#include "btMiniSDF.h"
//
//Based on code from DiscreGrid, https://github.com/InteractiveComputerGraphics/Discregrid
//example:
//GenerateSDF.exe -r "32 32 32" -d "-1.6 -1.6 -.6 1.6 1.6 .6" concave_box.obj
//The MIT License (MIT)
//
//Copyright (c) 2017 Dan Koschier
//
#include <limits.h>
#include <string.h> //memcpy
struct btSdfDataStream
{
const char* m_data;
int m_size;
int m_currentOffset;
btSdfDataStream(const char* data, int size)
:m_data(data),
m_size(size),
m_currentOffset(0)
{
}
template<class T> bool read(T& val)
{
int bytes = sizeof(T);
if (m_currentOffset+bytes<=m_size)
{
char* dest = (char*)&val;
memcpy(dest,&m_data[m_currentOffset],bytes);
m_currentOffset+=bytes;
return true;
}
btAssert(0);
return false;
}
};
bool btMiniSDF::load(const char* data, int size)
{
int fileSize = -1;
btSdfDataStream ds(data,size);
{
double buf[6];
ds.read(buf);
m_domain.m_min[0] = buf[0];
m_domain.m_min[1] = buf[1];
m_domain.m_min[2] = buf[2];
m_domain.m_min[3] = 0;
m_domain.m_max[0] = buf[3];
m_domain.m_max[1] = buf[4];
m_domain.m_max[2] = buf[5];
m_domain.m_max[3] = 0;
}
{
unsigned int buf2[3];
ds.read(buf2);
m_resolution[0] = buf2[0];
m_resolution[1] = buf2[1];
m_resolution[2] = buf2[2];
}
{
double buf[3];
ds.read(buf);
m_cell_size[0] = buf[0];
m_cell_size[1] = buf[1];
m_cell_size[2] = buf[2];
}
{
double buf[3];
ds.read(buf);
m_inv_cell_size[0] = buf[0];
m_inv_cell_size[1] = buf[1];
m_inv_cell_size[2] = buf[2];
}
{
unsigned long long int cells;
ds.read(cells);
m_n_cells = cells;
}
{
unsigned long long int fields;
ds.read(fields);
m_n_fields = fields;
}
unsigned long long int nodes0;
std::size_t n_nodes0;
ds.read(nodes0);
n_nodes0 = nodes0;
if (n_nodes0 > 1024 * 1024 * 1024)
{
return m_isValid;
}
m_nodes.resize(n_nodes0);
for (unsigned int i=0;i<n_nodes0;i++)
{
unsigned long long int n_nodes1;
ds.read(n_nodes1);
btAlignedObjectArray<double>& nodes = m_nodes[i];
nodes.resize(n_nodes1);
for ( int j=0;j<nodes.size();j++)
{
double& node = nodes[j];
ds.read(node);
}
}
unsigned long long int n_cells0;
ds.read(n_cells0);
m_cells.resize(n_cells0);
for (int i=0;i<n_cells0;i++)
{
unsigned long long int n_cells1;
btAlignedObjectArray<btCell32 >& cells = m_cells[i];
ds.read(n_cells1);
cells.resize(n_cells1);
for (int j=0;j<n_cells1;j++)
{
btCell32& cell = cells[j];
ds.read(cell);
}
}
{
unsigned long long int n_cell_maps0;
ds.read(n_cell_maps0);
m_cell_map.resize(n_cell_maps0);
for (int i=0;i<n_cell_maps0;i++)
{
unsigned long long int n_cell_maps1;
btAlignedObjectArray<unsigned int>& cell_maps = m_cell_map[i];
ds.read(n_cell_maps1);
cell_maps.resize(n_cell_maps1);
for (int j=0;j<n_cell_maps1;j++)
