303 lines
7.5 KiB
C++
303 lines
7.5 KiB
C++
|
/*
|
||
|
|
Bullet Continuous Collision Detection and Physics Library
|
||
|
|
Copyright (c) 2011 Advanced Micro Devices, Inc. http://bulletphysics.org
|
||
|
|
|
||
|
|
This software is provided 'as-is', without any express or implied warranty.
|
||
|
|
In no event will the authors be held liable for any damages arising from the use of this software.
|
||
|
|
Permission is granted to anyone to use this software for any purpose,
|
||
|
|
including commercial applications, and to alter it and redistribute it freely,
|
||
|
|
subject to the following restrictions:
|
||
|
|
|
||
|
|
1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
|
||
|
|
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
|
||
|
|
3. This notice may not be removed or altered from any source distribution.
|
||
|
|
*/
|
||
|
|
|
||
|
|
|
||
|
|
///This file was written by Erwin Coumans
|
||
|
|
///Separating axis rest based on work from Pierre Terdiman, see
|
||
|
|
///And contact clipping based on work from Simon Hobbs
|
||
|
|
|
||
|
|
#include "btConvexPolyhedron.h"
|
||
|
|
#include "LinearMath/btHashMap.h"
|
||
|
|
|
||
|
|
btConvexPolyhedron::btConvexPolyhedron()
|
||
|
|
{
|
||
|
|
|
||
|
|
}
|
||
|
|
btConvexPolyhedron::~btConvexPolyhedron()
|
||
|
|
{
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
inline bool IsAlmostZero(const btVector3& v)
|
||
|
|
{
|
||
|
|
if(fabsf(v.x())>1e-6 || fabsf(v.y())>1e-6 || fabsf(v.z())>1e-6) return false;
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
struct btInternalVertexPair
|
||
|
|
{
|
||
|
|
btInternalVertexPair(short int v0,short int v1)
|
||
|
|
:m_v0(v0),
|
||
|
|
m_v1(v1)
|
||
|
|
{
|
||
|
|
if (m_v1>m_v0)
|
||
|
|
btSwap(m_v0,m_v1);
|
||
|
|
}
|
||
|
|
short int m_v0;
|
||
|
|
short int m_v1;
|
||
|
|
int getHash() const
|
||
|
|
{
|
||
|
|
return m_v0+(m_v1<<16);
|
||
|
|
}
|
||
|
|
bool equals(const btInternalVertexPair& other) const
|
||
|
|
{
|
||
|
|
return m_v0==other.m_v0 && m_v1==other.m_v1;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
struct btInternalEdge
|
||
|
|
{
|
||
|
|
btInternalEdge()
|
||
|
|
:m_face0(-1),
|
||
|
|
m_face1(-1)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
short int m_face0;
|
||
|
|
short int m_face1;
|
||
|
|
};
|
||
|
|
|
||
|
|
//
|
||
|
|
|
||
|
|
#ifdef TEST_INTERNAL_OBJECTS
|
||
|
|
bool btConvexPolyhedron::testContainment() const
|
||
|
|
{
|
||
|
|
for(int p=0;p<8;p++)
|
||
|
|
{
|
||
|
|
btVector3 LocalPt;
|
||
|
|
if(p==0) LocalPt = m_localCenter + btVector3(m_extents[0], m_extents[1], m_extents[2]);
|
||
|
|
else if(p==1) LocalPt = m_localCenter + btVector3(m_extents[0], m_extents[1], -m_extents[2]);
|
||
|
|
else if(p==2) LocalPt = m_localCenter + btVector3(m_extents[0], -m_extents[1], m_extents[2]);
|
||
|
|
else if(p==3) LocalPt = m_localCenter + btVector3(m_extents[0], -m_extents[1], -m_extents[2]);
|
||
|
|
else if(p==4) LocalPt = m_localCenter + btVector3(-m_extents[0], m_extents[1], m_extents[2]);
|
||
|
|
else if(p==5) LocalPt = m_localCenter + btVector3(-m_extents[0], m_extents[1], -m_extents[2]);
|
||
|
|
else if(p==6) LocalPt = m_localCenter + btVector3(-m_extents[0], -m_extents[1], m_extents[2]);
|
||
|
|
