gtkradiant/tools/quake2/common/polylib.c
2012-03-17 15:01:54 -05:00

649 lines
13 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 "cmdlib.h"
#include "inout.h"
#include "mathlib.h"
#include "polylib.h"
extern int numthreads;
// counters are only bumped when running single threaded,
// because they are an awefull coherence problem
int c_active_windings;
int c_peak_windings;
int c_winding_allocs;
int c_winding_points;
#define BOGUS_RANGE 8192
void pw( winding_t *w ){
int i;
for ( i = 0 ; i < w->numpoints ; i++ )
printf( "(%5.1f, %5.1f, %5.1f)\n",w->p[i][0], w->p[i][1],w->p[i][2] );
}
/*
=============
AllocWinding
=============
*/
winding_t *AllocWinding( int points ){
winding_t *w;
int s;
if ( numthreads == 1 ) {
c_winding_allocs++;
c_winding_points += points;
c_active_windings++;
if ( c_active_windings > c_peak_windings ) {
c_peak_windings = c_active_windings;
}
}
s = sizeof( vec_t ) * 3 * points + sizeof( int );
w = malloc( s );
memset( w, 0, s );
return w;
}
void FreeWinding( winding_t *w ){
if ( *(unsigned *)w == 0xdeaddead ) {
Error( "FreeWinding: freed a freed winding" );
}
*(unsigned *)w = 0xdeaddead;
if ( numthreads == 1 ) {
c_active_windings--;
}
free( w );
}
/*
============
RemoveColinearPoints
============
*/
int c_removed;
void RemoveColinearPoints( winding_t *w ){
int i, j, k;
vec3_t v1, v2;
int nump;
vec3_t p[MAX_POINTS_ON_WINDING];
nump = 0;
for ( i = 0 ; i < w->numpoints ; i++ )
{
j = ( i + 1 ) % w->numpoints;
k = ( i + w->numpoints - 1 ) % w->numpoints;
VectorSubtract( w->p[j], w->p[i], v1 );
VectorSubtract( w->p[i], w->p[k], v2 );
VectorNormalize( v1,v1 );
VectorNormalize( v2,v2 );
if ( DotProduct( v1, v2 ) < 0.999 ) {
VectorCopy( w->p[i], p[nump] );
nump++;
}
}
if ( nump == w->numpoints ) {
return;
}
if ( numthreads == 1 ) {
c_removed += w->numpoints - nump;
}
w->numpoints = nump;
memcpy( w->p, p, nump * sizeof( p[0] ) );
}
/*
============
WindingPlane
============
*/
void WindingPlane( winding_t *w, vec3_t normal, vec_t *dist ){
vec3_t v1, v2;
VectorSubtract( w->p[1], w->p[0], v1 );
VectorSubtract( w->p[2], w->p[0], v2 );
CrossProduct( v2, v1, normal );
VectorNormalize( normal, normal );
*dist = DotProduct( w->p[0], normal );
}
/*
=============
WindingArea
=============
*/
vec_t WindingArea( winding_t *w ){
int i;
vec3_t d1, d2, cross;
vec_t total;
total = 0;
for ( i = 2 ; i < w->numpoints ; i++ )
{
VectorSubtract( w->p[i - 1], w->p[0], d1 );
VectorSubtract( w->p[i], w->p[0], d2 );
CrossProduct( d1, d2, cross );
total += 0.5 * VectorLength( cross );
}
return total;
}
void WindingBounds( winding_t *w, vec3_t mins, vec3_t maxs ){
vec_t v;
int i,j;
mins[0] = mins[1] = mins[2] = 99999;
maxs[0] = maxs[1] = maxs[2] = -99999;
for ( i = 0 ; i < w->numpoints ; i++ )
{
for ( j = 0 ; j < 3 ; j++ )
{
v = w->p[i][j];
if ( v < mins[j] ) {
mins[j] = v;
}
if ( v > maxs[j] ) {
maxs[j] = v;
}
}
}
}
/*
=============
WindingCenter
=============
*/
void WindingCenter( winding_t *w, vec3_t center ){
int i;
float scale;
VectorCopy( vec3_origin, center );
for ( i = 0 ; i < w->numpoints ; i++ )
VectorAdd( w->p[i], center, center );
scale = 1.0 / w->numpoints;
VectorScale( center, scale, center );
}
/*
=================
BaseWindingForPlane
=================
*/
winding_t *BaseWindingForPlane( vec3_t normal, vec_t dist ){
int i, x;
vec_t max, v;
vec3_t org, vright, vup;
winding_t *w;
// find the major axis
max = -BOGUS_RANGE;
x = -1;
for ( i = 0 ; i < 3; i++ )
{
v = fabs( normal[i] );
if ( v > max ) {
x = i;
max = v;
}
}
if ( x == -1 ) {
Error( "BaseWindingForPlane: no axis found" );
}
VectorCopy( vec3_origin, vup );
switch ( x )
{
case 0:
case 1:
vup[2] = 1;
break;
case 2:
vup[0] = 1;
break;
