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Added example of tetrahedral (volumetric) softbodies

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Keep camera distance positive when using mouse zoom
Updated autogenerated msvc projectfiles
Added glut 64 bit support
This commit is contained in:
erwin.coumans
2009-08-27 18:39:17 +00:00
parent f82cfc8259
commit f492899499
27 changed files with 429 additions and 3937 deletions
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71
src/BulletSoftBody/btSoftBody.cpp
View File

@@ -305,6 +305,34 @@ void btSoftBody::appendFace(int node0,int node1,int node2,Material* mat)
m_bUpdateRtCst=true;
}
//
void btSoftBody::appendTetra(int model,Material* mat)
{
Tetra t;
if(model>=0)
t=m_tetras[model];
else
{ ZeroInitialize(t);t.m_material=mat?mat:m_materials[0]; }
m_tetras.push_back(t);
}
//
void btSoftBody::appendTetra(int node0,
int node1,
int node2,
int node3,
Material* mat)
{
appendTetra(-1,mat);
Tetra& t=m_tetras[m_tetras.size()-1];
t.m_n[0] = &m_nodes[node0];
t.m_n[1] = &m_nodes[node1];
t.m_n[2] = &m_nodes[node2];
t.m_n[3] = &m_nodes[node3];
t.m_rv = VolumeOf(t.m_n[0]->m_x,t.m_n[1]->m_x,t.m_n[2]->m_x,t.m_n[3]->m_x);
m_bUpdateRtCst=true;
}
//
void btSoftBody::appendAnchor(int node,btRigidBody* body, bool disableCollisionBetweenLinkedBodies)
{
@@ -490,6 +518,49 @@ void btSoftBody::setTotalDensity(btScalar density)
setTotalMass(getVolume()*density,true);
}
//
void btSoftBody::setVolumeMass(btScalar mass)
{
btAlignedObjectArray<btScalar> ranks;
ranks.resize(m_nodes.size(),0);
for(int i=0;i<m_nodes.size();++i)
{
m_nodes[i].m_im=0;
}
for(int i=0;i<m_tetras.size();++i)
{
const Tetra& t=m_tetras[i];
for(int j=0;j<4;++j)
{
t.m_n[j]->m_im+=btFabs(t.m_rv);
ranks[int(t.m_n[j]-&m_nodes[0])]+=1;
}
}
for(int i=0;i<m_nodes.size();++i)
{
if(m_nodes[i].m_im>0)
{
m_nodes[i].m_im=ranks[i]/m_nodes[i].m_im;
}
}
setTotalMass(mass,false);
}
//
void btSoftBody::setVolumeDensity(btScalar density)
{
btScalar volume=0;
for(int i=0;i<m_tetras.size();++i)
{
const Tetra& t=m_tetras[i];
for(int j=0;j<4;++j)
{
volume+=btFabs(t.m_rv);
}
}
setVolumeMass(volume*density/6);
}
//
void btSoftBody::transform(const btTransform& trs)
{

