d4708
/
source-engine
mirror of https://github.com/nillerusr/source-engine.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
Modified source engine (2017) developed by valve and leaked in 2020. Not for commercial purporses
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
551 Commits
25 Branches
6 Tags
221 MiB
 
 
 
 
 
 
Branch: master
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'master'
${ noResults }
source-engine/vphysics/trace.cpp

2474 lines
71 KiB
Raw Permalink Blame History

//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose:
//
// $NoKeywords: $
//
//=============================================================================//
#include "cbase.h"
#include "cmodel.h"
#include "physics_trace.h"
#include "ivp_surman_polygon.hxx"
#include "ivp_compact_ledge.hxx"
#include "ivp_compact_ledge_solver.hxx"
#include "ivp_compact_surface.hxx"
#include "tier0/vprof.h"
#include "mathlib/ssemath.h"
#include "tier0/tslist.h"
// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"
// this skips the sphere tree stuff for tracing
#define DEBUG_TEST_ALL_LEDGES 0
// this skips the optimization that shrinks the ray as each intersection is encountered
#define DEBUG_KEEP_FULL_RAY 0
// this skips the optimization that looks up the first vert in a cubemap
#define USE_COLLIDE_MAP 1
// objects with small numbers of verts build a cache of pre-transformed verts
#define USE_VERT_CACHE 1
#define USE_RLE_SPANS 1
// UNDONE: This is a boost on PC, but doesn't work yet on x360 - investigate
#define SIMD_MATRIX 0
// turn this on to get asserts in the low-level collision solver
#define CHECK_TOI_CALCS 0
#define BRUTE_FORCE_VERT_COUNT 128
// NOTE: This is in inches (HL units)
#define TEST_EPSILON (g_PhysicsUnits.collisionSweepIncrementalEpsilon)
struct simplexvert_t
{
Vector position;
unsigned short testIndex : 15;
unsigned short sweepIndex : 1;
unsigned short obstacleIndex;
};
struct simplex_t
{
simplexvert_t verts[4];
int vertCount;
inline bool PointSimplex( const simplexvert_t &newPoint, Vector *pOut );
inline bool EdgeSimplex( const simplexvert_t &newPoint, int outIndex, const Vector &edge, Vector *pOut );
inline bool TriangleSimplex( const simplexvert_t &newPoint, int outIndex, const Vector &faceNormal, Vector *pOut );
bool SolveGJKSet( const simplexvert_t &newPoint, Vector *pOut );
bool SolveVoronoiRegion2( const simplexvert_t &newPoint, Vector *pOut );
bool SolveVoronoiRegion3( const simplexvert_t &newPoint, Vector *pOut );
bool SolveVoronoiRegion4( const simplexvert_t &newPoint, Vector *pOut );
Vector ClipRayToTetrahedronBase( const Vector &dir );
Vector ClipRayToTetrahedron( const Vector &dir );
float ClipRayToTriangle( const Vector &dir, float epsilon );
};
class CTraceCone : public ITraceObject
{
public:
CTraceCone( const truncatedcone_t &cone, const Vector &translation )
{
m_cone = cone;
m_cone.origin += translation;
float cosTheta;
SinCos( DEG2RAD(m_cone.theta), &m_sinTheta, &cosTheta );
m_radius = m_cone.h * m_sinTheta / cosTheta;
m_centerBase = m_cone.origin + m_cone.h * m_cone.normal;
}
virtual int SupportMap( const Vector &dir, Vector *pOut ) const
{
Vector unitDir = dir;
VectorNormalize(unitDir);
float dot = DotProduct( unitDir, m_cone.normal );
// anti-cone is -normal, angle = 90 - theta
// If the normal is in the anti-cone, then return the apex
// not in anti-cone, support map is on the surface of the disc
if ( dot > -m_sinTheta )
{
unitDir -= m_cone.normal * dot;
float len = VectorNormalize( unitDir );
if ( len > 1e-4f )
{
*pOut = m_centerBase + (unitDir * m_radius);
return 0;
}
*pOut = m_centerBase;
return 0;
}
// outside the cone's angle, support map is on the surface of the cone
*pOut = m_cone.origin;
return 0;
}
// BUGBUG: Doesn't work!
virtual Vector GetVertByIndex( int index ) const { return m_cone.origin; }
virtual float Radius( void ) const { return m_cone.h + m_radius; }
truncatedcone_t m_cone;
float m_radius;
float m_sinTheta;
Vector m_centerBase;
};
// really this is indexing a vertex, but the iteration code needs a triangle + edge index.
// edge is always 0-2 so return it in the bottom 2 bits
static unsigned short GetPackedIndex( const IVP_Compact_Ledge *pLedge, const IVP_U_Float_Point &dir )
{
const IVP_Compact_Poly_Point *RESTRICT pPoints = pLedge->get_point_array();
const IVP_Compact_Triangle *RESTRICT pTri = pLedge->get_first_triangle();
const IVP_Compact_Edge *RESTRICT pEdge = pTri->get_edge( 0 );
int best = pEdge->get_start_point_index();
float bestDot = pPoints[best].dot_product( &dir );
int triCount = pLedge->get_n_triangles();
const IVP_Compact_Triangle *RESTRICT pBestTri = pTri;
// this loop will early out, but keep it from being infinite
int i;
// hillclimbing search to find the best support vert
for ( i = 0; i < triCount; i++ )
{
// get the index to the end vert of this edge (start vert on next edge)
pEdge = pEdge->get_prev();
int stopVert = pEdge->get_start_point_index();
// loop through the verts that can be reached along edges from this vert
// stop if you get back to the one you're starting on.
int vert = stopVert;
do
{
float dot = pPoints[vert].dot_product( &dir );
if ( dot > bestDot )
{
bestDot = dot;
best = vert;
pBestTri = pEdge->get_triangle();
break;
}
// tri opposite next edge, same starting vert as next edge
pEdge = pEdge->get_opposite()->get_prev();
vert = pEdge->get_start_point_index();
} while ( vert != stopVert );
// if you exhausted the possibilities for this vert, it must be the best vert
if ( vert != best )
break;
}
int triIndex = pBestTri - pLedge->get_first_triangle();
int edgeIndex = 0;
// just do a search for the edge containing this vert instead of storing it along the way
for ( i = 0; i < 3; i++ )
{
if ( pBestTri->get_edge(i)->get_start_point_index() == best )
{
edgeIndex = i;
break;
}
}
return (unsigned short) ( (triIndex<<2) + edgeIndex );
}
void InitLeafmap( IVP_Compact_Ledge *pLedge, leafmap_t *pLeafmapOut )
{
pLeafmapOut->pLeaf = pLedge;
pLeafmapOut->vertCount = 0;
pLeafmapOut->flags = 0;
pLeafmapOut->spanCount = 0;
if ( pLedge && pLedge->is_terminal() )
{
// for small numbers of verts it's much faster to simply do dot products with all verts
// since the best case for hillclimbing is to touch the start vert plus all neighbors (avg_valence+1 dots)
// in t
int triCount = pLedge->get_n_triangles();
// this is a guess that anything with more than brute_force * 4 tris will have at least brute_force verts
if ( triCount <= BRUTE_FORCE_VERT_COUNT*4 )
{
Assert(triCount>0);
int minV = MAX_CONVEX_VERTS;
int maxV = 0;
for ( int i = 0; i < triCount; i++ )
{
const IVP_Compact_Triangle *pTri = pLedge->get_first_triangle() + i;
for ( int j = 0; j < 3; j++ )
{
const IVP_Compact_Edge *pEdge = pTri->get_edge( j );
int v = pEdge->get_start_point_index();
if ( v < minV )
{
minV = v;
}
if ( v > maxV )
{
maxV = v;
}
}
}
int vertCount = (maxV-minV) + 1;
// max possible verts is < 48, so this is just here for some real failure
// or vert sharing with a large collection of convexes. In that case the
// number could be high, but this approach to implementing support is invalid
// because the vert range is polluted
if ( vertCount < BRUTE_FORCE_VERT_COUNT )
{
char hasVert[BRUTE_FORCE_VERT_COUNT];
memset(hasVert, 0, sizeof(hasVert[0])*vertCount);
for ( int i = 0; i < triCount; i++ )
{
const IVP_Compact_Triangle *pTri = pLedge->get_first_triangle() + i;
for ( int j = 0; j < 3; j++ )
{
// mark each vert in the list
const IVP_Compact_Edge *pEdge = pTri->get_edge( j );
int v = pEdge->get_start_point_index();
hasVert[v-minV] = true;
}
}
// now find the vertex spans and encode them
byte spans[BRUTE_FORCE_VERT_COUNT];
int spanIndex = 0;
char has = hasVert[0];
Assert(has);
byte count = 1;
for ( int i = 1; i < vertCount && spanIndex < BRUTE_FORCE_VERT_COUNT; i++ )
{
// each change of state is a new span
if ( has != hasVert[i] )
{
spans[spanIndex] = count;
has = hasVert[i];
count = 0;
spanIndex++;
}
count++;
Assert(count < 255);
}
// rle spans only supported with vertex caching
#if USE_VERT_CACHE && USE_RLE_SPANS
if ( spanIndex < BRUTE_FORCE_VERT_COUNT )
#else
if ( spanIndex < 1 )
#endif
{
spans[spanIndex] = count;
spanIndex++;
pLeafmapOut->SetRLESpans( minV, spanIndex, spans );
}
}
}
}
if ( !pLeafmapOut->HasSpans() )
{
// otherwise make a 8-way directional map to pick the best start vert for hillclimbing
pLeafmapOut->SetHasCubemap();
for ( int i = 0; i < 8; i++ )
{
IVP_U_Float_Point tmp;
tmp.k[0] = ( i & 1 ) ? -1 : 1;
tmp.k[1] = ( i & 2 ) ? -1 : 1;
tmp.k[2] = ( i & 4 ) ? -1 : 1;
pLeafmapOut->startVert[i] = GetPackedIndex( pLedge, tmp );
}
}
}
void GetStartVert( const leafmap_t *pLeafmap, const IVP_U_Float_Point &localDirection, int &triIndex, int &edgeIndex )
{
if ( !pLeafmap || !pLeafmap->HasCubemap() )
return;
// map dir to index
int cacheIndex = (localDirection.k[0] < 0 ? 1 : 0) + (localDirection.k[1] < 0 ? 2 : 0) + (localDirection.k[2] < 0 ? 4 : 0 );
triIndex = pLeafmap->startVert[cacheIndex] >> 2;
edgeIndex = pLeafmap->startVert[cacheIndex] & 0x3;
}
CTSPool<CVisitHash> g_VisitHashPool;
CVisitHash *AllocVisitHash()
{
return g_VisitHashPool.GetObject();
}
void FreeVisitHash(CVisitHash *pFree)
{
if ( pFree )
{
g_VisitHashPool.PutObject(pFree);
}
}
//-----------------------------------------------------------------------------
// Purpose: Implementation for Trace against an IVP object
//-----------------------------------------------------------------------------
class CTraceIVP : public ITraceObject
{
public:
CTraceIVP( const CPhysCollide *pCollide, const Vector &origin, const QAngle &angles );
~CTraceIVP()
{
if ( m_pVisitHash )
FreeVisitHash(m_pVisitHash);
}
virtual int SupportMap( const Vector &dir, Vector *pOut ) const;
virtual Vector GetVertByIndex( int index ) const;
// UNDONE: Do general ITraceObject center/offset computation and move the ray to account
// for this delta like we do in TraceSweepIVP()
// Then we can shrink the radius of objects with mass centers NOT at the origin
virtual float Radius( void ) const
{
return m_radius;
}
inline float TransformLengthToLocal( float length )
{
return ConvertDistanceToIVP( length );
}
// UNDONE: Optimize this by storing 3 matrices? (one for each transform that includes rot/scale for HL/IVP)?
