dhewm3/neo/idlib/geometry/Surface.cpp
dhewg 736ec20d4d 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.
2011-12-19 23:21:47 +01:00

934 lines
29 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 "idlib/geometry/Surface.h"
/*
=================
UpdateVertexIndex
=================
*/
ID_INLINE int UpdateVertexIndex( int vertexIndexNum[2], int *vertexRemap, int *vertexCopyIndex, int vertNum ) {
int s = INTSIGNBITSET( vertexRemap[vertNum] );
vertexIndexNum[0] = vertexRemap[vertNum];
vertexRemap[vertNum] = vertexIndexNum[s];
vertexIndexNum[1] += s;
vertexCopyIndex[vertexRemap[vertNum]] = vertNum;
return vertexRemap[vertNum];
}
/*
=================
idSurface::Split
=================
*/
int idSurface::Split( const idPlane &plane, const float epsilon, idSurface **front, idSurface **back, int *frontOnPlaneEdges, int *backOnPlaneEdges ) const {
float * dists;
float f;
byte * sides;
int counts[3];
int * edgeSplitVertex;
int numEdgeSplitVertexes;
int * vertexRemap[2];
int vertexIndexNum[2][2];
int * vertexCopyIndex[2];
int * indexPtr[2];
int indexNum[2];
int * index;
int * onPlaneEdges[2];
int numOnPlaneEdges[2];
int maxOnPlaneEdges;
int i;
idSurface * surface[2];
idDrawVert v;
dists = (float *) _alloca( verts.Num() * sizeof( float ) );
sides = (byte *) _alloca( verts.Num() * sizeof( byte ) );
counts[0] = counts[1] = counts[2] = 0;
// determine side for each vertex
for ( i = 0; i < verts.Num(); i++ ) {
dists[i] = f = plane.Distance( verts[i].xyz );
if ( f > epsilon ) {
sides[i] = SIDE_FRONT;
} else if ( f < -epsilon ) {
sides[i] = SIDE_BACK;
} else {
sides[i] = SIDE_ON;
}
counts[sides[i]]++;
}
*front = *back = NULL;
// if coplanar, put on the front side if the normals match
if ( !counts[SIDE_FRONT] && !counts[SIDE_BACK] ) {
f = ( verts[indexes[1]].xyz - verts[indexes[0]].xyz ).Cross( verts[indexes[0]].xyz - verts[indexes[2]].xyz ) * plane.Normal();
if ( FLOATSIGNBITSET( f ) ) {
*back = new idSurface( *this );
return SIDE_BACK;
} else {
*front = new idSurface( *this );
return SIDE_FRONT;
}
}
// if nothing at the front of the clipping plane
if ( !counts[SIDE_FRONT] ) {
*back = new idSurface( *this );
return SIDE_BACK;
}
// if nothing at the back of the clipping plane
if ( !counts[SIDE_BACK] ) {
*front = new idSurface( *this );
return SIDE_FRONT;
}
// allocate front and back surface
*front = surface[0] = new idSurface();
*back = surface[1] = new idSurface();
edgeSplitVertex = (int *) _alloca( edges.Num() * sizeof( int ) );
numEdgeSplitVertexes = 0;
maxOnPlaneEdges = 4 * counts[SIDE_ON];
counts[SIDE_FRONT] = counts[SIDE_BACK] = counts[SIDE_ON] = 0;
// split edges
for ( i = 0; i < edges.Num(); i++ ) {
int v0 = edges[i].verts[0];
int v1 = edges[i].verts[1];
int sidesOr = ( sides[v0] | sides[v1] );
// if both vertexes are on the same side or one is on the clipping plane
if ( !( sides[v0] ^ sides[v1] ) || ( sidesOr & SIDE_ON ) ) {
edgeSplitVertex[i] = -1;
counts[sidesOr & SIDE_BACK]++;
counts[SIDE_ON] += ( sidesOr & SIDE_ON ) >> 1;
} else {
f = dists[v0] / ( dists[v0] - dists[v1] );
v.LerpAll( verts[v0], verts[v1], f );
edgeSplitVertex[i] = numEdgeSplitVertexes++;
surface[0]->verts.Append( v );
surface[1]->verts.Append( v );
}
}
// each edge is shared by at most two triangles, as such there can never be more indexes than twice the number of edges
