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fixed btSoftBodyConcaveCollisionAlgorithm, wrong bounding box transformation

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added vertex welding option for btTriangleMesh (brute-force slow)
reject appendFace for some degenerate triangles (all 3 vertices/nodes need to be different)
add setVelocity method for btSoftBody
This commit is contained in:
erwin.coumans
2008-09-26 21:59:03 +00:00
parent e0d1c1d057
commit 682a0a1b90
5 changed files with 99 additions and 72 deletions
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98
src/BulletCollision/CollisionShapes/btTriangleMesh.cpp
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@@ -19,7 +19,8 @@ subject to the following restrictions:
btTriangleMesh::btTriangleMesh (bool use32bitIndices,bool use4componentVertices)
:m_use32bitIndices(use32bitIndices),
m_use4componentVertices(use4componentVertices)
m_use4componentVertices(use4componentVertices),
m_weldingThreshold(0.0)
{
btIndexedMesh meshIndex;
meshIndex.m_numTriangles = 0;
@@ -60,49 +61,66 @@ m_use4componentVertices(use4componentVertices)
}
void btTriangleMesh::addIndex(int index)
{
if (m_use32bitIndices)
{
m_32bitIndices.push_back(index);
m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_32bitIndices[0];
} else
{
m_16bitIndices.push_back(index);
m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_16bitIndices[0];
}
}
int btTriangleMesh::findOrAddVertex(const btVector3& vertex)
{
//return index of new/existing vertex
//todo: could use acceleration structure for this
if (m_use4componentVertices)
{
for (int i=0;i< m_4componentVertices.size();i++)
{
if ((m_4componentVertices[i]-vertex).length2() <= m_weldingThreshold)
{
return i;
}
}
m_indexedMeshes[0].m_numVertices++;
m_4componentVertices.push_back(vertex);
m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_4componentVertices[0];
return m_4componentVertices.size()-1;
} else
{
for (int i=0;i< m_3componentVertices.size();i+=3)
{
btVector3 vtx(m_3componentVertices[i],m_3componentVertices[i+1],m_3componentVertices[i+2]);
if ((vtx-vertex).length2() <= m_weldingThreshold)
{
return i/3;
}
}
m_3componentVertices.push_back(vertex.getX());
m_3componentVertices.push_back(vertex.getY());
m_3componentVertices.push_back(vertex.getZ());
m_indexedMeshes[0].m_numVertices++;
m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_3componentVertices[0];
return (m_3componentVertices.size()/3)-1;
}
}
void btTriangleMesh::addTriangle(const btVector3& vertex0,const btVector3& vertex1,const btVector3& vertex2)
{
m_indexedMeshes[0].m_numTriangles++;
m_indexedMeshes[0].m_numVertices+=3;
if (m_use4componentVertices)
{
m_4componentVertices.push_back(vertex0);
m_4componentVertices.push_back(vertex1);
m_4componentVertices.push_back(vertex2);
m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_4componentVertices[0];
} else
{
m_3componentVertices.push_back(vertex0.getX());
m_3componentVertices.push_back(vertex0.getY());
m_3componentVertices.push_back(vertex0.getZ());
m_3componentVertices.push_back(vertex1.getX());
m_3componentVertices.push_back(vertex1.getY());
m_3componentVertices.push_back(vertex1.getZ());
m_3componentVertices.push_back(vertex2.getX());
m_3componentVertices.push_back(vertex2.getY());
m_3componentVertices.push_back(vertex2.getZ());
m_indexedMeshes[0].m_vertexBase = (unsigned char*)&m_3componentVertices[0];
}
if (m_use32bitIndices)
{
int curIndex = m_32bitIndices.size();
m_32bitIndices.push_back(curIndex++);
m_32bitIndices.push_back(curIndex++);
m_32bitIndices.push_back(curIndex++);
m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_32bitIndices[0];
} else
{
short curIndex = static_cast<short>(m_16bitIndices.size());
m_16bitIndices.push_back(curIndex++);
m_16bitIndices.push_back(curIndex++);
m_16bitIndices.push_back(curIndex++);
m_indexedMeshes[0].m_triangleIndexBase = (unsigned char*) &m_16bitIndices[0];
}
addIndex(findOrAddVertex(vertex0));
addIndex(findOrAddVertex(vertex1));
addIndex(findOrAddVertex(vertex2));
}
int btTriangleMesh::getNumTriangles() const

8
src/BulletCollision/CollisionShapes/btTriangleMesh.h
View File

@@ -25,6 +25,7 @@ subject to the following restrictions:
///It allows either 32bit or 16bit indices, and 4 (x-y-z-w) or 3 (x-y-z) component vertices.
///If you want to share triangle/index data between graphics mesh and collision mesh (btBvhTriangleMeshShape), you can directly use btTriangleIndexVertexArray or derive your own class from btStridingMeshInterface.
///Performance of btTriangleMesh and btTriangleIndexVertexArray used in a btBvhTriangleMeshShape is the same.
///It has a brute-force option to weld together closeby vertices.
class btTriangleMesh : public btTriangleIndexVertexArray
{
btAlignedObjectArray<btVector3> m_4componentVertices;
@@ -34,11 +35,16 @@ class btTriangleMesh : public btTriangleIndexVertexArray
btAlignedObjectArray<unsigned short int> m_16bitIndices;
bool m_use32bitIndices;
bool m_use4componentVertices;
public:
btScalar m_weldingThreshold;
btTriangleMesh (bool use32bitIndices=true,bool use4componentVertices=true);
int findOrAddVertex(const btVector3& vertex);
void addIndex(int index);
bool getUse32bitIndices() const
{
return m_use32bitIndices;