}
v = DotProduct( vup, normal );
VectorMA( vup, -v, normal, vup );
VectorNormalize( vup, vup );
VectorScale( normal, dist, org );
CrossProduct( vup, normal, vright );
VectorScale( vup, 8192, vup );
VectorScale( vright, 8192, vright );
// project a really big axis aligned box onto the plane
w = AllocWinding( 4 );
VectorSubtract( org, vright, w->p[0] );
VectorAdd( w->p[0], vup, w->p[0] );
VectorAdd( org, vright, w->p[1] );
VectorAdd( w->p[1], vup, w->p[1] );
VectorAdd( org, vright, w->p[2] );
VectorSubtract( w->p[2], vup, w->p[2] );
VectorSubtract( org, vright, w->p[3] );
VectorSubtract( w->p[3], vup, w->p[3] );
w->numpoints = 4;
return w;
}
/*
==================
CopyWinding
==================
*/
winding_t *CopyWinding( winding_t *w ){
int size;
winding_t *c;
c = AllocWinding( w->numpoints );
size = (int)( (winding_t *)0 )->p[w->numpoints];
memcpy( c, w, size );
return c;
}
/*
==================
ReverseWinding
==================
*/
winding_t *ReverseWinding( winding_t *w ){
int i;
winding_t *c;
c = AllocWinding( w->numpoints );
for ( i = 0 ; i < w->numpoints ; i++ )
{
VectorCopy( w->p[w->numpoints - 1 - i], c->p[i] );
}
c->numpoints = w->numpoints;
return c;
}
/*
=============
ClipWindingEpsilon
=============
*/
void ClipWindingEpsilon( winding_t *in, vec3_t normal, vec_t dist,
vec_t epsilon, winding_t **front, winding_t **back ){
vec_t dists[MAX_POINTS_ON_WINDING + 4];
int sides[MAX_POINTS_ON_WINDING + 4];
int counts[3];
static vec_t dot; // VC 4.2 optimizer bug if not static
int i, j;
vec_t *p1, *p2;
vec3_t mid;
winding_t *f, *b;
int maxpts;
counts[0] = counts[1] = counts[2] = 0;
// determine sides for each point
for ( i = 0 ; i < in->numpoints ; i++ )
{
dot = DotProduct( in->p[i], normal );
dot -= dist;
dists[i] = dot;
if ( dot > epsilon ) {
sides[i] = SIDE_FRONT;
}
else if ( dot < -epsilon ) {
sides[i] = SIDE_BACK;
}
else
{
sides[i] = SIDE_ON;
}
counts[sides[i]]++;
}
sides[i] = sides[0];
dists[i] = dists[0];
*front = *back = NULL;
if ( !counts[0] ) {
*back = CopyWinding( in );
return;
}
if ( !counts[1] ) {
*front = CopyWinding( in );
return;
}
maxpts = in->numpoints + 4; // cant use counts[0]+2 because
// of fp grouping errors
*front = f = AllocWinding( maxpts );
*back = b = AllocWinding( maxpts );
for ( i = 0 ; i < in->numpoints ; i++ )
{
p1 = in->p[i];
if ( sides[i] == SIDE_ON ) {
VectorCopy( p1, f->p[f->numpoints] );
f->numpoints++;
VectorCopy( p1, b->p[b->numpoints] );
b->numpoints++;
continue;
}
if ( sides[i] == SIDE_FRONT ) {
VectorCopy( p1, f->p[f->numpoints] );
f->numpoints++;
}
if ( sides[i] == SIDE_BACK ) {
VectorCopy( p1, b->p[b->numpoints] );
b->numpoints++;
}
if ( sides[i + 1] == SIDE_ON || sides[i + 1] == sides[i] ) {
continue;
}
// generate a split point
p2 = in->p[( 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 ( normal[j] == 1 ) {
mid[j] = dist;
}
else if ( normal[j] == -1 ) {
mid[j] = -dist;
}
else{
mid[j] = p1[j] + dot * ( p2[j] - p1[j] );
}
}
VectorCopy( mid, f->p[f->numpoints] );
f->numpoints++;
VectorCopy( mid, b->p[b->numpoints] );
b->numpoints++;
}
if ( f->numpoints > maxpts || b->numpoints > maxpts ) {
Error( "ClipWinding: points exceeded estimate" );
}
if ( f->numpoints > MAX_POINTS_ON_WINDING || b->numpoints > MAX_POINTS_ON_WINDING ) {
Error( "ClipWinding: MAX_POINTS_ON_WINDING" );
}
}
/*
=============
ChopWindingInPlace
=============
*/
void ChopWindingInPlace( winding_t **inout, vec3_t normal, vec_t dist, vec_t epsilon ){
winding_t *in;
vec_t dists[MAX_POINTS_ON_WINDING + 4];
int sides[MAX_POINTS_ON_WINDING + 4];
int counts[3];
static vec_t dot; // VC 4.2 optimizer bug if not static
int i, j;
vec_t *p1, *p2;
vec3_t mid;
winding_t *f;
int maxpts;