surface[0]->indexes.Resize( ( ( counts[SIDE_FRONT] + counts[SIDE_ON] ) * 2 ) + ( numEdgeSplitVertexes * 4 ) );
surface[1]->indexes.Resize( ( ( counts[SIDE_BACK] + counts[SIDE_ON] ) * 2 ) + ( numEdgeSplitVertexes * 4 ) );
// allocate indexes to construct the triangle indexes for the front and back surface
vertexRemap[0] = (int *) _alloca( verts.Num() * sizeof( int ) );
memset( vertexRemap[0], -1, verts.Num() * sizeof( int ) );
vertexRemap[1] = (int *) _alloca( verts.Num() * sizeof( int ) );
memset( vertexRemap[1], -1, verts.Num() * sizeof( int ) );
vertexCopyIndex[0] = (int *) _alloca( ( numEdgeSplitVertexes + verts.Num() ) * sizeof( int ) );
vertexCopyIndex[1] = (int *) _alloca( ( numEdgeSplitVertexes + verts.Num() ) * sizeof( int ) );
vertexIndexNum[0][0] = vertexIndexNum[1][0] = 0;
vertexIndexNum[0][1] = vertexIndexNum[1][1] = numEdgeSplitVertexes;
indexPtr[0] = surface[0]->indexes.Ptr();
indexPtr[1] = surface[1]->indexes.Ptr();
indexNum[0] = surface[0]->indexes.Num();
indexNum[1] = surface[1]->indexes.Num();
maxOnPlaneEdges += 4 * numEdgeSplitVertexes;
// allocate one more in case no triangles are actually split which may happen for a disconnected surface
onPlaneEdges[0] = (int *) _alloca( ( maxOnPlaneEdges + 1 ) * sizeof( int ) );
onPlaneEdges[1] = (int *) _alloca( ( maxOnPlaneEdges + 1 ) * sizeof( int ) );
numOnPlaneEdges[0] = numOnPlaneEdges[1] = 0;
// split surface triangles
for ( i = 0; i < edgeIndexes.Num(); i += 3 ) {
int e0, e1, e2, v0, v1, v2, s, n;
e0 = abs( edgeIndexes[i+0] );
e1 = abs( edgeIndexes[i+1] );
e2 = abs( edgeIndexes[i+2] );
v0 = indexes[i+0];
v1 = indexes[i+1];
v2 = indexes[i+2];
switch( ( INTSIGNBITSET( edgeSplitVertex[e0] ) | ( INTSIGNBITSET( edgeSplitVertex[e1] ) << 1 ) | ( INTSIGNBITSET( edgeSplitVertex[e2] ) << 2 ) ) ^ 7 ) {
case 0: { // no edges split
if ( ( sides[v0] & sides[v1] & sides[v2] ) & SIDE_ON ) {
// coplanar
f = ( verts[v1].xyz - verts[v0].xyz ).Cross( verts[v0].xyz - verts[v2].xyz ) * plane.Normal();
s = FLOATSIGNBITSET( f );
} else {
s = ( sides[v0] | sides[v1] | sides[v2] ) & SIDE_BACK;
}
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]] = n;
numOnPlaneEdges[s] += ( sides[v0] & sides[v1] ) >> 1;
onPlaneEdges[s][numOnPlaneEdges[s]] = n+1;
numOnPlaneEdges[s] += ( sides[v1] & sides[v2] ) >> 1;
onPlaneEdges[s][numOnPlaneEdges[s]] = n+2;
numOnPlaneEdges[s] += ( sides[v2] & sides[v0] ) >> 1;
index = indexPtr[s];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
indexNum[s] = n;
break;
}
case 1: { // first edge split
s = sides[v0] & SIDE_BACK;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e0];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
indexNum[s] = n;
s ^= 1;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
index[n++] = edgeSplitVertex[e0];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
indexNum[s] = n;
break;
}
case 2: { // second edge split
s = sides[v1] & SIDE_BACK;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e1];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
indexNum[s] = n;
s ^= 1;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
index[n++] = edgeSplitVertex[e1];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
indexNum[s] = n;
break;
}
case 3: { // first and second edge split
s = sides[v1] & SIDE_BACK;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e1];
