dhewm3-sdk/idlib/geometry/Winding.cpp
dhewg afebd7e1e5 Untangle the epic precompiled.h mess
Don't include the lazy precompiled.h everywhere, only what's
required for the compilation unit.
platform.h needs to be included instead to provide all essential
defines and types.
All includes use the relative path to the neo or the game
specific root.
Move all idlib related includes from idlib/Lib.h to precompiled.h.
precompiled.h still exists for the MFC stuff in tools/.
Add some missing header guards.
2018-08-20 01:46:28 +02:00

1603 lines
34 KiB
C++

/*
===========================================================================
Doom 3 GPL Source Code
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 GPL Source Code ("Doom 3 Source Code").
Doom 3 Source Code 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 3 of the License, or
(at your option) any later version.
Doom 3 Source Code 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 Doom 3 Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
#include "sys/platform.h"
#include "idlib/math/Pluecker.h"
#include "framework/Common.h"
#include "idlib/geometry/Winding.h"
//===============================================================
//
// idWinding
//
//===============================================================
/*
=============
idWinding::ReAllocate
=============
*/
bool idWinding::ReAllocate( int n, bool keep ) {
idVec5 *oldP;
oldP = p;
n = (n+3) & ~3; // align up to multiple of four
p = new idVec5[n];
if ( oldP ) {
if ( keep ) {
memcpy( p, oldP, numPoints * sizeof(p[0]) );
}
delete[] oldP;
}
allocedSize = n;
return true;
}
/*
=============
idWinding::BaseForPlane
=============
*/
void idWinding::BaseForPlane( const idVec3 &normal, const float dist ) {
idVec3 org, vright, vup;
org = normal * dist;
normal.NormalVectors( vup, vright );
vup *= MAX_WORLD_SIZE;
vright *= MAX_WORLD_SIZE;
EnsureAlloced( 4 );
numPoints = 4;
p[0].ToVec3() = org - vright + vup;
p[0].s = p[0].t = 0.0f;
p[1].ToVec3() = org + vright + vup;
p[1].s = p[1].t = 0.0f;
p[2].ToVec3() = org + vright - vup;
p[2].s = p[2].t = 0.0f;
p[3].ToVec3() = org - vright - vup;
p[3].s = p[3].t = 0.0f;
}
/*
=============
idWinding::Split
=============
*/
int idWinding::Split( const idPlane &plane, const float epsilon, idWinding **front, idWinding **back ) const {
float * dists;
byte * sides;
int counts[3];
float dot;
int i, j;
const idVec5 * p1, *p2;
idVec5 mid;
idWinding * f, *b;
int maxpts;
assert( this );
dists = (float *) _alloca( (numPoints+4) * sizeof( float ) );
sides = (byte *) _alloca( (numPoints+4) * sizeof( byte ) );
counts[0] = counts[1] = counts[2] = 0;
// determine sides for each point
for ( i = 0; i < numPoints; i++ ) {
dists[i] = dot = plane.Distance( p[i].ToVec3() );
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 coplanar, put on the front side if the normals match
if ( !counts[SIDE_FRONT] && !counts[SIDE_BACK] ) {
idPlane windingPlane;
GetPlane( windingPlane );
if ( windingPlane.Normal() * plane.Normal() > 0.0f ) {
*front = Copy();
return SIDE_FRONT;
} else {
*back = Copy();
return SIDE_BACK;
}
}
// if nothing at the front of the clipping plane
if ( !counts[SIDE_FRONT] ) {
*back = Copy();
return SIDE_BACK;
}
// if nothing at the back of the clipping plane
if ( !counts[SIDE_BACK] ) {
*front = Copy();
return SIDE_FRONT;
}
maxpts = numPoints+4; // cant use counts[0]+2 because of fp grouping errors
*front = f = new idWinding(maxpts);
*back = b = new idWinding(maxpts);
for (i = 0; i < numPoints; i++) {
p1 = &p[i];
if ( sides[i] == SIDE_ON ) {
f->p[f->numPoints] = *p1;
f->numPoints++;
b->p[b->numPoints] = *p1;
b->numPoints++;
continue;
}
if ( sides[i] == SIDE_FRONT ) {
f->p[f->numPoints] = *p1;
f->numPoints++;
}
if ( sides[i] == SIDE_BACK ) {
b->p[b->numPoints] = *p1;
b->numPoints++;
}
if ( sides[i+1] == SIDE_ON || sides[i+1] == sides[i] ) {
