gtkradiant/tools/quake2/q2map/csg.c
TTimo 9998050654 set eol-style
git-svn-id: svn://svn.icculus.org/gtkradiant/GtkRadiant/branches/ZeroRadiant@183 8a3a26a2-13c4-0310-b231-cf6edde360e5
2007-11-04 03:34:51 +00:00

634 lines
12 KiB
C

/*
Copyright (C) 1999-2007 id Software, Inc. and contributors.
For a list of contributors, see the accompanying CONTRIBUTORS file.
This file is part of GtkRadiant.
GtkRadiant 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.
GtkRadiant 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 GtkRadiant; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "qbsp.h"
/*
tag all brushes with original contents
brushes may contain multiple contents
there will be no brush overlap after csg phase
each side has a count of the other sides it splits
the best split will be the one that minimizes the total split counts
of all remaining sides
precalc side on plane table
evaluate split side
{
cost = 0
for all sides
for all sides
get
if side splits side and splitside is on same child
cost++;
}
*/
void SplitBrush2 (bspbrush_t *brush, int planenum,
bspbrush_t **front, bspbrush_t **back)
{
SplitBrush (brush, planenum, front, back);
#if 0
if (*front && (*front)->sides[(*front)->numsides-1].texinfo == -1)
(*front)->sides[(*front)->numsides-1].texinfo = (*front)->sides[0].texinfo; // not -1
if (*back && (*back)->sides[(*back)->numsides-1].texinfo == -1)
(*back)->sides[(*back)->numsides-1].texinfo = (*back)->sides[0].texinfo; // not -1
#endif
}
/*
===============
SubtractBrush
Returns a list of brushes that remain after B is subtracted from A.
May by empty if A is contained inside B.
The originals are undisturbed.
===============
*/
bspbrush_t *SubtractBrush (bspbrush_t *a, bspbrush_t *b)
{ // a - b = out (list)
int i;
bspbrush_t *front, *back;
bspbrush_t *out, *in;
in = a;
out = NULL;
for (i=0 ; i<b->numsides && in ; i++)
{
SplitBrush2 (in, b->sides[i].planenum, &front, &back);
if (in != a)
FreeBrush (in);
if (front)
{ // add to list
front->next = out;
out = front;
}
in = back;
}
if (in)
FreeBrush (in);
else
{ // didn't really intersect
FreeBrushList (out);
return a;
}
return out;
}
/*
===============
IntersectBrush
Returns a single brush made up by the intersection of the
two provided brushes, or NULL if they are disjoint.
The originals are undisturbed.
===============
*/
bspbrush_t *IntersectBrush (bspbrush_t *a, bspbrush_t *b)
{
int i;
bspbrush_t *front, *back;
bspbrush_t *in;
in = a;
for (i=0 ; i<b->numsides && in ; i++)
{
SplitBrush2 (in, b->sides[i].planenum, &front, &back);
if (in != a)
FreeBrush (in);
if (front)
FreeBrush (front);
in = back;
}
if (in == a)
return NULL;
in->next = NULL;
return in;
}
/*
===============
BrushesDisjoint
Returns true if the two brushes definately do not intersect.
There will be false negatives for some non-axial combinations.
===============
*/
qboolean BrushesDisjoint (bspbrush_t *a, bspbrush_t *b)
{
int i, j;
// check bounding boxes
for (i=0 ; i<3 ; i++)
if (a->mins[i] >= b->maxs[i]
|| a->maxs[i] <= b->mins[i])
return true; // bounding boxes don't overlap
// check for opposing planes
for (i=0 ; i<a->numsides ; i++)
{
for (j=0 ; j<b->numsides ; j++)
{
if (a->sides[i].planenum ==
(b->sides[j].planenum^1) )
return true; // opposite planes, so not touching
}
}
return false; // might intersect
}
/*
===============
IntersectionContents
Returns a content word for the intersection of two brushes.
Some combinations will generate a combination (water + clip),
but most will be the stronger of the two contents.