index[n++] = edgeSplitVertex[e0];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
indexNum[s] = n;
s ^= 1;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e0];
index[n++] = edgeSplitVertex[e1];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
index[n++] = edgeSplitVertex[e1];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
indexNum[s] = n;
break;
}
case 4: { // third edge split
s = sides[v2] & SIDE_BACK;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e2];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
indexNum[s] = n;
s ^= 1;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
index[n++] = edgeSplitVertex[e2];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
indexNum[s] = n;
break;
}
case 5: { // first and third edge split
s = sides[v0] & SIDE_BACK;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e0];
index[n++] = edgeSplitVertex[e2];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
indexNum[s] = n;
s ^= 1;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e2];
index[n++] = edgeSplitVertex[e0];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
index[n++] = edgeSplitVertex[e2];
indexNum[s] = n;
break;
}
case 6: { // second and third edge split
s = sides[v2] & SIDE_BACK;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e2];
index[n++] = edgeSplitVertex[e1];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v2 );
indexNum[s] = n;
s ^= 1;
n = indexNum[s];
onPlaneEdges[s][numOnPlaneEdges[s]++] = n;
index = indexPtr[s];
index[n++] = edgeSplitVertex[e1];
index[n++] = edgeSplitVertex[e2];
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v0 );
index[n++] = UpdateVertexIndex( vertexIndexNum[s], vertexRemap[s], vertexCopyIndex[s], v1 );
index[n++] = edgeSplitVertex[e2];
indexNum[s] = n;
break;
}
}
}
surface[0]->indexes.SetNum( indexNum[0], false );
surface[1]->indexes.SetNum( indexNum[1], false );
// copy vertexes
surface[0]->verts.SetNum( vertexIndexNum[0][1], false );
index = vertexCopyIndex[0];
for ( i = numEdgeSplitVertexes; i < surface[0]->verts.Num(); i++ ) {
surface[0]->verts[i] = verts[index[i]];
}
surface[1]->verts.SetNum( vertexIndexNum[1][1], false );
index = vertexCopyIndex[1];
for ( i = numEdgeSplitVertexes; i < surface[1]->verts.Num(); i++ ) {
surface[1]->verts[i] = verts[index[i]];
}
// generate edge indexes
surface[0]->GenerateEdgeIndexes();
surface[1]->GenerateEdgeIndexes();
if ( frontOnPlaneEdges ) {
memcpy( frontOnPlaneEdges, onPlaneEdges[0], numOnPlaneEdges[0] * sizeof( int ) );
frontOnPlaneEdges[numOnPlaneEdges[0]] = -1;
}
if ( backOnPlaneEdges ) {
memcpy( backOnPlaneEdges, onPlaneEdges[1], numOnPlaneEdges[1] * sizeof( int ) );
backOnPlaneEdges[numOnPlaneEdges[1]] = -1;
}
return SIDE_CROSS;
}
/*
=================
idSurface::ClipInPlace
=================
*/
bool idSurface::ClipInPlace( const idPlane &plane, const float epsilon, const bool keepOn ) {
float * dists;
float f;
byte * sides;
int counts[3];
int i;
int * edgeSplitVertex;
int * vertexRemap;
int vertexIndexNum[2];
int * vertexCopyIndex;
int * indexPtr;
int indexNum;
int numEdgeSplitVertexes;
idDrawVert v;
idList<idDrawVert> newVerts;
idList<int> newIndexes;
dists = (float *) _alloca( verts.Num() * sizeof( float ) );
sides = (byte *) _alloca( verts.Num() * sizeof( byte ) );