{
unsigned int& cell_map = cell_maps[j];
ds.read(cell_map);
}
}
}
m_isValid = (ds.m_currentOffset == ds.m_size);
return m_isValid;
}
unsigned int btMiniSDF::multiToSingleIndex(btMultiIndex const & ijk) const
{
return m_resolution[1] * m_resolution[0] * ijk.ijk[2] + m_resolution[0] * ijk.ijk[1] + ijk.ijk[0];
}
btAlignedBox3d
btMiniSDF::subdomain(btMultiIndex const& ijk) const
{
btAssert(m_isValid);
btVector3 tmp;
tmp.m_floats[0] = m_cell_size[0]*(double)ijk.ijk[0];
tmp.m_floats[1] = m_cell_size[1]*(double)ijk.ijk[1];
tmp.m_floats[2] = m_cell_size[2]*(double)ijk.ijk[2];
btVector3 origin = m_domain.min() + tmp;
btAlignedBox3d box = btAlignedBox3d (origin, origin + m_cell_size);
return box;
}
btMultiIndex
btMiniSDF::singleToMultiIndex(unsigned int l) const
{
btAssert(m_isValid);
unsigned int n01 = m_resolution[0] * m_resolution[1];
unsigned int k = l / n01;
unsigned int temp = l % n01;
unsigned int j = temp / m_resolution[0];
unsigned int i = temp % m_resolution[0];
btMultiIndex mi;
mi.ijk[0] = i;
mi.ijk[1] = j;
mi.ijk[2] = k;
return mi;
}
btAlignedBox3d
btMiniSDF::subdomain(unsigned int l) const
{
btAssert(m_isValid);
return subdomain(singleToMultiIndex(l));
}
btShapeMatrix
btMiniSDF::shape_function_(btVector3 const& xi, btShapeGradients* gradient) const
{
btAssert(m_isValid);
btShapeMatrix res;
btScalar x = xi[0];
btScalar y = xi[1];
btScalar z = xi[2];
btScalar x2 = x*x;
btScalar y2 = y*y;
btScalar z2 = z*z;
btScalar _1mx = 1.0 - x;
btScalar _1my = 1.0 - y;
btScalar _1mz = 1.0 - z;
btScalar _1px = 1.0 + x;
btScalar _1py = 1.0 + y;
btScalar _1pz = 1.0 + z;
btScalar _1m3x = 1.0 - 3.0 * x;
btScalar _1m3y = 1.0 - 3.0 * y;
btScalar _1m3z = 1.0 - 3.0 * z;
btScalar _1p3x = 1.0 + 3.0 * x;
btScalar _1p3y = 1.0 + 3.0 * y;
btScalar _1p3z = 1.0 + 3.0 * z;
btScalar _1mxt1my = _1mx * _1my;
btScalar _1mxt1py = _1mx * _1py;
btScalar _1pxt1my = _1px * _1my;
btScalar _1pxt1py = _1px * _1py;
btScalar _1mxt1mz = _1mx * _1mz;
btScalar _1mxt1pz = _1mx * _1pz;
btScalar _1pxt1mz = _1px * _1mz;
btScalar _1pxt1pz = _1px * _1pz;
btScalar _1myt1mz = _1my * _1mz;
btScalar _1myt1pz = _1my * _1pz;
btScalar _1pyt1mz = _1py * _1mz;
btScalar _1pyt1pz = _1py * _1pz;
btScalar _1mx2 = 1.0 - x2;
btScalar _1my2 = 1.0 - y2;
btScalar _1mz2 = 1.0 - z2;
// Corner nodes.
btScalar fac = 1.0 / 64.0 * (9.0 * (x2 + y2 + z2) - 19.0);
res[0] = fac * _1mxt1my * _1mz;
res[1] = fac * _1pxt1my * _1mz;
res[2] = fac * _1mxt1py * _1mz;
res[3] = fac * _1pxt1py * _1mz;
res[4] = fac * _1mxt1my * _1pz;
res[5] = fac * _1pxt1my * _1pz;
res[6] = fac * _1mxt1py * _1pz;
res[7] = fac * _1pxt1py * _1pz;
// Edge nodes.