===============
*/
int IntersectionContents (int c1, int c2)
{
int out;
out = c1 | c2;
if (out & CONTENTS_SOLID)
out = CONTENTS_SOLID;
return out;
}
int minplanenums[3];
int maxplanenums[3];
/*
===============
ClipBrushToBox
Any planes shared with the box edge will be set to no texinfo
===============
*/
bspbrush_t *ClipBrushToBox (bspbrush_t *brush, vec3_t clipmins, vec3_t clipmaxs)
{
int i, j;
bspbrush_t *front, *back;
int p;
for (j=0 ; j<2 ; j++)
{
if (brush->maxs[j] > clipmaxs[j])
{
SplitBrush (brush, maxplanenums[j], &front, &back);
if (front)
FreeBrush (front);
brush = back;
if (!brush)
return NULL;
}
if (brush->mins[j] < clipmins[j])
{
SplitBrush (brush, minplanenums[j], &front, &back);
if (back)
FreeBrush (back);
brush = front;
if (!brush)
return NULL;
}
}
// remove any colinear faces
for (i=0 ; i<brush->numsides ; i++)
{
p = brush->sides[i].planenum & ~1;
if (p == maxplanenums[0] || p == maxplanenums[1]
|| p == minplanenums[0] || p == minplanenums[1])
{
brush->sides[i].texinfo = TEXINFO_NODE;
brush->sides[i].visible = false;
}
}
return brush;
}
/*
===============
MakeBspBrushList
===============
*/
bspbrush_t *MakeBspBrushList (int startbrush, int endbrush,
vec3_t clipmins, vec3_t clipmaxs)
{
mapbrush_t *mb;
bspbrush_t *brushlist, *newbrush;
int i, j;
int c_faces;
int c_brushes;
int numsides;
int vis;
vec3_t normal;
float dist;
for (i=0 ; i<2 ; i++)
{
VectorClear (normal);
normal[i] = 1;
dist = clipmaxs[i];
maxplanenums[i] = FindFloatPlane (normal, dist);
dist = clipmins[i];
minplanenums[i] = FindFloatPlane (normal, dist);
}
brushlist = NULL;
c_faces = 0;
c_brushes = 0;
for (i=startbrush ; i<endbrush ; i++)
{
mb = &mapbrushes[i];
numsides = mb->numsides;
if (!numsides)
continue;
// make sure the brush has at least one face showing
vis = 0;
for (j=0 ; j<numsides ; j++)
if (mb->original_sides[j].visible && mb->original_sides[j].winding)
vis++;
#if 0
if (!vis)
continue; // no faces at all
#endif
// if the brush is outside the clip area, skip it
for (j=0 ; j<3 ; j++)
if (mb->mins[j] >= clipmaxs[j]
|| mb->maxs[j] <= clipmins[j])
break;
if (j != 3)
continue;
//
// make a copy of the brush
//
newbrush = AllocBrush (mb->numsides);
newbrush->original = mb;
newbrush->numsides = mb->numsides;
memcpy (newbrush->sides, mb->original_sides, numsides*sizeof(side_t));
for (j=0 ; j<numsides ; j++)
{
if (newbrush->sides[j].winding)
newbrush->sides[j].winding = CopyWinding (newbrush->sides[j].winding);
if (newbrush->sides[j].surf & SURF_HINT)
newbrush->sides[j].visible = true; // hints are always visible
}
VectorCopy (mb->mins, newbrush->mins);
VectorCopy (mb->maxs, newbrush->maxs);
//
// carve off anything outside the clip box
//
newbrush = ClipBrushToBox (newbrush, clipmins, clipmaxs);
if (!newbrush)
continue;
c_faces += vis;
c_brushes++;
newbrush->next = brushlist;
brushlist = newbrush;
}
return brushlist;
}
/*
===============
AddBspBrushListToTail
===============
*/
bspbrush_t *AddBrushListToTail (bspbrush_t *list, bspbrush_t *tail)
{
bspbrush_t *walk, *next;
for (walk=list ; walk ; walk=next)
{ // add to end of list
next = walk->next;
walk->next = NULL;
tail->next = walk;
tail = walk;
}
return tail;
}
/*
===========
CullList
Builds a new list that doesn't hold the given brush
===========
*/
bspbrush_t *CullList (bspbrush_t *list, bspbrush_t *skip1)
{
bspbrush_t *newlist;
bspbrush_t *next;
newlist = NULL;
for ( ; list ; list = next)
{
next = list->next;
if (list == skip1)
{
FreeBrush (list);
continue;
}
list->next = newlist;
newlist = list;
}
return newlist;
}
/*
==================
WriteBrushMap
==================
*/
void WriteBrushMap (char *name, bspbrush_t *list)
{
FILE *f;
side_t *s;
int i;
winding_t *w;
Sys_Printf ("writing %s\n", name);
f = fopen (name, "wb");
if (!f)
Error ("Can't write %s\b", name);
fprintf (f, "{\n\"classname\" \"worldspawn\"\n");
for ( ; list ; list=list->next )
{
fprintf (f, "{\n");
for (i=0,s=list->sides ; i<list->numsides ; i++,s++)
{
w = BaseWindingForPlane (mapplanes[s->planenum].normal, mapplanes[s->planenum].dist);
fprintf (f,"( %i %i %i ) ", (int)w->p[0][0], (int)w->p[0][1], (int)w->p[0][2]);
fprintf (f,"( %i %i %i ) ", (int)w->p[1][0], (int)w->p[1][1], (int)w->p[1][2]);
fprintf (f,"( %i %i %i ) ", (int)w->p[2][0], (int)w->p[2][1], (int)w->p[2][2]);
fprintf (f, "%s 0 0 0 1 1\n", texinfo[s->texinfo].texture);
FreeWinding (w);
}
fprintf (f, "}\n");
}
fprintf (f, "}\n");
fclose (f);
}
/*
==================
BrushGE
Returns true if b1 is allowed to bite b2
==================
*/
qboolean BrushGE (bspbrush_t *b1, bspbrush_t *b2)
{
// detail brushes never bite structural brushes
if ( (b1->original->contents & CONTENTS_DETAIL)
&& !(b2->original->contents & CONTENTS_DETAIL) )
return false;
if (b1->original->contents & CONTENTS_SOLID)
return true;
return false;
}
/*
=================
ChopBrushes
Carves any intersecting solid brushes into the minimum number
of non-intersecting brushes.