// UNDONE: Not necessary if we remove the coordinate conversion
inline void TransformDirectionToLocal( const Vector &dir, IVP_U_Float_Point &local ) const
{
IVP_U_Float_Point tmp;
ConvertDirectionToIVP( dir, tmp );
m_matrix.vimult3( &tmp, &local );
}
inline void RotateRelativePositionToLocal( const Vector &delta, IVP_U_Float_Point &local ) const
{
IVP_U_Float_Point tmp;
ConvertPositionToIVP( delta, tmp );
m_matrix.vimult3( &tmp, &local );
}
inline void TransformPositionToLocal( const Vector &pos, IVP_U_Float_Point &local ) const
{
IVP_U_Float_Point tmp;
ConvertPositionToIVP( pos, tmp );
m_matrix.vimult4( &tmp, &local );
}
inline void TransformPositionFromLocal( const IVP_U_Float_Point &local, Vector &out ) const
{
VectorTransform( *(Vector *)&local, *((const matrix3x4_t *)&m_ivpLocalToHLWorld), out );
}
#if USE_VERT_CACHE
inline Vector CachedVertByIndex(int index) const
{
int subIndex = index & 3;
return m_vertCache[index>>2].Vec(subIndex);
}
#endif
bool IsValid( void ) { return m_pLedge != NULL; }
void AllocateVisitHash()
{
if ( !m_pVisitHash )
m_pVisitHash = AllocVisitHash();
}
void SetLedge( const IVP_Compact_Ledge *pLedge )
{
m_pLedge = pLedge;
m_pLeafmap = NULL;
if ( !pLedge )
return;
#if USE_VERT_CACHE
m_cacheCount = 0;
#endif
if ( m_pCollideMap )
{
for ( int i = 0; i < m_pCollideMap->leafCount; i++ )
{
if ( m_pCollideMap->leafmap[i].pLeaf == pLedge )
{
m_pLeafmap = &m_pCollideMap->leafmap[i];
if ( !BuildLeafmapCache( &m_pCollideMap->leafmap[i] ) )
{
AllocateVisitHash();
}
return;
}
}
}
AllocateVisitHash();
}
bool SetSingleConvex( void )
{
const IVP_Compact_Ledgetree_Node *node = m_pSurface->get_compact_ledge_tree_root();
if ( node->is_terminal() == IVP_TRUE )
{
SetLedge( node->get_compact_ledge() );
return true;
}
SetLedge( NULL );
return false;
}
bool BuildLeafmapCache(const leafmap_t * RESTRICT pLeafmap);
bool BuildLeafmapCacheRLE( const leafmap_t * RESTRICT pLeafmap );
inline int SupportMapCached( const Vector &dir, Vector *pOut ) const;
const collidemap_t *m_pCollideMap;
const IVP_Compact_Surface *m_pSurface;
private:
const leafmap_t *m_pLeafmap;
const IVP_Compact_Ledge *m_pLedge;
CVisitHash *m_pVisitHash;
#if SIMD_MATRIX
FourVectors m_ivpLocalToHLWorld;
#else
matrix3x4_t m_ivpLocalToHLWorld;
#endif
IVP_U_Matrix m_matrix;
// transform that includes scale from IVP to HL coords, do not VectorITransform or VectorRotate with this
float m_radius;
int m_nPointTest;
int m_nStartPoint;
bool m_bHasTranslation;
#if USE_VERT_CACHE
int m_cacheCount; // number of FourVectors used
FourVectors m_vertCache[BRUTE_FORCE_VERT_COUNT/4];
#endif
};
// GCC 4.2.1 can't handle loading a static const into a m128 register :(
#ifdef WIN32
static const
#endif
fltx4 g_IVPToHLDir = { 1.0f, -1.0f, 1.0f, 1.0f };
//static const fltx4 g_IVPToHLPosition = { IVP2HL(1.0f), -IVP2HL(1.0f), IVP2HL(1.0f), IVP2HL(1.0f) };
#if defined(_X360)
FORCEINLINE fltx4 ConvertDirectionToIVP( const fltx4 & a )
{
fltx4 t = __vpermwi( a, VPERMWI_CONST( 0, 2, 1, 3 ) );
// negate Y
return MulSIMD( t, g_IVPToHLDir );
}
#else
FORCEINLINE fltx4 ConvertDirectionToIVP( const fltx4 & a )
{
// swap Z & Y
fltx4 t = _mm_shuffle_ps( a, a, MM_SHUFFLE_REV( 0, 2, 1, 3 ) );
// negate Y
return MulSIMD( t, g_IVPToHLDir );
}
#endif
CTraceIVP::CTraceIVP( const CPhysCollide *pCollide, const Vector &origin, const QAngle &angles )
{
#if USE_COLLIDE_MAP
m_pCollideMap = pCollide->GetCollideMap();
#else
m_pCollideMap = NULL;
#endif
m_pSurface = pCollide->GetCompactSurface();
m_pLedge = NULL;
m_pVisitHash = NULL;
m_bHasTranslation = (origin==vec3_origin) ? false : true;
// UNDONE: Move this offset calculation into the tracing routines
// I didn't do this now because it seems to require changes to most of the
// transform routines - and this would cause bugs.
float centerOffset = VectorLength( m_pSurface->mass_center.k );
#if SIMD_MATRIX
VectorAligned forward, right, up;
IVP_U_Float_Point ivpForward, ivpLeft, ivpUp;
AngleVectors( angles, &forward, &right, &up );
Vector left = -right;
Vector down = -up;
ConvertDirectionToIVP( forward, ivpForward );
ConvertDirectionToIVP( left, ivpLeft );
ConvertDirectionToIVP( down, ivpUp );
m_matrix.set_col( IVP_INDEX_X, &ivpForward );
m_matrix.set_col( IVP_INDEX_Z, &ivpLeft );
m_matrix.set_col( IVP_INDEX_Y, &ivpUp );
ConvertPositionToIVP( origin, m_matrix.vv );
forward.w = HL2IVP(origin.x);
// This vector is supposed to be left, so we'll negate it later, but we don't want to
// negate the position, so add another minus to cancel out
right.w = -HL2IVP(origin.y);
up.w = HL2IVP(origin.z);
fltx4 rx = ConvertDirectionToIVP(LoadAlignedSIMD(forward.Base()));
fltx4 ry = ConvertDirectionToIVP(SubSIMD( Four_Zeros, LoadAlignedSIMD(right.Base())) );
fltx4 rz = ConvertDirectionToIVP(LoadAlignedSIMD(up.Base()) );
fltx4 scaleHL = ReplicateX4(IVP2HL(1.0f));
m_ivpLocalToHLWorld.x = MulSIMD( scaleHL, rx );
m_ivpLocalToHLWorld.y = MulSIMD( scaleHL, ry );
m_ivpLocalToHLWorld.z = MulSIMD( scaleHL, rz );
#else
ConvertRotationToIVP( angles, m_matrix );
ConvertPositionToIVP( origin, m_matrix.vv );
float scale = IVP2HL(1.0f);
float negScale = IVP2HL(-1.0f);
// copy the existing IVP local->world matrix (swap Y & Z)
m_ivpLocalToHLWorld.m_flMatVal[0][0] = m_matrix.get_elem(IVP_INDEX_X,0) * scale;
m_ivpLocalToHLWorld.m_flMatVal[0][1] = m_matrix.get_elem(IVP_INDEX_X,1) * scale;
m_ivpLocalToHLWorld.m_flMatVal[0][2] = m_matrix.get_elem(IVP_INDEX_X,2) * scale;
m_ivpLocalToHLWorld.m_flMatVal[1][0] = m_matrix.get_elem(IVP_INDEX_Z,0) * scale;
m_ivpLocalToHLWorld.m_flMatVal[1][1] = m_matrix.get_elem(IVP_INDEX_Z,1) * scale;
m_ivpLocalToHLWorld.m_flMatVal[1][2] = m_matrix.get_elem(IVP_INDEX_Z,2) * scale;
m_ivpLocalToHLWorld.m_flMatVal[2][0] = m_matrix.get_elem(IVP_INDEX_Y,0) * negScale;
m_ivpLocalToHLWorld.m_flMatVal[2][1] = m_matrix.get_elem(IVP_INDEX_Y,1) * negScale;
m_ivpLocalToHLWorld.m_flMatVal[2][2] = m_matrix.get_elem(IVP_INDEX_Y,2) * negScale;
m_ivpLocalToHLWorld.m_flMatVal[0][3] = m_matrix.vv.k[0] * scale;
m_ivpLocalToHLWorld.m_flMatVal[1][3] = m_matrix.vv.k[2] * scale;
m_ivpLocalToHLWorld.m_flMatVal[2][3] = m_matrix.vv.k[1] * negScale;
#endif
m_radius = ConvertDistanceToHL( m_pSurface->upper_limit_radius + centerOffset );
}
bool CTraceIVP::BuildLeafmapCacheRLE( const leafmap_t * RESTRICT pLeafmap )
{
// iterate the rle spans of verts and output them to a buffer in post-transform space
int startPoint = pLeafmap->startVert[0];
int pointCount = pLeafmap->vertCount;
m_cacheCount = (pointCount + 3)>>2;
const byte *RESTRICT pSpans = pLeafmap->GetSpans();
int countThisSpan = pSpans[0];
int spanIndex = 1;
int baseVert = 0;