25
src/BulletSoftBody/btSoftBody.h
View File

@@ -220,6 +220,16 @@ public:
btScalar m_ra; // Rest area
btDbvtNode* m_leaf; // Leaf data
};
/* Tetra */
struct Tetra : Feature
{
Node* m_n[4]; // Node pointers
btScalar m_rv; // Rest volume
btDbvtNode* m_leaf; // Leaf data
btVector3 m_c0[4]; // gradients
btScalar m_c1; // (4*kVST)/(im0+im1+im2+im3)
btScalar m_c2; // m_c1/sum(|g0..3|^2)
};
/* RContact */
struct RContact
{
@@ -574,6 +584,7 @@ public:
typedef btAlignedObjectArray<btDbvtNode*> tLeafArray;
typedef btAlignedObjectArray<Link> tLinkArray;
typedef btAlignedObjectArray<Face> tFaceArray;
typedef btAlignedObjectArray<Tetra> tTetraArray;
typedef btAlignedObjectArray<Anchor> tAnchorArray;
typedef btAlignedObjectArray<RContact> tRContactArray;
typedef btAlignedObjectArray<SContact> tSContactArray;
@@ -594,6 +605,7 @@ public:
tNodeArray m_nodes; // Nodes
tLinkArray m_links; // Links
tFaceArray m_faces; // Faces
tTetraArray m_tetras; // Tetras
tAnchorArray m_anchors; // Anchors
tRContactArray m_rcontacts; // Rigid contacts
tSContactArray m_scontacts; // Soft contacts
@@ -681,6 +693,15 @@ public:
int node1,
int node2,
Material* mat=0);
void appendTetra(int model,Material* mat);
//
void appendTetra(int node0,
int node1,
int node2,
int node3,
Material* mat=0);
/* Append anchor */
void appendAnchor( int node,
btRigidBody* body, bool disableCollisionBetweenLinkedBodies=false);
@@ -718,6 +739,10 @@ public:
bool fromfaces=false);
/* Set total density */
void setTotalDensity(btScalar density);
/* Set volume mass (using tetrahedrons) */
void setVolumeMass( btScalar mass);
/* Set volume density (using tetrahedrons) */
void setVolumeDensity( btScalar density);
/* Transform */
void transform( const btTransform& trs);
/* Translate */