counts[0] = counts[1] = counts[2] = 0;
// determine side for each vertex
for ( i = 0; i < verts.Num(); i++ ) {
dists[i] = f = plane.Distance( verts[i].xyz );
if ( f > epsilon ) {
sides[i] = SIDE_FRONT;
} else if ( f < -epsilon ) {
sides[i] = SIDE_BACK;
} else {
sides[i] = SIDE_ON;
}
counts[sides[i]]++;
}
// if coplanar, put on the front side if the normals match
if ( !counts[SIDE_FRONT] && !counts[SIDE_BACK] ) {
f = ( verts[indexes[1]].xyz - verts[indexes[0]].xyz ).Cross( verts[indexes[0]].xyz - verts[indexes[2]].xyz ) * plane.Normal();
if ( FLOATSIGNBITSET( f ) ) {
Clear();
return false;
} else {
return true;
}
}
// if nothing at the front of the clipping plane
if ( !counts[SIDE_FRONT] ) {
Clear();
return false;
}
// if nothing at the back of the clipping plane
if ( !counts[SIDE_BACK] ) {
return true;
}
edgeSplitVertex = (int *) _alloca( edges.Num() * sizeof( int ) );
numEdgeSplitVertexes = 0;
counts[SIDE_FRONT] = counts[SIDE_BACK] = 0;
// split edges
for ( i = 0; i < edges.Num(); i++ ) {
int v0 = edges[i].verts[0];
int v1 = edges[i].verts[1];
// if both vertexes are on the same side or one is on the clipping plane
if ( !( sides[v0] ^ sides[v1] ) || ( ( sides[v0] | sides[v1] ) & SIDE_ON ) ) {
edgeSplitVertex[i] = -1;
counts[(sides[v0]|sides[v1]) & SIDE_BACK]++;
} else {
f = dists[v0] / ( dists[v0] - dists[v1] );
v.LerpAll( verts[v0], verts[v1], f );
edgeSplitVertex[i] = numEdgeSplitVertexes++;
newVerts.Append( v );
}
}
// each edge is shared by at most two triangles, as such there can never be
// more indexes than twice the number of edges
newIndexes.Resize( ( counts[SIDE_FRONT] << 1 ) + ( numEdgeSplitVertexes << 2 ) );
// allocate indexes to construct the triangle indexes for the front and back surface
vertexRemap = (int *) _alloca( verts.Num() * sizeof( int ) );
memset( vertexRemap, -1, verts.Num() * sizeof( int ) );
vertexCopyIndex = (int *) _alloca( ( numEdgeSplitVertexes + verts.Num() ) * sizeof( int ) );
vertexIndexNum[0] = 0;
vertexIndexNum[1] = numEdgeSplitVertexes;
indexPtr = newIndexes.Ptr();
indexNum = newIndexes.Num();
// split surface triangles
for ( i = 0; i < edgeIndexes.Num(); i += 3 ) {
int e0, e1, e2, v0, v1, v2;
e0 = abs( edgeIndexes[i+0] );
e1 = abs( edgeIndexes[i+1] );
e2 = abs( edgeIndexes[i+2] );
v0 = indexes[i+0];
v1 = indexes[i+1];
v2 = indexes[i+2];
switch( ( INTSIGNBITSET( edgeSplitVertex[e0] ) | ( INTSIGNBITSET( edgeSplitVertex[e1] ) << 1 ) | ( INTSIGNBITSET( edgeSplitVertex[e2] ) << 2 ) ) ^ 7 ) {
case 0: { // no edges split
if ( ( sides[v0] | sides[v1] | sides[v2] ) & SIDE_BACK ) {
break;
}
if ( ( sides[v0] & sides[v1] & sides[v2] ) & SIDE_ON ) {
// coplanar
if ( !keepOn ) {
break;
}
f = ( verts[v1].xyz - verts[v0].xyz ).Cross( verts[v0].xyz - verts[v2].xyz ) * plane.Normal();
if ( FLOATSIGNBITSET( f ) ) {
break;
}
}
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
break;
}
case 1: { // first edge split
if ( !( sides[v0] & SIDE_BACK ) ) {
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
indexPtr[indexNum++] = edgeSplitVertex[e0];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
} else {
indexPtr[indexNum++] = edgeSplitVertex[e0];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
}
break;
}
case 2: { // second edge split
if ( !( sides[v1] & SIDE_BACK ) ) {