const VectorAligned * RESTRICT pVerts = (const VectorAligned *)&m_pLedge->get_point_array()[startPoint];
for ( int i = 0; i < m_cacheCount-1; i++ )
{
if ( countThisSpan < 4 )
{
// unrolled for perf
// we need a batch of four verts, but they aren't in a single span
int v0, v1, v2, v3;
if ( !countThisSpan )
{
baseVert += pSpans[spanIndex];
countThisSpan = pSpans[spanIndex+1];
spanIndex += 2;
}
v0 = baseVert++;
countThisSpan--;
if ( !countThisSpan )
{
baseVert += pSpans[spanIndex];
countThisSpan = pSpans[spanIndex+1];
spanIndex += 2;
}
v1 = baseVert++;
countThisSpan--;
if ( !countThisSpan )
{
baseVert += pSpans[spanIndex];
countThisSpan = pSpans[spanIndex+1];
spanIndex += 2;
}
v2 = baseVert++;
countThisSpan--;
if ( !countThisSpan )
{
baseVert += pSpans[spanIndex];
countThisSpan = pSpans[spanIndex+1];
spanIndex += 2;
}
v3 = baseVert++;
countThisSpan--;
m_vertCache[i].LoadAndSwizzleAligned( pVerts[v0].Base(), pVerts[v1].Base(), pVerts[v2].Base(), pVerts[v3].Base() );
}
else
{
// we have four verts in this span, just grab the next four
m_vertCache[i].LoadAndSwizzleAligned( pVerts[baseVert+0].Base(), pVerts[baseVert+1].Base(), pVerts[baseVert+2].Base(), pVerts[baseVert+3].Base() );
baseVert += 4;
countThisSpan -= 4;
}
}
// the last iteration needs multiple spans and clamping to the last vert
int v[4];
for ( int i = 0; i < 4; i++ )
{
if ( spanIndex < pLeafmap->spanCount && !countThisSpan )
{
baseVert += pSpans[spanIndex];
countThisSpan = pSpans[spanIndex+1];
spanIndex += 2;
}
if ( spanIndex < pLeafmap->spanCount )
{
v[i] = baseVert;
baseVert++;
countThisSpan--;
}
else
{
v[i] = baseVert;
if ( countThisSpan > 1 )
{
countThisSpan--;
baseVert++;
}
}
}
m_vertCache[m_cacheCount-1].LoadAndSwizzleAligned( pVerts[v[0]].Base(), pVerts[v[1]].Base(), pVerts[v[2]].Base(), pVerts[v[3]].Base() );
FourVectors::RotateManyBy( &m_vertCache[0], m_cacheCount, *((const matrix3x4_t *)&m_ivpLocalToHLWorld) );
return true;
}
bool CTraceIVP::BuildLeafmapCache( const leafmap_t * RESTRICT pLeafmap )
{
#if !USE_VERT_CACHE
return false;
#else
if ( !pLeafmap || !pLeafmap->HasSpans() || m_bHasTranslation )
return false;
if ( pLeafmap->HasRLESpans() )
{
return BuildLeafmapCacheRLE(pLeafmap);
}
// single vertex span, just xform + copy
// iterate the span of verts and output them to a buffer in post-transform space
// just iterate the range if one is specified
int startPoint = pLeafmap->startVert[0];
int pointCount = pLeafmap->vertCount;
m_cacheCount = (pointCount + 3)>>2;
Assert(m_cacheCount>=0 && m_cacheCount<= (BRUTE_FORCE_VERT_COUNT/4));
const VectorAligned * RESTRICT pVerts = (const VectorAligned *)&m_pLedge->get_point_array()[startPoint];
for ( int i = 0; i < m_cacheCount-1; i++ )
{
m_vertCache[i].LoadAndSwizzleAligned( pVerts[0].Base(), pVerts[1].Base(), pVerts[2].Base(), pVerts[3].Base() );
pVerts += 4;
}
int remIndex = (pointCount-1) & 3;
int x0 = 0;
int x1 = min(1,remIndex);
int x2 = min(2,remIndex);
int x3 = min(3,remIndex);
m_vertCache[m_cacheCount-1].LoadAndSwizzleAligned( pVerts[x0].Base(), pVerts[x1].Base(), pVerts[x2].Base(), pVerts[x3].Base() );
FourVectors::RotateManyBy( &m_vertCache[0], m_cacheCount, *((const matrix3x4_t *)&m_ivpLocalToHLWorld) );
return true;
#endif
}
static const fltx4 g_IndexBase = {0,1,2,3};
int CTraceIVP::SupportMapCached( const Vector &dir, Vector *pOut ) const
{
VPROF("SupportMapCached");
#if USE_VERT_CACHE
FourVectors fourDir;
#if defined(_X360)
fltx4 vec = LoadUnaligned3SIMD( dir.Base() );
fourDir.x = SplatXSIMD(vec);
fourDir.y = SplatYSIMD(vec);
fourDir.z = SplatZSIMD(vec);
#else
fourDir.DuplicateVector(dir);
#endif
fltx4 index = g_IndexBase;
fltx4 maxIndex = g_IndexBase;
fltx4 maxDot = fourDir * m_vertCache[0];
for ( int i = 1; i < m_cacheCount; i++ )
{
index = AddSIMD(index, Four_Fours);
fltx4 dot = fourDir * m_vertCache[i];
fltx4 cmpMask = CmpGtSIMD(dot,maxDot);
maxIndex = MaskedAssign( cmpMask, index, maxIndex );
maxDot = MaxSIMD(dot, maxDot);
}
// find highest of 4
fltx4 rot = RotateLeft2(maxDot);
fltx4 rotIndex = RotateLeft2(maxIndex);
fltx4 cmpMask = CmpGtSIMD(rot,maxDot);
maxIndex = MaskedAssign(cmpMask, rotIndex, maxIndex);
maxDot = MaxSIMD(rot,maxDot);
rotIndex = RotateLeft(maxIndex);
rot = RotateLeft(maxDot);
cmpMask = CmpGtSIMD(rot,maxDot);
maxIndex = MaskedAssign(cmpMask, rotIndex, maxIndex);
// not needed unless we need the actual max dot at the end
// maxDot = MaxSIMD(rot,maxDot);
int bestIndex = SubFloatConvertToInt(maxIndex,0);
*pOut = CachedVertByIndex(bestIndex);
return bestIndex;
#else
Assert(0);
#endif
}
int CTraceIVP::SupportMap( const Vector &dir, Vector *pOut ) const
{
#if USE_VERT_CACHE
if ( m_cacheCount )
return SupportMapCached( dir, pOut );
#endif
if ( m_pLeafmap && m_pLeafmap->HasSingleVertexSpan() )
{
VPROF("SupportMap_Leaf");
const IVP_U_Float_Point *pPoints = m_pLedge->get_point_array();
IVP_U_Float_Point mapdir;
TransformDirectionToLocal( dir, mapdir );
// just iterate the range if one is specified
int startPoint = m_pLeafmap->startVert[0];
int pointCount = m_pLeafmap->vertCount;
float bestDot = pPoints[startPoint].dot_product(&mapdir);
int best = startPoint;
for ( int i = 1; i < pointCount; i++ )
{
float dot = pPoints[startPoint+i].dot_product(&mapdir);
if ( dot > bestDot )
{
bestDot = dot;
best = startPoint+i;
}
}
TransformPositionFromLocal( pPoints[best], *pOut ); // transform point position to world space
return best;
}
else
{
VPROF("SupportMap_Walk");
const IVP_U_Float_Point *pPoints = m_pLedge->get_point_array();
IVP_U_Float_Point mapdir;
TransformDirectionToLocal( dir, mapdir );
int triCount = m_pLedge->get_n_triangles();
Assert( m_pVisitHash );
m_pVisitHash->NewVisit();
float dot;
int triIndex = 0, edgeIndex = 0;
GetStartVert( m_pLeafmap, mapdir, triIndex, edgeIndex );
const IVP_Compact_Triangle *RESTRICT pTri = m_pLedge->get_first_triangle() + triIndex;
const IVP_Compact_Edge *RESTRICT pEdge = pTri->get_edge( edgeIndex );
int best = pEdge->get_start_point_index();
float bestDot = pPoints[best].dot_product( &mapdir );
m_pVisitHash->VisitVert(best);
// This should never happen. MAX_CONVEX_VERTS is very large (millions), none of our
// models have anywhere near this many verts in a convex piece
Assert(triCount*3<MAX_CONVEX_VERTS);
// this loop will early out, but keep it from being infinite
for ( int i = 0; i < triCount; i++ )
{
// get the index to the end vert of this edge (start vert on next edge)
pEdge = pEdge->get_prev();
int stopVert = pEdge->get_start_point_index();
// loop through the verts that can be reached along edges from this vert
// stop if you get back to the one you're starting on.