else if(p==7) LocalPt = m_localCenter + btVector3(-m_extents[0], -m_extents[1], -m_extents[2]);
|
||
|
|
|
||
|
|
for(int i=0;i<m_faces.size();i++)
|
||
|
|
{
|
||
|
|
const btVector3 Normal(m_faces[i].m_plane[0], m_faces[i].m_plane[1], m_faces[i].m_plane[2]);
|
||
|
|
const btScalar d = LocalPt.dot(Normal) + m_faces[i].m_plane[3];
|
||
|
|
if(d>0.0f)
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
void btConvexPolyhedron::initialize()
|
||
|
|
{
|
||
|
|
|
||
|
|
btHashMap<btInternalVertexPair,btInternalEdge> edges;
|
||
|
|
|
||
|
|
btScalar TotalArea = 0.0f;
|
||
|
|
|
||
|
|
m_localCenter.setValue(0, 0, 0);
|
||
|
|
for(int i=0;i<m_faces.size();i++)
|
||
|
|
{
|
||
|
|
int numVertices = m_faces[i].m_indices.size();
|
||
|
|
int NbTris = numVertices;
|
||
|
|
for(int j=0;j<NbTris;j++)
|
||
|
|
{
|
||
|
|
int k = (j+1)%numVertices;
|
||
|
|
btInternalVertexPair vp(m_faces[i].m_indices[j],m_faces[i].m_indices[k]);
|
||
|
|
btInternalEdge* edptr = edges.find(vp);
|
||
|
|
btVector3 edge = m_vertices[vp.m_v1]-m_vertices[vp.m_v0];
|
||
|
|
edge.normalize();
|
||
|
|
|
||
|
|
bool found = false;
|
||
|
|
|
||
|
|
for (int p=0;p<m_uniqueEdges.size();p++)
|
||
|
|
{
|
||
|
|
|
||
|
|
if (IsAlmostZero(m_uniqueEdges[p]-edge) ||
|
||
|
|
IsAlmostZero(m_uniqueEdges[p]+edge))
|
||
|
|
{
|
||
|
|
found = true;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!found)
|
||
|
|
{
|
||
|
|
m_uniqueEdges.push_back(edge);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (edptr)
|
||
|
|
{
|
||
|
|
btAssert(edptr->m_face0>=0);
|
||
|
|
btAssert(edptr->m_face1<0);
|
||
|
|
edptr->m_face1 = i;
|
||
|
|
} else
|
||
|
|
{
|
||
|
|
btInternalEdge ed;
|
||
|
|
ed.m_face0 = i;
|
||
|
|
edges.insert(vp,ed);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef USE_CONNECTED_FACES
|
||
|
|
for(int i=0;i<m_faces.size();i++)
|
||
|
|
{
|
||
|
|
int numVertices = m_faces[i].m_indices.size();
|
||
|
|
m_faces[i].m_connectedFaces.resize(numVertices);
|
||
|
|
|
||
|
|
for(int j=0;j<numVertices;j++)
|
||
|
|
{
|
||
|
|
int k = (j+1)%numVertices;
|
||
|
|
btInternalVertexPair vp(m_faces[i].m_indices[j],m_faces[i].m_indices[k]);
|
||
|
|
btInternalEdge* edptr = edges.find(vp);
|
||
|
|
btAssert(edptr);
|
||
|
|
btAssert(edptr->m_face0>=0);
|
||
|
|
btAssert(edptr->m_face1>=0);
|
||
|
|
|
||
|
|
int connectedFace = (edptr->m_face0==i)?edptr->m_face1:edptr->m_face0;
|
||
|
|
m_faces[i].m_connectedFaces[j] = connectedFace;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
#endif//USE_CONNECTED_FACES
|
||
|
|
|
||
|
|
for(int i=0;i<m_faces.size();i++)
|
||
|
|
{
|
||
|
|
int numVertices = m_faces[i].m_indices.size();
|
||
|
|
int NbTris = numVertices-2;
|
||
|
|
|
||
|
|
const btVector3& p0 = m_vertices[m_faces[i].m_indices[0]];
|
||
|
|
for(int j=1;j<=NbTris;j++)
|
||
|
|
{
|
||
|
|
int k = (j+1)%numVertices;
|
||
|
|
const btVector3& p1 = m_vertices[m_faces[i].m_indices[j]];
|
||
|
|
const btVector3& p2 = m_vertices[m_faces[i].m_indices[k]];
|
||
|
|
btScalar Area = ((p0 - p1).cross(p0 - p2)).length() * 0.5f;
|
||
|
|
btVector3 Center = (p0+p1+p2)/3.0f;
|
||
|
|
m_localCenter += Area * Center;
|
||
|
|
TotalArea += Area;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
m_localCenter /= TotalArea;