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = edgeSplitVertex[e1];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
} else {
indexPtr[indexNum++] = edgeSplitVertex[e1];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
}
break;
}
case 3: { // first and second edge split
if ( !( sides[v1] & SIDE_BACK ) ) {
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = edgeSplitVertex[e1];
indexPtr[indexNum++] = edgeSplitVertex[e0];
} else {
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
indexPtr[indexNum++] = edgeSplitVertex[e0];
indexPtr[indexNum++] = edgeSplitVertex[e1];
indexPtr[indexNum++] = edgeSplitVertex[e1];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
}
break;
}
case 4: { // third edge split
if ( !( sides[v2] & SIDE_BACK ) ) {
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
indexPtr[indexNum++] = edgeSplitVertex[e2];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
} else {
indexPtr[indexNum++] = edgeSplitVertex[e2];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
}
break;
}
case 5: { // first and third edge split
if ( !( sides[v0] & SIDE_BACK ) ) {
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
indexPtr[indexNum++] = edgeSplitVertex[e0];
indexPtr[indexNum++] = edgeSplitVertex[e2];
} else {
indexPtr[indexNum++] = edgeSplitVertex[e0];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = edgeSplitVertex[e2];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
indexPtr[indexNum++] = edgeSplitVertex[e2];
}
break;
}
case 6: { // second and third edge split
if ( !( sides[v2] & SIDE_BACK ) ) {
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v2 );
indexPtr[indexNum++] = edgeSplitVertex[e2];
indexPtr[indexNum++] = edgeSplitVertex[e1];
} else {
indexPtr[indexNum++] = edgeSplitVertex[e2];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = edgeSplitVertex[e1];
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v0 );
indexPtr[indexNum++] = UpdateVertexIndex( vertexIndexNum, vertexRemap, vertexCopyIndex, v1 );
indexPtr[indexNum++] = edgeSplitVertex[e2];
}
break;
}
}
}
newIndexes.SetNum( indexNum, false );
// copy vertexes
newVerts.SetNum( vertexIndexNum[1], false );
for ( i = numEdgeSplitVertexes; i < newVerts.Num(); i++ ) {
newVerts[i] = verts[vertexCopyIndex[i]];
}
// copy back to this surface
indexes = newIndexes;
verts = newVerts;
GenerateEdgeIndexes();
return true;
}
/*
=============
idSurface::IsConnected
=============
*/
bool idSurface::IsConnected( void ) const {
int i, j, numIslands, numTris;
int queueStart, queueEnd;
int *queue, *islandNum;
int curTri, nextTri, edgeNum;
const int *index;
numIslands = 0;
numTris = indexes.Num() / 3;
islandNum = (int *) _alloca16( numTris * sizeof( int ) );
memset( islandNum, -1, numTris * sizeof( int ) );
queue = (int *) _alloca16( numTris * sizeof( int ) );
for ( i = 0; i < numTris; i++ ) {
if ( islandNum[i] != -1 ) {
continue;
}
queueStart = 0;
queueEnd = 1;
queue[0] = i;
islandNum[i] = numIslands;
for ( curTri = queue[queueStart]; queueStart < queueEnd; curTri = queue[++queueStart] ) {
index = &edgeIndexes[curTri * 3];
for ( j = 0; j < 3; j++ ) {
edgeNum = index[j];
nextTri = edges[abs(edgeNum)].tris[INTSIGNBITNOTSET(edgeNum)];
if ( nextTri == -1 ) {
continue;
}
nextTri /= 3;
if ( islandNum[nextTri] != -1 ) {
continue;
}
queue[queueEnd++] = nextTri;