int vert = stopVert;
do
{
if ( !m_pVisitHash->WasVisited(vert) )
{
// this lets us skip doing dot products on this vert
m_pVisitHash->VisitVert(vert);
dot = pPoints[vert].dot_product( &mapdir );
if ( dot > bestDot )
{
bestDot = dot;
best = vert;
break;
}
}
// tri opposite next edge, same starting vert as next edge
pEdge = pEdge->get_opposite()->get_prev();
vert = pEdge->get_start_point_index();
} while ( vert != stopVert );
// if you exhausted the possibilities for this vert, it must be the best vert
if ( vert != best )
break;
}
// code to do the brute force method with no hill-climbing
#if 0
for ( i = 0; i < triCount; i++ )
{
pTri = m_pLedge->get_first_triangle() + i;
for ( int j = 0; j < 3; j++ )
{
pEdge = pTri->get_edge( j );
int test = pEdge->get_start_point_index();
dot = pPoints[test].dot_product( &mapdir );
if ( dot > bestDot )
{
Assert(0); // shouldn't hit this unless the hill-climb is broken
bestDot = dot;
best = test;
}
}
}
#endif
TransformPositionFromLocal( pPoints[best], *pOut ); // transform point position to world space
return best;
}
}
Vector CTraceIVP::GetVertByIndex( int index ) const
{
#if USE_VERT_CACHE
if ( m_cacheCount )
{
return CachedVertByIndex(index);
}
#endif
const IVP_Compact_Poly_Point *pPoints = m_pLedge->get_point_array();
Vector out;
TransformPositionFromLocal( pPoints[index], out );
return out;
}
//-----------------------------------------------------------------------------
// Purpose: Implementation for Trace against an AABB
//-----------------------------------------------------------------------------
class CTraceAABB : public ITraceObject
{
public:
CTraceAABB( const Vector &hlmins, const Vector &hlmaxs, bool isPoint );
virtual int SupportMap( const Vector &dir, Vector *pOut ) const;
virtual Vector GetVertByIndex( int index ) const;
virtual float Radius( void ) const { return m_radius; }
private:
float m_x[2];
float m_y[2];
float m_z[2];
float m_radius;
bool m_empty;
};
CTraceAABB::CTraceAABB( const Vector &hlmins, const Vector &hlmaxs, bool isPoint )
{
if ( isPoint )
{
m_x[0] = m_x[1] = 0;
m_y[0] = m_y[1] = 0;
m_z[0] = m_z[1] = 0;
m_radius = 0;
m_empty = true;
}
else
{
m_x[0] = hlmaxs[0];
m_x[1] = hlmins[0];
m_y[0] = hlmaxs[1];
m_y[1] = hlmins[1];
m_z[0] = hlmaxs[2];
m_z[1] = hlmins[2];
m_radius = hlmaxs.Length();
m_empty = false;
}
}
int CTraceAABB::SupportMap( const Vector &dir, Vector *pOut ) const
{
Vector out;
if ( m_empty )
{
pOut->Init();
return 0;
}
// index is formed by the 3-bit bitfield SzSySx (negative is 1, positive is 0)
int x = ((*((unsigned int *)&dir.x)) & 0x80000000UL) >> 31;
int y = ((*((unsigned int *)&dir.y)) & 0x80000000UL) >> 31;
int z = ((*((unsigned int *)&dir.z)) & 0x80000000UL) >> 31;
pOut->x = m_x[x];
pOut->y = m_y[y];
pOut->z = m_z[z];
return (z<<2) | (y<<1) | x;
}
Vector CTraceAABB::GetVertByIndex( int index ) const
{
Vector out;
out.x = m_x[(index&1)];
out.y = m_y[(index&2)>>1];
out.z = m_z[(index&4)>>2];
return out;
}
//-----------------------------------------------------------------------------
// Purpose: Implementation for Trace against an IVP object
//-----------------------------------------------------------------------------
class CTraceRay
{
public:
CTraceRay( const Vector &hlstart, const Vector &hlend );
CTraceRay( const Ray_t &ray );
CTraceRay( const Ray_t &ray, const Vector &offset );
void Init( const Vector &hlstart, const Vector &delta );
int SupportMap( const Vector &dir, Vector *pOut ) const;
Vector GetVertByIndex( int index ) const { return ( index ) ? m_end : m_start; }
float Radius( void ) const { return m_length * 0.5f; }
void Reset( float fraction );
Vector m_start;
Vector m_end;
Vector m_delta;
Vector m_dir;
float m_length;
float m_baseLength;
float m_ooBaseLength;
float m_bestDist;
};
CTraceRay::CTraceRay( const Vector &hlstart, const Vector &hlend )
{
Init(hlstart, hlend-hlstart);
}
void CTraceRay::Init( const Vector &hlstart, const Vector &delta )
{
m_start = hlstart;
m_end = hlstart + delta;
m_delta = delta;
m_dir = delta;
float len = DotProduct(delta, delta);
// don't use fast/sse sqrt here we need the precision
m_length = sqrt(len);
m_ooBaseLength = 0.0f;
if ( m_length > 0 )
{
m_ooBaseLength = 1.0f / m_length;
m_dir *= m_ooBaseLength;
}
m_baseLength = m_length;
m_bestDist = 0.f;
}
CTraceRay::CTraceRay( const Ray_t &ray )
{
Init( ray.m_Start, ray.m_Delta );
}
CTraceRay::CTraceRay( const Ray_t &ray, const Vector &offset )
{
Vector start;
VectorAdd( ray.m_Start, offset, start );
Init( start, ray.m_Delta );
}
void CTraceRay::Reset( float fraction )
{
// recompute from base values for max precision
m_length = m_baseLength * fraction;
m_end = m_start + fraction * m_delta;
m_bestDist = 0.f;
}
int CTraceRay::SupportMap( const Vector &dir, Vector *pOut ) const
{
if ( DotProduct( dir, m_delta ) > 0 )
{
*pOut = m_end;
return 1;
}
*pOut = m_start;
return 0;
}
static char *map_nullname = "**empty**";
static csurface_t nullsurface = { map_nullname, 0 };
static void CM_ClearTrace( trace_t *trace )
{
memset( trace, 0, sizeof(*trace));
trace->fraction = 1.f;
trace->fractionleftsolid = 0;
trace->surface = nullsurface;
}
class CDefConvexInfo : public IConvexInfo
{
public:
IConvexInfo *GetPtr() { return this; }
virtual unsigned int GetContents( int convexGameData ) { return CONTENTS_SOLID; }
};
class CTraceSolver
{
public:
CTraceSolver( trace_t *ptr, ITraceObject *sweepobject, CTraceRay *ray, ITraceObject *obstacle, const Vector &axis )
{
m_pTotalTrace = ptr;
m_sweepObject = sweepobject;
m_sweepObjectRadius = m_sweepObject->Radius();
m_obstacle = obstacle;
m_ray = ray;
m_traceLength = 0;
m_totalTraceLength = max( ray->m_baseLength, 1e-8f );
m_pointClosestToIntersection = axis;
m_epsilon = g_PhysicsUnits.collisionSweepEpsilon;
}
bool SweepSingleConvex( void );
float SolveMeshIntersection( simplex_t &simplex );
float SolveMeshIntersection2D( simplex_t &simplex );
virtual void DoSweep( void )
{
SweepSingleConvex();
*m_pTotalTrace = m_trace;
}
void SetEpsilon( float epsilon )
{
m_epsilon = epsilon;
}
protected:
trace_t m_trace;
Vector m_pointClosestToIntersection;
ITraceObject *m_sweepObject;
ITraceObject *m_obstacle;
CTraceRay *m_ray;
trace_t *m_pTotalTrace;
float m_traceLength;
float m_totalTraceLength;
float m_sweepObjectRadius;
float m_epsilon;
private:
CTraceSolver( const CTraceSolver & );
};
class CTraceSolverSweptObject : public CTraceSolver
{
public:
CTraceSolverSweptObject( trace_t *ptr, ITraceObject *sweepobject, CTraceRay *ray, CTraceIVP *obstacle, const Vector &axis, unsigned int contentsMask, IConvexInfo *pConvexInfo );
void InitOSRay( void );
void SweepLedgeTree_r( const IVP_Compact_Ledgetree_Node *node );
inline bool SweepHitsSphereOS( const IVP_U_Float_Point *sphereCenter, float radius );
virtual void DoSweep( void );
inline void SweepAgainstNode( const IVP_Compact_Ledgetree_Node *node );
CTraceIVP *m_obstacleIVP;
IConvexInfo *m_pConvexInfo;
unsigned int m_contentsMask;
CDefConvexInfo m_fakeConvexInfo;
IVP_U_Float_Point m_rayCenterOS;
IVP_U_Float_Point m_rayStartOS;
IVP_U_Float_Point m_rayDirOS;
IVP_U_Float_Point m_rayDeltaOS;
float m_rayLengthOS;
private:
CTraceSolverSweptObject( const CTraceSolverSweptObject & ); // no implementation, quells compiler warning
};
CTraceSolverSweptObject::CTraceSolverSweptObject( trace_t *ptr, ITraceObject *sweepobject, CTraceRay *ray, CTraceIVP *obstacle, const Vector &axis, unsigned int contentsMask, IConvexInfo *pConvexInfo )
: CTraceSolver( ptr, sweepobject, ray, obstacle, axis )
{
m_obstacleIVP = obstacle;
m_contentsMask = contentsMask;
m_pConvexInfo = (pConvexInfo != NULL) ? pConvexInfo : m_fakeConvexInfo.GetPtr();
}
bool CTraceSolverSweptObject::SweepHitsSphereOS( const IVP_U_Float_Point *sphereCenter, float radius )
{
// disable this to help find bugs
#if DEBUG_TEST_ALL_LEDGES
return true;
#endif
// the ray is actually a line-swept-sphere with sweep object's radius
IVP_U_Float_Point delta_vec; // quick check for ends of ray
delta_vec.subtract( sphereCenter, &m_rayCenterOS );
radius += m_sweepObjectRadius;
// Is the sphere close enough to the ray at the center?
float qsphere_rad = radius * radius;
// If this is a 0 length ray, then the conservative test is 100% accurate
if ( m_rayLengthOS > 0 )
{
// Calculate the perpendicular distance to the sphere
// The perpendicular forms a right triangle with the vector between the ray/sphere centers
// and the ray direction vector. Calculate the projection of the hypoteneuse along the perpendicular
IVP_U_Float_Point h;
h.inline_calc_cross_product(&m_rayDirOS, &delta_vec);
if( h.quad_length() < qsphere_rad )
return true;
}
else
{
float quad_center_dist = delta_vec.quad_length();
if ( quad_center_dist < qsphere_rad )
{
return true;
}
// Could a ray in any direction away from the ray center intersect this sphere?
float qrad_sum = m_rayLengthOS * 0.5f + radius;
qrad_sum *= qrad_sum;
if ( quad_center_dist >= qrad_sum )
{
return false;
}
}
return false;
}
inline void CTraceSolverSweptObject::SweepAgainstNode(const IVP_Compact_Ledgetree_Node *node)
{
const IVP_Compact_Ledge *ledge = node->get_compact_ledge();
unsigned int ledgeContents = m_pConvexInfo->GetContents( ledge->get_client_data() );
if (m_contentsMask & ledgeContents)
{
m_obstacleIVP->SetLedge( ledge );
if ( SweepSingleConvex() )
{
if ( m_traceLength < m_totalTraceLength )
{
m_pTotalTrace->plane.normal = m_trace.plane.normal;
m_pTotalTrace->startsolid = m_trace.startsolid;
m_pTotalTrace->allsolid = m_trace.allsolid;
m_totalTraceLength = m_traceLength;
m_pTotalTrace->fraction = m_traceLength * m_ray->m_ooBaseLength;
Assert(m_pTotalTrace->fraction >= 0 && m_pTotalTrace->fraction <= 1.0f);
#if !DEBUG_KEEP_FULL_RAY
// shrink the ray to the shortened length, but leave a buffer of collisionSweepEpsilon units
// at the end to make sure that precision doesn't make you miss something slightly closer
float testFraction = (m_traceLength + m_epsilon*2) * m_ray->m_ooBaseLength;
if ( testFraction < 1.0f )
{
m_ray->Reset( testFraction );
// Update OS ray to limit tests
m_rayLengthOS = m_obstacleIVP->TransformLengthToLocal( m_ray->m_length );
m_rayCenterOS.add_multiple( &m_rayStartOS, &m_rayDeltaOS, 0.5f * testFraction );
}
#endif
m_pTotalTrace->contents = ledgeContents;
}
}
}
}
void CTraceSolverSweptObject::SweepLedgeTree_r( const IVP_Compact_Ledgetree_Node *node )
{
IVP_U_Float_Point center;
center.set(node->center.k);
if ( !SweepHitsSphereOS( &center, node->radius ) )
return;
// fast path for single leaf collision models
if ( node->is_terminal() == IVP_TRUE )
{
SweepAgainstNode(node);
return;
}
// use an array to implement a simple stack
CUtlVectorFixedGrowable<const IVP_Compact_Ledgetree_Node *, 64> list;
// pull the last item in the array (top of stack)
// this is nearly a priority queue, but not actually, but it's cheaper (and faster in the benchmarks)
// this code is trying to visit the nodes closest to the ray start first - which helps performance
// since we're only interested in the first intersection of the swept object with the physcollide.