fac = 9.0 / 64.0 * _1mx2;
btScalar fact1m3x = fac * _1m3x;
btScalar fact1p3x = fac * _1p3x;
res[ 8] = fact1m3x * _1myt1mz;
res[ 9] = fact1p3x * _1myt1mz;
res[10] = fact1m3x * _1myt1pz;
res[11] = fact1p3x * _1myt1pz;
res[12] = fact1m3x * _1pyt1mz;
res[13] = fact1p3x * _1pyt1mz;
res[14] = fact1m3x * _1pyt1pz;
res[15] = fact1p3x * _1pyt1pz;
fac = 9.0 / 64.0 * _1my2;
btScalar fact1m3y = fac * _1m3y;
btScalar fact1p3y = fac * _1p3y;
res[16] = fact1m3y * _1mxt1mz;
res[17] = fact1p3y * _1mxt1mz;
res[18] = fact1m3y * _1pxt1mz;
res[19] = fact1p3y * _1pxt1mz;
res[20] = fact1m3y * _1mxt1pz;
res[21] = fact1p3y * _1mxt1pz;
res[22] = fact1m3y * _1pxt1pz;
res[23] = fact1p3y * _1pxt1pz;
fac = 9.0 / 64.0 * _1mz2;
btScalar fact1m3z = fac * _1m3z;
btScalar fact1p3z = fac * _1p3z;
res[24] = fact1m3z * _1mxt1my;
res[25] = fact1p3z * _1mxt1my;
res[26] = fact1m3z * _1mxt1py;
res[27] = fact1p3z * _1mxt1py;
res[28] = fact1m3z * _1pxt1my;
res[29] = fact1p3z * _1pxt1my;
res[30] = fact1m3z * _1pxt1py;
res[31] = fact1p3z * _1pxt1py;
if (gradient)
{
btShapeGradients& dN = *gradient;
btScalar _9t3x2py2pz2m19 = 9.0 * (3.0 * x2 + y2 + z2) - 19.0;
btScalar _9tx2p3y2pz2m19 = 9.0 * (x2 + 3.0 * y2 + z2) - 19.0;
btScalar _9tx2py2p3z2m19 = 9.0 * (x2 + y2 + 3.0 * z2) - 19.0;
btScalar _18x = 18.0 * x;
btScalar _18y = 18.0 * y;
btScalar _18z = 18.0 * z;
btScalar _3m9x2 = 3.0 - 9.0 * x2;
btScalar _3m9y2 = 3.0 - 9.0 * y2;
btScalar _3m9z2 = 3.0 - 9.0 * z2;
btScalar _2x = 2.0 * x;
btScalar _2y = 2.0 * y;
btScalar _2z = 2.0 * z;
btScalar _18xm9t3x2py2pz2m19 = _18x - _9t3x2py2pz2m19;
btScalar _18xp9t3x2py2pz2m19 = _18x + _9t3x2py2pz2m19;
btScalar _18ym9tx2p3y2pz2m19 = _18y - _9tx2p3y2pz2m19;
btScalar _18yp9tx2p3y2pz2m19 = _18y + _9tx2p3y2pz2m19;
btScalar _18zm9tx2py2p3z2m19 = _18z - _9tx2py2p3z2m19;
btScalar _18zp9tx2py2p3z2m19 = _18z + _9tx2py2p3z2m19;
dN(0,0) =_18xm9t3x2py2pz2m19 * _1myt1mz;
dN(0,1) =_1mxt1mz * _18ym9tx2p3y2pz2m19;
dN(0,2) =_1mxt1my * _18zm9tx2py2p3z2m19;
dN(1,0) =_18xp9t3x2py2pz2m19 * _1myt1mz;
dN(1,1) =_1pxt1mz * _18ym9tx2p3y2pz2m19;
dN(1,2) =_1pxt1my * _18zm9tx2py2p3z2m19;
dN(2,0) =_18xm9t3x2py2pz2m19 * _1pyt1mz;
dN(2,1) =_1mxt1mz * _18yp9tx2p3y2pz2m19;
dN(2,2) =_1mxt1py * _18zm9tx2py2p3z2m19;
dN(3,0) =_18xp9t3x2py2pz2m19 * _1pyt1mz;
dN(3,1) =_1pxt1mz * _18yp9tx2p3y2pz2m19;
dN(3,2) =_1pxt1py * _18zm9tx2py2p3z2m19;
dN(4,0) =_18xm9t3x2py2pz2m19 * _1myt1pz;
dN(4,1) =_1mxt1pz * _18ym9tx2p3y2pz2m19;
dN(4,2) =_1mxt1my * _18zp9tx2py2p3z2m19;
dN(5,0) =_18xp9t3x2py2pz2m19 * _1myt1pz;