islandNum[nextTri] = numIslands;
}
}
numIslands++;
}
return ( numIslands == 1 );
}
/*
=================
idSurface::IsClosed
=================
*/
bool idSurface::IsClosed( void ) const {
for ( int i = 0; i < edges.Num(); i++ ) {
if ( edges[i].tris[0] < 0 || edges[i].tris[1] < 0 ) {
return false;
}
}
return true;
}
/*
=============
idSurface::IsPolytope
=============
*/
bool idSurface::IsPolytope( const float epsilon ) const {
int i, j;
idPlane plane;
if ( !IsClosed() ) {
return false;
}
for ( i = 0; i < indexes.Num(); i += 3 ) {
if (!plane.FromPoints( verts[indexes[i+0]].xyz, verts[indexes[i+1]].xyz, verts[indexes[i+2]].xyz ))
return false;
for ( j = 0; j < verts.Num(); j++ ) {
if ( plane.Side( verts[j].xyz, epsilon ) == SIDE_FRONT ) {
return false;
}
}
}
return true;
}
/*
=============
idSurface::PlaneDistance
=============
*/
float idSurface::PlaneDistance( const idPlane &plane ) const {
int i;
float d, min, max;
min = idMath::INFINITY;
max = -min;
for ( i = 0; i < verts.Num(); i++ ) {
d = plane.Distance( verts[i].xyz );
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;
}
/*
=============
idSurface::PlaneSide
=============
*/
int idSurface::PlaneSide( const idPlane &plane, const float epsilon ) const {
bool front, back;
int i;
float d;
front = false;
back = false;
for ( i = 0; i < verts.Num(); i++ ) {
d = plane.Distance( verts[i].xyz );
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;
}
/*
=================
idSurface::LineIntersection
=================
*/
bool idSurface::LineIntersection( const idVec3 &start, const idVec3 &end, bool backFaceCull ) const {
float scale;
RayIntersection( start, end - start, scale, false );
return ( scale >= 0.0f && scale <= 1.0f );
}
/*
=================
idSurface::RayIntersection
=================
*/
bool idSurface::RayIntersection( const idVec3 &start, const idVec3 &dir, float &scale, bool backFaceCull ) const {
int i, i0, i1, i2, s0, s1, s2;
float d, s = 0.0f;
byte *sidedness;
idPluecker rayPl, pl;
idPlane plane;
sidedness = (byte *)_alloca( edges.Num() * sizeof(byte) );
scale = idMath::INFINITY;
rayPl.FromRay( start, dir );
// ray sidedness for edges
for ( i = 0; i < edges.Num(); i++ ) {
pl.FromLine( verts[ edges[i].verts[1] ].xyz, verts[ edges[i].verts[0] ].xyz );
d = pl.PermutedInnerProduct( rayPl );
sidedness[ i ] = FLOATSIGNBITSET( d );
}
// test triangles
for ( i = 0; i < edgeIndexes.Num(); i += 3 ) {
i0 = edgeIndexes[i+0];
i1 = edgeIndexes[i+1];
i2 = edgeIndexes[i+2];
s0 = sidedness[abs(i0)] ^ INTSIGNBITSET( i0 );
s1 = sidedness[abs(i1)] ^ INTSIGNBITSET( i1 );
s2 = sidedness[abs(i2)] ^ INTSIGNBITSET( i2 );
if ( s0 & s1 & s2 ) {
if (!plane.FromPoints( verts[indexes[i+0]].xyz, verts[indexes[i+1]].xyz, verts[indexes[i+2]].xyz ))
return false;
plane.RayIntersection( start, dir, s );
if ( idMath::Fabs( s ) < idMath::Fabs( scale ) ) {
scale = s;
}
} else if ( !backFaceCull && !(s0 | s1 | s2) ) {
if (!plane.FromPoints( verts[indexes[i+0]].xyz, verts[indexes[i+1]].xyz, verts[indexes[i+2]].xyz ))
return false;
plane.RayIntersection( start, dir, s );
if ( idMath::Fabs( s ) < idMath::Fabs( scale ) ) {
scale = s;
}
}
}
if ( idMath::Fabs( scale ) < idMath::INFINITY ) {
return true;
}
return false;
}
/*
=================
idSurface::GenerateEdgeIndexes
Assumes each edge is shared by at most two triangles.