while ( 1 )
{
// don't use the temp storage unless you have to.
loop_without_store:
if ( node->is_terminal() == IVP_TRUE )
{
// leaf, do the test
SweepAgainstNode(node);
}
else
{
// check node's children
const IVP_Compact_Ledgetree_Node *node0 = node->left_son();
center.set(node0->center.k);
// if we don't insert, this is larger than any quad distance
float lastDist = 1e16f;
if ( SweepHitsSphereOS( &center, node0->radius ) )
{
lastDist = m_rayStartOS.quad_distance_to(&center);
}
else
{
node0 = NULL;
}
const IVP_Compact_Ledgetree_Node *node1 = node->right_son();
center.set(node1->center.k);
if ( SweepHitsSphereOS( &center, node1->radius ) )
{
if ( node0 )
{
// can hit, push on stack
int index = list.AddToTail();
float dist1 = m_rayStartOS.quad_distance_to(&center);
if ( lastDist < dist1 )
{
node = node0;
list[index] = node1;
}
else
{
node = node1;
list[index] = node0;
}
}
else
{
node = node1;
}
goto loop_without_store;
}
if ( node0 )
{
node = node0;
goto loop_without_store;
}
}
int last = list.Count()-1;
if ( last < 0 )
break;
node = list[last];
list.FastRemove(last);
}
}
void CTraceSolverSweptObject::InitOSRay( void )
{
// transform ray into object space
m_rayLengthOS = m_obstacleIVP->TransformLengthToLocal( m_ray->m_length );
m_obstacleIVP->TransformPositionToLocal( m_ray->m_start, m_rayStartOS );
// no translation on matrix mult because this is a vector
m_obstacleIVP->RotateRelativePositionToLocal( m_ray->m_delta, m_rayDeltaOS );
m_rayDirOS.set(&m_rayDeltaOS);
m_rayDirOS.normize();
// add_multiple with 3 params assumes no initial value (should be set_add_multiple)
m_rayCenterOS.add_multiple( &m_rayStartOS, &m_rayDeltaOS, 0.5f );
}
void CTraceSolverSweptObject::DoSweep( void )
{
VPROF("TraceSolver::DoSweep");
InitOSRay();
// iterate ledge tree of obstacle
const IVP_Compact_Surface *pSurface = m_obstacleIVP->m_pSurface;
const IVP_Compact_Ledgetree_Node *lt_node_root;
lt_node_root = pSurface->get_compact_ledge_tree_root();
SweepLedgeTree_r( lt_node_root );
}
void CPhysicsTrace::SweepBoxIVP( const Vector &start, const Vector &end, const Vector &mins, const Vector &maxs, const CPhysCollide *pCollide, const Vector &surfaceOrigin, const QAngle &surfaceAngles, trace_t *ptr )
{
Ray_t ray;
ray.Init( start, end, mins, maxs );
SweepBoxIVP( ray, MASK_ALL, NULL, pCollide, surfaceOrigin, surfaceAngles, ptr );
}
void CPhysicsTrace::SweepBoxIVP( const Ray_t &raySrc, unsigned int contentsMask, IConvexInfo *pConvexInfo, const CPhysCollide *pCollide, const Vector &surfaceOrigin, const QAngle &surfaceAngles, trace_t *ptr )
{
CM_ClearTrace( ptr );
CTraceAABB box( -raySrc.m_Extents, raySrc.m_Extents, raySrc.m_IsRay );
CTraceIVP ivp( pCollide, vec3_origin, surfaceAngles );
// offset the space of this sweep so that the surface is at the origin of the solution space
CTraceRay ray( raySrc, -surfaceOrigin );
CTraceSolverSweptObject solver( ptr, &box, &ray, &ivp, ray.m_start, contentsMask, pConvexInfo );
solver.DoSweep();
VectorAdd( raySrc.m_Start, raySrc.m_StartOffset, ptr->startpos );
VectorMA( ptr->startpos, ptr->fraction, raySrc.m_Delta, ptr->endpos );
// The plane was shifted because we shifted everything over by surfaceOrigin, shift it back
if ( ptr->DidHit() )
{
ptr->plane.dist = DotProduct( ptr->endpos, ptr->plane.normal );
}
}
void CPhysicsTrace::SweepIVP( const Vector &start, const Vector &end, const CPhysCollide *pSweptSurface, const QAngle &sweptAngles, const CPhysCollide *pSurface, const Vector &surfaceOrigin, const QAngle &surfaceAngles, trace_t *ptr )
{
CM_ClearTrace( ptr );
CTraceIVP sweptObject( pSweptSurface, vec3_origin, sweptAngles );
// offset the space of this sweep so that the surface is at the origin of the solution space
CTraceIVP ivp( pSurface, vec3_origin, surfaceAngles );
CTraceRay ray( start - surfaceOrigin, end - surfaceOrigin );
IVP_U_BigVector<IVP_Compact_Ledge> objectLedges(32);
IVP_Compact_Ledge_Solver::get_all_ledges( pSweptSurface->GetCompactSurface(), &objectLedges );
for ( int i = objectLedges.len() - 1; i >= 0; --i )
{
trace_t tr;
CM_ClearTrace( &tr );
sweptObject.SetLedge( objectLedges.element_at(i) );
CTraceSolverSweptObject solver( &tr, &sweptObject, &ray, &ivp, start - surfaceOrigin, MASK_ALL, NULL );
// UNDONE: Need just more than 0.25" tolerance here because the output position will be used by vphysics
// UNDONE: Really this should be the collision radius from the environment.
solver.SetEpsilon( g_PhysicsUnits.globalCollisionTolerance );
solver.DoSweep();
if ( tr.fraction < ptr->fraction )
{
*ptr = tr;
}
}
ptr->endpos = start*(1.f-ptr->fraction) + end * ptr->fraction;
if ( ptr->DidHit() )
{
ptr->plane.dist = DotProduct( ptr->endpos, ptr->plane.normal );
}
}
static void CalculateSeparatingPlane( trace_t *ptr, ITraceObject *sweepObject, CTraceRay *ray, ITraceObject *obstacle, simplex_t &simplex );
//-----------------------------------------------------------------------------
// What is this doing? It's going to be hard to understand without reading a
// reference on the GJK algorithm. But here's a quick overview:
// Basically (remember this is glossing over a ton of details!) the
// algorithm is building up a simplex that is trying to contain the origin.
// A simplex is a point, line segment, triangle, or tetrahedron - depending on
// how many verts you have.
// Anyway it slowly builds one of these one vert at a time with a directed search.
// So you start out with a point, then it guesses the next point that would be
// most likely to form a line through the origin. If the line doesn't go quite
// through the origin it tries to find a third point to capture the origin
// within a triangle. If that doesn't work it tries to make a
// tent (tetrahedron) out of the triangle to capture the origin.
//
// But at each step if the origin is not contained within, it tries to
// find which sub-feature is most likely to be in the solution. In
// the point case it's always just the point. In the line/edge case it
// can reduce back to a point (origin is closest to one of the points)
// or be the line (origin is closest to some point between them).
// Same with the triangle (origin is closest to one vert - vert, origin is
// closest to one edge - reduce to that edge, origin is closes to some point
// in the triangle's surface - keep the whole triangle). With a tetrahedron
// keeping the whole isn't possible unless the origin is inside and you're
// done (the origin has been captured).
//
// "You're done" means that there is an intersection between the two
// volumes. Assuming you're testing a sweep, it still has to test whether that
// sweep can be shrunk back until there is no intersection. So it checks that.
// If it's a swept test so it does the search with SolveMeshIntersection
// Otherwise, there's nothing to shrink, so you set startsolid and allsolid
// because it's a point/box in solid test, not a swept box/ray hits solid test.
//
// Why is it trying to capture the origin? Basically GJK sets up a space
// and a convex hull (the minkowski sum) in that space. The convex hull
// represents a field of the distances between different features of the pair
// of objects (e.g. for two circles, this minkowski sum is just a circle).
// So the origin is the point in the field where the distance between the
// objects is zero. This means they intersect.
//-----------------------------------------------------------------------------
#if defined(_X360)
inline void VectorNormalize_FastLowPrecision( Vector &a )
{
float quad = (a.x*a.x) + (a.y*a.y) + (a.z*a.z);
float ilen = __frsqrte(quad);
a.x *= ilen;
a.y *= ilen;
a.z *= ilen;
}
#else
#define VectorNormalize_FastLowPrecision VectorNormalize
#endif
bool CTraceSolver::SweepSingleConvex( void )
{
VPROF("TraceSolver::SweepSingleConvex");
simplex_t simplex;
simplexvert_t vert;
Vector tmp;
simplex.vertCount = 0;
if ( m_pointClosestToIntersection == vec3_origin )
{
m_pointClosestToIntersection.Init(1,0,0);
}
float testLen = 1;
Vector dir = -m_pointClosestToIntersection;
VectorNormalize_FastLowPrecision(dir);
// safe loop, max 100 iterations
for ( int i = 0; i < 100; i++ )
{
// map the direction into the minkowski sum, get a new surface point
vert.testIndex = m_sweepObject->SupportMap( dir, &vert.position );
vert.sweepIndex = m_ray->SupportMap( dir, &tmp );
VectorAdd( vert.position, tmp, vert.position );
vert.obstacleIndex = m_obstacle->SupportMap( -dir, &tmp );
VectorSubtract( vert.position, tmp, vert.position );
testLen = DotProduct( dir, vert.position );
// found a separating axis, no intersection
if ( testLen < 0 )
{
VPROF("SolveSeparation");
// make sure we're separated by at least m_epsilon
testLen = fabs(testLen);
if ( testLen < m_epsilon && m_ray->m_length > 0 )
{
// not separated by enough
Vector normal = dir;
if ( testLen > 0 )
{
// try to find a better separating plane or clip the ray to the current one
for ( int j = 0; j < 20; j++ )
{
Vector lastVert = vert.position;
simplex.SolveGJKSet( vert, &m_pointClosestToIntersection );
dir = -m_pointClosestToIntersection;
VectorNormalize_FastLowPrecision( dir );
// map the direction into the minkowski sum, get a new surface point
vert.testIndex = m_sweepObject->SupportMap( dir, &vert.position );
vert.sweepIndex = m_ray->SupportMap( dir, &tmp );
VectorAdd( vert.position, tmp, vert.position );
vert.obstacleIndex = m_obstacle->SupportMap( -dir, &tmp );
VectorSubtract( vert.position, tmp, vert.position );
// found a separating axis, no intersection
float est = -DotProduct( dir, vert.position );
if ( est > m_epsilon ) // big enough separation, no hit
return false;
// take plane with the most separation
if ( est > testLen )
{
testLen = est;
normal = dir;
}
float last = -DotProduct( dir, lastVert );
// search is not converging, exit.
if ( (est - last) > -1e-4f )
break;
}
}
// This trace is going to miss, but not by enough.
