source-engine/movieobjects/dmmeshcomp.cpp

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2020-04-23 00:56:21 +08:00
//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Implementation of CDmMeshComp - CDmeMesh computation class
//
//=============================================================================
// Valve includes
#include "movieobjects/dmmeshcomp.h"
#include "movieobjects/dmefaceset.h"
#include "movieobjects/dmemesh.h"
#include "movieobjects/dmevertexdata.h"
// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"
//=============================================================================
//
//=============================================================================
CDmMeshComp::CDmMeshComp( CDmeMesh *pMesh, CDmeVertexData *pPassedBase )
: m_pMesh( pMesh )
, m_pBase( NULL )
{
m_pBase = pPassedBase ? pPassedBase : pMesh->GetCurrentBaseState();
if ( !m_pBase )
return;
const FieldIndex_t pIndex( m_pBase->FindFieldIndex( CDmeVertexData::FIELD_POSITION ) );
if ( pIndex < 0 )
return;
const CUtlVector< Vector > &pPositionData( m_pBase->GetPositionData() );
const CUtlVector<int> &pPositionIndices( m_pBase->GetVertexIndexData( CDmeVertexData::FIELD_POSITION ) );
const int nVertices( pPositionData.Count() );
if ( nVertices <= 0 )
return;
// Create vertices
// TODO: check for duplicates in pPositionData - that would break this algorithm
m_verts.EnsureCapacity( nVertices );
for ( int i = 0; i < nVertices; ++i )
{
const CUtlVector< int > &vertexIndices = m_pBase->FindVertexIndicesFromDataIndex( CDmeVertexData::FIELD_POSITION, i );
m_verts.AddToTail( new CVert( i, &vertexIndices, &pPositionData[ i ] ) );
}
// Create edges and faces
const int nFaceSets( pMesh->FaceSetCount() );
for ( int i = 0; i < nFaceSets; ++i )
{
CDmeFaceSet *pFaceSet( pMesh->GetFaceSet( i ) );
const int nIndices( pFaceSet->NumIndices() );
if ( nIndices < 4 ) // At least a triangle and a -1
continue;
m_faces.EnsureCapacity( m_faces.Count() + nIndices / 4 ); // # new faces <= nIndices/4 (tri + -1)
m_edges.EnsureCapacity( m_edges.Count() + nIndices / 2 ); // # new edges <= 2*new faces
int facePosIndex( -1 );
int edgePosIndex0( -1 );
int edgePosIndex1( -1 );
CUtlVector< CVert * > verts;
CUtlVector< CEdge * > edges;
CUtlVector< bool > edgeReverseMap;
bool bReverse = false;
for ( int j( 0 ); j < nIndices; ++j )
{
const int faceVertexIndex( pFaceSet->GetIndex( j ) );
if ( faceVertexIndex < 0 )
{
// End of face
edgePosIndex0 = edgePosIndex1;
edgePosIndex1 = facePosIndex;
Assert( edgePosIndex0 >= 0 );
Assert( edgePosIndex1 >= 0 );
edges.AddToTail( FindOrCreateEdge( edgePosIndex0, edgePosIndex1, &bReverse ) );
edgeReverseMap.AddToTail( bReverse );
CreateFace( verts, edges, edgeReverseMap );
facePosIndex = -1;
verts.RemoveAll();
edges.RemoveAll();
edgeReverseMap.RemoveAll();
continue;
}
if ( facePosIndex < 0 )
{
// First vertex
facePosIndex = pPositionIndices[ faceVertexIndex ];
edgePosIndex1 = facePosIndex;
verts.AddToTail( m_verts[ edgePosIndex1 ] );
continue;
}
// 2nd through last vertex
edgePosIndex0 = edgePosIndex1;
edgePosIndex1 = pPositionIndices[ faceVertexIndex ];
verts.AddToTail( m_verts[ edgePosIndex1 ] );
Assert( edgePosIndex0 >= 0 );
Assert( edgePosIndex1 >= 0 );
edges.AddToTail( FindOrCreateEdge( edgePosIndex0, edgePosIndex1, &bReverse ) );
edgeReverseMap.AddToTail( bReverse );
}
}
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
CDmMeshComp::~CDmMeshComp()
{
m_verts.PurgeAndDeleteElements();
m_edges.PurgeAndDeleteElements();
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
CDmMeshComp::CVert::CVert( int nPositionIndex, const CUtlVector< int > *pVertexIndices, const Vector *pPosition )
: m_positionIndex( nPositionIndex )
, m_pVertexIndices( pVertexIndices )
, m_pPosition( pPosition )