=================
*/
void idSurface::GenerateEdgeIndexes( void ) {
int i, j, i0, i1, i2, s, v0, v1, edgeNum;
int *index, *vertexEdges, *edgeChain;
surfaceEdge_t e[3];
vertexEdges = (int *) _alloca16( verts.Num() * sizeof( int ) );
memset( vertexEdges, -1, verts.Num() * sizeof( int ) );
edgeChain = (int *) _alloca16( indexes.Num() * sizeof( int ) );
edgeIndexes.SetNum( indexes.Num(), true );
edges.Clear();
// the first edge is a dummy
e[0].verts[0] = e[0].verts[1] = e[0].tris[0] = e[0].tris[1] = 0;
edges.Append( e[0] );
for ( i = 0; i < indexes.Num(); i += 3 ) {
index = indexes.Ptr() + i;
// vertex numbers
i0 = index[0];
i1 = index[1];
i2 = index[2];
// setup edges each with smallest vertex number first
s = INTSIGNBITSET(i1 - i0);
e[0].verts[0] = index[s];
e[0].verts[1] = index[s^1];
s = INTSIGNBITSET(i2 - i1) + 1;
e[1].verts[0] = index[s];
e[1].verts[1] = index[s^3];
s = INTSIGNBITSET(i2 - i0) << 1;
e[2].verts[0] = index[s];
e[2].verts[1] = index[s^2];
// get edges
for ( j = 0; j < 3; j++ ) {
v0 = e[j].verts[0];
v1 = e[j].verts[1];
for ( edgeNum = vertexEdges[v0]; edgeNum >= 0; edgeNum = edgeChain[edgeNum] ) {
if ( edges[edgeNum].verts[1] == v1 ) {
break;
}
}
// if the edge does not yet exist
if ( edgeNum < 0 ) {
e[j].tris[0] = e[j].tris[1] = -1;
edgeNum = edges.Append( e[j] );
edgeChain[edgeNum] = vertexEdges[v0];
vertexEdges[v0] = edgeNum;
}
// update edge index and edge tri references
if ( index[j] == v0 ) {
assert( edges[edgeNum].tris[0] == -1 ); // edge may not be shared by more than two triangles
edges[edgeNum].tris[0] = i;
edgeIndexes[i+j] = edgeNum;
} else {
assert( edges[edgeNum].tris[1] == -1 ); // edge may not be shared by more than two triangles
edges[edgeNum].tris[1] = i;
edgeIndexes[i+j] = -edgeNum;
}
}
}
}
/*
=================
idSurface::FindEdge
=================
*/
int idSurface::FindEdge( int v1, int v2 ) const {
int i, firstVert, secondVert;
if ( v1 < v2 ) {
firstVert = v1;
secondVert = v2;
} else {
firstVert = v2;
secondVert = v1;
}
for ( i = 1; i < edges.Num(); i++ ) {
if ( edges[i].verts[0] == firstVert ) {
if ( edges[i].verts[1] == secondVert ) {
break;
}
}
}
if ( i < edges.Num() ) {
return v1 < v2 ? i : -i;
}
return 0;
}