continue;
}
// generate a split point
p2 = &p[(i+1)%numPoints];
// always calculate the split going from the same side
// or minor epsilon issues can happen
if ( sides[i] == SIDE_FRONT ) {
dot = dists[i] / ( dists[i] - dists[i+1] );
for ( j = 0; j < 3; j++ ) {
// avoid round off error when possible
if ( plane.Normal()[j] == 1.0f ) {
mid[j] = plane.Dist();
} else if ( plane.Normal()[j] == -1.0f ) {
mid[j] = -plane.Dist();
} else {
mid[j] = (*p1)[j] + dot * ( (*p2)[j] - (*p1)[j] );
}
}
mid.s = p1->s + dot * ( p2->s - p1->s );
mid.t = p1->t + dot * ( p2->t - p1->t );
} else {
dot = dists[i+1] / ( dists[i+1] - dists[i] );
for ( j = 0; j < 3; j++ ) {
// avoid round off error when possible
if ( plane.Normal()[j] == 1.0f ) {
mid[j] = plane.Dist();
} else if ( plane.Normal()[j] == -1.0f ) {
mid[j] = -plane.Dist();
} else {
mid[j] = (*p2)[j] + dot * ( (*p1)[j] - (*p2)[j] );
}
}
mid.s = p2->s + dot * ( p1->s - p2->s );
mid.t = p2->t + dot * ( p1->t - p2->t );
}
f->p[f->numPoints] = mid;
f->numPoints++;
b->p[b->numPoints] = mid;
b->numPoints++;
}
if ( f->numPoints > maxpts || b->numPoints > maxpts ) {
idLib::common->FatalError( "idWinding::Split: points exceeded estimate." );
}
return SIDE_CROSS;
}
/*
=============
idWinding::Clip
=============
*/
idWinding *idWinding::Clip( const idPlane &plane, const float epsilon, const bool keepOn ) {
float * dists;
byte * sides;
idVec5 * newPoints;
int newNumPoints;
int counts[3];
float dot;
int i, j;
idVec5 * p1, *p2;
idVec5 mid;
int maxpts;
assert( this );
dists = (float *) _alloca( (numPoints+4) * sizeof( float ) );
sides = (byte *) _alloca( (numPoints+4) * sizeof( byte ) );
counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
// determine sides for each point
for ( i = 0; i < numPoints; i++ ) {
dists[i] = dot = plane.Distance( p[i].ToVec3() );
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 the winding is on the plane and we should keep it
if ( keepOn && !counts[SIDE_FRONT] && !counts[SIDE_BACK] ) {
return this;
}
// if nothing at the front of the clipping plane
if ( !counts[SIDE_FRONT] ) {
delete this;
return NULL;
}
// if nothing at the back of the clipping plane
if ( !counts[SIDE_BACK] ) {
return this;
}
maxpts = numPoints + 4; // cant use counts[0]+2 because of fp grouping errors
newPoints = (idVec5 *) _alloca16( maxpts * sizeof( idVec5 ) );
newNumPoints = 0;
for ( i = 0; i < numPoints; i++ ) {
p1 = &p[i];
if ( newNumPoints+1 > maxpts ) {
return this; // can't split -- fall back to original
}
if ( sides[i] == SIDE_ON ) {
newPoints[newNumPoints] = *p1;
newNumPoints++;
continue;
}
if ( sides[i] == SIDE_FRONT ) {
newPoints[newNumPoints] = *p1;
newNumPoints++;
}
if ( sides[i+1] == SIDE_ON || sides[i+1] == sides[i] ) {
continue;
}
if ( newNumPoints+1 > maxpts ) {
return this; // can't split -- fall back to original
}
// generate a split point
p2 = &p[(i+1)%numPoints];
dot = dists[i] / (dists[i] - dists[i+1]);
for ( j = 0; j < 3; j++ ) {
// avoid round off error when possible
if ( plane.Normal()[j] == 1.0f ) {
mid[j] = plane.Dist();
} else if ( plane.Normal()[j] == -1.0f ) {
mid[j] = -plane.Dist();
} else {
mid[j] = (*p1)[j] + dot * ( (*p2)[j] - (*p1)[j] );
}
}
mid.s = p1->s + dot * ( p2->s - p1->s );
mid.t = p1->t + dot * ( p2->t - p1->t );
newPoints[newNumPoints] = mid;
newNumPoints++;
}
if ( !EnsureAlloced( newNumPoints, false ) ) {
return this;
}
numPoints = newNumPoints;
memcpy( p, newPoints, newNumPoints * sizeof(idVec5) );
return this;
}
/*
=============
idWinding::ClipInPlace
=============
*/
bool idWinding::ClipInPlace( const idPlane &plane, const float epsilon, const bool keepOn ) {
float* dists;
byte * sides;
idVec5 * newPoints;
int newNumPoints;
int counts[3];
float dot;
int i, j;
idVec5 * p1, *p2;
idVec5 mid;
int maxpts;
assert( this );
dists = (float *) _alloca( (numPoints+4) * sizeof( float ) );
