ericw-tools/qbsp/tjunc.c

532 lines
10 KiB
C

/*
Copyright (C) 1996-1997 Id Software, Inc.
Copyright (C) 1997 Greg Lewis
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
See file, 'COPYING', for details.
*/
// tjunc.c
#include "qbsp.h"
int numwedges, numwverts;
int tjuncs;
int tjuncfaces;
int cWVerts;
int cWEdges;
wvert_t *pWVerts;
wedge_t *pWEdges;
void PrintFace (face_t *f)
{
int i;
for (i=0 ; i<f->numpoints ; i++)
printf ("(%5.2f, %5.2f, %5.2f)\n", f->pts[i][0], f->pts[i][1], f->pts[i][2]);
}
//============================================================================
#define NUM_HASH 1024
wedge_t *wedge_hash[NUM_HASH];
static vec3_t hash_min, hash_scale;
static void InitHash (vec3_t mins, vec3_t maxs)
{
vec3_t size;
vec_t volume;
vec_t scale;
int newsize[2];
VectorCopy (mins, hash_min);
VectorSubtract (maxs, mins, size);
memset (wedge_hash, 0, sizeof(wedge_hash));
volume = size[0]*size[1];
scale = sqrt(volume / NUM_HASH);
newsize[0] = (int)(size[0] / scale);
newsize[1] = (int)(size[1] / scale);
hash_scale[0] = newsize[0] / size[0];
hash_scale[1] = newsize[1] / size[1];
hash_scale[2] = (float)newsize[1];
}
static unsigned HashVec (vec3_t vec)
{
unsigned h;
h = (unsigned)(hash_scale[0] * (vec[0] - hash_min[0]) * hash_scale[2] +
hash_scale[1] * (vec[1] - hash_min[1]));
if ( h >= NUM_HASH)
return NUM_HASH - 1;
return h;
}
//============================================================================
void CanonicalVector (vec3_t vec)
{
VectorNormalize (vec);
if (vec[0] > EQUAL_EPSILON)
return;
else if (vec[0] < -EQUAL_EPSILON)
{
VectorSubtract (vec3_origin, vec, vec);
return;
}
else
vec[0] = 0;
if (vec[1] > EQUAL_EPSILON)
return;
else if (vec[1] < -EQUAL_EPSILON)
{
VectorSubtract (vec3_origin, vec, vec);
return;
}
else
vec[1] = 0;
if (vec[2] > EQUAL_EPSILON)
return;
else if (vec[2] < -EQUAL_EPSILON)
{
VectorSubtract (vec3_origin, vec, vec);
return;
}
else
vec[2] = 0;
Message(msgError, errDegenerateEdge, vec[0], vec[1], vec[2]);
}
wedge_t *FindEdge (vec3_t p1, vec3_t p2, vec_t *t1, vec_t *t2)
{
vec3_t origin;
vec3_t dir;
wedge_t *w;
vec_t temp;
int h;
VectorSubtract (p2, p1, dir);
CanonicalVector (dir);
*t1 = DotProduct (p1, dir);
*t2 = DotProduct (p2, dir);
VectorMA (p1, -*t1, dir, origin);
if (*t1 > *t2)
{
temp = *t1;
*t1 = *t2;
*t2 = temp;
}
h = HashVec (origin);
for (w = wedge_hash[h] ; w ; w=w->next)
{
temp = w->origin[0] - origin[0];
if (temp < -EQUAL_EPSILON || temp > EQUAL_EPSILON)
continue;
temp = w->origin[1] - origin[1];
if (temp < -EQUAL_EPSILON || temp > EQUAL_EPSILON)
continue;
temp = w->origin[2] - origin[2];
if (temp < -EQUAL_EPSILON || temp > EQUAL_EPSILON)
continue;
temp = w->dir[0] - dir[0];
if (temp < -EQUAL_EPSILON || temp > EQUAL_EPSILON)
continue;
temp = w->dir[1] - dir[1];
if (temp < -EQUAL_EPSILON || temp > EQUAL_EPSILON)
continue;
temp = w->dir[2] - dir[2];
if (temp < -EQUAL_EPSILON || temp > EQUAL_EPSILON)
continue;
return w;
}
if (numwedges >= cWEdges)
Message(msgError, errLowWedgeCount);
w = pWEdges+numwedges;
numwedges++;
w->next = wedge_hash[h];