147
src/BulletSoftBody/btSoftBodyHelpers.cpp
View File

@@ -310,6 +310,26 @@ void btSoftBodyHelpers::Draw( btSoftBody* psb,
idraw->drawLine(c.m_com,c.m_framexform*btVector3(0,0,10),btVector3(0,0,1));
}
}
/* Tetras */
if(0!=(drawflags&fDrawFlags::Tetras))
{
const btScalar scl=(btScalar)0.8;
const btScalar alp=(btScalar)1;
const btVector3 col((btScalar)0.7,(btScalar)0.7,(btScalar)0.7);
for(int i=0;i<psb->m_tetras.size();++i)
{
const btSoftBody::Tetra& t=psb->m_tetras[i];
if(0==(t.m_material->m_flags&btSoftBody::fMaterial::DebugDraw)) continue;
const btVector3 x[]={t.m_n[0]->m_x,t.m_n[1]->m_x,t.m_n[2]->m_x,t.m_n[3]->m_x};
const btVector3 c=(x[0]+x[1]+x[2]+x[3])/4;
idraw->drawTriangle((x[0]-c)*scl+c,(x[1]-c)*scl+c,(x[2]-c)*scl+c,col,alp);
idraw->drawTriangle((x[0]-c)*scl+c,(x[1]-c)*scl+c,(x[3]-c)*scl+c,col,alp);
idraw->drawTriangle((x[1]-c)*scl+c,(x[2]-c)*scl+c,(x[3]-c)*scl+c,col,alp);
idraw->drawTriangle((x[2]-c)*scl+c,(x[0]-c)*scl+c,(x[3]-c)*scl+c,col,alp);
}
}
/* Notes */
if(0!=(drawflags&fDrawFlags::Notes))
{
@@ -857,3 +877,130 @@ btSoftBody* btSoftBodyHelpers::CreateFromConvexHull(btSoftBodyWorldInfo& worldI
psb->randomizeConstraints();
return(psb);
}
static int nextLine(const char* buffer)
{
int numBytesRead=0;
while (*buffer != '\n')
{
buffer++;
numBytesRead++;
}
if (buffer[0]==0x0a)
{
buffer++;
numBytesRead++;
}
return numBytesRead;
}
/* Create from TetGen .ele, .face, .node data */
btSoftBody* btSoftBodyHelpers::CreateFromTetGenData(btSoftBodyWorldInfo& worldInfo,
const char* ele,
const char* face,
const char* node,
bool bfacelinks,
bool btetralinks,
bool bfacesfromtetras)
{
btAlignedObjectArray<btVector3> pos;
int nnode=0;
int ndims=0;
int nattrb=0;
int hasbounds=0;
int result = sscanf(node,"%d %d %d %d",&nnode,&ndims,&nattrb,&hasbounds);
result = sscanf(node,"%d %d %d %d",&nnode,&ndims,&nattrb,&hasbounds);
node += nextLine(node);
pos.resize(nnode);
for(int i=0;i<pos.size();++i)
{
int index=0;
//int bound=0;
float x,y,z,a;
sscanf(node,"%d %f %f %f",&index,&x,&y,&z);
// sn>>index;
// sn>>x;sn>>y;sn>>z;
node += nextLine(node);
//for(int j=0;j<nattrb;++j)
// sn>>a;
//if(hasbounds)
// sn>>bound;
pos[index].setX(btScalar(x));
pos[index].setY(btScalar(y));
pos[index].setZ(btScalar(z));
}
btSoftBody* psb=new btSoftBody(&worldInfo,nnode,&pos[0],0);
#if 0
if(face&&face[0])
{
int nface=0;
sf>>nface;sf>>hasbounds;
for(int i=0;i<nface;++i)
{
int index=0;
int bound=0;
int ni[3];
sf>>index;
sf>>ni[0];sf>>ni[1];sf>>ni[2];
sf>>bound;
psb->appendFace(ni[0],ni[1],ni[2]);
if(btetralinks)
{
psb->appendLink(ni[0],ni[1],0,true);
psb->appendLink(ni[1],ni[2],0,true);
psb->appendLink(ni[2],ni[0],0,true);
}
}
}
#endif
if(ele&&ele[0])
{
int ntetra=0;
int ncorner=0;
int neattrb=0;
sscanf(ele,"%d %d %d",&ntetra,&ncorner,&neattrb);
ele += nextLine(ele);
//se>>ntetra;se>>ncorner;se>>neattrb;
for(int i=0;i<ntetra;++i)
{
int index=0;
int ni[4],a;
//se>>index;
//se>>ni[0];se>>ni[1];se>>ni[2];se>>ni[3];
sscanf(ele,"%d %d %d %d %d",&index,&ni[0],&ni[1],&ni[2],&ni[3]);
ele+=nextLine(ele);
//for(int j=0;j<neattrb;++j)
// se>>a;
psb->appendTetra(ni[0],ni[1],ni[2],ni[3]);
if(btetralinks)
{
psb->appendLink(ni[0],ni[1],0,true);
psb->appendLink(ni[1],ni[2],0,true);
psb->appendLink(ni[2],ni[0],0,true);
psb->appendLink(ni[0],ni[3],0,true);
psb->appendLink(ni[1],ni[3],0,true);
psb->appendLink(ni[2],ni[3],0,true);
}
}
}
printf("Nodes: %u\r\n",psb->m_nodes.size());
printf("Links: %u\r\n",psb->m_links.size());
printf("Faces: %u\r\n",psb->m_faces.size());
printf("Tetras: %u\r\n",psb->m_tetras.size());
return(psb);
}

22
src/BulletSoftBody/btSoftBodyHelpers.h
View File

@@ -114,6 +114,28 @@ struct btSoftBodyHelpers
static btSoftBody* CreateFromConvexHull( btSoftBodyWorldInfo& worldInfo,
const btVector3* vertices,
int nvertices);
/* Export TetGen compatible .smesh file */
static void ExportAsSMeshFile( btSoftBody* psb,
const char* filename);
/* Create from TetGen .ele, .face, .node files */
static btSoftBody* CreateFromTetGenFile( btSoftBodyWorldInfo& worldInfo,
const char* ele,
const char* face,
const char* node,
bool bfacelinks,
bool btetralinks,
bool bfacesfromtetras);
/* Create from TetGen .ele, .face, .node data */
static btSoftBody* CreateFromTetGenData( btSoftBodyWorldInfo& worldInfo,
const char* ele,
const char* face,
const char* node,
bool bfacelinks,
bool btetralinks,
bool bfacesfromtetras);
};
#endif //SOFT_BODY_HELPERS_H