, m_edges( 8, 8 )
{
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
CDmMeshComp::CVert::CVert( const CVert &src )
: m_positionIndex( src.m_positionIndex )
, m_pVertexIndices( src.m_pVertexIndices )
, m_pPosition( src.m_pPosition )
, m_edges( 8, 8 )
{
m_edges.AddMultipleToTail( src.m_edges.Count(), src.m_edges.Base() );
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
int CDmMeshComp::CVert::PositionIndex() const
{
return m_positionIndex;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
const Vector *CDmMeshComp::CVert::Position() const
{
return m_pPosition;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
const CUtlVector< int > *CDmMeshComp::CVert::VertexIndices() const
{
return m_pVertexIndices;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
bool CDmMeshComp::CVert::operator==( const CVert &rhs ) const
{
return ( m_pPosition->DistToSqr( *rhs.m_pPosition ) < FLT_EPSILON );
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
CDmMeshComp::CEdge::CEdge()
: m_pVert0( NULL )
, m_pVert1( NULL )
, m_faceCount( 0 )
{
}
//-----------------------------------------------------------------------------
// Returns the vertex position index given the edge relative vertex index
//-----------------------------------------------------------------------------
int CDmMeshComp::CEdge::GetVertPositionIndex( int edgeRelativeVertexIndex ) const
{
if ( edgeRelativeVertexIndex == 0 && m_pVert0 )
return m_pVert0->PositionIndex();
if ( edgeRelativeVertexIndex == 1 && m_pVert1 )
return m_pVert1->PositionIndex();
return -1;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
CDmMeshComp::CVert *CDmMeshComp::CEdge::GetVert( int edgeRelativeVertexIndex ) const
{
if ( edgeRelativeVertexIndex == 0 )
return m_pVert0;
if ( edgeRelativeVertexIndex == 1 )
return m_pVert1;
return NULL;
}
//-----------------------------------------------------------------------------
// Returns true if the edge starts and stops at the same position in space
// The order of the vertices is not checked
//-----------------------------------------------------------------------------
bool CDmMeshComp::CEdge::operator==( const CEdge &rhs ) const
{
return (
( *m_pVert0 == *rhs.m_pVert0 && *m_pVert1 == *rhs.m_pVert1 ) ||
( *m_pVert0 == *rhs.m_pVert1 && *m_pVert1 == *rhs.m_pVert0 ) );
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
Vector CDmMeshComp::CEdge::EdgeVector() const
{
if ( m_pVert0 && m_pVert1 )
return *m_pVert1->Position() - *m_pVert0->Position();
return vec3_origin;
}
//-----------------------------------------------------------------------------
// Finds or Creates an edge... Can still return NULL if vertices do not exist
//-----------------------------------------------------------------------------
CDmMeshComp::CEdge *CDmMeshComp::FindOrCreateEdge( int vIndex0, int vIndex1, bool *pReverse /* = NULL */ )
{
CEdge *pEdge = FindEdge( vIndex0, vIndex1, pReverse );
if ( pEdge )
return pEdge;
CVert *pVert0 = m_verts[ vIndex0 ];
if ( pVert0 == NULL )
return NULL;
CVert *pVert1 = m_verts[ vIndex1 ];
if ( pVert1 == NULL )
return NULL;
pEdge = m_edges[ m_edges.AddToTail( new CEdge() ) ];
pEdge->m_pVert0 = pVert0;
pEdge->m_pVert1 = pVert1;
pVert0->m_edges.AddToTail( pEdge );
if ( vIndex0 != vIndex1 )
pVert1->m_edges.AddToTail( pEdge );
if ( pReverse )
{
*pReverse = false;
}
return pEdge;
}
//-----------------------------------------------------------------------------
// Returns the edge between vIndex0 & vIndex1 (or vice versa), NULL if not found
//-----------------------------------------------------------------------------
CDmMeshComp::CEdge *CDmMeshComp::FindEdge( int vIndex0, int vIndex1, bool *pReverse /* = NULL */ )
{
CUtlVector< CEdge * > &edges = m_verts[ vIndex0 ]->m_edges;
for ( int i = 0; i < edges.Count(); i++ )