wedge_hash[h] = w;
VectorCopy (origin, w->origin);
VectorCopy (dir, w->dir);
w->head.next = w->head.prev = &w->head;
w->head.t = 99999;
return w;
}
/*
===============
AddVert
===============
*/
#define T_EPSILON 0.01
void AddVert (wedge_t *w, vec_t t)
{
wvert_t *v, *newv;
v = w->head.next;
do
{
if (fabs(v->t - t) < T_EPSILON)
return;
if (v->t > t)
break;
v = v->next;
} while (1);
// insert a new wvert before v
if (numwverts >= cWVerts)
Message(msgError, errLowWvertCount);
newv = pWVerts+numwverts;
numwverts++;
newv->t = t;
newv->next = v;
newv->prev = v->prev;
v->prev->next = newv;
v->prev = newv;
}
/*
===============
AddEdge
===============
*/
void AddEdge (vec3_t p1, vec3_t p2)
{
wedge_t *w;
vec_t t1, t2;
w = FindEdge(p1, p2, &t1, &t2);
AddVert (w, t1);
AddVert (w, t2);
}
/*
===============
AddFaceEdges
===============
*/
void AddFaceEdges (face_t *f)
{
int i, j;
for (i=0 ; i < f->numpoints ; i++)
{
j = (i+1)%f->numpoints;
AddEdge (f->pts[i], f->pts[j]);
}
}
//============================================================================
// a specially allocated face that can hold hundreds of edges if needed
byte superfacebuf[8192];
face_t *superface = (face_t *)superfacebuf;
void FixFaceEdges (face_t *f);
face_t *newlist;
void SplitFaceForTjunc (face_t *f, face_t *original)
{
int i;
face_t *newf, *chain;
vec3_t dir, test;
vec_t v;
int firstcorner, lastcorner;
chain = NULL;
do
{
if (f->numpoints <= MAXPOINTS)
{ // the face is now small enough without more cutting
// so copy it back to the original
*original = *f;
original->original = chain;
original->next = newlist;
newlist = original;
return;
}
tjuncfaces++;
restart:
// find the last corner
VectorSubtract (f->pts[f->numpoints-1], f->pts[0], dir);
VectorNormalize (dir);
for (lastcorner=f->numpoints-1 ; lastcorner > 0 ; lastcorner--)
{
VectorSubtract (f->pts[lastcorner-1], f->pts[lastcorner], test);
VectorNormalize (test);
v = DotProduct (test, dir);
if (v < 0.9999 || v > 1.00001)
{
break;
}
}
// find the first corner
VectorSubtract (f->pts[1], f->pts[0], dir);
VectorNormalize (dir);
for (firstcorner=1 ; firstcorner < f->numpoints-1 ; firstcorner++)
{
VectorSubtract (f->pts[firstcorner+1], f->pts[firstcorner], test);
VectorNormalize (test);
v = DotProduct (test, dir);
if (v < 0.9999 || v > 1.00001)
{
break;
}
}
if (firstcorner+2 >= MAXPOINTS)
{
// rotate the point winding
VectorCopy (f->pts[0], test);
for (i=1 ; i<f->numpoints ; i++)
{
VectorCopy (f->pts[i], f->pts[i-1]);
}
VectorCopy (test, f->pts[f->numpoints-1]);
goto restart;
}
// cut off as big a piece as possible, less than MAXPOINTS, and not
// past lastcorner
newf = NewFaceFromFace (f);
if (f->original)
Message(msgError, errOriginalExists);
newf->original = chain;
chain = newf;
newf->next = newlist;
newlist = newf;
if (f->numpoints - firstcorner <= MAXPOINTS)
newf->numpoints = firstcorner+2;
else if (lastcorner+2 < MAXPOINTS &&
f->numpoints - lastcorner <= MAXPOINTS)
newf->numpoints = lastcorner+2;
else
newf->numpoints = MAXPOINTS;
for (i=0 ; i<newf->numpoints ; i++)