=================
*/
bspbrush_t *ChopBrushes (bspbrush_t *head)
{
bspbrush_t *b1, *b2, *next;
bspbrush_t *tail;
bspbrush_t *keep;
bspbrush_t *sub, *sub2;
int c1, c2;
Sys_FPrintf( SYS_VRB, "---- ChopBrushes ----\n");
Sys_FPrintf( SYS_VRB, "original brushes: %i\n", CountBrushList (head));
#if 0
if (startbrush == 0)
WriteBrushList ("before.gl", head, false);
#endif
keep = NULL;
newlist:
// find tail
if (!head)
return NULL;
for (tail=head ; tail->next ; tail=tail->next)
;
for (b1=head ; b1 ; b1=next)
{
next = b1->next;
for (b2=b1->next ; b2 ; b2 = b2->next)
{
if (BrushesDisjoint (b1, b2))
continue;
sub = NULL;
sub2 = NULL;
c1 = 999999;
c2 = 999999;
if ( BrushGE (b2, b1) )
{
sub = SubtractBrush (b1, b2);
if (sub == b1)
continue; // didn't really intersect
if (!sub)
{ // b1 is swallowed by b2
head = CullList (b1, b1);
goto newlist;
}
c1 = CountBrushList (sub);
}
if ( BrushGE (b1, b2) )
{
sub2 = SubtractBrush (b2, b1);
if (sub2 == b2)
continue; // didn't really intersect
if (!sub2)
{ // b2 is swallowed by b1
FreeBrushList (sub);
head = CullList (b1, b2);
goto newlist;
}
c2 = CountBrushList (sub2);
}
if (!sub && !sub2)
continue; // neither one can bite
// only accept if it didn't fragment
// (commening this out allows full fragmentation)
if (c1 > 1 && c2 > 1)
{
if (sub2)
FreeBrushList (sub2);
if (sub)
FreeBrushList (sub);
continue;
}
if (c1 < c2)
{
if (sub2)
FreeBrushList (sub2);
tail = AddBrushListToTail (sub, tail);
head = CullList (b1, b1);
goto newlist;
}
else
{
if (sub)
FreeBrushList (sub);
tail = AddBrushListToTail (sub2, tail);
head = CullList (b1, b2);
goto newlist;
}
}
if (!b2)
{ // b1 is no longer intersecting anything, so keep it
b1->next = keep;
keep = b1;
}
}
Sys_FPrintf( SYS_VRB, "output brushes: %i\n", CountBrushList (keep));
#if 0
{
WriteBrushList ("after.gl", keep, false);
WriteBrushMap ("after.map", keep);
}
#endif
return keep;
}
/*
=================
InitialBrushList
=================
*/
bspbrush_t *InitialBrushList (bspbrush_t *list)
{
bspbrush_t *b;
bspbrush_t *out, *newb;
int i;
// only return brushes that have visible faces
out = NULL;
for (b=list ; b ; b=b->next)
{
#if 0
for (i=0 ; i<b->numsides ; i++)
if (b->sides[i].visible)
break;
if (i == b->numsides)
continue;
#endif
newb = CopyBrush (b);
newb->next = out;
out = newb;
// clear visible, so it must be set by MarkVisibleFaces_r
// to be used in the optimized list
for (i=0 ; i<b->numsides ; i++)
{
newb->sides[i].original = &b->sides[i];
// newb->sides[i].visible = true;
b->sides[i].visible = false;
}
}
return out;
}
/*
=================
OptimizedBrushList
=================
*/
bspbrush_t *OptimizedBrushList (bspbrush_t *list)
{
bspbrush_t *b;
bspbrush_t *out, *newb;
int i;
// only return brushes that have visible faces
out = NULL;
for (b=list ; b ; b=b->next)
{
for (i=0 ; i<b->numsides ; i++)
if (b->sides[i].visible)
break;
if (i == b->numsides)
continue;
newb = CopyBrush (b);
newb->next = out;
out = newb;
}
// WriteBrushList ("vis.gl", out, true);
return out;
}