dN(5,1) =_1pxt1pz * _18ym9tx2p3y2pz2m19;
dN(5,2) =_1pxt1my * _18zp9tx2py2p3z2m19;
dN(6,0) =_18xm9t3x2py2pz2m19 * _1pyt1pz;
dN(6,1) =_1mxt1pz * _18yp9tx2p3y2pz2m19;
dN(6,2) =_1mxt1py * _18zp9tx2py2p3z2m19;
dN(7,0) =_18xp9t3x2py2pz2m19 * _1pyt1pz;
dN(7,1) =_1pxt1pz * _18yp9tx2p3y2pz2m19;
dN(7,2) =_1pxt1py * _18zp9tx2py2p3z2m19;
dN.topRowsDivide(8, 64.0);
btScalar _m3m9x2m2x = -_3m9x2 - _2x;
btScalar _p3m9x2m2x = _3m9x2 - _2x;
btScalar _1mx2t1m3x = _1mx2 * _1m3x;
btScalar _1mx2t1p3x = _1mx2 * _1p3x;
dN( 8,0) = _m3m9x2m2x * _1myt1mz,
dN( 8,1) = -_1mx2t1m3x * _1mz,
dN( 8,2) = -_1mx2t1m3x * _1my;
dN( 9,0) = _p3m9x2m2x * _1myt1mz,
dN( 9,1) = -_1mx2t1p3x * _1mz,
dN( 9,2) = -_1mx2t1p3x * _1my;
dN(10,0) = _m3m9x2m2x * _1myt1pz,
dN(10,1) = -_1mx2t1m3x * _1pz,
dN(10,2) = _1mx2t1m3x * _1my;
dN(11,0) = _p3m9x2m2x * _1myt1pz,
dN(11,1) = -_1mx2t1p3x * _1pz,
dN(11,2) = _1mx2t1p3x * _1my;
dN(12,0) = _m3m9x2m2x * _1pyt1mz,
dN(12,1) = _1mx2t1m3x * _1mz,
dN(12,2) = -_1mx2t1m3x * _1py;
dN(13,0) = _p3m9x2m2x * _1pyt1mz,
dN(13,1) = _1mx2t1p3x * _1mz,
dN(13,2) = -_1mx2t1p3x * _1py;
dN(14,0) = _m3m9x2m2x * _1pyt1pz,
dN(14,1) = _1mx2t1m3x * _1pz,
dN(14,2) = _1mx2t1m3x * _1py;
dN(15,0) = _p3m9x2m2x * _1pyt1pz,
dN(15,1) = _1mx2t1p3x * _1pz,
dN(15,2) = _1mx2t1p3x * _1py;
btScalar _m3m9y2m2y = -_3m9y2 - _2y;
btScalar _p3m9y2m2y = _3m9y2 - _2y;
btScalar _1my2t1m3y = _1my2 * _1m3y;
btScalar _1my2t1p3y = _1my2 * _1p3y;
dN(16,0) = -_1my2t1m3y * _1mz,
dN(16,1) = _m3m9y2m2y * _1mxt1mz,
dN(16,2) = -_1my2t1m3y * _1mx;
dN(17,0) = -_1my2t1p3y * _1mz,
dN(17,1) = _p3m9y2m2y * _1mxt1mz,
dN(17,2) = -_1my2t1p3y * _1mx;
dN(18,0) = _1my2t1m3y * _1mz,
dN(18,1) = _m3m9y2m2y * _1pxt1mz,
dN(18,2) = -_1my2t1m3y * _1px;
dN(19,0) = _1my2t1p3y * _1mz,
dN(19,1) = _p3m9y2m2y * _1pxt1mz,
dN(19,2) = -_1my2t1p3y * _1px;
dN(20,0) = -_1my2t1m3y * _1pz,
dN(20,1) = _m3m9y2m2y * _1mxt1pz,
dN(20,2) = _1my2t1m3y * _1mx;
dN(21,0) = -_1my2t1p3y * _1pz,
dN(21,1) = _p3m9y2m2y * _1mxt1pz,
dN(21,2) = _1my2t1p3y * _1mx;
dN(22,0) = _1my2t1m3y * _1pz,
dN(22,1) = _m3m9y2m2y * _1pxt1pz,
dN(22,2) = _1my2t1m3y * _1px;
dN(23,0) = _1my2t1p3y * _1pz,
dN(23,1) = _p3m9y2m2y * _1pxt1pz,
dN(23,2) = _1my2t1p3y * _1px;
btScalar _m3m9z2m2z = -_3m9z2 - _2z;
btScalar _p3m9z2m2z = _3m9z2 - _2z;
btScalar _1mz2t1m3z = _1mz2 * _1m3z;
btScalar _1mz2t1p3z = _1mz2 * _1p3z;
dN(24,0) = -_1mz2t1m3z * _1my,
dN(24,1) = -_1mz2t1m3z * _1mx,
dN(24,2) = _m3m9z2m2z * _1mxt1my;
dN(25,0) = -_1mz2t1p3z * _1my,
dN(25,1) = -_1mz2t1p3z * _1mx,