// Hit the separating plane instead
float dot = -DotProduct( m_ray->m_delta, normal );
if ( dot < -(m_epsilon*0.1) || (dot < -1e-4f && testLen < (m_epsilon*0.9)) )
{
CM_ClearTrace( &m_trace );
float backupDistance = m_epsilon - testLen;
backupDistance = -(backupDistance * m_ray->m_baseLength) / dot;
m_traceLength = m_ray->m_length - backupDistance;
if ( m_traceLength < 0 )
{
m_traceLength = 0;
// try sliding along the surface of the minkowski sum
backupDistance = SolveMeshIntersection2D( simplex );
if ( m_ray->m_length > backupDistance )
{
m_traceLength = m_ray->m_length - backupDistance;
}
}
m_trace.plane.normal = -normal;
// this is fixed up by the outer code
//m_trace.endpos = m_ray->m_start*(1.f-m_trace.fraction) + m_ray->m_end*m_trace.fraction;
m_trace.contents = CONTENTS_SOLID;
return true;
}
}
return false;
}
// contains the origin
if ( simplex.SolveGJKSet( vert, &m_pointClosestToIntersection ) )
{
VPROF("TraceSolver::SolveMeshIntersection");
CM_ClearTrace( &m_trace );
// now solve for t along the sweep
if ( m_ray->m_length != 0 )
{
float dist = SolveMeshIntersection( simplex );
if ( dist < m_ray->m_length && dist > 0.f )
{
m_traceLength = (m_ray->m_length - dist);
CalculateSeparatingPlane( &m_trace, m_sweepObject, m_ray, m_obstacle, simplex );
float dot = DotProduct( m_ray->m_dir, m_trace.plane.normal );
if ( dot < 0 )
{
m_traceLength += (m_epsilon / dot);
}
if ( m_traceLength < 0 )
{
m_traceLength = 0;
}
//m_trace.fraction = m_traceLength * m_ray->m_ooBaseLength;
//m_trace.endpos = m_ray->m_start*(1.f-m_trace.fraction) + m_ray->m_end*m_trace.fraction;
m_trace.contents = CONTENTS_SOLID;
}
else
{
// UNDONE: This case happens when you start solid as well as when a false
// intersection is detected at the very end of the trace
m_trace.startsolid = true;
m_trace.allsolid = true;
m_traceLength = 0;
}
}
else
{
m_trace.startsolid = true;
m_trace.allsolid = true;
m_traceLength = 0;
}
return true;
}
dir = -m_pointClosestToIntersection;
VectorNormalize_FastLowPrecision( dir );
}
// BUGBUG: The solution never converged - something is probably wrong!
AssertMsg( false, "Solution never converged.");
return false;
}
// NEW SWEPT GJK SOLVER 2/16/2006
// convenience routines - just makes the code a little simpler.
FORCEINLINE bool simplex_t::TriangleSimplex( const simplexvert_t &newPoint, int outIndex, const Vector &faceNormal, Vector *pOut )
{
vertCount = 3;
verts[outIndex] = newPoint;
*pOut = -faceNormal;
return false;
}
FORCEINLINE bool simplex_t::EdgeSimplex( const simplexvert_t &newPoint, int outIndex, const Vector &edge, Vector *pOut )
{
vertCount = 2;
verts[outIndex] = newPoint;
Vector cross;
CrossProduct( edge, newPoint.position, cross );
CrossProduct( cross, edge, *pOut );
return false;
}
FORCEINLINE bool simplex_t::PointSimplex( const simplexvert_t &newPoint, Vector *pOut )
{
vertCount = 1;
verts[0] = newPoint;
*pOut = newPoint.position;
return false;
}
// In general the voronoi region routines have comments referring to the verts
// All of the code assumes that vert A is the new vert being added to the set
// verts B, C, D are the previous set. If BCD is a triangle it is assumed to be
// counter-clockwise winding order. This must be maintained by the code!
// parametric value for closes point on a line segment (p0->p1) to the origin.
bool simplex_t::SolveVoronoiRegion2( const simplexvert_t &newPoint, Vector *pOut )
{
// solve the line segment AB (where A is the new point)
Vector AB = verts[0].position - newPoint.position;
float d = DotProduct(AB, newPoint.position);
if ( d < 0 )
{
return EdgeSimplex(newPoint, 1, AB, pOut);
}
else
{
return PointSimplex(newPoint, pOut);
}
}
// UNDONE: Collapse these routines into a single general routine?
bool simplex_t::SolveVoronoiRegion3( const simplexvert_t &newPoint, Vector *pOut )
{
// solve the triangle ABC (where A is the new point)
Vector AB = verts[0].position - newPoint.position;
Vector AC = verts[1].position - newPoint.position;
Vector ABC;
CrossProduct(AB, AC, ABC);
Vector ABCxAC;
CrossProduct(ABC, AC, ABCxAC);
float d = DotProduct(ABCxAC, newPoint.position);
// edge AC or edgeAB / A?
if ( d < 0 )
{
d = DotProduct(AC, newPoint.position);
if ( d < 0 )
{
// edge AC
return EdgeSimplex(newPoint, 0, AC, pOut);
}
}
else
{
// face or A / edge AB?
Vector ABxABC;
CrossProduct(AB, ABC, ABxABC);
d = DotProduct(ABxABC, newPoint.position);
if ( d > 0 )
{
// closest to face
vertCount = 3;
d = DotProduct(ABC, newPoint.position);
// in front of face, return opposite direction
if ( d < 0 )
{
verts[2] = newPoint;
*pOut = -ABC;
return false;
}
verts[2] = verts[1]; // swap to keep CCW
verts[1] = newPoint;
*pOut = ABC;
return false;
}
}
// edge AB or A
d = DotProduct(AB, newPoint.position);
if ( d < 0 )
{
return EdgeSimplex(newPoint, 1, AB, pOut);
}
return PointSimplex(newPoint, pOut);
}
bool simplex_t::SolveVoronoiRegion4( const simplexvert_t &newPoint, Vector *pOut )
{
// solve the tetrahedron ABCD (where A is the new point)
// compute edge vectors
Vector AB = verts[0].position - newPoint.position;
Vector AC = verts[1].position - newPoint.position;
Vector AD = verts[2].position - newPoint.position;
// compute face normals
Vector ABC, ACD, ADB;
CrossProduct( AB, AC, ABC );
CrossProduct( AC, AD, ACD );
CrossProduct( AD, AB, ADB );
// edge plane normals
Vector ABCxAC, ABxABC;
CrossProduct( ABC, AC, ABCxAC );
CrossProduct( AB, ABC, ABxABC );
Vector ACDxAD, ACxACD;
CrossProduct( ACD, AD, ACDxAD );
CrossProduct( AC, ACD, ACxACD );
Vector ADBxAB, ADxADB;
CrossProduct( ADB, AB, ADBxAB );
CrossProduct( AD, ADB, ADxADB );
int faceFlags = 0;
float d;
d = DotProduct(ABC,newPoint.position);
if ( d < 0 )
{
faceFlags |= 0x1;
}
d = DotProduct(ACD,newPoint.position);
if ( d < 0 )
{
faceFlags |= 0x2;
}
d = DotProduct(ADB,newPoint.position);
if ( d < 0 )
{
faceFlags |= 0x4;
}
switch( faceFlags )
{
case 0:
// inside all 3 faces, we're done
verts[3] = newPoint;
vertCount = 4;
return true;
case 1:
// ABC only, solve as a triangle
return SolveVoronoiRegion3(newPoint, pOut);
case 2:
// ACD only, solve as a triangle
verts[0] = verts[2]; // collapse BCD to DC
return SolveVoronoiRegion3(newPoint, pOut);
case 4:
// ADB only, solve as a triangle
verts[1] = verts[2]; // collapse BCD to BD
return SolveVoronoiRegion3(newPoint, pOut);
case 3:
{
// in front of ABC & ACD
d = DotProduct(ABCxAC, newPoint.position);
if ( d < 0 )
{
d = DotProduct(ACxACD, newPoint.position);
if ( d < 0 )
{
d = DotProduct(AC,newPoint.position);
if ( d < 0 )
{
// edge AC
return EdgeSimplex( newPoint, 0, AC, pOut);
}
// point A
return PointSimplex(newPoint, pOut);
}
else
{
d = DotProduct(ACDxAD, newPoint.position);
if ( d < 0 )
{
// edge AD
verts[0] = verts[2]; // collapse BCD to D
return EdgeSimplex(newPoint, 1, AD, pOut);
}
// face ACD
return TriangleSimplex(newPoint,0,ACD, pOut);
}
}
else
{
d = DotProduct(ABxABC, newPoint.position);
if ( d < 0 )
{
d = DotProduct(AB, newPoint.position);
if ( d < 0 )
{
// edge AB
return EdgeSimplex(newPoint, 1, AB, pOut);
}
return PointSimplex(newPoint, pOut);
}
return TriangleSimplex(newPoint,2,ABC,pOut);
}
}
break;
case 5:
{
// in front of ADB & ABC
d = DotProduct(ADBxAB, newPoint.position);
if ( d < 0 )
{
d = DotProduct(ABxABC, newPoint.position);
if ( d < 0 )
{
d = DotProduct(AB,newPoint.position);
if ( d < 0 )
{
// edge AB
return EdgeSimplex( newPoint, 1, AB , pOut);
}
// point A
return PointSimplex(newPoint, pOut);
}
else
{
d = DotProduct(ABCxAC, newPoint.position);
if ( d < 0 )
{
// edge AC
return EdgeSimplex(newPoint, 0, AC, pOut);
}
// face ABC
return TriangleSimplex(newPoint,2,ABC,pOut);
}
}
else
{
d = DotProduct(ADxADB, newPoint.position);
if ( d < 0 )
{
d = DotProduct(AD, newPoint.position);
if ( d < 0 )
{
// edge AD
verts[0] = verts[2]; // collapse BCD to D
return EdgeSimplex(newPoint, 1, AD, pOut);
}
return PointSimplex(newPoint, pOut);
}
return TriangleSimplex(newPoint,1,ADB,pOut);
}
}
break;
case 6:
{
// in front of ACD & ADB
d = DotProduct(ACDxAD, newPoint.position);
if ( d < 0 )
{
d = DotProduct(ADxADB, newPoint.position);
if ( d < 0 )
{
d = DotProduct(AD,newPoint.position);
if ( d < 0 )
{
// edge AD
verts[0] = verts[2]; // collapse BCD to D
return EdgeSimplex(newPoint, 1, AD, pOut);
}
// point A
return PointSimplex(newPoint, pOut);
}
else
{
d = DotProduct(ADBxAB, newPoint.position);