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
#ifdef TEST_INTERNAL_OBJECTS
|
||
|
|
if(1)
|
||
|
|
{
|
||
|
|
m_radius = FLT_MAX;
|
||
|
|
for(int i=0;i<m_faces.size();i++)
|
||
|
|
{
|
||
|
|
const btVector3 Normal(m_faces[i].m_plane[0], m_faces[i].m_plane[1], m_faces[i].m_plane[2]);
|
||
|
|
const btScalar dist = btFabs(m_localCenter.dot(Normal) + m_faces[i].m_plane[3]);
|
||
|
|
if(dist<m_radius)
|
||
|
|
m_radius = dist;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
btScalar MinX = FLT_MAX;
|
||
|
|
btScalar MinY = FLT_MAX;
|
||
|
|
btScalar MinZ = FLT_MAX;
|
||
|
|
btScalar MaxX = -FLT_MAX;
|
||
|
|
btScalar MaxY = -FLT_MAX;
|
||
|
|
btScalar MaxZ = -FLT_MAX;
|
||
|
|
for(int i=0; i<m_vertices.size(); i++)
|
||
|
|
{
|
||
|
|
const btVector3& pt = m_vertices[i];
|
||
|
|
if(pt.x()<MinX) MinX = pt.x();
|
||
|
|
if(pt.x()>MaxX) MaxX = pt.x();
|
||
|
|
if(pt.y()<MinY) MinY = pt.y();
|
||
|
|
if(pt.y()>MaxY) MaxY = pt.y();
|
||
|
|
if(pt.z()<MinZ) MinZ = pt.z();
|
||
|
|
if(pt.z()>MaxZ) MaxZ = pt.z();
|
||
|
|
}
|
||
|
|
mC.setValue(MaxX+MinX, MaxY+MinY, MaxZ+MinZ);
|
||
|
|
mE.setValue(MaxX-MinX, MaxY-MinY, MaxZ-MinZ);
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
// const btScalar r = m_radius / sqrtf(2.0f);
|
||
|
|
const btScalar r = m_radius / sqrtf(3.0f);
|
||
|
|
const int LargestExtent = mE.maxAxis();
|
||
|
|
const btScalar Step = (mE[LargestExtent]*0.5f - r)/1024.0f;
|
||
|
|
m_extents[0] = m_extents[1] = m_extents[2] = r;
|
||
|
|
m_extents[LargestExtent] = mE[LargestExtent]*0.5f;
|
||
|
|
bool FoundBox = false;
|
||
|
|
for(int j=0;j<1024;j++)
|
||
|
|
{
|
||
|
|
if(testContainment())
|
||
|
|
{
|
||
|
|
FoundBox = true;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
m_extents[LargestExtent] -= Step;
|
||
|
|
}
|
||
|
|
if(!FoundBox)
|
||
|
|
{
|
||
|
|
m_extents[0] = m_extents[1] = m_extents[2] = r;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Refine the box
|
||
|
|
const btScalar Step = (m_radius - r)/1024.0f;
|
||
|
|
const int e0 = (1<<LargestExtent) & 3;
|
||
|
|
const int e1 = (1<<e0) & 3;
|
||
|
|
|
||
|
|
for(int j=0;j<1024;j++)
|
||
|
|
{
|
||
|
|
const btScalar Saved0 = m_extents[e0];
|
||
|
|
const btScalar Saved1 = m_extents[e1];
|
||
|
|
m_extents[e0] += Step;
|
||
|
|
m_extents[e1] += Step;
|
||
|
|
|
||
|
|
if(!testContainment())
|
||
|
|
{
|
||
|
|
m_extents[e0] = Saved0;
|
||
|
|
m_extents[e1] = Saved1;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
void btConvexPolyhedron::project(const btTransform& trans, const btVector3& dir, btScalar& minProj, btScalar& maxProj, btVector3& witnesPtMin,btVector3& witnesPtMax) const
|
||
|
|
{
|
||
|
|
minProj = FLT_MAX;
|
||
|
|
maxProj = -FLT_MAX;
|
||
|
|
int numVerts = m_vertices.size();
|
||
|
|
for(int i=0;i<numVerts;i++)
|
||
|
|
{
|
||
|
|
btVector3 pt = trans * m_vertices[i];
|
||
|
|
btScalar dp = pt.dot(dir);
|
||
|
|
if(dp < minProj)
|
||
|
|
{
|
||
|
|
minProj = dp;
|
||
|
|
witnesPtMin = pt;
|
||
|
|
}
|
||
|
|
if(dp > maxProj)
|
||
|
|
{
|
||
|
|
maxProj = dp;
|
||
|
|
witnesPtMax = pt;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if(minProj>maxProj)
|
||
|
|
{
|
||
|
|
btSwap(minProj,maxProj);
|
||
|
|
btSwap(witnesPtMin,witnesPtMax);
|
||
|
|
}
|
||
|
|
}
|