21
src/BulletSoftBody/btSoftBody.cpp
View File

@@ -284,6 +284,13 @@ m_faces.push_back(f);
//
void btSoftBody::appendFace(int node0,int node1,int node2,Material* mat)
{
if (node0==node1)
return;
if (node1==node2)
return;
if (node2==node0)
return;
appendFace(-1,mat);
Face& f=m_faces[m_faces.size()-1];
btAssert(node0!=node1);
@@ -384,6 +391,20 @@ void btSoftBody::addVelocity(const btVector3& velocity)
for(int i=0,ni=m_nodes.size();i<ni;++i) addVelocity(velocity,i);
}
/* Set velocity for the entire body */
void btSoftBody::setVelocity( const btVector3& velocity)
{
for(int i=0,ni=m_nodes.size();i<ni;++i)
{
Node& n=m_nodes[i];
if(n.m_im>0)
{
n.m_v = velocity;
}
}
}
//
void btSoftBody::addVelocity(const btVector3& velocity,int node)
{

4
src/BulletSoftBody/btSoftBody.h
View File

@@ -677,6 +677,10 @@ public:
int node);
/* Add velocity to the entire body */
void addVelocity( const btVector3& velocity);
/* Set velocity for the entire body */
void setVelocity( const btVector3& velocity);
/* Add velocity to a node of the body */
void addVelocity( const btVector3& velocity,
int node);

40
src/BulletSoftBody/btSoftBodyConcaveCollisionAlgorithm.cpp
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@@ -32,7 +32,7 @@ subject to the following restrictions:
#include "BulletCollision/NarrowPhaseCollision/btSubSimplexConvexCast.h"
#include "BulletSoftBody/btSoftBody.h"
#define BT_SOFTBODY_TRIANGLE_EXTRUSION btScalar(0.3)
#define BT_SOFTBODY_TRIANGLE_EXTRUSION btScalar(0.06)//make this configurable
btSoftBodyConcaveCollisionAlgorithm::btSoftBodyConcaveCollisionAlgorithm( const btCollisionAlgorithmConstructionInfo& ci, btCollisionObject* body0,btCollisionObject* body1,bool isSwapped)
: btCollisionAlgorithm(ci),
@@ -210,44 +210,22 @@ btCollisionObject* ob = static_cast<btCollisionObject*>(m_triBody);
void btSoftBodyTriangleCallback::setTimeStepAndCounters(btScalar collisionMarginTriangle,const btDispatcherInfo& dispatchInfo,btManifoldResult* resultOut)
{
m_dispatchInfoPtr = &dispatchInfo;
m_collisionMarginTriangle = collisionMarginTriangle;
m_collisionMarginTriangle = collisionMarginTriangle+btScalar(BT_SOFTBODY_TRIANGLE_EXTRUSION);
m_resultOut = resultOut;
//recalc aabbs
// btTransform softbodyInTriangleSpace;
// softbodyInTriangleSpace = m_triBody->getWorldTransform().inverse() * m_softBody->getWorldTransform();
// btCollisionShape* convexShape = static_cast<btCollisionShape*>(m_convexBody->getCollisionShape());
//CollisionShape* triangleShape = static_cast<btCollisionShape*>(triBody->m_collisionShape);
btVector3 aabbWorldSpaceMin,aabbWorldSpaceMax;
m_softBody->getAabb(aabbWorldSpaceMin,aabbWorldSpaceMax);
btVector3 halfExtents = (aabbWorldSpaceMax-aabbWorldSpaceMin)*btScalar(0.5);
btVector3 softBodyCenter = (aabbWorldSpaceMax+aabbWorldSpaceMin)*btScalar(0.5);
btTransform triInverse = m_triBody->getWorldTransform().inverse();
btMatrix3x3 abs_b = triInverse.getBasis().absolute();
btPoint3 center = softBodyCenter + triInverse.getOrigin();
btVector3 extent = btVector3(abs_b[0].dot(halfExtents),
abs_b[1].dot(halfExtents),
abs_b[2].dot(halfExtents));
// extent += btVector3(getMargin(),getMargin(),getMargin());
m_aabbMin = center - extent;
m_aabbMax = center + extent;
btScalar extraMargin = collisionMarginTriangle+btScalar(BT_SOFTBODY_TRIANGLE_EXTRUSION);
btVector3 extra(extraMargin,extraMargin,extraMargin);
m_aabbMax += extra;
m_aabbMin -= extra;
/* btVector3 extra(2,2,2);
m_aabbMin = aabbWorldSpaceMin-extra;
m_aabbMax = aabbWorldSpaceMax+extra;
*/
btTransform softTransform;
softTransform.setIdentity();
softTransform.setOrigin(softBodyCenter);
btTransform convexInTriangleSpace;
convexInTriangleSpace = m_triBody->getWorldTransform().inverse() * softTransform;
btTransformAabb(halfExtents,m_collisionMarginTriangle,convexInTriangleSpace,m_aabbMin,m_aabbMax);
}
void btSoftBodyConcaveCollisionAlgorithm::clearCache()