if ( d < 0 )
{
// edge AB
return EdgeSimplex(newPoint, 1, AB, pOut);
}
// face ADB
return TriangleSimplex(newPoint,1,ADB, pOut);
}
}
else
{
d = DotProduct(ACxACD, newPoint.position);
if ( d < 0 )
{
d = DotProduct(AC, newPoint.position);
if ( d < 0 )
{
// edge AC
return EdgeSimplex(newPoint, 0, AC, pOut);
}
return PointSimplex(newPoint, pOut);
}
return TriangleSimplex(newPoint,0,ACD, pOut);
}
}
break;
case 7:
{
d = DotProduct(AB, newPoint.position);
if ( d < 0 )
{
return EdgeSimplex(newPoint, 1, AB, pOut);
}
else
{
d = DotProduct(AC, newPoint.position);
if ( d < 0 )
{
return EdgeSimplex(newPoint, 0, AC, pOut);
}
else
{
d = DotProduct(AD, newPoint.position);
if ( d < 0 )
{
verts[0] = verts[2]; // collapse BCD to D
return EdgeSimplex(newPoint, 1, AD, pOut);
}
return PointSimplex(newPoint, pOut);
}
}
}
}
verts[3] = newPoint;
vertCount = 4;
return true;
}
bool simplex_t::SolveGJKSet( const simplexvert_t &w, Vector *pOut )
{
VPROF("TraceSolver::simplex::SolveGJKSet");
#if 0
for ( int v = 0; v < vertCount; v++ )
{
for ( int v2 = v+1; v2 < vertCount; v2++ )
{
if ( (verts[v].obstacleIndex == verts[v2].obstacleIndex) &&
(verts[v].sweepIndex == verts[v2].sweepIndex) &&
(verts[v].testIndex == verts[v2].testIndex) )
{
// same vert in the list twice! degenerate
Assert(0);
}
}
}
#endif
switch( vertCount )
{
case 0:
vertCount = 1;
verts[0] = w;
*pOut = w.position;
return false;
case 1:
return SolveVoronoiRegion2( w, pOut );
case 2:
return SolveVoronoiRegion3( w, pOut );
case 3:
return SolveVoronoiRegion4( w, pOut );
}
return true;
}
void CalculateSeparatingPlane( trace_t *ptr, ITraceObject *sweepObject, CTraceRay *ray, ITraceObject *obstacle, simplex_t &simplex )
{
int testCount = 1, obstacleCount = 1;
unsigned int testIndex[4], obstacleIndex[4];
testIndex[0] = simplex.verts[0].testIndex;
obstacleIndex[0] = simplex.verts[0].obstacleIndex;
Assert( simplex.vertCount <= 4 );
int i, j;
for ( i = 1; i < simplex.vertCount; i++ )
{
for ( j = 0; j < obstacleCount; j++ )
{
if ( obstacleIndex[j] == simplex.verts[i].obstacleIndex )
break;
}
if ( j == obstacleCount )
{
obstacleIndex[obstacleCount++] = simplex.verts[i].obstacleIndex;
}
for ( j = 0; j < testCount; j++ )
{
if ( testIndex[j] == simplex.verts[i].testIndex )
break;
}
if ( j == testCount )
{
testIndex[testCount++] = simplex.verts[i].testIndex;
}
}
if ( simplex.vertCount < 3 )
{
if ( simplex.vertCount == 2 && testCount == 2 )
{
// edge / point
Vector t0 = sweepObject->GetVertByIndex( testIndex[0] );
Vector t1 = sweepObject->GetVertByIndex( testIndex[1] );
Vector edge = t1-t0;
Vector tangent = CrossProduct( edge, ray->m_delta );
ptr->plane.normal = CrossProduct( edge, tangent );
VectorNormalize( ptr->plane.normal );
ptr->plane.dist = DotProduct( t0 + ptr->endpos, ptr->plane.normal );
return;
}
}
if ( testCount == 3 )
{
// face / xxx
Vector t0 = sweepObject->GetVertByIndex( testIndex[0] );
Vector t1 = sweepObject->GetVertByIndex( testIndex[1] );
Vector t2 = sweepObject->GetVertByIndex( testIndex[2] );
ptr->plane.normal = CrossProduct( t1-t0, t2-t0 );
VectorNormalize( ptr->plane.normal );
if ( DotProduct( ptr->plane.normal, ray->m_delta ) > 0 )
{
ptr->plane.normal = -ptr->plane.normal;
}
ptr->plane.dist = DotProduct( t0 + ptr->endpos, ptr->plane.normal );
}
else if ( testCount == 2 && obstacleCount == 2 )
{
// edge / edge
Vector t0 = sweepObject->GetVertByIndex( testIndex[0] );
Vector t1 = sweepObject->GetVertByIndex( testIndex[1] );
Vector t2 = obstacle->GetVertByIndex( obstacleIndex[0] );
Vector t3 = obstacle->GetVertByIndex( obstacleIndex[1] );
ptr->plane.normal = CrossProduct( t1-t0, t3-t2 );
VectorNormalize( ptr->plane.normal );
if ( DotProduct( ptr->plane.normal, ray->m_delta ) > 0 )
{
ptr->plane.normal = -ptr->plane.normal;
}
ptr->plane.dist = DotProduct( t0 + ptr->endpos, ptr->plane.normal );
}
else if ( obstacleCount == 3 )
{
// xxx / face
Vector t0 = obstacle->GetVertByIndex( obstacleIndex[0] );
Vector t1 = obstacle->GetVertByIndex( obstacleIndex[1] );
Vector t2 = obstacle->GetVertByIndex( obstacleIndex[2] );
ptr->plane.normal = CrossProduct( t1-t0, t2-t0 );
VectorNormalize( ptr->plane.normal );
if ( DotProduct( ptr->plane.normal, ray->m_delta ) > 0 )
{
ptr->plane.normal = -ptr->plane.normal;
}
ptr->plane.dist = DotProduct( t0, ptr->plane.normal );
}
else
{
ptr->plane.normal = -ray->m_dir;
if ( simplex.vertCount )
{
ptr->plane.dist = DotProduct( ptr->plane.normal, obstacle->GetVertByIndex( simplex.verts[0].obstacleIndex ) );
}
else
ptr->plane.dist = 0.f;
}
}
// clip a direction vector to a plane (ray begins at the origin)
inline float Clip( const Vector &dir, const Vector &pos, const Vector &normal )
{
float dist = DotProduct(pos, normal);
float cosTheta = DotProduct(dir,normal);
if ( cosTheta > 0 )
return dist / cosTheta;
// parallel or not facing the plane
return 1e16f;
}
// This is the first iteration of solving time of intersection.
// It needs to test all 4 faces of the tetrahedron to find the one the ray leaves through
// this is done by finding the closest plane by clipping the ray to each plane
Vector simplex_t::ClipRayToTetrahedronBase( const Vector &dir )
{
Vector AB = verts[0].position - verts[3].position;
Vector AC = verts[1].position - verts[3].position;
Vector AD = verts[2].position - verts[3].position;
Vector BC = verts[1].position - verts[0].position;
Vector BD = verts[2].position - verts[0].position;
// compute face normals
Vector ABC, ACD, ADB, BCD;
CrossProduct( AB, AC, ABC );
CrossProduct( AC, AD, ACD );
CrossProduct( AD, AB, ADB );
CrossProduct( BD, BC, BCD ); // flipped to point out of the tetrahedron
// NOTE: These cancel out in the clipping equation
//VectorNormalize(ABC);
//VectorNormalize(ACD);
//VectorNormalize(ADB);
//VectorNormalize(BCD);
// Assert valid tetrahedron/winding order
#if CHECK_TOI_CALCS
Assert(DotProduct(verts[2].position, ABC) < DotProduct(verts[3].position, ABC ));
Assert(DotProduct(verts[0].position, ACD) < DotProduct(verts[3].position, ACD ));
Assert(DotProduct(verts[1].position, ADB) < DotProduct(verts[3].position, ADB ));
Assert(DotProduct(verts[3].position, BCD) < DotProduct(verts[0].position, BCD ));
#endif
float dists[4];
dists[0] = Clip( dir, verts[3].position, ABC );
dists[1] = Clip( dir, verts[3].position, ACD );
dists[2] = Clip( dir, verts[3].position, ADB );
dists[3] = Clip( dir, verts[0].position, BCD );
float dmin = dists[3];
int best = 3;
for ( int i = 0; i < 3; i++ )
{
if ( dists[i] < dmin )
{
best = i;
dmin = dists[i];
}
}
vertCount = 3;
// push back down to a triangle
// Note that we need to preserve winding so that the vector order assumptions above are still valid!
switch( best )
{
case 0:
verts[2] = verts[3];
return ABC;
case 1:
verts[0] = verts[3];
return ACD;
case 2:
verts[1] = verts[3];
return ADB;
case 3:
// swap 1 & 2
verts[3] = verts[1];
verts[1] = verts[2];
verts[2] = verts[3];
return BCD;
}
Assert(0); // failed!
return vec3_origin;
}
// for subsequent iterations you don't need to test one of the faces (face you previously left through)
// so only test the three faces involving the new point A
Vector simplex_t::ClipRayToTetrahedron( const Vector &dir )
{
Vector AB = verts[0].position - verts[3].position;
Vector AC = verts[1].position - verts[3].position;
Vector AD = verts[2].position - verts[3].position;
// compute face normals
Vector ABC, ACD, ADB;
CrossProduct( AB, AC, ABC );
CrossProduct( AC, AD, ACD );
CrossProduct( AD, AB, ADB );
// NOTE: These cancel out in the clipping equation
//VectorNormalize(ABC);
//VectorNormalize(ACD);
//VectorNormalize(ADB);
// Assert valid tetrahedron/winding order
#if CHECK_TOI_CALCS
Assert(DotProduct(verts[2].position, ABC) < DotProduct(verts[3].position, ABC ));
Assert(DotProduct(verts[0].position, ACD) < DotProduct(verts[3].position, ACD ));
Assert(DotProduct(verts[1].position, ADB) < DotProduct(verts[3].position, ADB ));
#endif
float dists[3];
dists[0] = Clip( dir, verts[3].position, ABC );
dists[1] = Clip( dir, verts[3].position, ACD );
dists[2] = Clip( dir, verts[3].position, ADB );
float dmin = dists[2];
int best = 2;
for ( int i = 0; i < 2; i++ )
{
if ( dists[i] < dmin )
{
best = i;
dmin = dists[i];
}
}
vertCount = 3;
// push back down to a triangle
// Note that we need to preserve winding so that the vector order assumptions above are still valid!