in = *inout;
counts[0] = counts[1] = counts[2] = 0;
// determine sides for each point
for ( i = 0 ; i < in->numpoints ; i++ )
{
dot = DotProduct( in->p[i], normal );
dot -= dist;
dists[i] = dot;
if ( dot > epsilon ) {
sides[i] = SIDE_FRONT;
}
else if ( dot < -epsilon ) {
sides[i] = SIDE_BACK;
}
else
{
sides[i] = SIDE_ON;
}
counts[sides[i]]++;
}
sides[i] = sides[0];
dists[i] = dists[0];
if ( !counts[0] ) {
FreeWinding( in );
*inout = NULL;
return;
}
if ( !counts[1] ) {
return; // inout stays the same
}
maxpts = in->numpoints + 4; // cant use counts[0]+2 because
// of fp grouping errors
f = AllocWinding( maxpts );
for ( i = 0 ; i < in->numpoints ; i++ )
{
p1 = in->p[i];
if ( sides[i] == SIDE_ON ) {
VectorCopy( p1, f->p[f->numpoints] );
f->numpoints++;
continue;
}
if ( sides[i] == SIDE_FRONT ) {
VectorCopy( p1, f->p[f->numpoints] );
f->numpoints++;
}
if ( sides[i + 1] == SIDE_ON || sides[i + 1] == sides[i] ) {
continue;
}
// generate a split point
p2 = in->p[( 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 ( normal[j] == 1 ) {
mid[j] = dist;
}
else if ( normal[j] == -1 ) {
mid[j] = -dist;
}
else{
mid[j] = p1[j] + dot * ( p2[j] - p1[j] );
}
}
VectorCopy( mid, f->p[f->numpoints] );
f->numpoints++;
}
if ( f->numpoints > maxpts ) {
Error( "ClipWinding: points exceeded estimate" );
}
if ( f->numpoints > MAX_POINTS_ON_WINDING ) {
Error( "ClipWinding: MAX_POINTS_ON_WINDING" );
}
FreeWinding( in );
*inout = f;
}
/*
=================
ChopWinding
Returns the fragment of in that is on the front side
of the cliping plane. The original is freed.
=================
*/
winding_t *ChopWinding( winding_t *in, vec3_t normal, vec_t dist ){
winding_t *f, *b;
ClipWindingEpsilon( in, normal, dist, ON_EPSILON, &f, &b );
FreeWinding( in );
if ( b ) {
FreeWinding( b );
}
return f;
}
/*
=================
CheckWinding
=================
*/
void CheckWinding( winding_t *w ){
int i, j;
vec_t *p1, *p2;
vec_t d, edgedist;
vec3_t dir, edgenormal, facenormal;
vec_t area;
vec_t facedist;
if ( w->numpoints < 3 ) {
Error( "CheckWinding: %i points",w->numpoints );
}
area = WindingArea( w );
if ( area < 1 ) {
Error( "CheckWinding: %f area", area );
}
WindingPlane( w, facenormal, &facedist );
for ( i = 0 ; i < w->numpoints ; i++ )
{
p1 = w->p[i];
for ( j = 0 ; j < 3 ; j++ )
if ( p1[j] > BOGUS_RANGE || p1[j] < -BOGUS_RANGE ) {
Error( "CheckFace: BUGUS_RANGE: %f",p1[j] );
}
j = i + 1 == w->numpoints ? 0 : i + 1;
// check the point is on the face plane
d = DotProduct( p1, facenormal ) - facedist;
if ( d < -ON_EPSILON || d > ON_EPSILON ) {
Error( "CheckWinding: point off plane" );
}
// check the edge isnt degenerate
p2 = w->p[j];
VectorSubtract( p2, p1, dir );
if ( VectorLength( dir ) < ON_EPSILON ) {
Error( "CheckWinding: degenerate edge" );
}
CrossProduct( facenormal, dir, edgenormal );
VectorNormalize( edgenormal, edgenormal );
edgedist = DotProduct( p1, edgenormal );
edgedist += ON_EPSILON;
// all other points must be on front side
for ( j = 0 ; j < w->numpoints ; j++ )
{
if ( j == i ) {
continue;
}
d = DotProduct( w->p[j], edgenormal );
if ( d > edgedist ) {
Error( "CheckWinding: non-convex" );
}
}
}
}
/*
============
WindingOnPlaneSide
============
*/
int WindingOnPlaneSide( winding_t *w, vec3_t normal, vec_t dist ){
qboolean front, back;
int i;
vec_t d;
front = false;
back = false;
for ( i = 0 ; i < w->numpoints ; i++ )
{
d = DotProduct( w->p[i], normal ) - dist;
if ( d < -ON_EPSILON ) {
if ( front ) {
return SIDE_CROSS;
}
back = true;
continue;
}
if ( d > ON_EPSILON ) {
if ( back ) {
return SIDE_CROSS;
}
front = true;
continue;
}
}
if ( back ) {
return SIDE_BACK;
}
if ( front ) {
return SIDE_FRONT;
}
return SIDE_ON;
}