sides = (byte *) _alloca( (numPoints+4) * sizeof( byte ) );
counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
// determine sides for each point
for ( i = 0; i < numPoints; i++ ) {
dists[i] = dot = plane.Distance( p[i].ToVec3() );
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 the winding is on the plane and we should keep it
if ( keepOn && !counts[SIDE_FRONT] && !counts[SIDE_BACK] ) {
return true;
}
// if nothing at the front of the clipping plane
if ( !counts[SIDE_FRONT] ) {
numPoints = 0;
return false;
}
// if nothing at the back of the clipping plane
if ( !counts[SIDE_BACK] ) {
return true;
}
maxpts = numPoints + 4; // cant use counts[0]+2 because of fp grouping errors
newPoints = (idVec5 *) _alloca16( maxpts * sizeof( idVec5 ) );
newNumPoints = 0;
for ( i = 0; i < numPoints; i++ ) {
p1 = &p[i];
if ( newNumPoints+1 > maxpts ) {
return true; // can't split -- fall back to original
}
if ( sides[i] == SIDE_ON ) {
newPoints[newNumPoints] = *p1;
newNumPoints++;
continue;
}
if ( sides[i] == SIDE_FRONT ) {
newPoints[newNumPoints] = *p1;
newNumPoints++;
}
if ( sides[i+1] == SIDE_ON || sides[i+1] == sides[i] ) {
continue;
}
if ( newNumPoints+1 > maxpts ) {
return true; // can't split -- fall back to original
}
// generate a split point
p2 = &p[(i+1)%numPoints];
dot = dists[i] / (dists[i] - dists[i+1]);
for ( j = 0; j < 3; j++ ) {
// avoid round off error when possible
if ( plane.Normal()[j] == 1.0f ) {
mid[j] = plane.Dist();
} else if ( plane.Normal()[j] == -1.0f ) {
mid[j] = -plane.Dist();
} else {
mid[j] = (*p1)[j] + dot * ( (*p2)[j] - (*p1)[j] );
}
}
mid.s = p1->s + dot * ( p2->s - p1->s );
mid.t = p1->t + dot * ( p2->t - p1->t );
newPoints[newNumPoints] = mid;
newNumPoints++;
}
if ( !EnsureAlloced( newNumPoints, false ) ) {
return true;
}
numPoints = newNumPoints;
memcpy( p, newPoints, newNumPoints * sizeof(idVec5) );
return true;
}
/*
=============
idWinding::Copy
=============
*/
idWinding *idWinding::Copy( void ) const {
idWinding *w;
w = new idWinding( numPoints );
w->numPoints = numPoints;
memcpy( w->p, p, numPoints * sizeof(p[0]) );
return w;
}
/*
=============
idWinding::Reverse
=============
*/
idWinding *idWinding::Reverse( void ) const {
idWinding *w;
int i;
w = new idWinding( numPoints );
w->numPoints = numPoints;
for ( i = 0; i < numPoints; i++ ) {
w->p[ numPoints - i - 1 ] = p[i];
}
return w;
}
/*
=============
idWinding::ReverseSelf
=============
*/
void idWinding::ReverseSelf( void ) {
idVec5 v;
int i;
for ( i = 0; i < (numPoints>>1); i++ ) {
v = p[i];
p[i] = p[numPoints - i - 1];
p[numPoints - i - 1] = v;
}
}
/*
=============
idWinding::Check
=============
*/
bool idWinding::Check( bool print ) const {
int i, j;
float d, edgedist;
idVec3 dir, edgenormal;
float area;
idPlane plane;
if ( numPoints < 3 ) {
if ( print ) {
idLib::common->Printf( "idWinding::Check: only %i points.", numPoints );
}
return false;
}
area = GetArea();
if ( area < 1.0f ) {
if ( print ) {
idLib::common->Printf( "idWinding::Check: tiny area: %f", area );
}
return false;
}
GetPlane( plane );
for ( i = 0; i < numPoints; i++ ) {
const idVec3 &p1 = p[i].ToVec3();
// check if the winding is huge
for ( j = 0; j < 3; j++ ) {
if ( p1[j] >= MAX_WORLD_COORD || p1[j] <= MIN_WORLD_COORD ) {
if ( print ) {
idLib::common->Printf( "idWinding::Check: point %d outside world %c-axis: %f", i, 'X'+j, p1[j] );
}
return false;
}
}
j = i + 1 == numPoints ? 0 : i + 1;
// check if the point is on the face plane
d = p1 * plane.Normal() + plane[3];
if ( d < -ON_EPSILON || d > ON_EPSILON ) {
if ( print ) {
idLib::common->Printf( "idWinding::Check: point %d off plane.", i );
}
return false;
}
// check if the edge isn't degenerate
const idVec3 &p2 = p[j].ToVec3();
dir = p2 - p1;
if ( dir.Length() < ON_EPSILON) {
if ( print ) {
idLib::common->Printf( "idWinding::Check: edge %d is degenerate.", i );