switch( best )
{
case 0:
verts[2] = verts[3];
return ABC;
case 1:
verts[0] = verts[3];
return ACD;
case 2:
verts[1] = verts[3];
return ADB;
}
return vec3_origin;
}
float simplex_t::ClipRayToTriangle( const Vector &dir, float epsilon )
{
Vector AB = verts[0].position - verts[2].position;
Vector AC = verts[1].position - verts[2].position;
Vector BC = verts[1].position - verts[0].position;
// compute face normal
Vector ABC;
CrossProduct( AB, AC, ABC ); // this points toward the origin
VectorNormalize(ABC);
Vector edgeAB, edgeAC, edgeBC;
// these should point out of the triangle
CrossProduct( AB, ABC, edgeAB );
CrossProduct( ABC, AC, edgeAC );
CrossProduct( BC, ABC, edgeBC );
// NOTE: These cancel out in the clipping equation
VectorNormalize(edgeAB);
VectorNormalize(edgeAC);
VectorNormalize(edgeBC);
#if CHECK_TOI_CALCS
Assert(DotProduct(verts[2].position, ABC) < 0); // points toward
// Assert valid triangle/winding order (all normals point away from the origin)
Assert(DotProduct(verts[2].position, edgeAB) > 0);
Assert(DotProduct(verts[2].position, edgeAC) > 0);
Assert(DotProduct(verts[0].position, edgeBC) > 0);
#endif
float dists[3];
dists[0] = Clip( dir, verts[0].position, edgeAB );
dists[1] = Clip( dir, verts[1].position, edgeAC );
dists[2] = Clip( dir, verts[1].position, edgeBC );
Vector *normals[3] = {&edgeAB, &edgeAC, &edgeBC};
float dmin = dists[0];
int best = 0;
if ( dists[1] < dmin )
{
dmin = dists[1];
best = 1;
}
if ( dists[2] < dmin )
{
best = 2;
dmin = dists[2];
}
float dot = DotProduct( dir, *normals[best] );
if ( dot <= 0 )
return 1e16f;
dmin += epsilon/dot;
return dmin;
}
// Solve for time of intersection along the sweep
// Do this by iteratively clipping the ray to the tetrahedron containing the origin
// when a triangle is found intersecting the ray, reduce the simplex to that triangle
// and then re-expand it to a tetrahedron using the support point normal to the triangle (away from the origin)
// iterate until no new points can be found. That's the surface of the sum.
float CTraceSolver::SolveMeshIntersection( simplex_t &simplex )
{
Vector tmp;
Assert( simplex.vertCount == 4 );
if ( simplex.vertCount < 4 )
return 0.0f;
Vector v = simplex.ClipRayToTetrahedronBase( m_ray->m_dir );
simplexvert_t vert;
// safe loop, max 100 iterations
for ( int i = 0; i < 100; i++ )
{
VectorNormalize(v);
vert.testIndex = m_sweepObject->SupportMap( v, &vert.position );
vert.sweepIndex = m_ray->SupportMap( v, &tmp );
VectorAdd( vert.position, tmp, vert.position );
vert.obstacleIndex = m_obstacle->SupportMap( -v, &tmp );
VectorSubtract( vert.position, tmp, vert.position );
// map the new separating axis (NOTE: This test is inverted from the GJK - we are trying to get out, not in)
// found a separating axis, we've moved the sweep back enough
float dist = DotProduct( v, simplex.verts[0].position ) + TEST_EPSILON;
if ( DotProduct( v, vert.position ) <= dist )
{
Vector BC = simplex.verts[1].position - simplex.verts[0].position;
Vector BD = simplex.verts[2].position - simplex.verts[0].position;
// compute face normals
Vector BCD;
CrossProduct( BC, BD, BCD );
// NOTE: This cancels out inside Clip()
//VectorNormalize( BCD );
// clip ray to triangle
return Clip( m_ray->m_dir, simplex.verts[0].position, BCD );
}
// add the new vert
simplex.verts[simplex.vertCount] = vert;
simplex.vertCount++;
v = simplex.ClipRayToTetrahedron( m_ray->m_dir );
}
Assert(0);
return 0.0f;
}
// similar to SolveMeshIntersection, but solves projected into the 2D triangle simplex remaining
// this is used for the near miss case
float CTraceSolver::SolveMeshIntersection2D( simplex_t &simplex )
{
AssertMsg( simplex.vertCount == 3, "simplex.vertCount != 3: %d", simplex.vertCount );
if ( simplex.vertCount != 3 )
return 0.0f;
// note: This should really do this iteratively in case the triangle is coplanar with another triangle that
// is between this one and the edge of the sum in this plane
float dist = simplex.ClipRayToTriangle( m_ray->m_dir, m_epsilon );
return dist;
}
static const Vector g_xpos(1,0,0), g_xneg(-1,0,0);
static const Vector g_ypos(0,1,0), g_yneg(0,-1,0);
static const Vector g_zpos(0,0,1), g_zneg(0,0,-1);
void TraceGetAABB_r( Vector *pMins, Vector *pMaxs, const IVP_Compact_Ledgetree_Node *node, CTraceIVP &ivp )
{
if ( node->is_terminal() == IVP_TRUE )
{
Vector tmp;
ivp.SetLedge( node->get_compact_ledge() );
ivp.SupportMap( g_xneg, &tmp );
AddPointToBounds( tmp, *pMins, *pMaxs );
ivp.SupportMap( g_yneg, &tmp );
AddPointToBounds( tmp, *pMins, *pMaxs );
ivp.SupportMap( g_zneg, &tmp );
AddPointToBounds( tmp, *pMins, *pMaxs );
ivp.SupportMap( g_xpos, &tmp );
AddPointToBounds( tmp, *pMins, *pMaxs );
ivp.SupportMap( g_ypos, &tmp );
AddPointToBounds( tmp, *pMins, *pMaxs );
ivp.SupportMap( g_zpos, &tmp );
AddPointToBounds( tmp, *pMins, *pMaxs );
return;
}
TraceGetAABB_r( pMins, pMaxs, node->left_son(), ivp );
TraceGetAABB_r( pMins, pMaxs, node->right_son(), ivp );
}
void CPhysicsTrace::GetAABB( Vector *pMins, Vector *pMaxs, const CPhysCollide *pCollide, const Vector &collideOrigin, const QAngle &collideAngles )
{
CTraceIVP ivp( pCollide, collideOrigin, collideAngles );
if ( ivp.SetSingleConvex() )
{
Vector tmp;
ivp.SupportMap( g_xneg, &tmp );
pMins->x = tmp.x;
ivp.SupportMap( g_yneg, &tmp );
pMins->y = tmp.y;
ivp.SupportMap( g_zneg, &tmp );
pMins->z = tmp.z;
ivp.SupportMap( g_xpos, &tmp );
pMaxs->x = tmp.x;
ivp.SupportMap( g_ypos, &tmp );
pMaxs->y = tmp.y;
ivp.SupportMap( g_zpos, &tmp );
pMaxs->z = tmp.z;
}
else
{
const IVP_Compact_Ledgetree_Node *lt_node_root;
lt_node_root = pCollide->GetCompactSurface()->get_compact_ledge_tree_root();
ClearBounds( *pMins, *pMaxs );
TraceGetAABB_r( pMins, pMaxs, lt_node_root, ivp );
}
// JAY: Disable this here, do it in the engine instead. That way the tools get
// accurate bboxes
#if 0
const float radius = g_PhysicsUnits.collisionSweepEpsilon;
mins -= Vector(radius,radius,radius);
maxs += Vector(radius,radius,radius);
#endif
}
void TraceGetExtent_r( const IVP_Compact_Ledgetree_Node *node, CTraceIVP &ivp, const Vector &dir, float &dot, Vector &point )
{
if ( node->is_terminal() == IVP_TRUE )
{
ivp.SetLedge( node->get_compact_ledge() );
Vector tmp;
ivp.SupportMap( dir, &tmp );
float newDot = DotProduct( tmp, dir );
if ( newDot > dot )
{
dot = newDot;
point = tmp;
}
return;
}
TraceGetExtent_r( node->left_son(), ivp, dir, dot, point );
TraceGetExtent_r( node->right_son(), ivp, dir, dot, point );
}
Vector CPhysicsTrace::GetExtent( const CPhysCollide *pCollide, const Vector &collideOrigin, const QAngle &collideAngles, const Vector &direction )
{
CTraceIVP ivp( pCollide, collideOrigin, collideAngles );
if ( ivp.SetSingleConvex() )
{
Vector tmp;
ivp.SupportMap( direction, &tmp );
return tmp;
}
else
{
const IVP_Compact_Ledgetree_Node *lt_node_root;
lt_node_root = pCollide->GetCompactSurface()->get_compact_ledge_tree_root();
Vector out = vec3_origin;
float tmp = -1e6f;
TraceGetExtent_r( lt_node_root, ivp, direction, tmp, out );
return out;
}
}
bool CPhysicsTrace::IsBoxIntersectingCone( const Vector &boxAbsMins, const Vector &boxAbsMaxs, const truncatedcone_t &cone )
{
trace_t tr;
CM_ClearTrace( &tr );
bool bPoint = (boxAbsMins == boxAbsMaxs) ? true : false;
CTraceAABB box( boxAbsMins - cone.origin, boxAbsMaxs - cone.origin, bPoint );
CTraceCone traceCone( cone, -cone.origin );
// offset the space of this sweep so that the surface is at the origin of the solution space
CTraceRay ray( vec3_origin, vec3_origin );
CTraceSolver solver( &tr, &box, &ray, &traceCone, boxAbsMaxs );
solver.DoSweep();
return tr.startsolid;
}
CPhysicsTrace::CPhysicsTrace()
{
}
CPhysicsTrace::~CPhysicsTrace()
{
}
CVisitHash::CVisitHash()
{
m_vertVisitID = 1;
memset( m_vertVisit, 0, sizeof(m_vertVisit) );
}