
|
if (k != pass->numpoints)
|
|
continue; // points on negative side, not a seperating plane
|
|
|
|
if (!counts[0])
|
|
continue; // planar with seperating plane
|
|
#else
|
|
k = (j+1)%pass->numpoints;
|
|
d = DotProduct (pass->points[k], plane.normal) - plane.dist;
|
|
if (d < -ON_EPSILON)
|
|
continue;
|
|
k = (j+pass->numpoints-1)%pass->numpoints;
|
|
d = DotProduct (pass->points[k], plane.normal) - plane.dist;
|
|
if (d < -ON_EPSILON)
|
|
continue;
|
|
#endif
|
|
//
|
|
// flip the normal if we want the back side
|
|
//
|
|
if (flipclip)
|
|
{
|
|
VectorSubtract (vec3_origin, plane.normal, plane.normal);
|
|
plane.dist = -plane.dist;
|
|
}
|
|
|
|
//
|
|
// clip target by the seperating plane
|
|
//
|
|
target = ChopWinding (target, stack, &plane);
|
|
if (!target)
|
|
return NULL; // target is not visible
|
|
}
|
|
}
|
|
|
|
return target;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
==================
|
|
RecursiveLeafFlow
|
|
|
|
Flood fill through the leafs
|
|
If src_portal is NULL, this is the originating leaf
|
|
==================
|
|
*/
|
|
void RecursiveLeafFlow (int leafnum, threaddata_t *thread, pstack_t *prevstack)
|
|
{
|
|
pstack_t stack;
|
|
visportal_t *p;
|
|
visplane_t backplane;
|
|
leaf_t *leaf;
|
|
int i, j;
|
|
long *test, *might, *vis, more;
|
|
int pnum;
|
|
|
|
thread->c_chains++;
|
|
|
|
leaf = &leafs[leafnum];
|
|
// CheckStack (leaf, thread);
|
|
|
|
prevstack->next = &stack;
|
|
|
|
stack.next = NULL;
|
|
stack.leaf = leaf;
|
|
stack.portal = NULL;
|
|
|
|
might = (long *)stack.mightsee;
|
|
vis = (long *)thread->base->portalvis;
|
|
|
|
// check all portals for flowing into other leafs
|
|
for (i=0 ; i<leaf->numportals ; i++)
|
|
{
|
|
p = leaf->portals[i];
|
|
pnum = p - portals;
|
|
|
|
if ( ! (prevstack->mightsee[pnum >> 3] & (1<<(pnum&7)) ) )
|
|
{
|
|
continue; // can't possibly see it
|
|
}
|
|
|
|
// if the portal can't see anything we haven't allready seen, skip it
|
|
if (p->status == stat_done)
|
|
{
|
|
test = (long *)p->portalvis;
|
|
}
|
|
else
|
|
{
|
|
test = (long *)p->portalflood;
|
|
}
|
|
|
|
more = 0;
|
|
for (j=0 ; j<portallongs ; j++)
|
|
{
|
|
might[j] = ((long *)prevstack->mightsee)[j] & test[j];
|
|
more |= (might[j] & ~vis[j]);
|
|
}
|
|
|
|
if (!more &&
|
|
(thread->base->portalvis[pnum>>3] & (1<<(pnum&7))) )
|
|
{ // can't see anything new
|
|
continue;
|
|
}
|
|
|
|
// get plane of portal, point normal into the neighbor leaf
|
|
stack.portalplane = p->plane;
|
|
VectorSubtract (vec3_origin, p->plane.normal, backplane.normal);
|
|
backplane.dist = -p->plane.dist;
|
|
|
|
// c_portalcheck++;
|
|
|
|
stack.portal = p;
|
|
stack.next = NULL;
|
|
stack.freewindings[0] = 1;
|
|
stack.freewindings[1] = 1;
|
|
stack.freewindings[2] = 1;
|
|
|
|
#if 1
|
|
{
|
|
float d;
|
|
|
|
d = DotProduct (p->origin, thread->pstack_head.portalplane.normal);
|
|
d -= thread->pstack_head.portalplane.dist;
|
|
if (d < -p->radius)
|
|
{
|
|
continue;
|
|
}
|
|
else if (d > p->radius)
|
|
{
|
|
stack.pass = p->winding;
|
|
}
|
|
else
|
|
{
|
|
stack.pass = ChopWinding (p->winding, &stack, &thread->pstack_head.portalplane);
|
|
if (!stack.pass)
|
|
continue;
|
|
}
|
|
}
|
|
#else
|
|
stack.pass = ChopWinding (p->winding, &stack, &thread->pstack_head.portalplane);
|
|
if (!stack.pass)
|
|
continue;