{
VectorCopy (f->pts[i], newf->pts[i]);
}
for (i=newf->numpoints-1 ; i<f->numpoints ; i++)
{
VectorCopy (f->pts[i], f->pts[i-(newf->numpoints-2)]);
}
f->numpoints -= (newf->numpoints-2);
} while (1);
}
/*
===============
FixFaceEdges
===============
*/
void FixFaceEdges (face_t *f)
{
int i, j, k;
wedge_t *w;
wvert_t *v;
vec_t t1, t2;
*superface = *f;
restart:
for (i=0 ; i < superface->numpoints ; i++)
{
j = (i+1)%superface->numpoints;
w = FindEdge (superface->pts[i], superface->pts[j], &t1, &t2);
for (v=w->head.next ; v->t < t1 + T_EPSILON ; v = v->next)
{
}
if (v->t < t2-T_EPSILON)
{
tjuncs++;
// insert a new vertex here
for (k = superface->numpoints ; k> j ; k--)
{
VectorCopy (superface->pts[k-1], superface->pts[k]);
}
VectorMA (w->origin, v->t, w->dir, superface->pts[j]);
superface->numpoints++;
goto restart;
}
}
if (superface->numpoints <= MAXPOINTS)
{
*f = *superface;
f->next = newlist;
newlist = f;
return;
}
// the face needs to be split into multiple faces because of too many edges
SplitFaceForTjunc (superface, f);
}
//============================================================================
void tjunc_count_r(node_t *node)
{
face_t *f;
if (node->planenum == PLANENUM_LEAF)
return;
for (f=node->faces ; f ; f=f->next)
cWVerts += f->numpoints;
tjunc_count_r (node->children[0]);
tjunc_count_r (node->children[1]);
}
void tjunc_find_r(node_t *node)
{
face_t *f;
if (node->planenum == PLANENUM_LEAF)
return;
for (f=node->faces ; f ; f=f->next)
AddFaceEdges (f);
tjunc_find_r (node->children[0]);
tjunc_find_r (node->children[1]);
}
void tjunc_fix_r(node_t *node)
{
face_t *f, *next;
if (node->planenum == PLANENUM_LEAF)
return;
newlist = NULL;
for (f=node->faces ; f ; f=next)
{
next = f->next;
FixFaceEdges (f);
}
node->faces = newlist;
tjunc_fix_r (node->children[0]);
tjunc_fix_r (node->children[1]);
}
/*
===========
tjunc
===========
*/
void tjunc (node_t *headnode)
{
vec3_t maxs, mins;
int i;
Message(msgProgress, "Tjunc");
// Guess edges = 1/2 verts
// Verts are arbitrarily multiplied by 2 because there appears to
// be a need for them to "grow" slightly.
cWVerts = 0;
tjunc_count_r(headnode);
cWEdges = cWVerts;
cWVerts *= 2;
pWVerts = (wvert_t *)AllocMem(WVERT, cWVerts);
pWEdges = (wedge_t *)AllocMem(WEDGE, cWEdges);
// identify all points on common edges
// origin points won't allways be inside the map, so extend the hash area
for (i=0 ; i<3 ; i++)
{
if ( fabs(pCurEnt->maxs[i]) > fabs(pCurEnt->mins[i]) )
maxs[i] = fabs(pCurEnt->maxs[i]);
else
maxs[i] = fabs(pCurEnt->mins[i]);
}
VectorSubtract (vec3_origin, maxs, mins);
InitHash (mins, maxs);
numwedges = numwverts = 0;
tjunc_find_r (headnode);
Message(msgStat, "%5i world edges", numwedges);
Message(msgStat, "%5i edge points", numwverts);
// add extra vertexes on edges where needed
tjuncs = tjuncfaces = 0;
tjunc_fix_r (headnode);
FreeMem(pWVerts, WVERT, cWVerts);
FreeMem(pWEdges, WEDGE, cWEdges);
Message(msgStat, "%5i edges added by tjunctions", tjuncs);
Message(msgStat, "%5i faces added by tjunctions", tjuncfaces);
}