dN(25,2) = _p3m9z2m2z * _1mxt1my;
dN(26,0) = -_1mz2t1m3z * _1py,
dN(26,1) = _1mz2t1m3z * _1mx,
dN(26,2) = _m3m9z2m2z * _1mxt1py;
dN(27,0) = -_1mz2t1p3z * _1py,
dN(27,1) = _1mz2t1p3z * _1mx,
dN(27,2) = _p3m9z2m2z * _1mxt1py;
dN(28,0) = _1mz2t1m3z * _1my,
dN(28,1) = -_1mz2t1m3z * _1px,
dN(28,2) = _m3m9z2m2z * _1pxt1my;
dN(29,0) = _1mz2t1p3z * _1my,
dN(29,1) = -_1mz2t1p3z * _1px,
dN(29,2) = _p3m9z2m2z * _1pxt1my;
dN(30,0) = _1mz2t1m3z * _1py,
dN(30,1) = _1mz2t1m3z * _1px,
dN(30,2) = _m3m9z2m2z * _1pxt1py;
dN(31,0) = _1mz2t1p3z * _1py,
dN(31,1) = _1mz2t1p3z * _1px,
dN(31,2) = _p3m9z2m2z * _1pxt1py;
dN.bottomRowsMul(32u - 8u, 9.0 / 64.0);
}
return res;
}
bool btMiniSDF::interpolate(unsigned int field_id, double& dist, btVector3 const& x,
btVector3* gradient) const
{
btAssert(m_isValid);
if (!m_isValid)
return false;
if (!m_domain.contains(x))
return false;
btVector3 tmpmi = ((x - m_domain.min())*(m_inv_cell_size));//.cast<unsigned int>().eval();
unsigned int mi[3] = {(unsigned int )tmpmi[0],(unsigned int )tmpmi[1],(unsigned int )tmpmi[2]};
if (mi[0] >= m_resolution[0])
mi[0] = m_resolution[0]-1;
if (mi[1] >= m_resolution[1])
mi[1] = m_resolution[1]-1;
if (mi[2] >= m_resolution[2])
mi[2] = m_resolution[2]-1;
btMultiIndex mui;
mui.ijk[0] = mi[0];
mui.ijk[1] = mi[1];
mui.ijk[2] = mi[2];
int i = multiToSingleIndex(mui);
unsigned int i_ = m_cell_map[field_id][i];
if (i_ == UINT_MAX)
return false;
btAlignedBox3d sd = subdomain(i);
i = i_;
btVector3 d = sd.m_max-sd.m_min;//.diagonal().eval();
btVector3 denom = (sd.max() - sd.min());
btVector3 c0 = btVector3(2.0,2.0,2.0)/denom;
btVector3 c1 = (sd.max() + sd.min())/denom;
btVector3 xi = (c0*x - c1);
btCell32 const& cell = m_cells[field_id][i];
if (!gradient)
{
//auto phi = m_coefficients[field_id][i].dot(shape_function_(xi, 0));
double phi = 0.0;
btShapeMatrix N = shape_function_(xi, 0);
for (unsigned int j = 0u; j < 32u; ++j)
{
unsigned int v = cell.m_cells[j];
double c = m_nodes[field_id][v];
if (c == DBL_MAX)
{
return false;;
}
phi += c * N[j];
}
dist = phi;
return true;
}
btShapeGradients dN;
btShapeMatrix N = shape_function_(xi, &dN);
double phi = 0.0;
gradient->setZero();
for (unsigned int j = 0u; j < 32u; ++j)
{
unsigned int v = cell.m_cells[j];
double c = m_nodes[field_id][v];
if (c == DBL_MAX)
{
gradient->setZero();
return false;
}
phi += c * N[j];
(*gradient)[0] += c * dN(j, 0);
(*gradient)[1] += c * dN(j, 1);
(*gradient)[2] += c * dN(j, 2);
}
(*gradient) *= c0;
dist = phi;
return true;
}