{
CEdge *e = edges[ i ];
if ( e->GetVertPositionIndex( 0 ) == vIndex0 && e->GetVertPositionIndex( 1 ) == vIndex1 )
{
if ( pReverse )
{
*pReverse = false;
}
return e;
}
if ( e->GetVertPositionIndex( 1 ) == vIndex0 && e->GetVertPositionIndex( 0 ) == vIndex1 )
{
if ( pReverse )
{
*pReverse = true;
}
return e;
}
}
return NULL;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
CDmMeshComp::CFace *CDmMeshComp::CreateFace( const CUtlVector< CVert * > &verts, const CUtlVector< CEdge * > &edges, const CUtlVector< bool > &edgeReverseMap )
{
CFace *pFace = &m_faces[ m_faces.AddToTail() ];
pFace->m_verts.RemoveAll();
pFace->m_verts.AddVectorToTail( verts );
pFace->m_edges.RemoveAll();
pFace->m_edges.AddVectorToTail( edges );
pFace->m_edgeReverseMap.RemoveAll();
pFace->m_edgeReverseMap.AddVectorToTail( edgeReverseMap );
for ( int nEdgeIndex = edges.Count() - 1; nEdgeIndex >= 0; --nEdgeIndex )
{
edges[ nEdgeIndex ]->m_faceCount += 1;
}
return pFace;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
int CDmMeshComp::FindFacesWithVert( int vIndex, CUtlVector< CFace * > &faces )
{
// TODO: optimize this by adding a vector of face pointers to each vertex
faces.RemoveAll();
for ( int fi( m_faces.Head() ); fi != m_faces.InvalidIndex(); fi = m_faces.Next( fi ) )
{
CFace &face( m_faces[ fi ] );
for ( int i = 0; i < face.m_verts.Count(); ++i )
{
if ( face.m_verts[ i ]->PositionIndex() == vIndex )
{
faces.AddToTail( &face );
break;
}
}
}
return faces.Count();
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
int CDmMeshComp::FindNeighbouringVerts( int vIndex, CUtlVector< CVert * > &verts )
{
verts.RemoveAll();
const CUtlVector< CEdge * > & edges = m_verts[ vIndex ]->m_edges;
for ( int i = 0; i < edges.Count(); ++i )
{
CEdge *e = edges[ i ];
if ( e->GetVertPositionIndex( 0 ) == vIndex )
{
verts.AddToTail( e->GetVert( 1 ) );
}
else
{
verts.AddToTail( e->GetVert( 0 ) );
}
}
return verts.Count();
}
//-----------------------------------------------------------------------------
// Find all edges that are only used by 1 face
//-----------------------------------------------------------------------------
int CDmMeshComp::GetBorderEdges( CUtlVector< CUtlVector< CEdge * > > &borderEdgesList )
{
// TODO: optimize this by stepping from edge to edge to build chains, using CVert::m_edges
int retVal = 0;
borderEdgesList.RemoveAll();
bool connected;
for ( int ei = 0; ei < m_edges.Count(); ei++ )
{
CEdge *pEdge = m_edges[ ei ];
if ( pEdge->IsBorderEdge() )
{
++retVal;
connected = false;
for ( int i = borderEdgesList.Count() - 1; !connected && i >= 0; --i )
{
CUtlVector< CEdge * > &borderEdges = borderEdgesList[ i ];
for ( int j = borderEdges.Count() - 1; j >= 0; --j )
{
if ( borderEdges[ j ]->ConnectedTo( pEdge ) )
{
borderEdges.AddToTail( pEdge );
connected = true;
break;
}
}
}
if ( !connected )
{
CUtlVector< CEdge * > &borderEdges = borderEdgesList[ borderEdgesList.AddToTail() ];
borderEdges.AddToTail( pEdge );
}
}
}
// Shrink the borderEdgesList to minimum number required
bool anyConnected = false;
do
{
anyConnected = false;
for ( int i = borderEdgesList.Count() - 1; i >= 0; --i )
{
CUtlVector< CEdge * > &srcBorderEdges = borderEdgesList[ i ];
for ( int j = srcBorderEdges.Count() - 1; j >= 0; --j )
{
CEdge *pSrcEdge = srcBorderEdges[ j ];
connected = false;
for ( int k = 0; !connected && k < i; ++k )
{
CUtlVector< CEdge * > &dstBorderEdges = borderEdgesList[ k ];
for ( int l = dstBorderEdges.Count() - 1; l >= 0; --l )
{
if ( dstBorderEdges[ l ]->ConnectedTo( pSrcEdge ) )
{
connected = true;
anyConnected = true;
dstBorderEdges.AddToTail( pSrcEdge );
srcBorderEdges.Remove( j );
break;
}
}
}
}
if ( srcBorderEdges.Count() == 0 )
{
borderEdgesList.Remove( i );
}
}
} while( anyConnected );
return retVal;
}