}
return false;
}
// check if the winding is convex
edgenormal = plane.Normal().Cross( dir );
edgenormal.Normalize();
edgedist = p1 * edgenormal;
edgedist += ON_EPSILON;
// all other points must be on front side
for ( j = 0; j < numPoints; j++ ) {
if ( j == i ) {
continue;
}
d = p[j].ToVec3() * edgenormal;
if ( d > edgedist ) {
if ( print ) {
idLib::common->Printf( "idWinding::Check: non-convex." );
}
return false;
}
}
}
return true;
}
/*
=============
idWinding::GetArea
=============
*/
float idWinding::GetArea( void ) const {
int i;
idVec3 d1, d2, cross;
float total;
total = 0.0f;
for ( i = 2; i < numPoints; i++ ) {
d1 = p[i-1].ToVec3() - p[0].ToVec3();
d2 = p[i].ToVec3() - p[0].ToVec3();
cross = d1.Cross( d2 );
total += cross.Length();
}
return total * 0.5f;
}
/*
=============
idWinding::GetRadius
=============
*/
float idWinding::GetRadius( const idVec3 &center ) const {
int i;
float radius, r;
idVec3 dir;
radius = 0.0f;
for ( i = 0; i < numPoints; i++ ) {
dir = p[i].ToVec3() - center;
r = dir * dir;
if ( r > radius ) {
radius = r;
}
}
return idMath::Sqrt( radius );
}
/*
=============
idWinding::GetCenter
=============
*/
idVec3 idWinding::GetCenter( void ) const {
int i;
idVec3 center;
center.Zero();
for ( i = 0; i < numPoints; i++ ) {
center += p[i].ToVec3();
}
center *= ( 1.0f / numPoints );
return center;
}
/*
=============
idWinding::GetPlane
=============
*/
void idWinding::GetPlane( idVec3 &normal, float &dist ) const {
idVec3 v1, v2, center;
if ( numPoints < 3 ) {
normal.Zero();
dist = 0.0f;
return;
}
center = GetCenter();
v1 = p[0].ToVec3() - center;
v2 = p[1].ToVec3() - center;
normal = v2.Cross( v1 );
normal.Normalize();
dist = p[0].ToVec3() * normal;
}
/*
=============
idWinding::GetPlane
=============
*/
void idWinding::GetPlane( idPlane &plane ) const {
idVec3 v1, v2;
idVec3 center;
if ( numPoints < 3 ) {
plane.Zero();
return;
}
center = GetCenter();
v1 = p[0].ToVec3() - center;
v2 = p[1].ToVec3() - center;
plane.SetNormal( v2.Cross( v1 ) );
plane.Normalize();
plane.FitThroughPoint( p[0].ToVec3() );
}
/*
=============
idWinding::GetBounds
=============
*/
void idWinding::GetBounds( idBounds &bounds ) const {
int i;
if ( !numPoints ) {
bounds.Clear();
return;
}
bounds[0] = bounds[1] = p[0].ToVec3();
for ( i = 1; i < numPoints; i++ ) {
if ( p[i].x < bounds[0].x ) {
bounds[0].x = p[i].x;
} else if ( p[i].x > bounds[1].x ) {
bounds[1].x = p[i].x;
}
if ( p[i].y < bounds[0].y ) {
bounds[0].y = p[i].y;
} else if ( p[i].y > bounds[1].y ) {
bounds[1].y = p[i].y;
}
if ( p[i].z < bounds[0].z ) {
bounds[0].z = p[i].z;
} else if ( p[i].z > bounds[1].z ) {
bounds[1].z = p[i].z;
}
}
}
/*
=============
idWinding::RemoveEqualPoints
=============
*/
void idWinding::RemoveEqualPoints( const float epsilon ) {
int i, j;
for ( i = 0; i < numPoints; i++ ) {
if ( (p[i].ToVec3() - p[(i+numPoints-1)%numPoints].ToVec3()).LengthSqr() >= Square( epsilon ) ) {
continue;
}
numPoints--;
for ( j = i; j < numPoints; j++ ) {
p[j] = p[j+1];
}
i--;
}
}
/*
=============
idWinding::RemoveColinearPoints
=============
*/
void idWinding::RemoveColinearPoints( const idVec3 &normal, const float epsilon ) {
int i, j;
idVec3 edgeNormal;
float dist;
if ( numPoints <= 3 ) {
return;
}
for ( i = 0; i < numPoints; i++ ) {
// create plane through edge orthogonal to winding plane
edgeNormal = (p[i].ToVec3() - p[(i+numPoints-1)%numPoints].ToVec3()).Cross( normal );
edgeNormal.Normalize();
dist = edgeNormal * p[i].ToVec3();
if ( idMath::Fabs( edgeNormal * p[(i+1)%numPoints].ToVec3() - dist ) > epsilon ) {
continue;
}
numPoints--;
for ( j = i; j < numPoints; j++ ) {
p[j] = p[j+1];
}
i--;
}
}
/*
=============
idWinding::AddToConvexHull
Adds the given winding to the convex hull.
Assumes the current winding already is a convex hull with three or more points.