|
|
#endif
|
|
|
|
|
|
#if 1
|
|
{
|
|
float d;
|
|
|
|
d = DotProduct (thread->base->origin, p->plane.normal);
|
|
d -= p->plane.dist;
|
|
if (d > p->radius)
|
|
{
|
|
continue;
|
|
}
|
|
else if (d < -p->radius)
|
|
{
|
|
stack.source = prevstack->source;
|
|
}
|
|
else
|
|
{
|
|
stack.source = ChopWinding (prevstack->source, &stack, &backplane);
|
|
if (!stack.source)
|
|
continue;
|
|
}
|
|
}
|
|
#else
|
|
stack.source = ChopWinding (prevstack->source, &stack, &backplane);
|
|
if (!stack.source)
|
|
continue;
|
|
#endif
|
|
|
|
if (!prevstack->pass)
|
|
{ // the second leaf can only be blocked if coplanar
|
|
|
|
// mark the portal as visible
|
|
thread->base->portalvis[pnum>>3] |= (1<<(pnum&7));
|
|
|
|
RecursiveLeafFlow (p->leaf, thread, &stack);
|
|
continue;
|
|
}
|
|
|
|
stack.pass = ClipToSeperators (stack.source, prevstack->pass, stack.pass, false, &stack);
|
|
if (!stack.pass)
|
|
continue;
|
|
|
|
stack.pass = ClipToSeperators (prevstack->pass, stack.source, stack.pass, true, &stack);
|
|
if (!stack.pass)
|
|
continue;
|
|
|
|
// mark the portal as visible
|
|
thread->base->portalvis[pnum>>3] |= (1<<(pnum&7));
|
|
|
|
// flow through it for real
|
|
RecursiveLeafFlow (p->leaf, thread, &stack);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
===============
|
|
PortalFlow
|
|
|
|
generates the portalvis bit vector
|
|
===============
|
|
*/
|
|
void PortalFlow (int portalnum)
|
|
{
|
|
threaddata_t data;
|
|
int i;
|
|
visportal_t *p;
|
|
int c_might, c_can;
|
|
|
|
p = sorted_portals[portalnum];
|
|
p->status = stat_working;
|
|
|
|
c_might = CountBits (p->portalflood, numportals*2);
|
|
|
|
memset (&data, 0, sizeof(data));
|
|
data.base = p;
|
|
|
|
data.pstack_head.portal = p;
|
|
data.pstack_head.source = p->winding;
|
|
data.pstack_head.portalplane = p->plane;
|
|
for (i=0 ; i<portallongs ; i++)
|
|
((long *)data.pstack_head.mightsee)[i] = ((long *)p->portalflood)[i];
|
|
RecursiveLeafFlow (p->leaf, &data, &data.pstack_head);
|
|
|
|
p->status = stat_done;
|
|
|
|
c_can = CountBits (p->portalvis, numportals*2);
|
|
}
|
|
|
|
|
|
/*
|
|
===============================================================================
|
|
|
|
This is a rough first-order aproximation that is used to trivially reject some
|
|
of the final calculations.
|
|
|
|
|
|
Calculates portalfront and portalflood bit vectors
|
|
|
|
thinking about:
|
|
|
|
typedef struct passage_s
|
|
{
|
|
struct passage_s *next;
|
|
struct portal_s *to;
|
|
stryct sep_s *seperators;
|
|
byte *mightsee;
|
|
} passage_t;
|
|
|
|
typedef struct portal_s
|
|
{
|
|
struct passage_s *passages;
|
|
int leaf; // leaf portal faces into
|
|
} portal_s;
|
|
|
|
leaf = portal->leaf
|
|
clear
|
|
for all portals
|
|
|
|
|
|
calc portal visibility
|
|
clear bit vector
|
|
for all passages
|
|
passage visibility
|
|
|
|
|
|
for a portal to be visible to a passage, it must be on the front of
|
|
all seperating planes, and both portals must be behind the mew portal
|
|
|
|
===============================================================================
|
|
*/
|
|
|
|
int c_flood, c_vis;
|
|
|
|
|
|
/*
|
|
==================
|
|
SimpleFlood
|
|
|
|
==================
|
|
*/
|
|
void SimpleFlood (visportal_t *srcportal, int leafnum)
|
|
{
|
|
int i;
|
|
leaf_t *leaf;
|
|
visportal_t *p;
|
|
int pnum;
|
|
|
|
leaf = &leafs[leafnum];
|
|
|
|
for (i=0 ; i<leaf->numportals ; i++)
|
|
{
|
|
p = leaf->portals[i];
|
|
pnum = p - portals;
|
|
if ( ! (srcportal->portalfront[pnum>>3] & (1<<(pnum&7)) ) )
|
|
continue;
|
|
|
|
if (srcportal->portalflood[pnum>>3] & (1<<(pnum&7)) )
|
|
continue;
|
|
|
|
srcportal->portalflood[pnum>>3] |= (1<<(pnum&7));
|
|
|
|
SimpleFlood (srcportal, p->leaf);
|
|
}
|
|
}
|
|
|
|
/*
|
|
==============
|
|
BasePortalVis
|
|
==============
|
|
*/
|
|
void BasePortalVis (int portalnum)
|
|
{
|
|
int j, k;
|
|
visportal_t *tp, *p;
|
|
float d;
|
|
viswinding_t *w;
|
|
|
|
p = portals+portalnum;
|
|
|
|
p->portalfront = Malloc (portalbytes);
|
|
p->portalflood = Malloc (portalbytes);
|
|
p->portalvis = Malloc (portalbytes);
|
|
|
|
for (j=0, tp = portals ; j<numportals*2 ; j++, tp++)
|
|
{
|
|
if (j == portalnum)
|
|
continue;
|
|
w = tp->winding;
|
|
for (k=0 ; k<w->numpoints ; k++)
|
|
{
|
|
d = DotProduct (w->points[k], p->plane.normal)
|
|
- p->plane.dist;
|
|
if (d > ON_EPSILON)
|
|
break;
|
|
}
|
|
if (k == w->numpoints)
|
|
continue; // no points on front
|
|
|
|
w = p->winding;
|
|
for (k=0 ; k<w->numpoints ; k++)
|
|
{
|
|
d = DotProduct (w->points[k], tp->plane.normal)
|
|
- tp->plane.dist;
|
|
if (d < -ON_EPSILON)
|
|
break;
|
|
}
|
|
if (k == w->numpoints)
|
|
continue; // no points on front
|
|
|
|
p->portalfront[j>>3] |= (1<<(j&7));
|
|
}
|
|
|
|
SimpleFlood (p, p->leaf);
|
|
|
|
p->nummightsee = CountBits (p->portalflood, numportals*2);
|
|
c_flood += p->nummightsee;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
===============================================================================
|
|
|
|
This is a second order aproximation
|
|
|
|
Calculates portalvis bit vector
|
|
|
|
WAAAAAAY too slow.
|
|
|
|
===============================================================================
|
|
*/
|
|
|
|
/*
|
|
==================
|
|
RecursiveLeafBitFlow
|
|
|
|
==================
|
|
*/
|
|
void RecursiveLeafBitFlow (int leafnum, byte *mightsee, byte *cansee)
|
|
{
|
|
visportal_t *p;
|
|
leaf_t *leaf;
|
|
int i, j;
|
|
long more;
|
|
int pnum;
|
|
byte newmight[MAX_PORTALS/8];
|
|
|
|
leaf = &leafs[leafnum];
|
|
|
|
// check all portals for flowing into other leafs
|
|
for (i=0 ; i<leaf->numportals ; i++)
|
|
{
|
|
p = leaf->portals[i];
|
|
pnum = p - portals;
|
|
|
|
// if some previous portal can't see it, skip
|
|
if (! (mightsee[pnum>>3] & (1<<(pnum&7)) ) )
|
|
continue;
|
|
|
|
// if this portal can see some portals we mightsee, recurse
|
|
more = 0;
|
|
for (j=0 ; j<portallongs ; j++)
|
|
{
|
|
((long *)newmight)[j] = ((long *)mightsee)[j]
|
|
& ((long *)p->portalflood)[j];
|
|
more |= ((long *)newmight)[j] & ~((long *)cansee)[j];
|
|
}
|
|
|
|
if (!more)
|
|
continue; // can't see anything new
|
|
|
|
cansee[pnum>>3] |= (1<<(pnum&7));
|
|
|
|
RecursiveLeafBitFlow (p->leaf, newmight, cansee);
|
|
}
|
|
}
|
|
|
|
/*
|
|
==============
|
|
BetterPortalVis
|
|
==============
|
|
*/
|
|
void BetterPortalVis (int portalnum)
|
|
{
|
|
visportal_t *p;
|
|
|
|
p = portals+portalnum;
|
|
|
|
RecursiveLeafBitFlow (p->leaf, p->portalflood, p->portalvis);
|
|
|
|
// build leaf vis information
|
|
p->nummightsee = CountBits (p->portalvis, numportals*2);
|
|
c_vis += p->nummightsee;
|
|
}
|
|
|
|
|