=============
*/
void idWinding::AddToConvexHull( const idWinding *winding, const idVec3 &normal, const float epsilon ) {
int i, j, k;
idVec3 dir;
float d;
int maxPts;
idVec3 * hullDirs;
bool * hullSide;
bool outside;
int numNewHullPoints;
idVec5 * newHullPoints;
if ( !winding ) {
return;
}
maxPts = this->numPoints + winding->numPoints;
if ( !this->EnsureAlloced( maxPts, true ) ) {
return;
}
newHullPoints = (idVec5 *) _alloca( maxPts * sizeof( idVec5 ) );
hullDirs = (idVec3 *) _alloca( maxPts * sizeof( idVec3 ) );
hullSide = (bool *) _alloca( maxPts * sizeof( bool ) );
for ( i = 0; i < winding->numPoints; i++ ) {
const idVec5 &p1 = winding->p[i];
// calculate hull edge vectors
for ( j = 0; j < this->numPoints; j++ ) {
dir = this->p[ (j + 1) % this->numPoints ].ToVec3() - this->p[ j ].ToVec3();
dir.Normalize();
hullDirs[j] = normal.Cross( dir );
}
// calculate side for each hull edge
outside = false;
for ( j = 0; j < this->numPoints; j++ ) {
dir = p1.ToVec3() - this->p[j].ToVec3();
d = dir * hullDirs[j];
if ( d >= epsilon ) {
outside = true;
}
if ( d >= -epsilon ) {
hullSide[j] = true;
} else {
hullSide[j] = false;
}
}
// if the point is effectively inside, do nothing
if ( !outside ) {
continue;
}
// find the back side to front side transition
for ( j = 0; j < this->numPoints; j++ ) {
if ( !hullSide[ j ] && hullSide[ (j + 1) % this->numPoints ] ) {
break;
}
}
if ( j >= this->numPoints ) {
continue;
}
// insert the point here
newHullPoints[0] = p1;
numNewHullPoints = 1;
// copy over all points that aren't double fronts
j = (j+1) % this->numPoints;
for ( k = 0; k < this->numPoints; k++ ) {
if ( hullSide[ (j+k) % this->numPoints ] && hullSide[ (j+k+1) % this->numPoints ] ) {
continue;
}
newHullPoints[numNewHullPoints] = this->p[ (j+k+1) % this->numPoints ];
numNewHullPoints++;
}
this->numPoints = numNewHullPoints;
memcpy( this->p, newHullPoints, numNewHullPoints * sizeof(idVec5) );
}
}
/*
=============
idWinding::AddToConvexHull
Add a point to the convex hull.
The current winding must be convex but may be degenerate and can have less than three points.
=============
*/
void idWinding::AddToConvexHull( const idVec3 &point, const idVec3 &normal, const float epsilon ) {
int j, k, numHullPoints;
idVec3 dir;
float d;
idVec3 * hullDirs;
bool * hullSide;
idVec5 * hullPoints;
bool outside;
switch( numPoints ) {
case 0: {
p[0] = point;
numPoints++;
return;
}
case 1: {
// don't add the same point second
if ( p[0].ToVec3().Compare( point, epsilon ) ) {
return;
}
p[1].ToVec3() = point;
numPoints++;
return;
}
case 2: {
// don't add a point if it already exists
if ( p[0].ToVec3().Compare( point, epsilon ) || p[1].ToVec3().Compare( point, epsilon ) ) {
return;
}
// if only two points make sure we have the right ordering according to the normal
dir = point - p[0].ToVec3();
dir = dir.Cross( p[1].ToVec3() - p[0].ToVec3() );
if ( dir[0] == 0.0f && dir[1] == 0.0f && dir[2] == 0.0f ) {
// points don't make a plane
return;
}
if ( dir * normal > 0.0f ) {
p[2].ToVec3() = point;
}
else {
p[2] = p[1];
p[1].ToVec3() = point;
}
numPoints++;
return;
}
}
hullDirs = (idVec3 *) _alloca( numPoints * sizeof( idVec3 ) );
hullSide = (bool *) _alloca( numPoints * sizeof( bool ) );
// calculate hull edge vectors
for ( j = 0; j < numPoints; j++ ) {
dir = p[(j + 1) % numPoints].ToVec3() - p[j].ToVec3();
hullDirs[j] = normal.Cross( dir );
}
// calculate side for each hull edge
outside = false;
for ( j = 0; j < numPoints; j++ ) {
dir = point - p[j].ToVec3();
d = dir * hullDirs[j];
if ( d >= epsilon ) {
outside = true;
}
if ( d >= -epsilon ) {
hullSide[j] = true;
} else {
hullSide[j] = false;
}
}
// if the point is effectively inside, do nothing
if ( !outside ) {
return;
}
// find the back side to front side transition
for ( j = 0; j < numPoints; j++ ) {
if ( !hullSide[ j ] && hullSide[ (j + 1) % numPoints ] ) {
break;
}
}
if ( j >= numPoints ) {
return;
}
hullPoints = (idVec5 *) _alloca( (numPoints+1) * sizeof( idVec5 ) );
// insert the point here
hullPoints[0] = point;
numHullPoints = 1;
// copy over all points that aren't double fronts
j = (j+1) % numPoints;
for ( k = 0; k < numPoints; k++ ) {
if ( hullSide[ (j+k) % numPoints ] && hullSide[ (j+k+1) % numPoints ] ) {
continue;
}
hullPoints[numHullPoints] = p[ (j+k+1) % numPoints ];
numHullPoints++;
}
if ( !EnsureAlloced( numHullPoints, false ) ) {
return;
}
numPoints = numHullPoints;
memcpy( p, hullPoints, numHullPoints * sizeof(idVec5) );
}
/*
=============
idWinding::TryMerge
=============
*/
#define CONTINUOUS_EPSILON 0.005f
idWinding *idWinding::TryMerge( const idWinding &w, const idVec3 &planenormal, int keep ) const {
idVec3 *p1, *p2, *p3, *p4, *back;
idWinding *newf;
const idWinding *f1, *f2;
int i, j, k, l;
idVec3 normal, delta;
float dot;
bool keep1, keep2;
f1 = this;
f2 = &w;
//
// find a idLib::common edge
//
p1 = p2 = NULL; // stop compiler warning
j = 0;
for ( i = 0; i < f1->numPoints; i++ ) {
p1 = &f1->p[i].ToVec3();
p2 = &f1->p[(i+1) % f1->numPoints].ToVec3();
for ( j = 0; j < f2->numPoints; j++ ) {
p3 = &f2->p[j].ToVec3();
p4 = &f2->p[(j+1) % f2->numPoints].ToVec3();
for (k = 0; k < 3; k++ ) {
if ( idMath::Fabs((*p1)[k] - (*p4)[k]) > 0.1f ) {
break;
}
if ( idMath::Fabs((*p2)[k] - (*p3)[k]) > 0.1f ) {
break;
}
}
if ( k == 3 ) {
break;
}
}
if ( j < f2->numPoints ) {
break;
}
}
if ( i == f1->numPoints ) {
return NULL; // no matching edges
}
//
// check slope of connected lines
// if the slopes are colinear, the point can be removed
//
back = &f1->p[(i+f1->numPoints-1)%f1->numPoints].ToVec3();
delta = (*p1) - (*back);
normal = planenormal.Cross(delta);
normal.Normalize();
back = &f2->p[(j+2)%f2->numPoints].ToVec3();
delta = (*back) - (*p1);
dot = delta * normal;
if ( dot > CONTINUOUS_EPSILON ) {
return NULL; // not a convex polygon
}
keep1 = (bool)(dot < -CONTINUOUS_EPSILON);
back = &f1->p[(i+2)%f1->numPoints].ToVec3();
delta = (*back) - (*p2);
normal = planenormal.Cross( delta );
normal.Normalize();
back = &f2->p[(j+f2->numPoints-1)%f2->numPoints].ToVec3();
delta = (*back) - (*p2);
dot = delta * normal;
if ( dot > CONTINUOUS_EPSILON ) {
return NULL; // not a convex polygon
}
keep2 = (bool)(dot < -CONTINUOUS_EPSILON);
//
// build the new polygon
//
newf = new idWinding( f1->numPoints + f2->numPoints );
// copy first polygon
for ( k = (i+1) % f1->numPoints; k != i; k = (k+1) % f1->numPoints ) {
if ( !keep && k == (i+1) % f1->numPoints && !keep2 ) {
continue;
}
newf->p[newf->numPoints] = f1->p[k];
newf->numPoints++;
}
// copy second polygon
for ( l = (j+1) % f2->numPoints; l != j; l = (l+1) % f2->numPoints ) {
if ( !keep && l == (j+1) % f2->numPoints && !keep1 ) {
continue;
}
newf->p[newf->numPoints] = f2->p[l];
newf->numPoints++;
}
return newf;
}
/*
=============
idWinding::RemovePoint
=============
*/
void idWinding::RemovePoint( int point ) {
if ( point < 0 || point >= numPoints ) {
idLib::common->FatalError( "idWinding::removePoint: point out of range" );
}
if ( point < numPoints - 1) {
memmove(&p[point], &p[point+1], (numPoints - point - 1) * sizeof(p[0]) );
}
numPoints--;
}
/*
=============
idWinding::InsertPoint
=============
*/
void idWinding::InsertPoint( const idVec3 &point, int spot ) {
int i;
if ( spot > numPoints ) {
idLib::common->FatalError( "idWinding::insertPoint: spot > numPoints" );
}
if ( spot < 0 ) {
idLib::common->FatalError( "idWinding::insertPoint: spot < 0" );
}
EnsureAlloced( numPoints+1, true );
for ( i = numPoints; i > spot; i-- ) {
p[i] = p[i-1];
}
p[spot] = point;
numPoints++;
}
/*
=============
idWinding::InsertPointIfOnEdge
=============
*/
bool idWinding::InsertPointIfOnEdge( const idVec3 &point, const idPlane &plane, const float epsilon ) {
int i;
float dist, dot;
idVec3 normal;
// point may not be too far from the winding plane
if ( idMath::Fabs( plane.Distance( point ) ) > epsilon ) {
return false;
}
for ( i = 0; i < numPoints; i++ ) {
// create plane through edge orthogonal to winding plane
normal = (p[(i+1)%numPoints].ToVec3() - p[i].ToVec3()).Cross( plane.Normal() );
normal.Normalize();
dist = normal * p[i].ToVec3();
if ( idMath::Fabs( normal * point - dist ) > epsilon ) {
continue;
}
normal = plane.Normal().Cross( normal );
dot = normal * point;
dist = dot - normal * p[i].ToVec3();
if ( dist < epsilon ) {
// if the winding already has the point
if ( dist > -epsilon ) {
return false;
}
continue;
}
dist = dot - normal * p[(i+1)%numPoints].ToVec3();
if ( dist > -epsilon ) {
// if the winding already has the point
if ( dist < epsilon ) {
return false;
}
continue;
}
InsertPoint( point, i+1 );
return true;
}
return false;
}
/*
=============
idWinding::IsTiny
=============
*/
#define EDGE_LENGTH 0.2f
bool idWinding::IsTiny( void ) const {
int i;
float len;
idVec3 delta;
int edges;
edges = 0;
for ( i = 0; i < numPoints; i++ ) {
delta = p[(i+1)%numPoints].ToVec3() - p[i].ToVec3();
len = delta.Length();
if ( len > EDGE_LENGTH ) {
if ( ++edges == 3 ) {
return false;
}
}
}
return true;
}
/*
=============
idWinding::IsHuge
=============
*/
bool idWinding::IsHuge( void ) const {
int i, j;
for ( i = 0; i < numPoints; i++ ) {
for ( j = 0; j < 3; j++ ) {
if ( p[i][j] <= MIN_WORLD_COORD || p[i][j] >= MAX_WORLD_COORD ) {
return true;
}
}
}
return false;
}
/*
=============
idWinding::Print
=============
*/
void idWinding::Print( void ) const {
int i;
for ( i = 0; i < numPoints; i++ ) {
idLib::common->Printf( "(%5.1f, %5.1f, %5.1f)\n", p[i][0], p[i][1], p[i][2] );
}
}
/*
=============
idWinding::PlaneDistance
=============
*/
float idWinding::PlaneDistance( const idPlane &plane ) const {
int i;
float d, min, max;
min = idMath::INFINITY;
max = -min;
for ( i = 0; i < numPoints; i++ ) {
d = plane.Distance( p[i].ToVec3() );
if ( d < min ) {
min = d;
if ( FLOATSIGNBITSET( min ) & FLOATSIGNBITNOTSET( max ) ) {
return 0.0f;
}
}
if ( d > max ) {
max = d;
if ( FLOATSIGNBITSET( min ) & FLOATSIGNBITNOTSET( max ) ) {
return 0.0f;
}
}
}
if ( FLOATSIGNBITNOTSET( min ) ) {
return min;
}
if ( FLOATSIGNBITSET( max ) ) {
return max;
}
return 0.0f;
}
/*
=============
idWinding::PlaneSide
=============
*/
int idWinding::PlaneSide( const idPlane &plane, const float epsilon ) const {
bool front, back;
int i;
float d;
front = false;
back = false;
for ( i = 0; i < numPoints; i++ ) {
d = plane.Distance( p[i].ToVec3() );
if ( d < -epsilon ) {
if ( front ) {
return SIDE_CROSS;
}
back = true;
continue;
}
else if ( d > epsilon ) {
if ( back ) {
return SIDE_CROSS;
}
front = true;
continue;
}
}
if ( back ) {
return SIDE_BACK;
}
if ( front ) {
return SIDE_FRONT;
}
return SIDE_ON;
}
/*
=============
idWinding::PlanesConcave
=============
*/
#define WCONVEX_EPSILON 0.2f
bool idWinding::PlanesConcave( const idWinding &w2, const idVec3 &normal1, const idVec3 &normal2, float dist1, float dist2 ) const {
int i;
// check if one of the points of winding 1 is at the back of the plane of winding 2
for ( i = 0; i < numPoints; i++ ) {
if ( normal2 * p[i].ToVec3() - dist2 > WCONVEX_EPSILON ) {
return true;
}
}
// check if one of the points of winding 2 is at the back of the plane of winding 1
for ( i = 0; i < w2.numPoints; i++ ) {
if ( normal1 * w2.p[i].ToVec3() - dist1 > WCONVEX_EPSILON ) {
return true;
}
}
return false;
}
/*
=============
idWinding::PointInside
=============
*/
bool idWinding::PointInside( const idVec3 &normal, const idVec3 &point, const float epsilon ) const {
int i;
idVec3 dir, n, pointvec;
for ( i = 0; i < numPoints; i++ ) {
dir = p[(i+1) % numPoints].ToVec3() - p[i].ToVec3();
pointvec = point - p[i].ToVec3();
n = dir.Cross( normal );
if ( pointvec * n < -epsilon ) {
return false;
}
}
return true;
}
/*
=============
idWinding::LineIntersection
=============
*/
bool idWinding::LineIntersection( const idPlane &windingPlane, const idVec3 &start, const idVec3 &end, bool backFaceCull ) const {
float front, back, frac;
idVec3 mid;
front = windingPlane.Distance( start );
back = windingPlane.Distance( end );
// if both points at the same side of the plane
if ( front < 0.0f && back < 0.0f ) {
return false;
}
if ( front > 0.0f && back > 0.0f ) {
return false;
}
// if back face culled
if ( backFaceCull && front < 0.0f ) {
return false;
}
// get point of intersection with winding plane
if ( idMath::Fabs(front - back) < 0.0001f ) {
mid = end;
}
else {
frac = front / (front - back);
mid[0] = start[0] + (end[0] - start[0]) * frac;
mid[1] = start[1] + (end[1] - start[1]) * frac;
mid[2] = start[2] + (end[2] - start[2]) * frac;
}
return PointInside( windingPlane.Normal(), mid, 0.0f );
}
/*
=============
idWinding::RayIntersection
=============
*/
bool idWinding::RayIntersection( const idPlane &windingPlane, const idVec3 &start, const idVec3 &dir, float &scale, bool backFaceCull ) const {
int i;
bool side, lastside = false;
idPluecker pl1, pl2;
scale = 0.0f;
pl1.FromRay( start, dir );
for ( i = 0; i < numPoints; i++ ) {
pl2.FromLine( p[i].ToVec3(), p[(i+1)%numPoints].ToVec3() );
side = pl1.PermutedInnerProduct( pl2 ) > 0.0f;
if ( i && side != lastside ) {
return false;
}
lastside = side;
}
if ( !backFaceCull || lastside ) {
windingPlane.RayIntersection( start, dir, scale );
return true;
}
return false;
}
/*
=================
idWinding::TriangleArea
=================
*/
float idWinding::TriangleArea( const idVec3 &a, const idVec3 &b, const idVec3 &c ) {
idVec3 v1, v2;
idVec3 cross;
v1 = b - a;
v2 = c - a;
cross = v1.Cross( v2 );
return 0.5f * cross.Length();
}
//===============================================================
//
// idFixedWinding
//
//===============================================================
/*
=============
idFixedWinding::ReAllocate
=============
*/
bool idFixedWinding::ReAllocate( int n, bool keep ) {
assert( n <= MAX_POINTS_ON_WINDING );
if ( n > MAX_POINTS_ON_WINDING ) {
idLib::common->Printf("WARNING: idFixedWinding -> MAX_POINTS_ON_WINDING overflowed\n");
return false;
}
return true;
}
/*
=============
idFixedWinding::Split
=============
*/
int idFixedWinding::Split( idFixedWinding *back, const idPlane &plane, const float epsilon ) {
int counts[3];
float dists[MAX_POINTS_ON_WINDING+4];
byte sides[MAX_POINTS_ON_WINDING+4];
float dot;
int i, j;
idVec5 *p1, *p2;
idVec5 mid;
idFixedWinding out;
counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
// determine sides for each point
for ( i = 0; i < numPoints; i++ ) {
dists[i] = dot = plane.Distance( p[i].ToVec3() );
if ( dot > epsilon ) {
sides[i] = SIDE_FRONT;
} else if ( dot < -epsilon ) {
sides[i] = SIDE_BACK;
} else {
sides[i] = SIDE_ON;
}
counts[sides[i]]++;
}
if ( !counts[SIDE_BACK] ) {
if ( !counts[SIDE_FRONT] ) {
return SIDE_ON;
}
else {
return SIDE_FRONT;
}
}
if ( !counts[SIDE_FRONT] ) {
return SIDE_BACK;
}
sides[i] = sides[0];
dists[i] = dists[0];
out.numPoints = 0;
back->numPoints = 0;
for ( i = 0; i < numPoints; i++ ) {
p1 = &p[i];
if ( !out.EnsureAlloced( out.numPoints+1, true ) ) {
return SIDE_FRONT; // can't split -- fall back to original
}
if ( !back->EnsureAlloced( back->numPoints+1, true ) ) {
return SIDE_FRONT; // can't split -- fall back to original
}
if ( sides[i] == SIDE_ON ) {
out.p[out.numPoints] = *p1;
out.numPoints++;
back->p[back->numPoints] = *p1;
back->numPoints++;
continue;
}
if ( sides[i] == SIDE_FRONT ) {
out.p[out.numPoints] = *p1;
out.numPoints++;
}
if ( sides[i] == SIDE_BACK ) {
back->p[back->numPoints] = *p1;
back->numPoints++;
}
if ( sides[i+1] == SIDE_ON || sides[i+1] == sides[i] ) {
continue;
}
if ( !out.EnsureAlloced( out.numPoints+1, true ) ) {
return SIDE_FRONT; // can't split -- fall back to original
}
if ( !back->EnsureAlloced( back->numPoints+1, true ) ) {
return SIDE_FRONT; // can't split -- fall back to original
}
// generate a split point
j = i + 1;
if ( j >= numPoints ) {
p2 = &p[0];
}
else {
p2 = &p[j];
}
dot = dists[i] / (dists[i] - dists[i+1]);
for ( j = 0; j < 3; j++ ) {
// avoid round off error when possible
if ( plane.Normal()[j] == 1.0f ) {
mid[j] = plane.Dist();
} else if ( plane.Normal()[j] == -1.0f ) {
mid[j] = -plane.Dist();
} else {
mid[j] = (*p1)[j] + dot * ( (*p2)[j] - (*p1)[j] );
}
}
mid.s = p1->s + dot * ( p2->s - p1->s );
mid.t = p1->t + dot * ( p2->t - p1->t );
out.p[out.numPoints] = mid;
out.numPoints++;
back->p[back->numPoints] = mid;
back->numPoints++;
}
for ( i = 0; i < out.numPoints; i++ ) {
p[i] = out.p[i];
}
numPoints = out.numPoints;
return SIDE_CROSS;
}